Score: 11.00 | Title: A conserved threonine residue in the juxtamembrane domain of the XA21 pattern recognition receptor is critical for kinase autophosphorylation and XA21-mediated immunity .
| Author: Chen X Chern M Canlas PE Jiang C Ruan D Cao P Ronald PC | Journal: J Biol Chem Type: MEDLINE | Literature: oryza Field: abstract Doc ID: pub20118235 | Abstract: Despite the key role that pattern recognition receptors ( PRRs ) play in regulating immunity in plants and animals , the mechanism of activation of the associated non-arginine-aspartate ( non-RD ) kinases is unknown .
The rice PRR XA21 recognizes the pathogen-associated molecular pattern , Ax21 ( activator of XA21-mediated immunity ) .
Here we show that the XA21 juxtamembrane ( JM ) domain is required for kinase autophosphorylation .
Threonine 705 in the XA21 JM domain is essential for XA21 autophosphorylation in vitro and XA21-mediated innate immunity in vivo .
The replacement of Thr ( 705 ) by an alanine or glutamic acid abolishes XA21 autophosphorylation and eliminates interactions between XA21 and four XA21-binding proteins in yeast and rice .
Although threonine residues analogous to Thr ( 705 ) of XA21 are present in the JM domains of most RD and non-RD plant receptor-like kinases , this residue is not required for autophosphorylation of the Arabidopsis RD RLK BRI1 ( brassinosteroid insensitive 1 ) .
The threonine 705 of XA21 is conserved only in the JM domains of plant RLKs but not in those of fly , human , or mouse suggesting distinct regulatory mechanisms .
These results contribute to growing knowledge regarding the mechanism by which non-RD RLKs function in plant .
| Matching Sentences: [ Sen. 4, subscore: 3.00 ]: Threonine 705 in the XA21 JM domain is essential for XA21 autophosphorylation in vitro and XA21-mediated innate immunity in vivo . [ Sen. 5, subscore: 3.00 ]: The replacement of Thr ( 705 ) by an alanine or glutamic acid abolishes XA21 autophosphorylation and eliminates interactions between XA21 and four XA21-binding proteins in yeast and rice . [ Sen. 2, subscore: 2.00 ]: The rice PRR XA21 recognizes the pathogen-associated molecular pattern , Ax21 ( activator of XA21-mediated immunity ) . [ Sen. 3, subscore: 1.00 ]: Here we show that the XA21 juxtamembrane ( JM ) domain is required for kinase autophosphorylation . [ Sen. 6, subscore: 1.00 ]: Although threonine residues analogous to Thr ( 705 ) of XA21 are present in the JM domains of most RD and non-RD plant receptor-like kinases , this residue is not required for autophosphorylation of the Arabidopsis RD RLK BRI1 ( brassinosteroid insensitive 1 ) . [ Sen. 7, subscore: 1.00 ]: The threonine 705 of XA21 is conserved only in the JM domains of plant RLKs but not in those of fly , human , or mouse suggesting distinct regulatory mechanisms .
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Score: 10.00 | Title: Plasma membrane localization and potential endocytosis of constitutively expressed XA21 proteins in transgenic rice .
| Author: Chen F Gao MJ Miao YS Yuan YX Wang MY Li Q Mao BZ Jiang LW He ZH | Journal: Mol Plant Type: MEDLINE | Literature: oryza Field: abstract Doc ID: pub20616165 | Abstract: The rice pattern recognition receptor ( PRR ) XA21 confers race-specific resistance in leaf infection by bacterial blight Xathomonas oryzae pv . oryzae ( Xoo ) , and was shown to be primarily localized to the endoplasmic reticulum ( ER ) when expressed with its native promoter or overexpressed in the protoplast However , whether the protein is still ER-localization in the intact cell when overexpressed remains to be identified .
Here , we showed that XA21 , its kinase-dead mutant XA21P ( K736EP ) , and the triple autophosphorylation mutant XA21P ( S686A/T688A/S699A ) GFP fusions were primarily localized to the plasma membrane ( PM ) when overexpressed in the intact transgenic rice cell , and also localized to the ER in the transgenic protoplast The transgenic plants constitutively expressing the wild-type XA21 or its GFP fusion displayed race-specific resistance to Xoo at the adult and seedling stages .
XA21 and XA21P ( K736EP ) could be internalized probably via the SCAMP-positive early endosomal compartment in the protoplast , suggesting that XA21 might be endocytosed to initiate resistance responses during pathogen infection .
We also established a root infection system and demonstrated that XA21 also mediated race-specific resistance responses to Xoo in the root .
Our current study provides an insight into the nature of the XA21-mediated resistance and a practical approach using the root cell system to further dissect the cellular signaling of the PRR during the rice-Xoo interaction .
| Matching Sentences: [ Sen. 2, subscore: 4.00 ]: Here , we showed that XA21 , its kinase-dead mutant XA21P ( K736EP ) , and the triple autophosphorylation mutant XA21P ( S686A/T688A/S699A ) GFP fusions were primarily localized to the plasma membrane ( PM ) when overexpressed in the intact transgenic rice cell , and also localized to the ER in the transgenic protoplast The transgenic plants constitutively expressing the wild-type XA21 or its GFP fusion displayed race-specific resistance to Xoo at the adult and seedling stages . [ Sen. 3, subscore: 3.00 ]: XA21 and XA21P ( K736EP ) could be internalized probably via the SCAMP-positive early endosomal compartment in the protoplast , suggesting that XA21 might be endocytosed to initiate resistance responses during pathogen infection . [ Sen. 1, subscore: 1.00 ]: The rice pattern recognition receptor ( PRR ) XA21 confers race-specific resistance in leaf infection by bacterial blight Xathomonas oryzae pv . oryzae ( Xoo ) , and was shown to be primarily localized to the endoplasmic reticulum ( ER ) when expressed with its native promoter or overexpressed in the protoplast However , whether the protein is still ER-localization in the intact cell when overexpressed remains to be identified . [ Sen. 4, subscore: 1.00 ]: We also established a root infection system and demonstrated that XA21 also mediated race-specific resistance responses to Xoo in the root . [ Sen. 5, subscore: 1.00 ]: Our current study provides an insight into the nature of the XA21-mediated resistance and a practical approach using the root cell system to further dissect the cellular signaling of the PRR during the rice-Xoo interaction .
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Score: 10.00 | Title: Adaptive evolution of Xa21 homologs in Gramineae .
| Author: Tan S Wang D Ding J Tian D Zhang X Yang S | Journal: Genetica Type: In-Process | Literature: oryza Field: abstract Doc ID: pub22451352 | Abstract: The XA21 protein has broad spectrum resistance against Xanthomonas oryzae pv . oryzae .
Although Xa21-mediated immunity is well characterized , little is known about the origin and evolutionary history of this gene in grasses .
Therefore , we analyzed all Xa21 gene homologs in eight whole-genome sequenced rice lines , as well as in four gramineous genomes , rice , Brachypodium , sorghum and maize ; using Arabidopsis Xa21 homologs as outgroups , 17 , 7 , 7 and 3 Xa21 homologs were detected in these four grasses , respectively .
Synteny and phylogenetic analysis showed that frequent gene translocation , duplication and/or loss , have occurred at Xa21 homologous loci , suggesting that they have undergone or are undergoing rapid generation of copy number variations .
Within the rice species , the high level of nucleotide diversity between Xa21-like orthologs showed a strong association with the presence/absence haplotypes , suggesting that the genetic structure of rice lines plays an important role in the variations between these Xa21-like orthologs .
Strongly positive selection was detected in the core region of the leucine-rich repeat domains of the Xa21 subclade among the rice lines , indicating that the rapid gene diversification of Xa21 homologs may be a strategy for a given species to adapt to the changing spectrum of species-specific pathogens .
| Matching Sentences: [ Sen. 3, subscore: 3.00 ]: Therefore , we analyzed all Xa21 gene homologs in eight whole-genome sequenced rice lines , as well as in four gramineous genomes , rice , Brachypodium , sorghum and maize ; using Arabidopsis Xa21 homologs as outgroups , 17 , 7 , 7 and 3 Xa21 homologs were detected in these four grasses , respectively . [ Sen. 5, subscore: 2.00 ]: Within the rice species , the high level of nucleotide diversity between Xa21-like orthologs showed a strong association with the presence/absence haplotypes , suggesting that the genetic structure of rice lines plays an important role in the variations between these Xa21-like orthologs . [ Sen. 6, subscore: 2.00 ]: Strongly positive selection was detected in the core region of the leucine-rich repeat domains of the Xa21 subclade among the rice lines , indicating that the rapid gene diversification of Xa21 homologs may be a strategy for a given species to adapt to the changing spectrum of species-specific pathogens . [ Sen. 1, subscore: 1.00 ]: The XA21 protein has broad spectrum resistance against Xanthomonas oryzae pv . oryzae . [ Sen. 2, subscore: 1.00 ]: Although Xa21-mediated immunity is well characterized , little is known about the origin and evolutionary history of this gene in grasses . [ Sen. 4, subscore: 1.00 ]: Synteny and phylogenetic analysis showed that frequent gene translocation , duplication and/or loss , have occurred at Xa21 homologous loci , suggesting that they have undergone or are undergoing rapid generation of copy number variations .
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Score: 9.00 | Title: Biochemical characterization of the kinase domain of the rice disease resistance receptor-like kinase XA21 .
| Author: Liu GZ Pi LY Walker JC Ronald PC Song WY .
| Journal: J Biol . Chem . Type: ARTICLE | Literature: oryza Field: abstract Doc ID: pub11927577 | Abstract: The rice disease resistance gene , Xa21 , encodes a receptor kinase-like protein consisting of leucine-rich repeats in the putative extracellular domain and a serine/threonine kinase in the putative intracellular domain .
The putative XA21 kinase domain was expressed as maltose-binding and glutathione S-transferase fusion proteins in Escherichia coli .
The fusion proteins are capable of autophosphorylation .
Phosphoamino acid analysis of the glutathione S-transferase fusion protein indicates that only serine and threonine residues are phosphorylated .
The relative phosphorylation rate of the XA21 kinase against increasing enzyme concentrations follows a first-order rather than second-order kinetics , indicating an intramolecular phosphorylation mechanism .
Moreover , the active XA21 kinase can not phosphorylate a kinase-deficient mutant of XA21 kinase .
The enzymatic activity of the XA21 kinase in a buffer containing Mn ( 2+ ) is at least 15 times higher than that with Mg ( 2+ ) .
The K ( m ) and V ( max ) of XA21 kinase for ATP are 0 . 3 microm and 8 . 4 nmol/mg/min , respectively .
Tryptic phosphopeptide mapping reveals that multiple sites on the XA21 kinase are phosphorylated .
Finally , our data suggest that the region of XA21 kinase corresponding to the RD kinase activation domain is not phosphorylated , revealing a distinct mode of action compared with the tomato Pto serine/threonine kinase conferring disease resistance . | Matching Sentences: [ Sen. 6, subscore: 2.00 ]: Moreover , the active XA21 kinase can not phosphorylate a kinase-deficient mutant of XA21 kinase . [ Sen. 1, subscore: 1.00 ]: The rice disease resistance gene , Xa21 , encodes a receptor kinase-like protein consisting of leucine-rich repeats in the putative extracellular domain and a serine/threonine kinase in the putative intracellular domain . [ Sen. 2, subscore: 1.00 ]: The putative XA21 kinase domain was expressed as maltose-binding and glutathione S-transferase fusion proteins in Escherichia coli . [ Sen. 5, subscore: 1.00 ]: The relative phosphorylation rate of the XA21 kinase against increasing enzyme concentrations follows a first-order rather than second-order kinetics , indicating an intramolecular phosphorylation mechanism . [ Sen. 7, subscore: 1.00 ]: The enzymatic activity of the XA21 kinase in a buffer containing Mn ( 2+ ) is at least 15 times higher than that with Mg ( 2+ ) . [ Sen. 8, subscore: 1.00 ]: The K ( m ) and V ( max ) of XA21 kinase for ATP are 0 . 3 microm and 8 . 4 nmol/mg/min , respectively . [ Sen. 9, subscore: 1.00 ]: Tryptic phosphopeptide mapping reveals that multiple sites on the XA21 kinase are phosphorylated . [ Sen. 10, subscore: 1.00 ]: Finally , our data suggest that the region of XA21 kinase corresponding to the RD kinase activation domain is not phosphorylated , revealing a distinct mode of action compared with the tomato Pto serine/threonine kinase conferring disease resistance .
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Score: 9.00 | Title: Rice XA21 Binding Protein 3 Is a Ubiquitin Ligase Required for Full Xa21-Mediated Disease Resistance .
| Author: Wang YS Pi LY Chen X Chakrabarty PK Jiang J De Leon AL Liu GZ Li L Benny U Oard J Ronald PC Song WY .
| Journal: Type: ARTICLE | Literature: oryza Field: abstract Doc ID: pub17172358 | Abstract: XA21 is a receptor-like kinase protein in rice ( Oryza sativa ) that confers gene-for-gene resistance to specific races of the causal agent of bacterial blight disease , Xanthomonas oryzae pv oryzae .
We identified XA21 binding protein 3 ( XB3 ) , an E3 ubiquitin ligase , as a substrate for the XA21 Ser and Thr kinase .
The interaction between XB3 and the kinase domain of XA21 has been shown in yeast and in vitro , and the physical association between XB3 and XA21 in vivo has also been confirmed by coimmunoprecipitation assays .
XB3 contains an ankyrin repeat domain and a RING finger motif that is sufficient for its interaction with the kinase domain of XA21 and for its E3 ubiquitin ligase activity , respectively .
Transgenic plants with reduced expression of the Xb3 gene are compromised in resistance to the avirulent race of X oryzae pv oryzae .
Furthermore , reduced levels of Xb3 lead to decreased levels of the XA21 protein .
These results indicate that Xb3 is necessary for full accumulation of the XA21 protein and for Xa21-mediated resistance . | Matching Sentences: [ Sen. 2, subscore: 2.00 ]: We identified XA21 binding protein 3 ( XB3 ) , an E3 ubiquitin ligase , as a substrate for the XA21 Ser and Thr kinase . [ Sen. 3, subscore: 2.00 ]: The interaction between XB3 and the kinase domain of XA21 has been shown in yeast and in vitro , and the physical association between XB3 and XA21 in vivo has also been confirmed by coimmunoprecipitation assays . [ Sen. 7, subscore: 2.00 ]: These results indicate that Xb3 is necessary for full accumulation of the XA21 protein and for Xa21-mediated resistance . [ Sen. 1, subscore: 1.00 ]: XA21 is a receptor-like kinase protein in rice ( Oryza sativa ) that confers gene-for-gene resistance to specific races of the causal agent of bacterial blight disease , Xanthomonas oryzae pv oryzae . [ Sen. 4, subscore: 1.00 ]: XB3 contains an ankyrin repeat domain and a RING finger motif that is sufficient for its interaction with the kinase domain of XA21 and for its E3 ubiquitin ligase activity , respectively . [ Sen. 6, subscore: 1.00 ]: Furthermore , reduced levels of Xb3 lead to decreased levels of the XA21 protein .
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Score: 9.00 | Title: Rice XB15 , a protein phosphatase 2C , negatively regulates cell death and XA21-mediated innate immunity .
| Author: Park CJ Peng Y Chen X Dardick C Ruan D Bart R Canlas PE Ronald PC | Journal: PLoS Biol Type: MEDLINE | Literature: oryza Field: abstract Doc ID: pub18817453 | Abstract: Perception of extracellular signals by cell surface receptors is of central importance to eukaryotic development and immunity .
Kinases that are associated with the receptors or are part of the receptors themselves modulate signaling through phosphorylation events .
The rice ( Oryza sativa L ) XA21 receptor kinase is a key recognition and signaling determinant in the innate immune response .
A yeast two-hybrid screen using the intracellular portion of XA21 , including the juxtamembrane ( JM ) and kinase domain as bait , identified a protein phosphatase 2C ( PP2C ) , called XA21 binding protein 15 ( XB15 ) .
The interaction of XA21 and XB15 was confirmed in vitro and in vivo by glutathione-S-transferase ( GST ) pull-down and co-immunoprecipitation assays , respectively .
XB15 fusion proteins purified from Escherichia coli and from transgenic rice carry PP2C activity .
Autophosphorylated XA21 can be dephosphorylated by XB15 in a temporal and dosage-dependent manner .
A serine residue in the XA21 JM domain is required for XB15 binding .
Xb15 mutants display a severe cell death phenotype , induction of pathogenesis-related genes , and enhanced XA21-mediated resistance .
Overexpression of Xb15 in an XA21 rice line compromises resistance to the bacterial pathogen Xanthomonas oryzae pv . oryzae .
These results demonstrate that Xb15 encodes a PP2C that negatively regulates the XA21-mediated innate immune response .
| Matching Sentences: [ Sen. 4, subscore: 2.00 ]: A yeast two-hybrid screen using the intracellular portion of XA21 , including the juxtamembrane ( JM ) and kinase domain as bait , identified a protein phosphatase 2C ( PP2C ) , called XA21 binding protein 15 ( XB15 ) . [ Sen. 3, subscore: 1.00 ]: The rice ( Oryza sativa L ) XA21 receptor kinase is a key recognition and signaling determinant in the innate immune response . [ Sen. 5, subscore: 1.00 ]: The interaction of XA21 and XB15 was confirmed in vitro and in vivo by glutathione-S-transferase ( GST ) pull-down and co-immunoprecipitation assays , respectively . [ Sen. 7, subscore: 1.00 ]: Autophosphorylated XA21 can be dephosphorylated by XB15 in a temporal and dosage-dependent manner . [ Sen. 8, subscore: 1.00 ]: A serine residue in the XA21 JM domain is required for XB15 binding . [ Sen. 9, subscore: 1.00 ]: Xb15 mutants display a severe cell death phenotype , induction of pathogenesis-related genes , and enhanced XA21-mediated resistance . [ Sen. 10, subscore: 1.00 ]: Overexpression of Xb15 in an XA21 rice line compromises resistance to the bacterial pathogen Xanthomonas oryzae pv . oryzae . [ Sen. 11, subscore: 1.00 ]: These results demonstrate that Xb15 encodes a PP2C that negatively regulates the XA21-mediated innate immune response .
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Score: 9.00 | Title: Xa21D encodes a receptor-like molecule with a leucine-rich repeat domain that determines race-specific recognition and is subject to adaptive evolution .
| Author: Wang GL Ruan DL Song WY Sideris S Chen L Pi LY Zhang S Zhang Z Fauquet C Gaut BS Whalen MC Ronald PC .
| Journal: Plant Cell Type: ARTICLE | Literature: oryza Field: abstract Doc ID: pub9596635 | Abstract: The rice Xa21 gene confers resistance to Xanthomonas oryzae pv oryzae in a race-specific manner .
Analysis of the inheritance patterns and resistance spectra of transgenic plants carrying six Xa21 gene family members indicated that one member , designated Xa21D , displayed a resistance spectrum identical to that observed for Xa21 but conferred only partial resistance .
Xa21D encodes a receptor-like protein carrying leucine-rich repeat ( LRR ) motifs in the presumed extracellular domain .
The Xa21D transcript terminates shortly after the stop codon introduced by the retrotransposon Retrofit .
Comparison of nucleotide substitutions in the LRR coding regions of Xa21 and Xa21D provided evidence of adaptive selection .
Both functional and evolutionary evidence indicates that the Xa21D LRR domain controls race-specific pathogen recognition . | Matching Sentences: [ Sen. 2, subscore: 3.00 ]: Analysis of the inheritance patterns and resistance spectra of transgenic plants carrying six Xa21 gene family members indicated that one member , designated Xa21D , displayed a resistance spectrum identical to that observed for Xa21 but conferred only partial resistance . [ Sen. 5, subscore: 2.00 ]: Comparison of nucleotide substitutions in the LRR coding regions of Xa21 and Xa21D provided evidence of adaptive selection . [ Sen. 1, subscore: 1.00 ]: The rice Xa21 gene confers resistance to Xanthomonas oryzae pv oryzae in a race-specific manner . [ Sen. 3, subscore: 1.00 ]: Xa21D encodes a receptor-like protein carrying leucine-rich repeat ( LRR ) motifs in the presumed extracellular domain . [ Sen. 4, subscore: 1.00 ]: The Xa21D transcript terminates shortly after the stop codon introduced by the retrotransposon Retrofit . [ Sen. 6, subscore: 1.00 ]: Both functional and evolutionary evidence indicates that the Xa21D LRR domain controls race-specific pathogen recognition .
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Score: 8.00 | Title: Genetic and physical analysis of the rice bacterial blight disease resistance locus , Xa21 .
| Author: Ronald PC Albano B Tabien R Abenes L Wu KS McCouch S Tanksley SD .
| Journal: Mol . Gen . Genet . Type: ARTICLE | Literature: oryza Field: abstract Doc ID: pub1362973 | Abstract: Nearly isogenic lines ( NILs ) of rice ( Oryza sativa ) differing at a locus conferring resistance to the pathogen Xanthomonas oryzae pv . oryzae were surveyed with 123 DNA markers and 985 random primers using restriction fragment length plymorphism ( RFLP ) and random amplified polymorphic DNA ( RAPD ) analysis .
One chromosome 11 marker ( RG103 ) detected polymorphism between the NILs that cosegregated with Xa21 .
All other chromosome 11 DNA markers tested were monomorphic between the NILs , localizing the Xa21 introgressed region to an 8 . 3 cM interval on chromosome 11 .
Furthermore , we identified two polymerase chain reaction ( PCR ) products ( RAPD2148 and RAPD818 ) that detected polymorphisms between the NILs .
Genomic sequences hybridizing with RAPD818 , RAPD248 and RG103 were duplicated specifically in the Xa21 NIL .
All three markers cosegregated with the resistance locus , Xa21 , in a F2 population of 386 progeny .
Based on the frequency with which we recovered polymorphic Xa21-linked markers , we estimated the physical size of the introgressed region to be approximately 800 kb .
This estimation was supported by physical mapping ( using pulsed field gel electrophoresis ) of the sequences hybridizing with the three Xa21-linked DNA markers .
The results showed that the three Xa21-linked markers are physically close to each other , with one copy of the RAPD818 sequences located within 60 kb of RAPD248 and the other copy within 270 kb of RG103 .
None of the enzymes tested generated a DNA fragment that hybridized with all three of the markers indicating that the introgressed region containing the resistance locus Xa21 is probably larger than 270 kb . | Matching Sentences: [ Sen. 2, subscore: 1.00 ]: One chromosome 11 marker ( RG103 ) detected polymorphism between the NILs that cosegregated with Xa21 . [ Sen. 3, subscore: 1.00 ]: All other chromosome 11 DNA markers tested were monomorphic between the NILs , localizing the Xa21 introgressed region to an 8 . 3 cM interval on chromosome 11 . [ Sen. 5, subscore: 1.00 ]: Genomic sequences hybridizing with RAPD818 , RAPD248 and RG103 were duplicated specifically in the Xa21 NIL . [ Sen. 6, subscore: 1.00 ]: All three markers cosegregated with the resistance locus , Xa21 , in a F2 population of 386 progeny . [ Sen. 7, subscore: 1.00 ]: Based on the frequency with which we recovered polymorphic Xa21-linked markers , we estimated the physical size of the introgressed region to be approximately 800 kb . [ Sen. 8, subscore: 1.00 ]: This estimation was supported by physical mapping ( using pulsed field gel electrophoresis ) of the sequences hybridizing with the three Xa21-linked DNA markers . [ Sen. 9, subscore: 1.00 ]: The results showed that the three Xa21-linked markers are physically close to each other , with one copy of the RAPD818 sequences located within 60 kb of RAPD248 and the other copy within 270 kb of RG103 . [ Sen. 10, subscore: 1.00 ]: None of the enzymes tested generated a DNA fragment that hybridized with all three of the markers indicating that the introgressed region containing the resistance locus Xa21 is probably larger than 270 kb .
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Score: 8.00 | Title: Isolation and characterization of rice mutants compromised in Xa21-mediated resistance to X oryzae pv . oryzae .
| Author: Wang GL Wu C Zeng L He C Baraoidan M de Assis Goes da Silva F Williams CE Ronald PC Leung H | Journal: Theor . Appl . Genet . Type: ARTICLE | Literature: oryza Field: abstract Doc ID: pub14523518 | Abstract: The rice gene , Xa21 , confers resistance to diverse races of Xanthomonas oryzae pv . oryzae ( Xoo ) and encodes a receptor-like kinase with leucine-rich repeats in the extra-cellular domain .
To identify genes essential for the function of the Xa21 gene , 4 , 500 IRBB21 ( Xa21 isogenic line in IR24 background ) mutants , induced by diepoxybutane and fast neutrons , were screened against Philippine race six ( PR6 ) Xoo for a change from resistance to susceptibility .
From two greenhouse screens , 23 mutants were identified that had changed from resistant to fully ( 6 ) or partially ( 17 ) susceptible to PR6 .
All fully susceptible mutants carried rearrangements at the Xa21 locus as detected by PCR and Southern hybridization .
For the partially susceptible mutants , no changes were detected at the Xa21 locus based on Southern and PCR analyses .
However , two of these mutants were confirmed via genetic analysis to have mutations at the Xa21 locus .
Partially susceptible mutants exhibited variation in level of susceptibility to different Xoo strains , suggesting that they may carry different mutations required for the Xa21-mediated resistance .
The mutants identified in this study provide useful materials for dissecting the Xa21-mediated resistance pathway in rice . | Matching Sentences: [ Sen. 2, subscore: 2.00 ]: To identify genes essential for the function of the Xa21 gene , 4 , 500 IRBB21 ( Xa21 isogenic line in IR24 background ) mutants , induced by diepoxybutane and fast neutrons , were screened against Philippine race six ( PR6 ) Xoo for a change from resistance to susceptibility . [ Sen. 1, subscore: 1.00 ]: The rice gene , Xa21 , confers resistance to diverse races of Xanthomonas oryzae pv . oryzae ( Xoo ) and encodes a receptor-like kinase with leucine-rich repeats in the extra-cellular domain . [ Sen. 4, subscore: 1.00 ]: All fully susceptible mutants carried rearrangements at the Xa21 locus as detected by PCR and Southern hybridization . [ Sen. 5, subscore: 1.00 ]: For the partially susceptible mutants , no changes were detected at the Xa21 locus based on Southern and PCR analyses . [ Sen. 6, subscore: 1.00 ]: However , two of these mutants were confirmed via genetic analysis to have mutations at the Xa21 locus . [ Sen. 7, subscore: 1.00 ]: Partially susceptible mutants exhibited variation in level of susceptibility to different Xoo strains , suggesting that they may carry different mutations required for the Xa21-mediated resistance . [ Sen. 8, subscore: 1.00 ]: The mutants identified in this study provide useful materials for dissecting the Xa21-mediated resistance pathway in rice .
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Score: 8.00 | Title: Analysis of T-DNA Xa21 loci and bacterial blight resistance effects of the transgene Xa21 in transgenic rice .
| Author: Zhai W Chen C Zhu X Chen X Zhang D Li X Zhu L | Journal: Theor . Appl . Genet . Type: ARTICLE | Literature: oryza Field: abstract Doc ID: pub15088086 | Abstract: The genetic loci and phenotypic effects of the transgene Xa21 , a bacterial blight ( BB ) resistance gene cloned from rice , were investigated in transgenic rice produced through an Agrobacterium-mediated transformation system .
The flanking sequences of integrated T-DNAs were isolated from Xa21 transgenic rice lines using thermal asymmetric interlaced PCR .
Based on the analysis of 24 T-DNA Xa21 flanking sequences , T-DNA loci in rice could be classified into three types : the typical T-DNA integration with the definite left and right borders , the T-DNA integration linked with the adjacent vector backbone sequences and the T-DNA integration involved in a complicated recombination in the flanking sequences .
The T-DNA integration in rice was similar to that in dicotyledonous genomes but was significantly different from the integration produced through direct DNA transformation approaches .
All three types of integrated transgene Xa21 could be stably inherited and expressed the BB resistance through derived generations in their respective transgenic lines .
The flanking sequences of the typical T-DNA integration consisted of actual rice genomic DNA and could be used as probes to locate the transgene on the rice genetic map .
A total of 15 different rice T-DNA flanking sequences were identified .
They displayed restriction fragment length polymorphisms ( RFLPs ) between two rice varieties , ZYQ8 and JX17 , and were mapped on rice chromosomes 1 , 3 , 4 , 5 , 7 , 9 , 10 , 11 and 12 , respectively , by using a double haploid population derived from a cross between ZYQ8 and JX17 .
The blast search and homology comparison of the rice T-DNA flanking sequences with the rice chromosome-anchored sequence database confirmed the RFLP mapping results .
On the basis of genetic mapping of the T-DNA Xa21 loci , the BB resistance effects of the transgene Xa21 at different chromosome locations were investigated using homozygous transgenic lines with only one copy of the transgene .
Among the transgenic lines , no obvious position effects of the transgene Xa21 were observed .
In addition , the BB resistance levels of the Xa21 transgenic plants with different transgene copy numbers and on different genetic backgrounds were also investigated .
It was observed that genetic background ( or genome ) effects were more obvious than dosage effects and position effects on the BB resistance level of the transgenic plants . | Matching Sentences: [ Sen. 10, subscore: 2.00 ]: On the basis of genetic mapping of the T-DNA Xa21 loci , the BB resistance effects of the transgene Xa21 at different chromosome locations were investigated using homozygous transgenic lines with only one copy of the transgene . [ Sen. 1, subscore: 1.00 ]: The genetic loci and phenotypic effects of the transgene Xa21 , a bacterial blight ( BB ) resistance gene cloned from rice , were investigated in transgenic rice produced through an Agrobacterium-mediated transformation system . [ Sen. 2, subscore: 1.00 ]: The flanking sequences of integrated T-DNAs were isolated from Xa21 transgenic rice lines using thermal asymmetric interlaced PCR . [ Sen. 3, subscore: 1.00 ]: Based on the analysis of 24 T-DNA Xa21 flanking sequences , T-DNA loci in rice could be classified into three types : the typical T-DNA integration with the definite left and right borders , the T-DNA integration linked with the adjacent vector backbone sequences and the T-DNA integration involved in a complicated recombination in the flanking sequences . [ Sen. 5, subscore: 1.00 ]: All three types of integrated transgene Xa21 could be stably inherited and expressed the BB resistance through derived generations in their respective transgenic lines . [ Sen. 11, subscore: 1.00 ]: Among the transgenic lines , no obvious position effects of the transgene Xa21 were observed . [ Sen. 12, subscore: 1.00 ]: In addition , the BB resistance levels of the Xa21 transgenic plants with different transgene copy numbers and on different genetic backgrounds were also investigated .
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Score: 8.00 | Title: Elucidation of XA21-mediated innate immunity .
| Author: Park CJ Han SW Chen X Ronald PC | Journal: Cell Microbiol Type: MEDLINE | Literature: oryza Field: abstract Doc ID: pub20590657 | Abstract: In the early 1970s , the Xa21 gene from the wild rice species Oryza longistaminata drew attention of rice breeders because of its broad-spectrum resistance to diverse strains of a serious bacterial disease of rice in Asia and Africa , called bacterial blight disease , caused by the Gram-negative bacterium , Xanthomonas oryzae pv . oryzae ( Xoo ) .
In 1995 , we isolated the gene controlling this resistance and in 2009 demonstrated that XA21 recognizes a highly conserved peptide , called Ax21 ( activator of XA21-mediated immunity ) .
Tyrosine sulfation of Ax21 is required for recognition by rice XA21 .
A decade of genetic , molecular and biochemical studies have uncovered key components of the XA21-mediated signalling cascade .
Ax21 recognition by XA21 at the cell surface induces phosphorylation-mediated events , which are predicted to alter subcellular localization and/or DNA-binding activity of a WRKY family of transcription factors .
Because XA21 is representative of the large number of predicted pattern recognition receptors ( PRRs ) in rice ( n = 328 ) , Arabidopsis ( n = 35 ) and other plant species , further characterization of XA21-mediated signalling pathways will contribute to elucidation of these important defence responses .
| Matching Sentences: [ Sen. 2, subscore: 2.00 ]: In 1995 , we isolated the gene controlling this resistance and in 2009 demonstrated that XA21 recognizes a highly conserved peptide , called Ax21 ( activator of XA21-mediated immunity ) . [ Sen. 6, subscore: 2.00 ]: Because XA21 is representative of the large number of predicted pattern recognition receptors ( PRRs ) in rice ( n = 328 ) , Arabidopsis ( n = 35 ) and other plant species , further characterization of XA21-mediated signalling pathways will contribute to elucidation of these important defence responses . [ Sen. 1, subscore: 1.00 ]: In the early 1970s , the Xa21 gene from the wild rice species Oryza longistaminata drew attention of rice breeders because of its broad-spectrum resistance to diverse strains of a serious bacterial disease of rice in Asia and Africa , called bacterial blight disease , caused by the Gram-negative bacterium , Xanthomonas oryzae pv . oryzae ( Xoo ) . [ Sen. 3, subscore: 1.00 ]: Tyrosine sulfation of Ax21 is required for recognition by rice XA21 . [ Sen. 4, subscore: 1.00 ]: A decade of genetic , molecular and biochemical studies have uncovered key components of the XA21-mediated signalling cascade . [ Sen. 5, subscore: 1.00 ]: Ax21 recognition by XA21 at the cell surface induces phosphorylation-mediated events , which are predicted to alter subcellular localization and/or DNA-binding activity of a WRKY family of transcription factors .
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Score: 7.00 | Title: Short communication : developmental control of Xa21-mediated disease resistance in rice .
| Author: Century KS Lagman RA Adkisson M Morlan J Tobias R Schwartz K Smith A Love J Ronald PC Whalen MC .
| Journal: Plant J Type: ARTICLE | Literature: oryza Field: abstract Doc ID: pub10571882 | Abstract: The rice resistance gene Xa21 confers resistance against the bacterial pathogen Xanthomonas oryzae pv . oryzae ( Xoo ) .
The molecular genetic mechanism controlling the integration of the Xa21-mediated disease resistance response with the developmental program in rice is under study in this model system .
Reproducible means of infecting plants at certain developmental stages were designed based on the timing of full expansion of the leaf .
Xa21-resistance progressively increases from the susceptible juvenile leaf 2 stage through later stages , with 100% resistance at the adult leaf 9/10 stage .
We found that Xa21 expression is independent of plant developmental stage , infection with Xoo , or wounding .
Expression of the Xa21 gene transcript is not correlated with expression of Xa21 disease resistance indicating that the developmental regulation of Xa21-resistance is either controlled post-transcriptionally or by other factors . | Matching Sentences: [ Sen. 6, subscore: 3.00 ]: Expression of the Xa21 gene transcript is not correlated with expression of Xa21 disease resistance indicating that the developmental regulation of Xa21-resistance is either controlled post-transcriptionally or by other factors . [ Sen. 1, subscore: 1.00 ]: The rice resistance gene Xa21 confers resistance against the bacterial pathogen Xanthomonas oryzae pv . oryzae ( Xoo ) . [ Sen. 2, subscore: 1.00 ]: The molecular genetic mechanism controlling the integration of the Xa21-mediated disease resistance response with the developmental program in rice is under study in this model system . [ Sen. 4, subscore: 1.00 ]: Xa21-resistance progressively increases from the susceptible juvenile leaf 2 stage through later stages , with 100% resistance at the adult leaf 9/10 stage . [ Sen. 5, subscore: 1.00 ]: We found that Xa21 expression is independent of plant developmental stage , infection with Xoo , or wounding .
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Score: 7.00 | Title: The autophosphorylated Ser686 , Thr688 , and Ser689 residues in the intracellular juxtamembrane domain of XA21 are implicated in stability control of rice receptor-like kinase .
| Author: Xu WH Wang YS Liu GZ Chen X Tinjuangjun P Pi LY Song WY .
| Journal: Plant J Type: ARTICLE | Literature: oryza Field: abstract Doc ID: pub16460508 | Abstract: The rice gene Xa21 confers resistance against Xanthomonas oryzae pv . oryzae ( Xoo ) .
Xa21 encodes a receptor-like kinase ( XA21 ) .
We demonstrate that XA21 autophosphorylates residues Ser686 , Thr688 and Ser689 in vitro .
Substitution of these residues with alanines did not affect the autophosphorylation function of this kinase , but specifically destabilized the resistance protein in vitro and in vivo .
Plants carrying these same substitutions in XA21 were compromised in their resistance to the normally avirulent Xoo Philippine race 6 .
Additionally , we show that wild-type XA21 and the kinase-dead mutant with the invariable Lys736 residue mutated to glutamic acid were also proteolytically degraded in protein extracts .
Finally , we show a correlation between the in vitro degradation and in vivo instability of the proteins .
We propose that autophosphorylation of Ser686 , Thr688 and Ser689 functions to stabilize XA21 against the developmentally controlled proteolytic activity . | Matching Sentences: [ Sen. 2, subscore: 2.00 ]: Xa21 encodes a receptor-like kinase ( XA21 ) . [ Sen. 1, subscore: 1.00 ]: The rice gene Xa21 confers resistance against Xanthomonas oryzae pv . oryzae ( Xoo ) . [ Sen. 3, subscore: 1.00 ]: We demonstrate that XA21 autophosphorylates residues Ser686 , Thr688 and Ser689 in vitro . [ Sen. 5, subscore: 1.00 ]: Plants carrying these same substitutions in XA21 were compromised in their resistance to the normally avirulent Xoo Philippine race 6 . [ Sen. 6, subscore: 1.00 ]: Additionally , we show that wild-type XA21 and the kinase-dead mutant with the invariable Lys736 residue mutated to glutamic acid were also proteolytically degraded in protein extracts . [ Sen. 8, subscore: 1.00 ]: We propose that autophosphorylation of Ser686 , Thr688 and Ser689 functions to stabilize XA21 against the developmentally controlled proteolytic activity .
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Score: 7.00 | Title: Ectopic expression of rice Xa21 overcomes developmentally controlled resistance to Xanthomonas oryzae pv . oryzae .
| Author: Park CJ Lee SW Chern M Sharma R Canlas PE Song MY Jeon JS Ronald PC | Journal: Plant Sci Type: In-Data-Review | Literature: oryza Field: abstract Doc ID: pub21076626 | Abstract: Recognition of pathogen-associated molecular patterns ( PAMPs ) by pattern recognition receptors ( PRRs ) activates the innate immune response .
The rice PRR , XA21 , confers robust resistance at adult stages to most strains of the bacterial pathogen Xanthomonas oryzae pv . oryzae ( Xoo ) .
Seedlings are still easily infected by Xoo , causing severe yield losses .
Here we report that Xa21 is induced by Xoo infection and that ectopic expression of Xa21 confers resistance at three leaf stage ( three-week-old ) , overcoming the developmental limitation of XA21-mediated resistance .
Ectopic expression of Xa21 also up-regulates a larger set of defense-related genes as compared to Xa21 driven by the native promoter .
These results indicate that altered regulation of Xa21 expression is useful for developing enhanced resistance to Xoo at multiple developmental stages .
| Matching Sentences: [ Sen. 4, subscore: 3.00 ]: Here we report that Xa21 is induced by Xoo infection and that ectopic expression of Xa21 confers resistance at three leaf stage ( three-week-old ) , overcoming the developmental limitation of XA21-mediated resistance . [ Sen. 5, subscore: 2.00 ]: Ectopic expression of Xa21 also up-regulates a larger set of defense-related genes as compared to Xa21 driven by the native promoter . [ Sen. 2, subscore: 1.00 ]: The rice PRR , XA21 , confers robust resistance at adult stages to most strains of the bacterial pathogen Xanthomonas oryzae pv . oryzae ( Xoo ) . [ Sen. 6, subscore: 1.00 ]: These results indicate that altered regulation of Xa21 expression is useful for developing enhanced resistance to Xoo at multiple developmental stages .
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Score: 6.00 | Title: [ Accelerated improvement of bacterial blight resistance of Shuhui527 using molecular marker-assisted selection ] | Author: Huang TY Li SG Wang YP Li HY .
| Journal: Sheng Wu Gong Cheng Xue Bao Type: ARTICLE | Literature: oryza Field: abstract Doc ID: pub15966313 | Abstract: Shuhui527 is a promising restorer line bred by Rice Research Institute of Sichuan Agricultural University in recent years .
However , this line is susceptible to Bacterial Blight ( BB ) , which limits its use .
The IRBB60 , from the International Rice Research Institute ( IRRI ) , contains dominant genes Xa21 and Xa4 conferring resistance to BB .
The objective of this study is to improve the BB resistance of Shuhui527 by introgressing Xa21 and Xa4 , the two broad-spectrum BB resistance genes , into Shuhui527 with IRBB60 as the donor , pTA248 and MP12 , linking tightly with Xa21 and Xa4 respectively as DNA markers .
BC1 F1 progenies of ( Shuhui527 x IRBB60 ) , containing Xa21 and Xa4 identified using PCR screening and with agronomic traits including plant type , grain type and days to heading etc similar to those of Shuhui527 , were subsequently backcrossed to Shuhui527 and self-pollinated to generate BC2 F1 and BC1 F2 . The BC3 F1 and BC3 F2 were subsequently developed using the same approach .
Among the 20 BC3 F2 plants , homozygous Xa21 and Xa4 , 10 plants were the most similar to Shuhui527 in the agronomic traits , and were screened using 120 pairs SSR and 100 pairs RAPD markers .
Based on the results of the background screening and the performance of the agronomic traits , 5 plants were identified as improved-Shuhui527 and designated as 527R-5 , 527R-6 , 527R-8 , 527R-9 and 527R-10 .
The improved- Shuhui527 lines expressed high resistance to Xanthomonas oryzae pv . oryzae ( Xoo ) stains C I - C VII , P1 and P6 .
The evaluation of the polymorphisms and selection accuracies of pTA248 and MP12 demonstrated that the polymorphisms of the two markers were obvious and co-dominant and the accuracies were more than 97% and 83% respectively , indicating the two markers are good for Xa21 and Xa4 in Molecular Marker-assisted Selection .
| Matching Sentences: [ Sen. 4, subscore: 2.00 ]: The objective of this study is to improve the BB resistance of Shuhui527 by introgressing Xa21 and Xa4 , the two broad-spectrum BB resistance genes , into Shuhui527 with IRBB60 as the donor , pTA248 and MP12 , linking tightly with Xa21 and Xa4 respectively as DNA markers . [ Sen. 3, subscore: 1.00 ]: The IRBB60 , from the International Rice Research Institute ( IRRI ) , contains dominant genes Xa21 and Xa4 conferring resistance to BB . [ Sen. 5, subscore: 1.00 ]: BC1 F1 progenies of ( Shuhui527 x IRBB60 ) , containing Xa21 and Xa4 identified using PCR screening and with agronomic traits including plant type , grain type and days to heading etc similar to those of Shuhui527 , were subsequently backcrossed to Shuhui527 and self-pollinated to generate BC2 F1 and BC1 F2 . The BC3 F1 and BC3 F2 were subsequently developed using the same approach . [ Sen. 6, subscore: 1.00 ]: Among the 20 BC3 F2 plants , homozygous Xa21 and Xa4 , 10 plants were the most similar to Shuhui527 in the agronomic traits , and were screened using 120 pairs SSR and 100 pairs RAPD markers . [ Sen. 9, subscore: 1.00 ]: The evaluation of the polymorphisms and selection accuracies of pTA248 and MP12 demonstrated that the polymorphisms of the two markers were obvious and co-dominant and the accuracies were more than 97% and 83% respectively , indicating the two markers are good for Xa21 and Xa4 in Molecular Marker-assisted Selection .
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Score: 6.00 | Title: Epigenetic inheritance in rice plants .
| Author: Akimoto K Katakami H Kim HJ Ogawa E Sano CM Wada Y Sano H | Journal: Ann Bot ( Lond ) Type: MEDLINE | Literature: oryza Field: abstract Doc ID: pub17576658 | Abstract: BACKGROUND AND AIMS : Epigenetics is defined as mechanisms that regulate gene expression without base sequence alteration .
One molecular basis is considered to be DNA cytosine methylation , which reversibly modifies DNA or chromatin structures .
Although its correlation with epigenetic inheritance over generations has been circumstantially shown , evidence at the gene level has been limited .
The present study aims to find genes whose methylation status directly correlates with inheritance of phenotypic changes .
METHODS : DNA methylation in vivo was artificially reduced by treating rice ( Oryza sativa ssp . japonica ) seeds with 5-azadeoxycytidine , and the progeny were cultivated in the field for > 10 years .
Genomic regions with changed methylation status were screened by the methylation-sensitive amplified polymorphysm ( MSAP ) method , and cytosine methylation was directly scanned by the bisulfite mapping method .
Pathogen infection with Xanthomonas oryzae pv . oryzae , race PR2 was performed by the scissors-dip method on mature leaf blades .
KEY RESULTS : The majority of seedlings were lethal , but some survived to maturity .
One line designated as Line-2 showed a clear marker phenotype of dwarfism , which was stably inherited by the progeny over nine generations .
MSAP screening identified six fragments , among which two were further characterized by DNA blot hybridization and direct methylation mapping .
One clone encoding a retrotransposon gag-pol polyprotein showed a complete erasure of 5-methylcytosines in Line-2 , but neither translocation nor expression of this region was detectable .
The other clone encoded an Xa21-like protein , Xa21G .
In wild-type plants , all cytosines were methylated within the promoter region , whereas in Line-2 , corresponding methylation was completely erased throughout generations .
Expression of Xa21G was not detectable in wild type but was constitutive in Line-2 .
When infected with X oryzae pv . oryzae , against which Xa21 confers resistance in a gene-for-gene manner , the progeny of Line-2 were apparently resistant while the wild type was highly susceptible without Xa21G expression .
CONCLUSIONS : These results indicated that demethylation was selective in Line-2 , and that promoter demethylation abolished the constitutive silencing of Xa21G due to hypermethylation , resulting in acquisition of disease resistance .
Both hypomethylation and resistant trait were stably inherited .
This is a clear example of epigenetic inheritance , and supports the idea of Lamarckian inheritance which suggested acquired traits to be heritable .
| Matching Sentences: [ Sen. 12, subscore: 2.00 ]: The other clone encoded an Xa21-like protein , Xa21G . [ Sen. 15, subscore: 2.00 ]: When infected with X oryzae pv . oryzae , against which Xa21 confers resistance in a gene-for-gene manner , the progeny of Line-2 were apparently resistant while the wild type was highly susceptible without Xa21G expression . [ Sen. 14, subscore: 1.00 ]: Expression of Xa21G was not detectable in wild type but was constitutive in Line-2 . [ Sen. 16, subscore: 1.00 ]: CONCLUSIONS : These results indicated that demethylation was selective in Line-2 , and that promoter demethylation abolished the constitutive silencing of Xa21G due to hypermethylation , resulting in acquisition of disease resistance .
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Score: 6.00 | Title: [ Expression and autophosphorylation analysis of XA21 and PI-D2 protein kinases in Saccharomyces cerevisiae ] | Author: Wang SL Li LY Shang JJ Wang J Liu GZ | Journal: Wei Sheng Wu Xue Bao Type: In-Process | Literature: oryza Field: abstract Doc ID: pub18271255 | Abstract: Rice bacterial blight and blast are the most crucial rice disease .
Xa21 confers resistance to bacterial blight , while Pi-d2 confers resistance to rice blast Both Xa21 and Pi-d2 encode receptor kinase-like proteins .
Biochemical properties of XA21 kinase expressed in bacterial were characterized in our previous report .
In this study , both XA21 and PI-D2 kinase domain were PCR amplified and cloned into yeast expression vector pEGH via recombinational cloning strategy , kinase proteins expressed in eukaryotic yeast system was purified and autophosphorylation assay was carried out .
The results indicated that XA21 and PI-D2 protein can be detected by SDS-PAGE and showed expected molecular weight .
Autophosphorylation assay indicated that yeast expressed XA21 and PI-D2 were active when incubated with P32 labelled ATP .
The experiment provided basic materials for biochemical prosperity analysis , protein-protein interaction and substrate screening research .
| Matching Sentences: [ Sen. 2, subscore: 2.00 ]: Xa21 confers resistance to bacterial blight , while Pi-d2 confers resistance to rice blast Both Xa21 and Pi-d2 encode receptor kinase-like proteins . [ Sen. 3, subscore: 1.00 ]: Biochemical properties of XA21 kinase expressed in bacterial were characterized in our previous report . [ Sen. 4, subscore: 1.00 ]: In this study , both XA21 and PI-D2 kinase domain were PCR amplified and cloned into yeast expression vector pEGH via recombinational cloning strategy , kinase proteins expressed in eukaryotic yeast system was purified and autophosphorylation assay was carried out . [ Sen. 5, subscore: 1.00 ]: The results indicated that XA21 and PI-D2 protein can be detected by SDS-PAGE and showed expected molecular weight . [ Sen. 6, subscore: 1.00 ]: Autophosphorylation assay indicated that yeast expressed XA21 and PI-D2 were active when incubated with P32 labelled ATP .
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Score: 6.00 | Title: Dissection of the factors affecting development-controlled and race-specific disease resistance conferred by leucine-rich repeat receptor kinase-type R genes in rice .
| Author: Zhao J Fu J Li X Xu C Wang S | Journal: Theor Appl Genet Type: Publisher | Literature: oryza Field: abstract Doc ID: pub19390838 | Abstract: Development-controlled resistance and resistance specificity frequently restrict the application of a disease resistance ( R ) gene in crop breeding programs .
Xa3/Xa26 and Xa21 , encoding leucine-rich repeat ( LRR ) -kinase type plasma membrane proteins , mediate race-specific resistance to Xanthomonas oryzae pv . oryzae ( Xoo ) , which causes bacterial blight , one of the most devastating rice diseases .
Plants carrying Xa3/Xa26 and plants carrying Xa21 have different resistance spectra and the functions of the two R genes are regulated by developmental stage .
Four chimeric genes encoding proteins consisting of different parts of XA3/XA26 and XA21 were constructed by domain swapping and transformed into a susceptible rice variety .
The resistance spectra and development-regulated resistance of the transgenic plants carrying Xa3/Xa26 , Xa21 , or chimeric gene to different Xoo strains were analyzed in the same genetic background .
The results suggest that the gradually increased expression of Xa3/Xa26 and Xa21 plays an important role in the progressively enhanced Xoo resistance during rice development .
In addition , the LRR domains of XA3/XA26 and XA21 are important determinants of race-specific recognition during rice-Xoo interaction , but juxtamembrane regions of the two R proteins also appear to contribute to resistance specificity .
| Matching Sentences: [ Sen. 2, subscore: 1.00 ]: Xa3/Xa26 and Xa21 , encoding leucine-rich repeat ( LRR ) -kinase type plasma membrane proteins , mediate race-specific resistance to Xanthomonas oryzae pv . oryzae ( Xoo ) , which causes bacterial blight , one of the most devastating rice diseases . [ Sen. 3, subscore: 1.00 ]: Plants carrying Xa3/Xa26 and plants carrying Xa21 have different resistance spectra and the functions of the two R genes are regulated by developmental stage . [ Sen. 4, subscore: 1.00 ]: Four chimeric genes encoding proteins consisting of different parts of XA3/XA26 and XA21 were constructed by domain swapping and transformed into a susceptible rice variety . [ Sen. 5, subscore: 1.00 ]: The resistance spectra and development-regulated resistance of the transgenic plants carrying Xa3/Xa26 , Xa21 , or chimeric gene to different Xoo strains were analyzed in the same genetic background . [ Sen. 6, subscore: 1.00 ]: The results suggest that the gradually increased expression of Xa3/Xa26 and Xa21 plays an important role in the progressively enhanced Xoo resistance during rice development . [ Sen. 7, subscore: 1.00 ]: In addition , the LRR domains of XA3/XA26 and XA21 are important determinants of race-specific recognition during rice-Xoo interaction , but juxtamembrane regions of the two R proteins also appear to contribute to resistance specificity .
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Score: 6.00 | Title: Overexpression of the endoplasmic reticulum chaperone BiP3 regulates XA21-mediated innate immunity in rice .
| Author: Park CJ Bart R Chern M Canlas PE Bai W Ronald PC | Journal: PLoS One Type: MEDLINE | Literature: oryza Field: abstract Doc ID: pub20174657 | Abstract: Recognition of pathogen-associated molecular patterns by pattern recognition receptors ( PRRs ) activates the innate immune response .
Although PRR-mediated signaling events are critical to the survival of plants and animals , secretion and localization of PRRs have not yet been clearly elucidated .
Here we report the in vivo interaction of the endoplasmic reticulum ( ER ) chaperone BiP3 with the rice XA21 PRR , which confers resistance to the Gram negative bacterium , Xanthomonas oryzae pv . oryzae ( Xoo ) .
We show that XA21 is glycosylated and is primarily localized to the ER and also to the plasma membrane ( PM ) .
In BiP3-overexpressing rice plants , XA21-mediated immunity is compromised , XA21 stability is significantly decreased , and XA21 proteolytic cleavage is inhibited .
BiP3 overexpression does not affect the general rice defense response , cell death or brassinolide-induced responses .
These results indicate that BiP3 regulates XA21 protein stability and processing and that this regulation is critical for resistance to Xoo .
| Matching Sentences: [ Sen. 5, subscore: 3.00 ]: In BiP3-overexpressing rice plants , XA21-mediated immunity is compromised , XA21 stability is significantly decreased , and XA21 proteolytic cleavage is inhibited . [ Sen. 3, subscore: 1.00 ]: Here we report the in vivo interaction of the endoplasmic reticulum ( ER ) chaperone BiP3 with the rice XA21 PRR , which confers resistance to the Gram negative bacterium , Xanthomonas oryzae pv . oryzae ( Xoo ) . [ Sen. 4, subscore: 1.00 ]: We show that XA21 is glycosylated and is primarily localized to the ER and also to the plasma membrane ( PM ) . [ Sen. 7, subscore: 1.00 ]: These results indicate that BiP3 regulates XA21 protein stability and processing and that this regulation is critical for resistance to Xoo .
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Score: 5.00 | Title: [ Generation of selectable marker-free and vector backbone sequence-free Xa21 transgenic rice ] | Author: Xia ZH Li XB Chen CY Fan HK Jiang GH Zhu LH Zhai WX .
| Journal: Sheng Wu Gong Cheng Xue Bao Type: ARTICLE | Literature: oryza Field: abstract Doc ID: pub16607944 | Abstract: The dominant gene Xa21 with broad-spectrum and high resistance to Xanthomonas oryzae pv . oryzae ( Xoo ) was transferred into C418 , an important restorer line of japonica hybrid rice in China using double right-border ( DRB ) T-DNA binary vector through Agrobacterium-mediated transformation .
17 transgenic lines were Xa21-positive with high resistance to the race P6 of Xoo through PCR analysis and resistance identification , among the total 27 independent primary transformants ( T0 ) obtained .
The subsequent analysis of the T1 progenies of these 17 T0 lines through PCR-assisted selection and resistance investigation showed that four Xa21 transgenic T0 lines could produce selectable marker-free ( SMF ) progenies .
The frequency of primary transformants producing SMF progenies was 15% .
In addition , PCR analysis also revealed these SMF progenies did not contain vector backbone sequence , and they were named as SMF and vector backbone sequence-free ( SMF-VBSF ) Xa21 transgenic plants .
The further molecular and phenotypic analysis of the T2 and T3 progenies testified the homozygous SMF-VBSF Xa21 transgenic plants were obtained with high resistance to Xoo .
| Matching Sentences: [ Sen. 1, subscore: 1.00 ]: The dominant gene Xa21 with broad-spectrum and high resistance to Xanthomonas oryzae pv . oryzae ( Xoo ) was transferred into C418 , an important restorer line of japonica hybrid rice in China using double right-border ( DRB ) T-DNA binary vector through Agrobacterium-mediated transformation . [ Sen. 2, subscore: 1.00 ]: 17 transgenic lines were Xa21-positive with high resistance to the race P6 of Xoo through PCR analysis and resistance identification , among the total 27 independent primary transformants ( T0 ) obtained . [ Sen. 3, subscore: 1.00 ]: The subsequent analysis of the T1 progenies of these 17 T0 lines through PCR-assisted selection and resistance investigation showed that four Xa21 transgenic T0 lines could produce selectable marker-free ( SMF ) progenies . [ Sen. 5, subscore: 1.00 ]: In addition , PCR analysis also revealed these SMF progenies did not contain vector backbone sequence , and they were named as SMF and vector backbone sequence-free ( SMF-VBSF ) Xa21 transgenic plants . [ Sen. 6, subscore: 1.00 ]: The further molecular and phenotypic analysis of the T2 and T3 progenies testified the homozygous SMF-VBSF Xa21 transgenic plants were obtained with high resistance to Xoo .
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Score: 5.00 | Title: [ Advances of rice bacterial blight disease resistance gene Xa21 ] | Author: Bai H Li LY Liu GZ .
| Journal: Yi Chuan Type: ARTICLE | Literature: oryza Field: abstract Doc ID: pub16818441 | Abstract: Gene Xa21 is the first disease resistance gene cloned from rice ( Oryza sativa L ) , which encodes a receptor-like kinase and confers broad spectrum resistance against Xanthomonas oryzae pv . oryzae ( Xoo ) .
In this paper , the discovery , mapping and cloning of Xa21 were reviewed briefly .
The molecular mechanism of resistance and its breeding application , including biochemical properties of the kinase domain of XA21 , AvrXa21 identification , the disease resistance pathway mediated by Xa21 , and the mechanism of disease resistance were summarized .
Future perspective on Xa21-related research is also discussed . | Matching Sentences: [ Sen. 3, subscore: 2.00 ]: The molecular mechanism of resistance and its breeding application , including biochemical properties of the kinase domain of XA21 , AvrXa21 identification , the disease resistance pathway mediated by Xa21 , and the mechanism of disease resistance were summarized . [ Sen. 1, subscore: 1.00 ]: Gene Xa21 is the first disease resistance gene cloned from rice ( Oryza sativa L ) , which encodes a receptor-like kinase and confers broad spectrum resistance against Xanthomonas oryzae pv . oryzae ( Xoo ) . [ Sen. 2, subscore: 1.00 ]: In this paper , the discovery , mapping and cloning of Xa21 were reviewed briefly . [ Sen. 4, subscore: 1.00 ]: Future perspective on Xa21-related research is also discussed .
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Score: 5.00 | Title: An ATPase promotes autophosphorylation of the pattern recognition receptor XA21 and inhibits XA21-mediated immunity .
| Author: Chen X Chern M Canlas PE Ruan D Jiang C Ronald PC | Journal: Proc Natl Acad Sci U S A Type: MEDLINE | Literature: oryza Field: abstract Doc ID: pub20385831 | Abstract: Cell-surface pattern recognition receptors ( PRRs ) are key components of the innate immune response in animals and plants .
These receptors typically carry or associate with non-RD kinases to control early events of innate immunity signaling .
Despite their importance , the mode of regulation of PRRs is largely unknown .
Here we show that the rice PRR , XA21 , interacts with XA21 binding protein 24 ( XB24 ) , a previously undescribed ATPase .
XB24 promotes autophosphorylation of XA21 through its ATPase activity .
Rice lines silenced for Xb24 display enhanced XA21-mediated immunity , whereas rice lines overexpressing XB24 are compromised for immunity .
XB24 ATPase enzyme activity is required for XB24 function .
XA21 is degraded in the presence of the pathogen-associated molecular pattern Ax21 when XB24 is overexpressed .
These results demonstrate a function for this large class of broadly conserved ATPases in PRR-mediated immunity .
| Matching Sentences: [ Sen. 4, subscore: 2.00 ]: Here we show that the rice PRR , XA21 , interacts with XA21 binding protein 24 ( XB24 ) , a previously undescribed ATPase . [ Sen. 5, subscore: 1.00 ]: XB24 promotes autophosphorylation of XA21 through its ATPase activity . [ Sen. 6, subscore: 1.00 ]: Rice lines silenced for Xb24 display enhanced XA21-mediated immunity , whereas rice lines overexpressing XB24 are compromised for immunity . [ Sen. 8, subscore: 1.00 ]: XA21 is degraded in the presence of the pathogen-associated molecular pattern Ax21 when XB24 is overexpressed .
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Score: 5.00 | Title: Transcriptional characteristics of Xa21-mediated defense responses in rice .
| Author: Gan Q Bai H Zhao X Tao Y Zeng H Han Y Song W Zhu L Liu G | Journal: J Integr Plant Biol Type: MEDLINE | Literature: oryza Field: abstract Doc ID: pub21324061 | Abstract: Bacterial blight , caused by Xanthomonas oryzae pv . oryzae ( Xoo ) , is the most destructive bacterial disease of rice .
The cloned rice gene Xa21 confers resistance to a broad spectrum of Xoo races .
To identify genes involved in Xa21-mediated immunity , a whole-genome oligonucleotide microarray of rice was used to profile the expression of rice genes between incompatible interactions and mock treatments at 0 , 4 , 8 , 24 , 72 and 120 h post inoculation ( hpi ) or between incompatible and compatible interactions at 4 hpi , respectively .
A total of 441 differentially expressed genes , designated as XDGs ( Xa21 mediated differentially expressed genes ) , were identified .
Based on their functional annotations , the XDGs were assigned to 14 categories , including defense-related , signaling , transcriptional regulators .
Most of the defense-related genes belonged to the pathogenesis-related gene family , which was induced dramatically at 72 and 120 hpi .
Interestingly , most signaling and transcriptional regulator genes were downregulated at 4 and 8 hpi , suggesting that negative regulation of cellular signaling may play a role in the Xa21-mediated defense response .
Comparison of expression profiles between Xa21 and other R gene-mediated defense systems revealed interesting common responses .
Representative XDGs with supporting evidences were also discussed .
| Matching Sentences: [ Sen. 2, subscore: 1.00 ]: The cloned rice gene Xa21 confers resistance to a broad spectrum of Xoo races . [ Sen. 3, subscore: 1.00 ]: To identify genes involved in Xa21-mediated immunity , a whole-genome oligonucleotide microarray of rice was used to profile the expression of rice genes between incompatible interactions and mock treatments at 0 , 4 , 8 , 24 , 72 and 120 h post inoculation ( hpi ) or between incompatible and compatible interactions at 4 hpi , respectively . [ Sen. 4, subscore: 1.00 ]: A total of 441 differentially expressed genes , designated as XDGs ( Xa21 mediated differentially expressed genes ) , were identified . [ Sen. 7, subscore: 1.00 ]: Interestingly , most signaling and transcriptional regulator genes were downregulated at 4 and 8 hpi , suggesting that negative regulation of cellular signaling may play a role in the Xa21-mediated defense response . [ Sen. 8, subscore: 1.00 ]: Comparison of expression profiles between Xa21 and other R gene-mediated defense systems revealed interesting common responses .
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Score: 5.00 | Title: Cleavage and nuclear localization of the rice XA21 immune receptor .
| Author: Park CJ Ronald PC | Journal: Nat Commun Type: In-Data-Review | Literature: oryza Field: abstract Doc ID: pub22735448 | Abstract: Plants and animals carry specific receptors that recognize invading pathogens and respond by activating an immune response .
The rice XA21 receptor confers broad-spectrum immunity to the Gram-negative bacterial pathogen , Xanthomonas oryzae pv . oryzae upon recognition of a small protein , Ax21 , that is conserved in all Xanthomonas species and related genera .
Here we demonstrate that XA21 is cleaved to release the intracellular kinase domain and that this intracellular domain carries a functional nuclear localization sequence .
Bimolecular fluorescence complementation assays indicate that the XA21 intracellular domain interacts with the OsWRKY62 transcriptional regulator exclusively in the nucleus of rice protoplasts .
In vivo cleavage of XA21 and translocalization of the intracellular kinase domain to the nucleus is required for the XA21-mediated immune response .
These results suggest a new model for immune receptor function : on receptor recognition of conserved microbial signatures , the associated kinase translocates to the nucleus where it directly interacts with transcriptional regulators .
| Matching Sentences: [ Sen. 5, subscore: 2.00 ]: In vivo cleavage of XA21 and translocalization of the intracellular kinase domain to the nucleus is required for the XA21-mediated immune response . [ Sen. 2, subscore: 1.00 ]: The rice XA21 receptor confers broad-spectrum immunity to the Gram-negative bacterial pathogen , Xanthomonas oryzae pv . oryzae upon recognition of a small protein , Ax21 , that is conserved in all Xanthomonas species and related genera . [ Sen. 3, subscore: 1.00 ]: Here we demonstrate that XA21 is cleaved to release the intracellular kinase domain and that this intracellular domain carries a functional nuclear localization sequence . [ Sen. 4, subscore: 1.00 ]: Bimolecular fluorescence complementation assays indicate that the XA21 intracellular domain interacts with the OsWRKY62 transcriptional regulator exclusively in the nucleus of rice protoplasts .
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Score: 4.00 | Title: [ Genetic mapping of T-DNA integration sites in Xa21 transgenic rice ] | Author: Zhu XF Chen XW Li XB Qian Q Huang DN Zhu LH Zhai WX .
| Journal: Yi Chuan Xue Bao Type: ARTICLE | Literature: oryza Field: abstract Doc ID: pub12561472 | Abstract: The transformation mediated by Agrobacterium has been successfully applied to rice in recent years .
In the previous research we have transferred the Xa21 gene into five rice varieties of China , using Agrobacterium-mediated trasformation .
In this study , T-DNA flanking sequences of Xa21 transgenic rice lines were obtained by using thermal asymmetric interlaced PCR ( TAIL-PCR ) .
The flanking sequences which are actual rice DNA were identified and located on molecular linkage map developed from a ZYQ8/JX17 double haploid ( DH ) population .
A total of 22 T-DNA flanking rice sequences were isolated .
Nineteen of them displayed RFLPs between the two parents , ZYQ8 and JX17 , and were mapped on the rice chromosomes , 3 , 4 , 7 , 9 , 10 , 11 and 12 , respectively .
The genetic mapping of T-DNA integration sites in Xa21 transgenic rice will benefit the study of position effect and stable inheritance of the transgene Xa21 . | Matching Sentences: [ Sen. 7, subscore: 2.00 ]: The genetic mapping of T-DNA integration sites in Xa21 transgenic rice will benefit the study of position effect and stable inheritance of the transgene Xa21 . [ Sen. 2, subscore: 1.00 ]: In the previous research we have transferred the Xa21 gene into five rice varieties of China , using Agrobacterium-mediated trasformation . [ Sen. 3, subscore: 1.00 ]: In this study , T-DNA flanking sequences of Xa21 transgenic rice lines were obtained by using thermal asymmetric interlaced PCR ( TAIL-PCR ) .
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Score: 4.00 | Title: Cloning and characterization of receptor kinase class disease resistance gene candidates in Citrus .
| Author: Deng Z Gmitter FG .
| Journal: Theor . Appl . Genet . Type: ARTICLE | Literature: oryza Field: abstract Doc ID: pub13679986 | Abstract: The rice gene Xa21 represents a unique class of plant disease resistance ( R ) genes with distinct protein structure and broad-spectrum specificity ; few sequences or genes of this class have been cloned and characterized in other plant species .
Degenerate primers were designed from the conserved motifs in the kinase domains of Xa21 and tomato Pto , and used in PCR amplification to identify this class of resistance gene candidate ( RGC ) sequences from citrus for future evaluation of possible association with citrus canker resistance .
Twenty-nine RGC sequences highly similar to the kinase domain of Xa21 ( 55%-60% amino-acid identity ) were cloned and characterized .
To facilitate recovery of full-length gene structures and to overcome RGC mapping limitations , large-insert genomic clones ( BACs ) were identified , fingerprinted and assembled into contigs .
Southern hybridization revealed the presence of 1-3 copies of receptor-like kinase sequences ( ie , clustering ) in each BAC .
Some of these sequences were sampled by PCR amplification and direct sequencing .
Twenty-three sequences were thus obtained and classified into five groups and eight subgroups , which indicates the possibility of enhancing RGC sequence diversity from BACs .
A primer-walking strategy was employed to derive full-length gene structures from two BAC clones ; both sequences 17o6RLK and 26m19RLK contained all the features of the rice Xa21 protein , including a signal peptide , the same number of leucine-rich-repeats , and transmembrane and kinase domains .
These results demonstrate that PCR amplification with appropriately designed degenerate primers is an efficient approach for cloning receptor-like kinase class RGCs .
Utilization of BAC clones can facilitate this approach in multiple ways by improving sequence diversity , providing full-length genes , and assisting in understanding gene structures and distribution .
| Matching Sentences: [ Sen. 1, subscore: 1.00 ]: The rice gene Xa21 represents a unique class of plant disease resistance ( R ) genes with distinct protein structure and broad-spectrum specificity ; few sequences or genes of this class have been cloned and characterized in other plant species . [ Sen. 2, subscore: 1.00 ]: Degenerate primers were designed from the conserved motifs in the kinase domains of Xa21 and tomato Pto , and used in PCR amplification to identify this class of resistance gene candidate ( RGC ) sequences from citrus for future evaluation of possible association with citrus canker resistance . [ Sen. 3, subscore: 1.00 ]: Twenty-nine RGC sequences highly similar to the kinase domain of Xa21 ( 55%-60% amino-acid identity ) were cloned and characterized . [ Sen. 8, subscore: 1.00 ]: A primer-walking strategy was employed to derive full-length gene structures from two BAC clones ; both sequences 17o6RLK and 26m19RLK contained all the features of the rice Xa21 protein , including a signal peptide , the same number of leucine-rich-repeats , and transmembrane and kinase domains .
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Score: 4.00 | Title: [ Isolation and Sequence Analysis of the Xa21 Gene Wxon II Homologus from Different Species of Wild Rice in Yunnan . ] | Author: Qian J Cheng ZQ Yang MZ Liu JM Wu CJ Huang XQ .
| Journal: Yi Chuan Type: ARTICLE | Literature: oryza Field: abstract Doc ID: pub15985401 | Abstract: The Xa21 gene previously cloned from the wild rice species Oryzae longistaminata confers broad-spectrum resistance to rice leaf blight caused by different strains of Xanthomonas oryzae pv . oryzae .
Here we attempted to determine the existence of Xa21 homologs in other wild rice species and rice cultivars and the sequence differences between the homologs .
We synthesized specific primers based on the reported Xa21 sequence to amplify homologs of the gene exon II from several rice cultivars and three wild rice species in Yunnan Province , China .
The fragments cloned from various types of O rufipogon Griff from Jinghong and Yuanjiang , Yunnan Province , were highly homologous to the reported Xa21 gene exon II .
However , the fragment was not found in O officinalis Wall . and O meyeriana Baill .
Sequence analysis suggested that differences in nucleotides were located randomly in the fragments we cloned .
| Matching Sentences: [ Sen. 1, subscore: 1.00 ]: The Xa21 gene previously cloned from the wild rice species Oryzae longistaminata confers broad-spectrum resistance to rice leaf blight caused by different strains of Xanthomonas oryzae pv . oryzae . [ Sen. 2, subscore: 1.00 ]: Here we attempted to determine the existence of Xa21 homologs in other wild rice species and rice cultivars and the sequence differences between the homologs . [ Sen. 3, subscore: 1.00 ]: We synthesized specific primers based on the reported Xa21 sequence to amplify homologs of the gene exon II from several rice cultivars and three wild rice species in Yunnan Province , China . [ Sen. 4, subscore: 1.00 ]: The fragments cloned from various types of O rufipogon Griff from Jinghong and Yuanjiang , Yunnan Province , were highly homologous to the reported Xa21 gene exon II .
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Score: 4.00 | Title: [ Application of competitive PCR for screening selectable marker-free Xa21 transgenic rice ] | Author: Xia Z Gao L Luo Y Deng X Li S Zhai W | Journal: Sheng Wu Gong Cheng Xue Bao Type: In-Process | Literature: oryza Field: abstract Doc ID: pub19637639 | Abstract: Polymerase chain reaction ( PCR ) is a simple , quick and highly sensitive method .
However the accuracy of the conventional PCR assay was often affected by false positives and false negatives .
In this study , a protocol competitive PCR was used to reduce the false results in screening for selectable marker-free ( SMF ) Xa2l transgenic rice plants .
The competitive template of Xa21 was the endogenous Xa2l homologous sequence located on chromosome 11 .
The competitive template of the selectable marker gene , hygromycin phosphotransferase ( hpt ) , was an additive DNA extracted from hpt transgenic Nipponbare ( Oryza sativa L ) .
Through competitive PCR analysis of transgenic T1 plants produced by double right border binary vector , false positive or false negative samples were effectively diminished , and genuine SMF Xa21 transgenic plants were obviously obtained .
Comparing with the conventional non-competitive PCR , competitive PCR increased the accuracy for selecting SMF Xa21 transgenic plants .
The results of bacterial blight ( BB ) resistance tests and hygromycin B resistance assay of SMF Xa21 transgenic plants testified the reliability of this method .
| Matching Sentences: [ Sen. 4, subscore: 1.00 ]: The competitive template of Xa21 was the endogenous Xa2l homologous sequence located on chromosome 11 . [ Sen. 6, subscore: 1.00 ]: Through competitive PCR analysis of transgenic T1 plants produced by double right border binary vector , false positive or false negative samples were effectively diminished , and genuine SMF Xa21 transgenic plants were obviously obtained . [ Sen. 7, subscore: 1.00 ]: Comparing with the conventional non-competitive PCR , competitive PCR increased the accuracy for selecting SMF Xa21 transgenic plants . [ Sen. 8, subscore: 1.00 ]: The results of bacterial blight ( BB ) resistance tests and hygromycin B resistance assay of SMF Xa21 transgenic plants testified the reliability of this method .
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Score: 4.00 | Title: A type I-secreted , sulfated peptide triggers XA21-mediated innate immunity .
| Author: Lee SW Han SW Sririyanum M Park CJ Seo YS Ronald PC | Journal: Science Type: MEDLINE | Literature: oryza Field: abstract Doc ID: pub19892983 | Abstract: The rice Xa21 gene confers immunity to most strains of the bacterium Xanthomonas oryzae pv . oryzae ( Xoo ) .
Liquid chromatography-tandem mass spectrometry analysis of biologically active fractions from Xoo supernatants led to the identification of a 194-amino acid protein designated Ax21 ( activator of XA21-mediated immunity ) .
A sulfated , 17-amino acid synthetic peptide ( axY ( S ) 22 ) derived from the N-terminal region of Ax21 is sufficient for activity , whereas peptides lacking tyrosine sulfation are biologically inactive .
Using coimmunoprecipitation , we found that XA21 is required for axY ( S ) 22 binding and recognition . axY ( S ) 22 is 100% conserved in all analyzed Xanthomonas species , confirming that Ax21 is a pathogen-associated molecular pattern and that XA21 is a pattern recognition receptor .
| Matching Sentences: [ Sen. 4, subscore: 2.00 ]: Using coimmunoprecipitation , we found that XA21 is required for axY ( S ) 22 binding and recognition . axY ( S ) 22 is 100% conserved in all analyzed Xanthomonas species , confirming that Ax21 is a pathogen-associated molecular pattern and that XA21 is a pattern recognition receptor . [ Sen. 1, subscore: 1.00 ]: The rice Xa21 gene confers immunity to most strains of the bacterium Xanthomonas oryzae pv . oryzae ( Xoo ) . [ Sen. 2, subscore: 1.00 ]: Liquid chromatography-tandem mass spectrometry analysis of biologically active fractions from Xoo supernatants led to the identification of a 194-amino acid protein designated Ax21 ( activator of XA21-mediated immunity ) .
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Score: 4.00 | Title: Metabolomic and transcriptomic analysis of the rice response to the bacterial blight pathogen Xanthomonas oryzae pv . oryzae .
| Author: Sana TR Fischer S Wohlgemuth G Katrekar A Jung KH Ronald PC Fiehn O | Journal: Metabolomics Type: Publisher | Literature: oryza Field: abstract Doc ID: pub20676379 | Abstract: Bacterial leaf blight ( BLB ) , caused by Xanthomonas oryzae pv . oryzae ( Xoo ) , gives rise to devastating crop losses in rice .
Disease resistant rice cultivars are the most economical way to combat the disease .
The TP309 cultivar is susceptible to infection by Xoo strain PXO99 .
A transgenic variety , TP309_Xa21 , expresses the pattern recognition receptor Xa21 , and is resistant .
PXO99 big up tri , openraxST , a strain lacking the raxST gene , is able to overcome Xa21-mediated immunity .
We used a single extraction solvent to demonstrate comprehensive metabolomics and transcriptomics profiling under sample limited conditions , and analyze the molecular responses of two rice lines challenged with either PXO99 or PXO99 big up tri , openraxST .
LC-TOF raw data file filtering resulted in better within group reproducibility of replicate samples for statistical analyses .
Accurate mass match compound identification with molecular formula generation ( MFG ) ranking of 355 masses was achieved with the METLIN database .
GC-TOF analysis yielded an additional 441 compounds after BinBase database processing , of which 154 were structurally identified by retention index/MS library matching .
Multivariate statistics revealed that the susceptible and resistant genotypes possess distinct profiles .
Although few mRNA and metabolite differences were detected in PXO99 challenged TP309 compared to mock , many differential changes occurred in the Xa21-mediated response to PXO99 and PXO99 big up tri , openraxST .
Acetophenone , xanthophylls , fatty acids , alkaloids , glutathione , carbohydrate and lipid biosynthetic pathways were affected .
Significant transcriptional induction of several pathogenesis related genes in Xa21 challenged strains , as well as differential changes to GAD , PAL , ICL1 and Glutathione-S-transferase transcripts indicated limited correlation with metabolite changes under single time point global profiling conditions .
ELECTRONIC SUPPLEMENTARY MATERIAL : The online version of this article ( doi : 10 . 1007/s11306-010-0218-7 ) contains supplementary material , which is available to authorized users .
| Matching Sentences: [ Sen. 4, subscore: 1.00 ]: A transgenic variety , TP309_Xa21 , expresses the pattern recognition receptor Xa21 , and is resistant . [ Sen. 5, subscore: 1.00 ]: PXO99 big up tri , openraxST , a strain lacking the raxST gene , is able to overcome Xa21-mediated immunity . [ Sen. 11, subscore: 1.00 ]: Although few mRNA and metabolite differences were detected in PXO99 challenged TP309 compared to mock , many differential changes occurred in the Xa21-mediated response to PXO99 and PXO99 big up tri , openraxST . [ Sen. 13, subscore: 1.00 ]: Significant transcriptional induction of several pathogenesis related genes in Xa21 challenged strains , as well as differential changes to GAD , PAL , ICL1 and Glutathione-S-transferase transcripts indicated limited correlation with metabolite changes under single time point global profiling conditions .
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Score: 4.00 | Title: [ A PCR marker-based selection for resistance to bacterial blight in rice ] | Author: Lu C Li X Zhu L Zhang Q Yang W Zhao B Wang C | Journal: Yi Chuan Xue Bao Type: ARTICLE | Literature: oryza Field: abstract Doc ID: pub8695180 | Abstract: Molecular marker-based selection in plant breeding requires not only suitable molecular markers closely linked to the known genes , but a simple , economic and reliable analyzing technique .
We report here a useful PCR marker for genetic diagnostics in breeding for resistance to rice bacterial blight .
Xa21 is a newly found gene of rice which confers resistance to bacterial blight caused by Xanthomonas oryzae pv . oryzae .
We produced two F2 populations between one resistant line IRBB21 containing Xa21 and two susceptible varieties , respectively .
One PCR marker , PB78 , detected polymorphism between the susceptible varieties and the resistant line .
Cosegregation between Xa21 and PB78 was studied in the two F2 populations .
The results showed that Xa21 was closely linked to the molecular marker , the crossing over value was 2 . 48% .
Marker-based selection revealed that 100% of the plants with homozygous resistant genotype of PB78 showed resistance to bacterial blight .
The available approaches detecting molecular markers in plant breeding are also discussed . | Matching Sentences: [ Sen. 3, subscore: 1.00 ]: Xa21 is a newly found gene of rice which confers resistance to bacterial blight caused by Xanthomonas oryzae pv . oryzae . [ Sen. 4, subscore: 1.00 ]: We produced two F2 populations between one resistant line IRBB21 containing Xa21 and two susceptible varieties , respectively . [ Sen. 6, subscore: 1.00 ]: Cosegregation between Xa21 and PB78 was studied in the two F2 populations . [ Sen. 7, subscore: 1.00 ]: The results showed that Xa21 was closely linked to the molecular marker , the crossing over value was 2 . 48% .
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Score: 3.00 | Title: [ Introduction of wide spectrum rice bacterial blight resistance gene Xa21 into two-line genic male sterile rice variety Peiai 64S ] | Author: Zhao B Wang WM Zheng XW Wang CL Ma BJ Xue QZ Zhu LH Zhai WX .
| Journal: Sheng Wu Gong Cheng Xue Bao Type: ARTICLE | Literature: oryza Field: abstract Doc ID: pub10976312 | Abstract: Agrobacterium-mediated transformation of two-line genic male sterile Indica rice variety Peiai 64S was conducted using a cloned gene , Xa21 , as the foreign gene and mature embryo calli as the recipients .
A total of 46 transgenic plants had been obtained .
The PCR analysis and Southern blotting showed the integration of Xa21 gene into the genome the transgenic plants .
Results of inoculation with philippine race 6 of Xanthomonas oryzae pv . oryzae indicated that most of transgenic plants obtained high resistance to rice bacterial blight disease ( Xoo ) .
Analyses of T1 plants of the tested transgenic lines showed that integrated Xa21 gene could be steadily inherited and segregated in a 3 : 1 ratio . | Matching Sentences: [ Sen. 1, subscore: 1.00 ]: Agrobacterium-mediated transformation of two-line genic male sterile Indica rice variety Peiai 64S was conducted using a cloned gene , Xa21 , as the foreign gene and mature embryo calli as the recipients . [ Sen. 3, subscore: 1.00 ]: The PCR analysis and Southern blotting showed the integration of Xa21 gene into the genome the transgenic plants . [ Sen. 5, subscore: 1.00 ]: Analyses of T1 plants of the tested transgenic lines showed that integrated Xa21 gene could be steadily inherited and segregated in a 3 : 1 ratio .
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Score: 3.00 | Title: Are the dominant and recessive plant disease resistance genes similar?
A case study of rice R genes and Xanthomonas oryzae pv . oryzae races .
| Author: Li ZK Sanchez A Angeles E Singh S Domingo J Huang N Khush GS .
| Journal: Genetics Type: ARTICLE | Literature: oryza Field: abstract Doc ID: pub11606550 | Abstract: The resistance of rice to its bacterial blight pathogen Xanthomonas oryzae pv . oryzae ( Xoo ) has both qualitative and quantitative components that were investigated using three near-isogenic line sets for four resistance ( R ) genes ( Xa4 , xa5 , xa13 , and Xa21 ) and 12 Xoo races .
Our results indicate that these two resistance components of rice plants were associated with the properties of the R genes .
The qualitative component of the R genes was reflected by their large effects against corresponding avirulent Xoo races .
The quantitative component of the R genes was their residual effects against corresponding virulent races and their epistatic effects , which together could lead to high-level resistance in a race-specific manner .
Our results revealed important differences between the different types of R genes .
Two R genes , Xa4 and Xa21 , showed complete dominance against the avirulent Xoo races and had large residual effects against virulent ones .
They acted independently and cumulatively , suggesting they are involved in different pathways of the rice defensive system .
The third R gene , xa5 , showed partial dominance or additivity to the avirulent Xoo races and had relatively small but significant residual effects against the virulent races .
In contrast , xa13 was completely recessive , had no residual effects against the virulent races , and showed more pronounced race specificity .
There was a strong interaction leading to increased resistance between xa13 and xa5 and between either of them and Xa4 or Xa21 , suggesting their regulatory roles in the rice defensive pathway ( s ) .
Our results indicated that high-level and durable resistance to Xoo should be more efficiently achieved by pyramiding different types of R genes . | Matching Sentences: [ Sen. 1, subscore: 1.00 ]: The resistance of rice to its bacterial blight pathogen Xanthomonas oryzae pv . oryzae ( Xoo ) has both qualitative and quantitative components that were investigated using three near-isogenic line sets for four resistance ( R ) genes ( Xa4 , xa5 , xa13 , and Xa21 ) and 12 Xoo races . [ Sen. 6, subscore: 1.00 ]: Two R genes , Xa4 and Xa21 , showed complete dominance against the avirulent Xoo races and had large residual effects against virulent ones . [ Sen. 10, subscore: 1.00 ]: There was a strong interaction leading to increased resistance between xa13 and xa5 and between either of them and Xa4 or Xa21 , suggesting their regulatory roles in the rice defensive pathway ( s ) .
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Score: 3.00 | Title: [ A genetically modified japonica restorer line , C418-Xa21 , and its hybrid rice with bacterial blight resistance ] | Author: Li XB Yi CD Zhai WX Yang ZY Zhu LH .
| Journal: Sheng Wu Gong Cheng Xue Bao Type: ARTICLE | Literature: oryza Field: abstract Doc ID: pub11702691 | Abstract: The cloned bacterial blight ( BB ) resistance gene Xa21 was transferred into C418 , a major restorer line of japonica hybrid rice in China , using an Agrobacterium-mediated system .
The integrated single copy of transgene displayed a 3 : 1 segregation ratio in T1 generation in PCR and resistance analyses .
The transgenic homozygous C418-Xa21 lines were selected in T2 generation through PCR and resistance analyses .
The selected transgenic restorer lines were then crossed with a commonly used sterile line , TijinA , to produce Xa21 transgenic hybrid rice .
Molecular analysis revealed that the produced hybrid rice , named as Tiyou418-Xa21 , inherited the transgene .
Both C418-Xa21 and Tiyou418-Xa21 plants displayed high resistance with a broad spectrum to Xoo races and maintained their normal elite agronomic characters .
We also observed that the resistance level of Tiyou418-Xa21 was obviously higher than that of C418-Xa21 which may be attributed to their differences in genetic background .
The propagation of this BB resistant hybrid variety with the transgene Xa21 with extend hybrid rice production in north China . | Matching Sentences: [ Sen. 1, subscore: 1.00 ]: The cloned bacterial blight ( BB ) resistance gene Xa21 was transferred into C418 , a major restorer line of japonica hybrid rice in China , using an Agrobacterium-mediated system . [ Sen. 4, subscore: 1.00 ]: The selected transgenic restorer lines were then crossed with a commonly used sterile line , TijinA , to produce Xa21 transgenic hybrid rice . [ Sen. 8, subscore: 1.00 ]: The propagation of this BB resistant hybrid variety with the transgene Xa21 with extend hybrid rice production in north China .
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Score: 3.00 | Title: The Xanthomonas oryzae pv . lozengeoryzae raxP and raxQ genes encode an ATP sulphurylase and adenosine-5-phosphosulphate kinase that are required for AvrXa21 avirulence activity .
| Author: Shen Y Sharma P da Silva FG Ronald P | Journal: Mol . Microbiol . Type: ARTICLE | Literature: oryza Field: abstract Doc ID: pub11967067 | Abstract: Xanthomonas oryzae pv . oryzae ( Xoo ) Philippine race 6 ( PR6 ) is unable to cause bacterial blight disease on rice lines containing the rice resistance gene Xa21 but is virulent on non-Xa21 rice lines , indicating that PR6 carries avirulence ( avrXa21 ) determinants required for recognition by XA21 .
Here we show that two Xoo genes , raxP and raxQ , are required for AvrXa21 activity . raxP and raxQ , which reside in a genomic cluster of sulphur assimilation genes , encode an ATP sulphurylase and APS ( adenosine-5-phosphosulphate ) kinase .
These enzymes function together to produce activated forms of sulphate , APS and PAPS ( 3-phosphoadenosine-5-phosphosulphate ) .
Xoo PR6 strains carrying disruptions in either gene , PR6DeltaraxP or PR6DeltaraxQ , are unable to produce APS and PAPS and are virulent on Xa21-containing rice lines .
RaxP and RaxQ are similar to the bacterial symbiont Sinorhizobium meliloti host specificity proteins , NodP and NodQ and the Escherichia coli cysteine synthesis proteins CysD , CysN and CysC .
The APS and PAPS produced by RaxP and RaxQ are used for both cysteine synthesis and sulphation of other molecules .
Mutation in Xoo xcysI , a homologue of Escherichia coli cysI that is required for cysteine synthesis , blocked APS or PAPS-dependent cysteine synthesis but did not affect AvrXa21 activity , suggesting that AvrXa21 activity is related to sulphation rather than cysteine synthesis .
Taken together , these results demonstrate that APS and PAPS production plays a critical role in determining avirulence of a phytopathogen and reveal a commonality between symbiotic and phytopathogenic bacteria .
| Matching Sentences: [ Sen. 1, subscore: 2.00 ]: Xanthomonas oryzae pv . oryzae ( Xoo ) Philippine race 6 ( PR6 ) is unable to cause bacterial blight disease on rice lines containing the rice resistance gene Xa21 but is virulent on non-Xa21 rice lines , indicating that PR6 carries avirulence ( avrXa21 ) determinants required for recognition by XA21 . [ Sen. 4, subscore: 1.00 ]: Xoo PR6 strains carrying disruptions in either gene , PR6DeltaraxP or PR6DeltaraxQ , are unable to produce APS and PAPS and are virulent on Xa21-containing rice lines .
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Score: 3.00 | Title: Bacterial genes involved in type I secretion and sulfation are required to elicit the rice Xa21-mediated innate immune response .
| Author: da Silva FG Shen Y Dardick C Burdman S Yadav RC de Leon AL Ronald PC .
| Journal: Mol .
Plant Microbe Interact .
Type: ARTICLE | Literature: oryza Field: abstract Doc ID: pub15195942 | Abstract: Innate immunity to microorganisms relies on the specific sensing of pathogen-associated molecules by host recognition receptors .
Whereas studies in animals have largely focused on the recognition of extracellular pathogen-associated molecules by the TLR ( toll-like receptor ) superfamily , few studies have been carried out in plants , and it is not understood how these molecules are secreted or modified .
The rice Xa21 gene encodes a receptor-like kinase that provides immunity against strains of the bacterial pathogen Xanthomonas oryzae pv . oryzae carrying AvrXa21 activity .
We identified four X oryzae pv . oryzae genes that are required for AvrXa21 activity . raxA , raxB , and raxC encode proteins with similarity to a membrane fusion protein , an ATP-binding cassette transporter , and an outer membrane protein , respectively , of bacterial type I secretion systems .
The fourth gene , raxST , encodes a sulfotransferase-like protein .
Sequence analysis of three naturally occurring X oryzae pv . oryzae strains no longer recognized by Xa21 revealed alterations in the raxST and raxA genes .
The raxC gene complemented an Escherichia coli tolC mutant for secretion of a double glycine-leader peptide confirming the function of raxC in type I secretion .
These results indicate that bacterial type I secretion is necessary for Xa21-mediated recognition and immunity and further suggest that type I secretion and modification of pathogen-associated molecules play an important role in triggering the innate immune response in rice . | Matching Sentences: [ Sen. 3, subscore: 1.00 ]: The rice Xa21 gene encodes a receptor-like kinase that provides immunity against strains of the bacterial pathogen Xanthomonas oryzae pv . oryzae carrying AvrXa21 activity . [ Sen. 6, subscore: 1.00 ]: Sequence analysis of three naturally occurring X oryzae pv . oryzae strains no longer recognized by Xa21 revealed alterations in the raxST and raxA genes . [ Sen. 8, subscore: 1.00 ]: These results indicate that bacterial type I secretion is necessary for Xa21-mediated recognition and immunity and further suggest that type I secretion and modification of pathogen-associated molecules play an important role in triggering the innate immune response in rice .
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Score: 3.00 | Title: RaxH/RaxR : a two-component regulatory system in Xanthomonas oryzae pv . oryzae required for AvrXa21 activity .
| Author: Burdman S Shen Y Lee SW Xue Q Ronald P | Journal: Mol .
Plant Microbe Interact .
Type: ARTICLE | Literature: oryza Field: abstract Doc ID: pub15195943 | Abstract: Xanthomonas oryzae pv . oryzae is the causal agent of bacterial leaf blight , one of the most serious diseases in rice .
X oryzae pv . oryzae Philippine race 6 ( PR6 ) strains are unable to establish infection in rice lines expressing the resistance gene Xa21 .
Although the pathogen-associated molecule that triggers the Xa21-mediated defense response ( AvrXa21 ) is unknown , six rax ( required for AvrXa21 activity ) genes encoding proteins involved in sulfur metabolism and Type I secretion were recently identified .
Here , we report on the identification of two additional rax genes , raxR and raxH , which encode a response regulator and a histidine protein kinase of two-component regulatory systems , respectively .
Null mutants of PR6 strain PXO99 that are impaired in either raxR , raxH , or both cause lesions significantly longer and grow to significantly higher levels than does the wild-type strain in Xa21-rice leaves .
Both raxR and raxH mutants are complemented to wild-type levels of AvrXa21 activity by introduction of expression vectors carrying raxR and raxH , respectively .
These null mutants do not affect AvrXa7 and AvrXa10 activities , as observed in inoculation experiments with Xa7 and Xa10-rice lines .
Western blot and raxR/gfp promoter-reporter analyses confirmed RaxR expression in X oryzae pv . oryzae .
The results of promoter-reporter studies also suggest that the previously identified raxSTAB operon is a target for RaxH/RaxR regulation .
Characterization of the RaxH/RaxR system provides new opportunities for understanding the specificity of the X oryzae pv . oryzae-Xa21 interaction and may contribute to the identification of AvrXa21 . | Matching Sentences: [ Sen. 2, subscore: 1.00 ]: X oryzae pv . oryzae Philippine race 6 ( PR6 ) strains are unable to establish infection in rice lines expressing the resistance gene Xa21 . [ Sen. 3, subscore: 1.00 ]: Although the pathogen-associated molecule that triggers the Xa21-mediated defense response ( AvrXa21 ) is unknown , six rax ( required for AvrXa21 activity ) genes encoding proteins involved in sulfur metabolism and Type I secretion were recently identified . [ Sen. 5, subscore: 1.00 ]: Null mutants of PR6 strain PXO99 that are impaired in either raxR , raxH , or both cause lesions significantly longer and grow to significantly higher levels than does the wild-type strain in Xa21-rice leaves .
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Score: 3.00 | Title: [ Analysis of the transgenic rice plants derived from transformed anther calli ] | Author: Jiang S Chen CY Cheng ZK Cai R Zhai WX Zhu LH .
| Journal: Yi Chuan Xue Bao Type: ARTICLE | Literature: oryza Field: abstract Doc ID: pub15633644 | Abstract: Rice calli derived from anther culture were used as recipient to transfer a rice blight resistance gene , Xa21 , into a japonica rice variety , Taipei 309 , via Agrobacterium-mediated transformation .
Seven green transgenic plants , including one mixoploid , two haploid , and four diploid plants , were regenerated .
PCR , Southern blot , FISH and blight resistance analysis all indicated that Xa21 gene has been integrated into the T0 plant genomes .
T1 generations of the four diploid T0 plants were further investigated for resistance segregation .
Chi2 test showed that two T1 populations segregated with a ratio of 3 : 1 , indicating that a single copy of Xa21 gene was integrated into the genome , whereas the segregation ratios of the other two T1 populations were non-Mendelian .
Therefore , the four diploid transgenic plants should be heterozygous diploids . | Matching Sentences: [ Sen. 1, subscore: 1.00 ]: Rice calli derived from anther culture were used as recipient to transfer a rice blight resistance gene , Xa21 , into a japonica rice variety , Taipei 309 , via Agrobacterium-mediated transformation . [ Sen. 3, subscore: 1.00 ]: PCR , Southern blot , FISH and blight resistance analysis all indicated that Xa21 gene has been integrated into the T0 plant genomes . [ Sen. 5, subscore: 1.00 ]: Chi2 test showed that two T1 populations segregated with a ratio of 3 : 1 , indicating that a single copy of Xa21 gene was integrated into the genome , whereas the segregation ratios of the other two T1 populations were non-Mendelian .
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Score: 3.00 | Title: Rice NRR , a negative regulator of disease resistance , interacts with Arabidopsis NPR1 and rice NH1 .
| Author: Chern M Canlas PE Fitzgerald HA Ronald PC .
| Journal: Plant J Type: ARTICLE | Literature: oryza Field: abstract Doc ID: pub16115061 | Abstract: Arabidopsis NPR1/NIM1 is a key regulator of systemic acquired resistance ( SAR ) , which confers lasting broad-spectrum resistance .
Over-expression of Arabidopsis NPR1 or the NPR1 homolog 1 ( NH1 ) in rice results in enhanced resistance to the pathogen Xanthomonasoryzae pv . oryzae ( Xoo ) , suggesting the presence of a related defense pathway in rice .
We investigated this pathway in rice by identifying proteins that interact with NH1 .
Here we report the isolation and characterization of a rice cDNA encoding a novel protein , named NRR ( for negative regulator of resistance ) .
NRR interacts with NPR1 in the NPR1-interacting domain ( NI25 ) consisting of 25 amino acids .
NRR also interacts with NH1 ; however , NI25 was not sufficient for a strong interaction , indicating a difference between the rice and the Arabidopsis proteins .
Silencing of NRR in rice had little effect on resistance to Xoo .
When constitutively over-expressed in rice , NRR affected basal resistance , age-related resistance and Xa21-mediated resistance , causing enhanced susceptibility to Xoo .
This phenotype was correlated with elevated NRR mRNA and protein levels and increased Xoo growth .
Over-expression of NRR suppressed the induction of defense-related genes .
NRR : GFP ( green fluorescent protein ) protein was localized to the nucleus , indicating that NRR may act directly to suppress the activation of defense genes .
The fact that NRR compromises Xa21-mediated resistance indicates cross-talk or overlap between NH1 and Xa21-mediated pathways . | Matching Sentences: [ Sen. 12, subscore: 2.00 ]: The fact that NRR compromises Xa21-mediated resistance indicates cross-talk or overlap between NH1 and Xa21-mediated pathways . [ Sen. 8, subscore: 1.00 ]: When constitutively over-expressed in rice , NRR affected basal resistance , age-related resistance and Xa21-mediated resistance , causing enhanced susceptibility to Xoo .
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Score: 3.00 | Title: Perception of the chitin oligosaccharides contributes to disease resistance to blast fungus Magnaporthe oryzae in rice .
| Author: Kishimoto K Kouzai Y Kaku H Shibuya N Minami E Nishizawa Y | Journal: Plant J Type: MEDLINE | Literature: oryza Field: abstract Doc ID: pub21070413 | Abstract: Chitin is a component of fungal cell walls , and its fragments act as elicitors in many plants .
The plasma membrane glycoprotein CEBiP , which possesses LysM domains , is a receptor for the chitin elicitor ( CE ) in rice .
Here , we report that the perception of CE by CEBiP contributes to disease resistance against the rice blast fungus , Magnaporthe oryzae , and that enhanced responses to CE by engineering CEBiP increase disease tolerance .
Knockdown of CEBiP expression allowed increased spread of the infection hyphae .
To enhance defense responses to CE , we constructed chimeric genes composed of CEBiP and Xa21 , which mediate resistance to rice bacterial leaf blight .
The expression of either CRXa1 or CRXa3 , each of which contains the whole extracellular portion of CEBiP , the whole intracellular domain of XA21 , and the transmembrane domain from either CEBiP or XA21 , induced cell death accompanied by an increased production of reactive oxygen and nitrogen species after treatment with CE .
Rice plants expressing the chimeric receptor exhibited necrotic lesions in response to CE and became more resistant to M oryzae .
Deletion of the first LysM domain in CRXA1 abolished these cellular responses .
These results suggest that CEs are produced and recognized through the LysM domain of CEBiP during the interaction between rice and M oryzae and imply that engineering pattern recognition receptors represents a new strategy for crop protection against fungal diseases .
| Matching Sentences: [ Sen. 6, subscore: 2.00 ]: The expression of either CRXa1 or CRXa3 , each of which contains the whole extracellular portion of CEBiP , the whole intracellular domain of XA21 , and the transmembrane domain from either CEBiP or XA21 , induced cell death accompanied by an increased production of reactive oxygen and nitrogen species after treatment with CE . [ Sen. 5, subscore: 1.00 ]: To enhance defense responses to CE , we constructed chimeric genes composed of CEBiP and Xa21 , which mediate resistance to rice bacterial leaf blight .
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Score: 3.00 | Title: Enhancement of MAMP signaling by chimeric receptors improves disease resistance in plants .
| Author: Kishimoto K Kouzai Y Kaku H Shibuya N Minami E Nishizawa Y | Journal: Plant Signal Behav Type: MEDLINE | Literature: oryza Field: abstract Doc ID: pub21364321 | Abstract: Plants activate defense responses through the recognition of microbe-associated molecular patterns ( MAMPs ) .
Recently , several pattern-recognition receptors ( PRRs ) have been identified in plants , paving the way for manipulating MAMP signaling .
CEBiP is a receptor for the chitin elicitor ( CE ) identified in the rice plasma membrane and XA21 is a member of the receptor-like protein kinase ( RLK ) family that confers disease resistance to rice bacterial leaf blight expressing the sulfated protein Ax21 .
To improve resistance to rice blast , the most serious fungal disease of rice , we aimed to create a defense system that combines high affinity of CEBiP for CE and the ability of XA21 to confer disease resistance .
Cultured rice cells expressing the chimeric receptor CRXA , which consists of CEBiP and the intracellular region of XA21 , induced cell death accompanied by an increased production of reactive oxygen and nitrogen species after exposure to CE .
Rice plants expressing the chimeric receptor exhibited more resistance to rice blast Engineering PRRs may be a new strategy in molecular breeding for achieving disease resistance .
| Matching Sentences: [ Sen. 3, subscore: 1.00 ]: CEBiP is a receptor for the chitin elicitor ( CE ) identified in the rice plasma membrane and XA21 is a member of the receptor-like protein kinase ( RLK ) family that confers disease resistance to rice bacterial leaf blight expressing the sulfated protein Ax21 . [ Sen. 4, subscore: 1.00 ]: To improve resistance to rice blast , the most serious fungal disease of rice , we aimed to create a defense system that combines high affinity of CEBiP for CE and the ability of XA21 to confer disease resistance . [ Sen. 5, subscore: 1.00 ]: Cultured rice cells expressing the chimeric receptor CRXA , which consists of CEBiP and the intracellular region of XA21 , induced cell death accompanied by an increased production of reactive oxygen and nitrogen species after exposure to CE .
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Score: 3.00 | Title: Identification and expression analysis of components involved in rice Xa21-mediated disease resistance signalling .
| Author: Bai H Lan JP Gan Q Wang XY Hou MM Cao YH Li LY Liu LJ Hao YJ Yin CC Wu L Zhu LH Liu GZ | Journal: Plant Biol ( Stuttg ) Type: Publisher | Literature: oryza Field: abstract Doc ID: pub22672582 | Abstract: Rice Xa21 gene encodes a receptor-like kinase that confers broad-spectrum resistance against Xanthomonas oryzae pv . oryzae ( Xoo ) .
Recently , a number of genes involved in the Xa21-mediated disease resistance pathway have been identified .
Based on our previous data and the literature , we chose 16 candidate proteins and made corresponding antibodies .
Using Western blotting , we systematically investigated the expression profile of the proteins in Xa21-mediated disease resistance response .
We found nine proteins with altered expression .
We further compared their expression in resistance , susceptible and mock responses , and found that GST expression was up-regulated during the resistance process , indicating GST is a positive regulator in resistance responses .
ATPsB expression was down-regulated during both the resistance and susceptible response processes , although it was higher in the resistance response than that in the susceptible response .
The total amount of MYB , GAPDH , CatB , Trx and NB-ARC proteins was lower in the resistance than in the susceptible response , but their abundance per unit bacteria in the resistance response was still higher than in the susceptible response , suggesting that these proteins might be positive regulators in the resistance response .
In addition , expression of another ERF was induced by inoculation with bacterial blight pathogen , and expression of Zf-LSD1 was activated by wounding stress alone .
Interestingly , most proteins showed similar altered expression patterns in the resistance and susceptible responses , but differed to some extents , implying that both responses might share common molecular mechanisms .
This study revealed evidence of resistance-related protein expression , providing a foundation for better understanding of their functions .
| Matching Sentences: [ Sen. 1, subscore: 1.00 ]: Rice Xa21 gene encodes a receptor-like kinase that confers broad-spectrum resistance against Xanthomonas oryzae pv . oryzae ( Xoo ) . [ Sen. 2, subscore: 1.00 ]: Recently , a number of genes involved in the Xa21-mediated disease resistance pathway have been identified . [ Sen. 4, subscore: 1.00 ]: Using Western blotting , we systematically investigated the expression profile of the proteins in Xa21-mediated disease resistance response .
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Score: 3.00 | Title: A receptor kinase-like protein encoded by the rice disease resistance gene , Xa21 .
| Author: Song WY Wang GL Chen LL Kim HS Pi LY Holsten T Gardner J Wang B Zhai WX Zhu LH Fauquet C Ronald P | Journal: Science Type: ARTICLE | Literature: oryza Field: abstract Doc ID: pub8525370 | Abstract: The rice Xa21 gene , which confers resistance to Xanthomonas oryzae pv . oryzae race 6 , was isolated by positional cloning .
Fifty transgenic rice plants carrying the cloned Xa21 gene display high levels of resistance to the pathogen .
The sequence of the predicted protein , which carries both a leucine-rich repeat motif and a serine-threonine kinase-like domain , suggests a role in cell surface recognition of a pathogen ligand and subsequent activation of an intracellular defense response .
Characterization of Xa21 should facilitate understanding of plant disease resistance and lead to engineered resistance in rice . | Matching Sentences: [ Sen. 1, subscore: 1.00 ]: The rice Xa21 gene , which confers resistance to Xanthomonas oryzae pv . oryzae race 6 , was isolated by positional cloning . [ Sen. 2, subscore: 1.00 ]: Fifty transgenic rice plants carrying the cloned Xa21 gene display high levels of resistance to the pathogen . [ Sen. 4, subscore: 1.00 ]: Characterization of Xa21 should facilitate understanding of plant disease resistance and lead to engineered resistance in rice .
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Score: 3.00 | Title: The molecular basis of disease resistance in rice .
| Author: Ronald PC .
| Journal: Plant Mol . Biol . Type: ARTICLE | Literature: oryza Field: abstract Doc ID: pub9291971 | Abstract: The rice gene Xa21 conferring resistance to Xanthomonas oryzae pv . oryzae ( Xoo ) , was isolated using a map-based cloning strategy .
Compared with previously cloned genes , the structure of Xa21 represents a novel class of plant disease R genes encoding a putative receptor kinase ( RK ) .
This article proposes a model for the mode of action of Xa21 and summarizes our current knowledge of the modular basis of resistance in rice to bacterial leaf blight and blast | Matching Sentences: [ Sen. 1, subscore: 1.00 ]: The rice gene Xa21 conferring resistance to Xanthomonas oryzae pv . oryzae ( Xoo ) , was isolated using a map-based cloning strategy . [ Sen. 2, subscore: 1.00 ]: Compared with previously cloned genes , the structure of Xa21 represents a novel class of plant disease R genes encoding a putative receptor kinase ( RK ) . [ Sen. 3, subscore: 1.00 ]: This article proposes a model for the mode of action of Xa21 and summarizes our current knowledge of the modular basis of resistance in rice to bacterial leaf blight and blast
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Score: 2.00 | Title: [ Amplification and analysis of T-DNA flanking sequences in transgenic rice ] | Author: Fang J Zhai WX Wang WM Li SW Zhu LH .
| Journal: Yi Chuan Xue Bao Type: ARTICLE | Literature: oryza Field: abstract Doc ID: pub11329876 | Abstract: Rice transformation mediated by Agrobacterium tumefaciens has technically matured to some extent , but the mechanics of T-DNA integration in transgenic rice remains largely unknown .
Using thermal asymmetric interlaced PCR ( TAIL-PCR ) , we analyzed the flanking sequences of T-DNAs in transgenic rice plants , in which the resistance gene for rice bacterial blight disease , Xa21 , had been integrated stably .
Sequence analysis of 24 fragments amplified by TAIL-PCR showed that of them 14 were rice genomic DNA , 9 contained vector backbone sequences , and one was a fragment of the exogenous gene Xa21 .
The characteristics of the 14 rice genomic DNA sequences at T-DNA integrated sites are significantly different from those of the reported rice genomic sequences into which exogenous genes were integrated through direct DNA transformation methods .
T-DNA border sequences integrated in rice genome have similar features as those integrated in dicotyledonous genomes .
In the backbone containing flanking sequences ( 37 . 5% , 9/24 ) vector backbones appeared in different types . | Matching Sentences: [ Sen. 2, subscore: 1.00 ]: Using thermal asymmetric interlaced PCR ( TAIL-PCR ) , we analyzed the flanking sequences of T-DNAs in transgenic rice plants , in which the resistance gene for rice bacterial blight disease , Xa21 , had been integrated stably . [ Sen. 3, subscore: 1.00 ]: Sequence analysis of 24 fragments amplified by TAIL-PCR showed that of them 14 were rice genomic DNA , 9 contained vector backbone sequences , and one was a fragment of the exogenous gene Xa21 .
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Score: 2.00 | Title: Marker assisted selection of bacterial blight resistance genes in rice .
| Author: Davierwala AP Reddy AP Lagu MD Ranjekar PK Gupta VS .
| Journal: Biochem . Genet . Type: ARTICLE | Literature: oryza Field: abstract Doc ID: pub11590832 | Abstract: Bacterial leaf blight caused by Xanthomonas oryzae pv . oryzae is one of the most important diseases affecting rice production in Asia .
We were interested in surveying rice genotypes that are popularly used in the Indian breeding program for conferring resistance to bacterial blight , using 11 STMS and 6 STS markers .
The basis of selection of these DNA markers was their close linkage to xa5 , xa13 , and Xa21 genes and their positions on the rice genetic map relative to bacterial blight resistance genes .
Eight lines were found to contain the xa5 gene while two lines contained Xa21 gene and none of the lines contained the xa13 gene with the exception of its near-isogenic line .
Using the polymorphic markers obtained in the initial survey , marker-assisted selection was performed in the F3 population of a cross between IR-64 and IET-14444 to detect lines containing multiple resistance genes .
Of the 59 progeny lines analyzed , eight lines contained both the resistance genes , xa5 and Xa4 . | Matching Sentences: [ Sen. 3, subscore: 1.00 ]: The basis of selection of these DNA markers was their close linkage to xa5 , xa13 , and Xa21 genes and their positions on the rice genetic map relative to bacterial blight resistance genes . [ Sen. 4, subscore: 1.00 ]: Eight lines were found to contain the xa5 gene while two lines contained Xa21 gene and none of the lines contained the xa13 gene with the exception of its near-isogenic line .
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Score: 2.00 | Title: [ Study on the teratogenicity effects of genetically modified rice with Xa21 on rats ] | Author: Li Y Piao J Zhuo Q Chen X Mao D Yang L Yang X | Journal: Type: ARTICLE | Literature: oryza Field: abstract Doc ID: pub15727184 | Abstract: OBJECTIVE : To observe the effects of genetically modified rice with Xa21 on the development of rat embryos .
METHODS : According to sex , weanling rats were divided into four groups : transgenic rice group , non-transgenic rice group , AIN93G negative control group and MATDA positive control group .
The rats were fed with corresponding food for 90 days and mated .
The development of maternal rats and embryos were observed .
RESULTS : The body weight gain of pregnant rats and the body weight , body length and tail length of fetal rats in transgenic rice group were significant increased than those in positive control group .
The number of death embryos and adsorption embryos , the malformation rate ( appearance , viscera , skeleton ) in transgenic rice group were lower than those in positive control group .
There were no significant difference of all indicators among transgenic rice group , non-transgenic rice group and AIN93G negative control group .
CONCLUSION : Compared with the non-transgenic rice , transgenic rice modified with Xa21 gene showed no significant differences in rat pregnant rate and embryo development . | Matching Sentences: [ Sen. 1, subscore: 1.00 ]: OBJECTIVE : To observe the effects of genetically modified rice with Xa21 on the development of rat embryos . [ Sen. 8, subscore: 1.00 ]: CONCLUSION : Compared with the non-transgenic rice , transgenic rice modified with Xa21 gene showed no significant differences in rat pregnant rate and embryo development .
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Score: 2.00 | Title: [ Effects of transgenes insertion on pollen vigor and hybrid seed set of rice ] | Author: Wei X Yuan X Yu H Wang Y Tang S Liao X | Journal: Type: ARTICLE | Literature: oryza Field: abstract Doc ID: pub15852969 | Abstract: In this paper , the effects of transgenes insertion on the outcross potentiality of rice varieties were assessed by pollen vigor and hybrid seed set .
The in vitro pollen germination rates of five transgenic rice lines transformed respectively with bar , crylAb , BADH and Xa21 gene were investigated , and compared with their relative receptor rice varieties .
The results showed that there existed a significant difference in in vitro pollen germination rates between receptor rice varieties , but no significant difference was found between transgenic rice varieties and their relative receptors .
The in vitro pollen germination rate for transgenic rice varieties varied from 0 . 416 to 0 . 584 , similar to that of their relative receptors ( 0 . 400-0 . 574 ) .
Investigation on the hybrid seed set of 26 hand-crosses showed that the inserted bar or crylAb gene had a significant effect on the hybrid seed set of receptors , while the effect of Xa21 gene was smaller .
The hybrid seed set rate of non-transgenic rice in crosses with transgenic rice ( pollen donor ) was from 0 . 056 to 0 . 413 , not different from that in crosses with their relative receptors ( 0 . 052-0 . 417 ) .
Its suggested that transgenes insertion had little effect on the outcross potentiality of rice varieties . | Matching Sentences: [ Sen. 2, subscore: 1.00 ]: The in vitro pollen germination rates of five transgenic rice lines transformed respectively with bar , crylAb , BADH and Xa21 gene were investigated , and compared with their relative receptor rice varieties . [ Sen. 5, subscore: 1.00 ]: Investigation on the hybrid seed set of 26 hand-crosses showed that the inserted bar or crylAb gene had a significant effect on the hybrid seed set of receptors , while the effect of Xa21 gene was smaller .
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Score: 2.00 | Title: From the Academy : Colloquium review .
Unique characteristics of Xanthomonas oryzae pv . oryzae AvrXa21 and implications for plant innate immunity .
| Author: Lee SW Han SW Bartley LE Ronald PC .
| Journal: Proc . Natl . Acad . Sci . USA Type: ARTICLE | Literature: oryza Field: abstract Doc ID: pub17082309 | Abstract: This article provides a brief overview of some of the major concepts and molecular features of plant and animal innate immune systems .
The rice pathogen recognition receptor , XA21 , confers resistance to Xanthomonas oryzae pv . oryzae strains producing the AvrXa21 elicitor .
Xa21 codes for a receptor-like kinase consisting of an extracellular leucine-rich repeat domain , a transmembrane domain , and a cytoplasmic kinase domain .
We show that AvrXa21 activity requires the presence of rax ( required for AvrXa21 ) A , raxB , and raxC genes that encode components of a type one secretion system .
In contrast , an hrpC ( - ) strain deficient in type three secretion maintains AvrXa21 activity .
Xanthomonas campestris pv . campestris can express AvrXa21 activity if raxST , encoding a putative sulfotransferase , and raxA are provided in trans .
Expression of rax genes depends on population density and other functioning rax genes .
This and other data suggest that the AvrXa21 pathogen-associated molecule is involved in quorum sensing .
Together these data suggest that AvrXa21 represents a previously uncharacterized class of Gram-negative bacterial signaling molecules .
These results from our studies of the XA21/AvrXa21 interaction call for some modifications in the way we think about innate immunity strategies .
| Matching Sentences: [ Sen. 2, subscore: 1.00 ]: The rice pathogen recognition receptor , XA21 , confers resistance to Xanthomonas oryzae pv . oryzae strains producing the AvrXa21 elicitor . [ Sen. 3, subscore: 1.00 ]: Xa21 codes for a receptor-like kinase consisting of an extracellular leucine-rich repeat domain , a transmembrane domain , and a cytoplasmic kinase domain .
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Score: 2.00 | Title: Adapting rice anther culture to gene transformation and RNA interference .
| Author: Chen C Xiao H Zhang W Wang A Xia Z Li X Zhai W Cheng Z Zhu L | Journal: Sci .
China , C , Life Sci .
Type: ARTICLE | Literature: oryza Field: abstract Doc ID: pub17172048 | Abstract: Anther culture offers a rapid method of generating homozygous lines for breeding program and genetic analysis .
To produce homozygous transgenic lines of rice ( Oryza sativa L ) in one step , we developed an efficient protocol of anther-callus-based transformation mediated by Agrobacterium after optimizing several factors influencing efficient transformation , including callus induction and Agrobacterium density for co-cultivation .
Using this protocol , we obtained 145 independent green transformants from five cultivars of japonica rice by transformation with a binary vector pCXK1301 bearing the rice gene , Xa21 for resistance to bacterial blight , of which 140 were further confirmed by PCR and Southern hybridization analysis , including haploids ( 32 . 1% ) , diploids ( 62 . 1% ) and mixoploids ( 7 . 5% ) .
Fifteen diploids were found to be doubled haploids , which accounted for 10 . 7% of the total positive lines .
Finally , by including 28 from colchicine induced or spontaneous diploidization of haploids later after transformation , a total of 43 doubled haploids ( 30 . 7% ) of Xa21 transgenic lines were obtained .
We also generated two RNAi transgenic haploids of the rice OsMADS2 gene , a putative redundant gene of OsMADS4 based on their sequence similarity , to investigate its possible roles in rice flower development by this method .
Flowers from the two OsMADS2 RNAi transgenic haploids displayed obvious homeotic alternations , in which lodicules were transformed into palea/lemma-like it issues , whereas identities of other floral organs were maintained .
The phenotypic alternations were proved to result from specific transcriptional suppression of OsMADS2 gene by the introduced RNAi transgene .
The results confirmed that OsMADS2 is involved in lodicule development of rice flower and functionally redundant with OsMADS4 gene .
Our results demonstrated that rice anther culture could be adapted to gene transformation and RNAi analysis in rice . | Matching Sentences: [ Sen. 3, subscore: 1.00 ]: Using this protocol , we obtained 145 independent green transformants from five cultivars of japonica rice by transformation with a binary vector pCXK1301 bearing the rice gene , Xa21 for resistance to bacterial blight , of which 140 were further confirmed by PCR and Southern hybridization analysis , including haploids ( 32 . 1% ) , diploids ( 62 . 1% ) and mixoploids ( 7 . 5% ) . [ Sen. 5, subscore: 1.00 ]: Finally , by including 28 from colchicine induced or spontaneous diploidization of haploids later after transformation , a total of 43 doubled haploids ( 30 . 7% ) of Xa21 transgenic lines were obtained .
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Score: 2.00 | Title: Pyramiding transgenic resistance in elite indica rice cultivars against the sheath blight and bacterial blight .
| Author: Maruthasalam S Kalpana K Kumar KK Loganathan M Poovannan K Raja JA Kokiladevi E Samiyappan R Sudhakar D Balasubramanian P | Journal: Type: ARTICLE | Literature: oryza Field: abstract Doc ID: pub17221225 | Abstract: Elite indica rice cultivars were cotransformed with genes expressing a rice chitinase ( chi11 ) and a thaumatin-like protein ( tlp ) conferring resistance to fungal pathogens and a serine-threonine kinase ( Xa21 ) conferring bacterial blight resistance , through particle bombardment , with a view to pyramiding sheath blight and bacterial blight resistance .
Molecular analyses of putative transgenic lines by polymerase chain reaction , Southern Blot hybridization , and Western Blotting revealed stable integration and expression of the transgenes in a few independent transgenic lines .
Progeny analyses showed the stable inheritance of transgenes to their progeny .
Coexpression of chitinase and thaumatin-like protein in the progenies of a transgenic Pusa Basmati1 line revealed an enhanced resistance to the sheath blight pathogen , Rhizoctonia solani , as compared to that in the lines expressing the individual genes .
A transgenic Pusa Basmati1 line pyramided with chi11 , tlp , and Xa21 showed an enhanced resistance to both sheath blight and bacterial blight .
| Matching Sentences: [ Sen. 1, subscore: 1.00 ]: Elite indica rice cultivars were cotransformed with genes expressing a rice chitinase ( chi11 ) and a thaumatin-like protein ( tlp ) conferring resistance to fungal pathogens and a serine-threonine kinase ( Xa21 ) conferring bacterial blight resistance , through particle bombardment , with a view to pyramiding sheath blight and bacterial blight resistance . [ Sen. 5, subscore: 1.00 ]: A transgenic Pusa Basmati1 line pyramided with chi11 , tlp , and Xa21 showed an enhanced resistance to both sheath blight and bacterial blight .
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Score: 2.00 | Title: Proteomic analysis of rice plasma membrane reveals proteins involved in early defense response to bacterial blight .
| Author: Chen F Yuan Y Li Q He Z | Journal: Type: ARTICLE | Literature: oryza Field: abstract Doc ID: pub17407182 | Abstract: Plant plasma membrane ( PM ) proteins play important roles in signal transduction during defense response to an attacking pathogen .
By using an improved method of PM protein preparation and PM-bound green fluorescent protein fusion protein as a visible marker , we conducted PM proteomic analysis of the rice suspension cells expressing the disease resistance gene Xa21 , to identify PM components involved in the early defense response to bacterial blight ( Xanthomonas oryzae pv . oryzae ) .
A total of 20 regulated protein spots were observed on 2-D gels of PM fractions at 12 and 24 h after pathogen inoculation , of which some were differentially regulated between the incompatible and compatible interactions mediated by Xa21 , with good correlation between biological repeats .
Eleven protein spots with predicted functions in plant defense were identified by MS/MS , including nine putative PM-associated proteins H ( + ) -ATPase , protein phosphatase , hypersensitive-induced response protein ( OsHIR1 ) , prohibitin ( OsPHB2 ) , zinc finger and C2 domain protein , universal stress protein ( USP ) , and heat shock protein .
OsHIR1 was modified by the microbal challenge , leading to two differentially accumulated protein spots .
Transcript analysis showed that most of the genes were also regulated at transcriptional levels .
Our study would provide a starting point for functionality of PM proteins in the rice defense .
| Matching Sentences: [ Sen. 2, subscore: 1.00 ]: By using an improved method of PM protein preparation and PM-bound green fluorescent protein fusion protein as a visible marker , we conducted PM proteomic analysis of the rice suspension cells expressing the disease resistance gene Xa21 , to identify PM components involved in the early defense response to bacterial blight ( Xanthomonas oryzae pv . oryzae ) . [ Sen. 3, subscore: 1.00 ]: A total of 20 regulated protein spots were observed on 2-D gels of PM fractions at 12 and 24 h after pathogen inoculation , of which some were differentially regulated between the incompatible and compatible interactions mediated by Xa21 , with good correlation between biological repeats .
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Score: 2.00 | Title: The Xanthomonas oryzae pv . oryzae PhoPQ two-component system is required for AvrXA21 activity , hrpG expression , and virulence .
| Author: Lee SW Jeong KS Han SW Lee SE Phee BK Hahn TR Ronald P | Journal: J Bacteriol Type: MEDLINE | Literature: oryza Field: abstract Doc ID: pub18203830 | Abstract: The rice pathogen recognition receptor , XA21 , confers resistance to Xanthomonas oryzae pv . oryzae strains producing the type one system-secreted molecule , AvrXA21 .
X oryzae pv . oryzae requires a regulatory two-component system ( TCS ) called RaxRH to regulate expression of eight rax ( required for AvrXA21 activity ) genes and to sense population cell density .
To identify other key components in this critical regulatory circuit , we assayed proteins expressed in a raxR gene knockout strain .
This survey led to the identification of the phoP gene encoding a response regulator that is up-regulated in the raxR knockout strain .
Next we generated a phoP knockout strain and found it to be impaired in X oryzae pv . oryzae virulence and no longer able to activate the response regulator HrpG ( hypersensitive reaction and pathogenicity G ) in response to low levels of Ca2+ .
The impaired virulence of the phoP knockout strain can be partially complemented by constitutive expression of hrpG , indicating that PhoP controls a key aspect of X oryzae pv . oryzae virulence through regulation of hrpG .
A gene encoding the cognate putative histidine protein kinase , phoQ , was also isolated .
Growth curve analysis revealed that AvrXA21 activity is impaired in a phoQ knockout strain as reflected by enhanced growth of this strain in rice lines carrying XA21 .
These results suggest that the X oryzae pv . oryzae PhoPQ TCS functions in virulence and in the production of AvrXA21 in partnership with RaxRH .
| Matching Sentences: [ Sen. 1, subscore: 1.00 ]: The rice pathogen recognition receptor , XA21 , confers resistance to Xanthomonas oryzae pv . oryzae strains producing the type one system-secreted molecule , AvrXA21 . [ Sen. 8, subscore: 1.00 ]: Growth curve analysis revealed that AvrXA21 activity is impaired in a phoQ knockout strain as reflected by enhanced growth of this strain in rice lines carrying XA21 .
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Score: 2.00 | Title: Introduction of bacterial blight resistance into Triguna , a high yielding , mid-early duration rice variety .
| Author: Sundaram RM Vishnupriya MR Laha GS Rani NS Rao PS Balachandran SM Reddy GA Sarma NP Sonti RV | Journal: Biotechnol J Type: In-Process | Literature: oryza Field: abstract Doc ID: pub19253322 | Abstract: Bacterial blight ( BB ) is a serious disease of rice in India .
We have used molecular marker-assisted selection in a backcross breeding program to introgress three genes ( Xa21 , xa13 , and xa5 ) for BB resistance into Triguna , a mid-early duration , high yielding rice variety that is susceptible to BB .
At each generation in the backcross program , molecular markers were used to select plants possessing these resistance genes and to select plants that have maximum contribution from the Triguna genome .
A selected BC3F1 plant was selfed to generate homozygous BC ( 3 ) F ( 2 ) plants with different combinations of BB resistance genes .
Plants containing the two-gene combination , Xa21 and xa13 , were found to exhibit excellent resistance against BB .
Single plant selections for superior agronomic characteristics were performed on the progeny of these plants , from BC ( 3 ) F ( 3 ) generation onwards .
The selected plants were subjected to yield trials at the BC ( 3 ) F ( 8 ) generation and were found to have a significant yield advantage over Triguna .
The newly developed lines are being entered into national multi-location field trials .
This work represents a successful example of the application of molecular marker-assisted selection for BB resistance breeding in rice .
| Matching Sentences: [ Sen. 2, subscore: 1.00 ]: We have used molecular marker-assisted selection in a backcross breeding program to introgress three genes ( Xa21 , xa13 , and xa5 ) for BB resistance into Triguna , a mid-early duration , high yielding rice variety that is susceptible to BB . [ Sen. 5, subscore: 1.00 ]: Plants containing the two-gene combination , Xa21 and xa13 , were found to exhibit excellent resistance against BB .
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Score: 2.00 | Title: Effective strategy for pyramiding three bacterial blight resistance genes into fine grain rice cultivar , Samba Mahsuri , using sequence tagged site markers .
| Author: Kottapalli KR Lakshmi Narasu M Jena KK | Journal: Biotechnol Lett Type: MEDLINE | Literature: oryza Field: abstract Doc ID: pub20349335 | Abstract: Bacterial leaf blight ( BB ) of rice is a major disease limiting rice production in several rice growing regions of the world .
The pathogen , Xanthomonas oryzae pv oryzae , causing the disease is highly virulent to rice crops and is capable of evolving new races .
Breeding efforts to incorporate single BB resistant gene often leads to resistance breakdown within a short period .
To overcome such breakdown of resistance and develop germplasm with durable disease resistance , we have introgressed three bacterial blight resistance genes , xa5 , xa13 , and Xa21 into a fine grain rice variety , Samba Mahsuri , using sequence tagged site ( STS ) markers linked to these genes .
Since the efficiency of the STS markers linked to recessive genes to detect homozygotes is less than 100% , we adopted four different pyramiding schemes to minimize loss of recessive resistance genes in advanced backcross generations .
Pyramiding scheme A in which a two-gene Samba Mahsuri pyramid line containing Xa21 and xa5 genes was crossed with the Samba Mahsuri line having xa13 gene alone was found to be most effective in preventing the loss of an important recessive gene xa13 .
We further demonstrated that there was no yield penalty due to pyramiding of multiple genes into the elite indica rice variety .
| Matching Sentences: [ Sen. 4, subscore: 1.00 ]: To overcome such breakdown of resistance and develop germplasm with durable disease resistance , we have introgressed three bacterial blight resistance genes , xa5 , xa13 , and Xa21 into a fine grain rice variety , Samba Mahsuri , using sequence tagged site ( STS ) markers linked to these genes . [ Sen. 6, subscore: 1.00 ]: Pyramiding scheme A in which a two-gene Samba Mahsuri pyramid line containing Xa21 and xa5 genes was crossed with the Samba Mahsuri line having xa13 gene alone was found to be most effective in preventing the loss of an important recessive gene xa13 .
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Score: 2.00 | Title: The Arabidopsis flagellin receptor FLS2 mediates the perception of Xanthomonas Ax21 secreted peptides .
| Author: Danna CH Millet YA Koller T Han SW Bent AF Ronald PC Ausubel FM | Journal: Proc Natl Acad Sci U S A Type: MEDLINE | Literature: oryza Field: abstract Doc ID: pub21576467 | Abstract: Detection of microbes by plants relies in part on an array of pattern-recognition receptors that recognize conserved microbial signatures , so-called "microbe-associated molecular patterns . " The Arabidopsis thaliana receptor-like kinase FLS2 is the pattern-recognition receptor for bacterial flagellin .
Similarly to FLS2 , the rice transmembrane protein XA21 is the receptor for the sulfated form of the Xanthomonas oryzae pv . oryzae secreted protein Ax21 .
Here we show that Ax21-derived peptides activate Arabidopsis immunity , triggering responses similar to those elicited by flagellin , including an oxidative burst , induction of defense-response genes , and enhanced resistance to bacterial pathogens .
To identify Arabidopsis Xa21 functional homologs , we used a reverse genetics approach to screen T-DNA insertion mutants corresponding to all 47 of the Arabidopsis genes encoding non-RD kinases belonging to the interleukin-1 receptor-associated kinase ( IRAK ) family .
Surprisingly , among all of these mutant lines , only fls2 mutants exhibited a significant loss of response to Ax21-derived peptides .
Ax21 peptides also failed to activate defense-related responses in an fls2-24 mutant that does not bind Flg22 .
Moreover , a Flg22Delta2 variant of Flg22 that binds to FLS2 but does not activate FLS2-mediated signaling suppressed Ax21-derived peptide signaling , indicating mutually exclusive perception of Flg22 or Ax21 peptides by FLS2 .
The data indicate that FLS2 functions beyond flagellin perception to detect other microbe-associated molecular patterns .
| Matching Sentences: [ Sen. 2, subscore: 1.00 ]: Similarly to FLS2 , the rice transmembrane protein XA21 is the receptor for the sulfated form of the Xanthomonas oryzae pv . oryzae secreted protein Ax21 . [ Sen. 4, subscore: 1.00 ]: To identify Arabidopsis Xa21 functional homologs , we used a reverse genetics approach to screen T-DNA insertion mutants corresponding to all 47 of the Arabidopsis genes encoding non-RD kinases belonging to the interleukin-1 receptor-associated kinase ( IRAK ) family .
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Score: 2.00 | Title: High-throughput functional marker assay for detection of Xa/xa and fgr genes in rice ( Oryza sativa L ) .
| Author: Salgotra RK Millwood RJ Agarwal S Stewart CN Jr | Journal: Electrophoresis Type: Publisher | Literature: oryza Field: abstract Doc ID: pub21793000 | Abstract: We apply CE for high-throughput analysis of functional markers for marker-assisted selection in rice .
The accuracy , throughput and reproducibility of CE analysis for sequence-tagged site ( STS ) and simple sequence repeat ( SSR ) markers for bacterial blight resistance and aroma genes are demonstrated by using a CE system .
Multiplex PCR products displayed well-differentiated allelic variants using different STS and SSR markers for identification of xa13 , Xa21 and fgr genes using the CE system compared to 1 . 2% agarose gel images .
Moreover , consumption of PCR product is much less in the CE system compared to traditional agarose gel systems .
Sample consumption is less than 0 . 1 muL per analysis , thereby conserving samples for further downstream analysis .
Out of 29 genotypes in BC ( 1 ) F ( 3 ) generation , 16 plants were found homozygous for all the three genes , viz . , xa13 , Xa21 and fgr .
These homozygous lines can be used as potential donors in rice breeding programmes .
| Matching Sentences: [ Sen. 3, subscore: 1.00 ]: Multiplex PCR products displayed well-differentiated allelic variants using different STS and SSR markers for identification of xa13 , Xa21 and fgr genes using the CE system compared to 1 . 2% agarose gel images . [ Sen. 6, subscore: 1.00 ]: Out of 29 genotypes in BC ( 1 ) F ( 3 ) generation , 16 plants were found homozygous for all the three genes , viz . , xa13 , Xa21 and fgr .
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Score: 2.00 | Title: Genetic dissection of the biotic stress response using a genome-scale gene network for rice .
| Author: Lee I Seo YS Coltrane D Hwang S Oh T Marcotte EM Ronald PC | Journal: Proc Natl Acad Sci U S A Type: In-Process | Literature: oryza Field: abstract Doc ID: pub22042862 | Abstract: Rice is a staple food for one-half the worlds population and a model for other monocotyledonous species .
Thus , efficient approaches for identifying key genes controlling simple or complex traits in rice have important biological , agricultural , and economic consequences .
Here , we report on the construction of RiceNet , an experimentally tested genome-scale gene network for a monocotyledonous species .
Many different datasets , derived from five different organisms including plants , animals , yeast , and humans , were evaluated , and 24 of the most useful were integrated into a statistical framework that allowed for the prediction of functional linkages between pairs of genes .
Genes could be linked to traits by using guilt-by-association , predicting gene attributes on the basis of network neighbors .
We applied RiceNet to an important agronomic trait , the biotic stress response .
Using network guilt-by-association followed by focused protein-protein interaction assays , we identified and validated , in planta , two positive regulators , LOC_Os01g70580 ( now Regulator of XA21 ; ROX1 ) and LOC_Os02g21510 ( ROX2 ) , and one negative regulator , LOC_Os06g12530 ( ROX3 ) .
These proteins control resistance mediated by rice XA21 , a pattern recognition receptor .
We also showed that RiceNet can accurately predict gene function in another major monocotyledonous crop species , maize .
RiceNet thus enables the identification of genes regulating important crop traits , facilitating engineering of pathways critical to crop productivity .
| Matching Sentences: [ Sen. 7, subscore: 1.00 ]: Using network guilt-by-association followed by focused protein-protein interaction assays , we identified and validated , in planta , two positive regulators , LOC_Os01g70580 ( now Regulator of XA21 ; ROX1 ) and LOC_Os02g21510 ( ROX2 ) , and one negative regulator , LOC_Os06g12530 ( ROX3 ) . [ Sen. 8, subscore: 1.00 ]: These proteins control resistance mediated by rice XA21 , a pattern recognition receptor .
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Score: 2.00 | Title: Small protein-mediated quorum sensing in a gram-negative bacterium .
| Author: Han SW Sriariyanun M Lee SW Sharma M Bahar O Bower Z Ronald PC | Journal: PLoS One Type: In-Data-Review | Literature: oryza Field: abstract Doc ID: pub22174954 | Abstract: The rice XA21 pattern recognition receptor binds a type I secreted sulfated peptide , called axY ( S ) 22 , derived from the Ax21 ( activator of XA21-mediated immunity ) protein .
The conservation of Ax21 in all sequenced Xanthomonas spp . and closely related genera suggests that Ax21 serves a key biological function .
Here we show that the predicted N-terminal sequence of Ax21 is cleaved prior to secretion outside the cell and that mature Ax21 serves as a quorum sensing ( QS ) factor in Xanthomonas oryzae pv . oryzae .
Ax21-mediated QS controls motility , biofilm formation and virulence .
We provide genetic evidence that the Xoo RaxH histidine kinase serves as the bacterial receptor for Ax21 .
This work establishes a critical role for small protein-mediated QS in a Gram-negative bacterium .
| Matching Sentences: [ Sen. 1, subscore: 2.00 ]: The rice XA21 pattern recognition receptor binds a type I secreted sulfated peptide , called axY ( S ) 22 , derived from the Ax21 ( activator of XA21-mediated immunity ) protein .
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Score: 2.00 | Title: One-step expression and tyrosine O-sulfonation of Ax21 in Escherichia coli .
| Author: Shuguo H Wei Z Chao Z Daoji W | Journal: Appl Biochem Biotechnol Type: MEDLINE | Literature: oryza Field: abstract Doc ID: pub22249854 | Abstract: Ax21 ( activator of Xa21-mediated immunity ) , a pathogen-associated molecular pattern secreted by Xanthomonas oryzae pv . oryzae , can be perceived by a membrane-located pattern recognition receptor Xa21 and triggered immune responses in rice .
An Ax21-derived peptide ( 17-amino acid ) containing a sulfated tyrosine-22 ( axY ( S ) 22 ) is sufficient for Ax21 activity .
Here , we expressed Ax21 and O-sulfated its tyrosine-22 through coexpressing a putative tyrosine sulfotransferase , raxST , and two other genes involved in the synthesis of 3-phosphoadenosine 5-phosphosulfate in Escherichia coli BL21 ( DE3 ) .
The sulfated Ax21 fused with a histidine tag in its N-terminus was extracted and bound onto a Ni-NTA agarose and then cleaved with Factor Xa and CNBr in turn .
Deltaax21Y ( S ) 22 , a 36-amino acid peptide covering axY ( S ) 22 in the lysate supernatant , was finally yielded after ultrafiltration .
The purified peptide was further verified by Tricine-SDS-PAGE and isoelectrofocusing electrophoresis .
Lesion length analysis , reactive oxygen species production , and mitogen-activated protein kinase ( MAPK ) activation of rice leaves inoculated with Deltaax21Y ( S ) 22 confirmed the activity of the sulfated peptide .
Overall , this study successfully established an efficient system for expression and purification of a sulfated peptide .
In addition , the sulfotransferase activity of RaxST was confirmed for the first time .
| Matching Sentences: [ Sen. 1, subscore: 2.00 ]: Ax21 ( activator of Xa21-mediated immunity ) , a pathogen-associated molecular pattern secreted by Xanthomonas oryzae pv . oryzae , can be perceived by a membrane-located pattern recognition receptor Xa21 and triggered immune responses in rice .
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Score: 2.00 | Title: Metaphase and interphase fluorescence in situ hybridization mapping of the rice genome with bacterial artificial chromosomes .
| Author: Jiang J Gill BS Wang GL Ronald PC Ward DC .
| Journal: Proc . Natl . Acad . Sci . USA Type: ARTICLE | Literature: oryza Field: abstract Doc ID: pub7753830 | Abstract: Fluorescence in situ hybridization ( FISH ) is a powerful tool for physical mapping in human and other mammalian species .
However , application of the FISH technique has been limited in plant species , especially for mapping single or low-copy DNA sequences , due to inconsistent signal production in plant chromosome preparations .
Here we demonstrate that bacterial artificial chromosome ( BAC ) clones can be mapped readily on rice ( Oryza sativa L ) chromosomes by FISH .
Repetitive DNA sequences in BAC clones can be suppressed efficiently by using rice genomic DNA as a competitor in the hybridization mixture .
BAC clones as small as 40 kb were successfully mapped .
To demonstrate the application of the FISH technique in physical mapping of plant genomes , both anonymous BAC clones and clones closely linked to a rice bacterial blight-resistance locus , Xa21 , were chosen for analysis .
The physical location of Xa21 and the relationships among the linked clones were established , thus demonstrating the utility of FISH in plant genome analysis . | Matching Sentences: [ Sen. 6, subscore: 1.00 ]: To demonstrate the application of the FISH technique in physical mapping of plant genomes , both anonymous BAC clones and clones closely linked to a rice bacterial blight-resistance locus , Xa21 , were chosen for analysis . [ Sen. 7, subscore: 1.00 ]: The physical location of Xa21 and the relationships among the linked clones were established , thus demonstrating the utility of FISH in plant genome analysis .
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Score: 2.00 | Title: The cloned gene , Xa21 , confers resistance to multiple Xanthomonas oryzae pv . oryzae isolates in transgenic plants .
| Author: Wang GL Song WY Ruan DL Sideris S Ronald PC .
| Journal: Mol .
Plant Microbe Interact .
Type: ARTICLE | Literature: oryza Field: abstract Doc ID: pub8969533 | Abstract: The cloned rice gene , Xa21 , confers resistance to multiple pathogen isolates of Xanthomonas oryzae pv . oryzae in transgenic plants .
The resistance phenotype was stably transmitted to T1 progeny and inherited as a single locus .
The T1 progeny were tested for resistance to 32 X oryzae pv . oryzae isolates from eight countries .
Both the engineered line and the donor line showed resistance to 29 isolates and susceptibility to three isolates .
The identical resistance spectrum of both lines indicates that the presence of a single member of a multigene family , Xa21 , is sufficient to confer multi-isolate resistance .
The results presented here have important implications for engineering disease resistance in crop plants . | Matching Sentences: [ Sen. 1, subscore: 1.00 ]: The cloned rice gene , Xa21 , confers resistance to multiple pathogen isolates of Xanthomonas oryzae pv . oryzae in transgenic plants . [ Sen. 5, subscore: 1.00 ]: The identical resistance spectrum of both lines indicates that the presence of a single member of a multigene family , Xa21 , is sufficient to confer multi-isolate resistance .
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Score: 2.00 | Title: Evolution of the rice Xa21 disease resistance gene family .
| Author: Song WY Pi LY Wang GL Gardner J Holsten T Ronald PC .
| Journal: Plant Cell Type: ARTICLE | Literature: oryza Field: abstract Doc ID: pub9286106 | Abstract: The rice disease resistance gene Xa21 , encoding a receptor-like kinase , is a member of a multigene family .
Sequence analysis of seven family members revealed two distinct classes of genes .
One member from each class encodes a receptor kinase-like open reading frame .
The other five members encode truncated open reading frames of the predicted receptor kinase .
A highly conserved 233-bp sequence ( HC ) was also identified among the seven family members .
Recombination at the HC region between family members apparently resulted in the precise swapping of promoter regions .
Large sequence duplications were generated by a presumed unequal crossover event in intergenic regions .
Insertions of transposon-like sequences truncated two of the predicted open reading frames .
A model for amplification and diversification of the Xa21 gene family is presented . | Matching Sentences: [ Sen. 1, subscore: 1.00 ]: The rice disease resistance gene Xa21 , encoding a receptor-like kinase , is a member of a multigene family . [ Sen. 9, subscore: 1.00 ]: A model for amplification and diversification of the Xa21 gene family is presented .
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Score: 2.00 | Title: Identification and characterization of 14 transposon-like elements in the noncoding regions of members of the Xa21 family of disease resistance genes in rice .
| Author: Song WY Pi LY Bureau TE Ronald PC .
| Journal: Mol . Gen . Genet . Type: ARTICLE | Literature: oryza Field: abstract Doc ID: pub9669326 | Abstract: The rice disease resistance gene Xa21 , which encodes a receptor-like kinase , is a member of a multigene family .
Based on comparisons of genomic sequences of seven family members , seventeen transposon-like elements were identified in the 5 and 3 flanking regions and introns of these genes .
Sequence characterization revealed that these elements are diverse , showing similarity to maize Ds , CACTA and miniature inverted repeat-like elements , as well as novel elements .
Only two elements were located in presumed coding regions , indicating that integration of transposable elements at the Xa21 disease resistance locus occurred preferentially in noncoding regions . | Matching Sentences: [ Sen. 1, subscore: 1.00 ]: The rice disease resistance gene Xa21 , which encodes a receptor-like kinase , is a member of a multigene family . [ Sen. 4, subscore: 1.00 ]: Only two elements were located in presumed coding regions , indicating that integration of transposable elements at the Xa21 disease resistance locus occurred preferentially in noncoding regions .
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Score: 2.00 | Title: Analysis of T-DNA Xa21 loci and bacterial blight resistance effects of the transgene Xa21 in transgenic rice .
| Author: Zhai W Chen C Zhu X Chen X Zhang D Li X Zhu L | Journal: Theor . Appl . Genet . Type: ARTICLE | Literature: oryza Field: title Doc ID: pub15088086 | Abstract: The genetic loci and phenotypic effects of the transgene Xa21 , a bacterial blight ( BB ) resistance gene cloned from rice , were investigated in transgenic rice produced through an Agrobacterium-mediated transformation system .
The flanking sequences of integrated T-DNAs were isolated from Xa21 transgenic rice lines using thermal asymmetric interlaced PCR .
Based on the analysis of 24 T-DNA Xa21 flanking sequences , T-DNA loci in rice could be classified into three types : the typical T-DNA integration with the definite left and right borders , the T-DNA integration linked with the adjacent vector backbone sequences and the T-DNA integration involved in a complicated recombination in the flanking sequences .
The T-DNA integration in rice was similar to that in dicotyledonous genomes but was significantly different from the integration produced through direct DNA transformation approaches .
All three types of integrated transgene Xa21 could be stably inherited and expressed the BB resistance through derived generations in their respective transgenic lines .
The flanking sequences of the typical T-DNA integration consisted of actual rice genomic DNA and could be used as probes to locate the transgene on the rice genetic map .
A total of 15 different rice T-DNA flanking sequences were identified .
They displayed restriction fragment length polymorphisms ( RFLPs ) between two rice varieties , ZYQ8 and JX17 , and were mapped on rice chromosomes 1 , 3 , 4 , 5 , 7 , 9 , 10 , 11 and 12 , respectively , by using a double haploid population derived from a cross between ZYQ8 and JX17 .
The blast search and homology comparison of the rice T-DNA flanking sequences with the rice chromosome-anchored sequence database confirmed the RFLP mapping results .
On the basis of genetic mapping of the T-DNA Xa21 loci , the BB resistance effects of the transgene Xa21 at different chromosome locations were investigated using homozygous transgenic lines with only one copy of the transgene .
Among the transgenic lines , no obvious position effects of the transgene Xa21 were observed .
In addition , the BB resistance levels of the Xa21 transgenic plants with different transgene copy numbers and on different genetic backgrounds were also investigated .
It was observed that genetic background ( or genome ) effects were more obvious than dosage effects and position effects on the BB resistance level of the transgenic plants . | Matching Sentences: [ Sen. 1, subscore: 2.00 ]: Analysis of T-DNA Xa21 loci and bacterial blight resistance effects of the transgene Xa21 in transgenic rice .
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Score: 2.00 | Title: Rice XA21 Binding Protein 3 Is a Ubiquitin Ligase Required for Full Xa21-Mediated Disease Resistance .
| Author: Wang YS Pi LY Chen X Chakrabarty PK Jiang J De Leon AL Liu GZ Li L Benny U Oard J Ronald PC Song WY .
| Journal: Type: ARTICLE | Literature: oryza Field: title Doc ID: pub17172358 | Abstract: XA21 is a receptor-like kinase protein in rice ( Oryza sativa ) that confers gene-for-gene resistance to specific races of the causal agent of bacterial blight disease , Xanthomonas oryzae pv oryzae .
We identified XA21 binding protein 3 ( XB3 ) , an E3 ubiquitin ligase , as a substrate for the XA21 Ser and Thr kinase .
The interaction between XB3 and the kinase domain of XA21 has been shown in yeast and in vitro , and the physical association between XB3 and XA21 in vivo has also been confirmed by coimmunoprecipitation assays .
XB3 contains an ankyrin repeat domain and a RING finger motif that is sufficient for its interaction with the kinase domain of XA21 and for its E3 ubiquitin ligase activity , respectively .
Transgenic plants with reduced expression of the Xb3 gene are compromised in resistance to the avirulent race of X oryzae pv oryzae .
Furthermore , reduced levels of Xb3 lead to decreased levels of the XA21 protein .
These results indicate that Xb3 is necessary for full accumulation of the XA21 protein and for Xa21-mediated resistance . | Matching Sentences: [ Sen. 1, subscore: 2.00 ]: Rice XA21 Binding Protein 3 Is a Ubiquitin Ligase Required for Full Xa21-Mediated Disease Resistance .
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Score: 2.00 | Title: A conserved threonine residue in the juxtamembrane domain of the XA21 pattern recognition receptor is critical for kinase autophosphorylation and XA21-mediated immunity .
| Author: Chen X Chern M Canlas PE Jiang C Ruan D Cao P Ronald PC | Journal: J Biol Chem Type: MEDLINE | Literature: oryza Field: title Doc ID: pub20118235 | Abstract: Despite the key role that pattern recognition receptors ( PRRs ) play in regulating immunity in plants and animals , the mechanism of activation of the associated non-arginine-aspartate ( non-RD ) kinases is unknown .
The rice PRR XA21 recognizes the pathogen-associated molecular pattern , Ax21 ( activator of XA21-mediated immunity ) .
Here we show that the XA21 juxtamembrane ( JM ) domain is required for kinase autophosphorylation .
Threonine 705 in the XA21 JM domain is essential for XA21 autophosphorylation in vitro and XA21-mediated innate immunity in vivo .
The replacement of Thr ( 705 ) by an alanine or glutamic acid abolishes XA21 autophosphorylation and eliminates interactions between XA21 and four XA21-binding proteins in yeast and rice .
Although threonine residues analogous to Thr ( 705 ) of XA21 are present in the JM domains of most RD and non-RD plant receptor-like kinases , this residue is not required for autophosphorylation of the Arabidopsis RD RLK BRI1 ( brassinosteroid insensitive 1 ) .
The threonine 705 of XA21 is conserved only in the JM domains of plant RLKs but not in those of fly , human , or mouse suggesting distinct regulatory mechanisms .
These results contribute to growing knowledge regarding the mechanism by which non-RD RLKs function in plant .
| Matching Sentences: [ Sen. 1, subscore: 2.00 ]: A conserved threonine residue in the juxtamembrane domain of the XA21 pattern recognition receptor is critical for kinase autophosphorylation and XA21-mediated immunity .
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Score: 2.00 | Title: An ATPase promotes autophosphorylation of the pattern recognition receptor XA21 and inhibits XA21-mediated immunity .
| Author: Chen X Chern M Canlas PE Ruan D Jiang C Ronald PC | Journal: Proc Natl Acad Sci U S A Type: MEDLINE | Literature: oryza Field: title Doc ID: pub20385831 | Abstract: Cell-surface pattern recognition receptors ( PRRs ) are key components of the innate immune response in animals and plants .
These receptors typically carry or associate with non-RD kinases to control early events of innate immunity signaling .
Despite their importance , the mode of regulation of PRRs is largely unknown .
Here we show that the rice PRR , XA21 , interacts with XA21 binding protein 24 ( XB24 ) , a previously undescribed ATPase .
XB24 promotes autophosphorylation of XA21 through its ATPase activity .
Rice lines silenced for Xb24 display enhanced XA21-mediated immunity , whereas rice lines overexpressing XB24 are compromised for immunity .
XB24 ATPase enzyme activity is required for XB24 function .
XA21 is degraded in the presence of the pathogen-associated molecular pattern Ax21 when XB24 is overexpressed .
These results demonstrate a function for this large class of broadly conserved ATPases in PRR-mediated immunity .
| Matching Sentences: [ Sen. 1, subscore: 2.00 ]: An ATPase promotes autophosphorylation of the pattern recognition receptor XA21 and inhibits XA21-mediated immunity .
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Score: 1.00 | Title: Expression of a gibberellin-induced leucine-rich repeat receptor-like protein kinase in deepwater rice and its interaction with kinase-associated protein phosphatase .
| Author: van der Knaap E Song WY Ruan DL Sauter M Ronald PC Kende H | Journal: Plant Physiol .
Type: ARTICLE | Literature: oryza Field: abstract Doc ID: pub10364408 | Abstract: We identified in deepwater rice ( Oryza sativa L ) a gene encoding a leucine-rich repeat receptor-like transmembrane protein kinase , OsTMK ( O sativa transmembrane kinase ) .
The transcript levels of OsTMK increased in the rice internode in response to gibberellin .
Expression of OsTMK was especially high in regions undergoing cell division and elongation .
The kinase domain of OsTMK was enzymatically active , autophosphorylating on serine and threonine residues .
A cDNA encoding a rice ortholog of a kinase-associated type 2C protein phosphatase ( OsKAPP ) was cloned .
KAPPs are putative downstream components in kinase-mediated signal transduction pathways .
The kinase interaction domain of OsKAPP was phosphorylated in vitro by the kinase domain of OsTMK .
RNA gel-blot analysis indicated that the expression of OsTMK and OsKAPP was similar in different it issues of the rice plant .
In protein-binding assays , OsKAPP interacted with a receptor-like protein kinase , RLK5 of Arabidopsis , but not with the protein kinase domains of the rice and maize receptor-like protein kinases Xa21 and ZmPK1 , respectively . | Matching Sentences: [ Sen. 9, subscore: 1.00 ]: In protein-binding assays , OsKAPP interacted with a receptor-like protein kinase , RLK5 of Arabidopsis , but not with the protein kinase domains of the rice and maize receptor-like protein kinases Xa21 and ZmPK1 , respectively .
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Score: 1.00 | Title: Perception of brassinosteroids by the extracellular domain of the receptor kinase BRI1 .
| Author: He Z Wang ZY Li J Zhu Q Lamb C Ronald P Chory J | Journal: Science Type: ARTICLE | Literature: oryza Field: abstract Doc ID: pub10875920 | Abstract: An assay was developed to study plant receptor kinase activation and signaling mechanisms .
The extracellular leucine-rich repeat ( LRR ) and transmembrane domains of the Arabidopsis receptor kinase BRI1 , which is implicated in brassinosteroid signaling , were fused to the serine/threonine kinase domain of XA21 , the rice disease resistance receptor .
The chimeric receptor initiates plant defense responses in rice cells upon treatment with brassinosteroids .
These results , which indicate that the extracellular domain of BRI1 perceives brassinosteroids , suggest a general signaling mechanism for the LRR receptor kinases of plants .
This system should allow the discovery of ligands for the LRR kinases , the largest group of plant receptor kinases . | Matching Sentences: [ Sen. 2, subscore: 1.00 ]: The extracellular leucine-rich repeat ( LRR ) and transmembrane domains of the Arabidopsis receptor kinase BRI1 , which is implicated in brassinosteroid signaling , were fused to the serine/threonine kinase domain of XA21 , the rice disease resistance receptor .
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Score: 1.00 | Title: The rice Rim2 transcript accumulates in response to Magnaporthe grisea and its predicted protein product shares similarity with TNP2-like proteins encoded by CACTA transposons .
| Author: He ZH Dong HT Dong JX Li DB Ronald PC .
| Journal: Mol . Gen . Genet . Type: ARTICLE | Literature: oryza Field: abstract Doc ID: pub11016827 | Abstract: A rice transcript , Rim2 , was identified that accumulated in both incompatible and compatible interactions between rice and Magnaporthe grisea .
The Rim2 transcript also accumulated in response to treatment with a cell wall elicitor derived from M grisea .
A 3 . 3-kb RIM2 cDNA clone was isolated and is predicted to encode a protein of 653 amino acids , which shares 32 55% identity with TNP2-like proteins encoded by CACTA transposons of other plants .
A 1 . 05-kb segment of the Rim2 sequence shows 82% nucleotide sequence identity with sequences flanking the A1 and C members of the rice Xa21 disease resistance gene family .
The 5-upstream region of Rim2 was cloned and the transcriptional start sites were identified .
The 5 and 3 noncoding termini of Rim2 are AT-rich .
A cis-element showing similarity to a sequence that mediates defense-associated transcriptional activation of the tobacco retrotransposon Tnt1 , and four motifs that fit the consensus sequence of the elicitor-responsive elements in the promoters of the parsley PR-1 genes were found in the 5-upstream region .
Four imperfect tandem repeats were identified in the 3 noncoding terminus .
Southern analysis with genomic DNA from different rice species indicated that Rim2 is present in 3-4 copies per genome .
These results suggest that Rim2 may be one component of a large CACTA-like element , whose transcript accumulates in response to attack by pathogens . | Matching Sentences: [ Sen. 4, subscore: 1.00 ]: A 1 . 05-kb segment of the Rim2 sequence shows 82% nucleotide sequence identity with sequences flanking the A1 and C members of the rice Xa21 disease resistance gene family .
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Score: 1.00 | Title: Construction of a 1 . 2-Mb contig including the citrus tristeza virus resistance gene locus using a bacterial artificial chromosome library of Poncirus trifoliata ( L ) Raf .
| Author: Yang ZN Ye XR Choi S Molina J Moonan F Wing RA Roose ML Mirkov TE .
| Journal: Genome Type: ARTICLE | Literature: oryza Field: abstract Doc ID: pub11444697 | Abstract: The citrus tristeza virus resistance gene ( Ctv ) is a single dominant gene in Poncirus trifoliata , a sexually compatible relative of citrus .
To clone this gene , a bacterial artificial chromosome ( BAC ) library has been constructed from an individual plant that was homozygous for Ctv .
This library contains 45 , 696 clones with an average insert size of 80 kb , corresponding to 9 . 6 genome equivalents .
Screening of the BAC library with five chloroplast DNA probes indicated that 0 . 58% of the BAC clones contained chloroplast-derived inserts .
The chromosome walk across the Ctv locus was initiated using three closely linked genetic markers : C19 , AD8 , and Z16 .
The walk has been completed and a contig of ca 1 . 2 Mb was constructed .
Based on new data , the genetic map in the Ctv region was revised , with Ctv being located between AD8-Z16 and C19 at distances of 1 . 2 and 0 . 6 cM , respectively .
Utilizing DNA fragments isolated from the contig as RFLP markers , the Ctv locus was further mapped to a region of ca 300 kb .
This contig contains several putative disease-resistance genes similar to the rice Xa21 gene , the tomato Cf-2 gene , and the Arabidopsis thaliana RPS2 gene .
This library will therefore allow cloning of Ctv and other putative disease-resistance genes .
| Matching Sentences: [ Sen. 9, subscore: 1.00 ]: This contig contains several putative disease-resistance genes similar to the rice Xa21 gene , the tomato Cf-2 gene , and the Arabidopsis thaliana RPS2 gene .
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Score: 1.00 | Title: [ Genome analysis of transgenic homozygous line "Minghui 63-Xa21" ] | Author: Xie B Zhu XF Zhai WX Lu RL Zhu LH .
| Journal: Sheng Wu Gong Cheng Xue Bao Type: ARTICLE | Literature: oryza Field: abstract Doc ID: pub11977586 | Abstract: By using rice SSRP , RAPD and AFLP molecular markers , the genome of rice transgenic line "Minghui 63-Xa21" was analyzed .
32 SSRP primers , 42 RAPD primers and 8 AFLP primers could produce obvious PCR bands in the analysis of at least 12 individual plants selected randomly from "Minghui 63-Xa21" T3 generation .
Totally 550 PCR bands , equivalent to 550 genomic sites , were detected .
Different individual plants of the transgenic homozygous line displayed almost the same PCR pattern .
Compared with the control "Minghui 63" , no difference was found in their PCR patterns .
This indicated that the introduction of Xa21 into the genome of "Minghui 63" did not change these 550 genome sites and their heredity .
Very few variant PCR bands were observed in some individual plants from both "Minghui 63-Xa21" and "Minghui 63" .
However , the variant percentage was equivalent between the transgenic line and the non-transgenic control line . | Matching Sentences: [ Sen. 6, subscore: 1.00 ]: This indicated that the introduction of Xa21 into the genome of "Minghui 63" did not change these 550 genome sites and their heredity .
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Score: 1.00 | Title: Pyramiding transgenes for multiple resistance in rice against bacterial blight , yellow stem borer and sheath blight .
| Author: Datta K Baisakh N Thet KM Tu J Datta SK .
| Journal: Theor . Appl . Genet . Type: ARTICLE | Literature: oryza Field: abstract Doc ID: pub12582865 | Abstract: Here we describe the development of transgene-pyramided stable elite rice lines resistant to disease and insect pests by conventional crossing of two transgenic parental lines transformed independently with different genes .
The Xa21 gene ( resistance to bacterial blight ) , the Bt fusion gene ( for insect resistance ) and the chitinase gene ( for tolerance of sheath blight ) were combined in a single rice line by reciprocal crossing of two transgenic homozygous IR72 lines .
F4 plant lines carrying all the genes of interest stably were identified using molecular methods .
The identified lines , when exposed to infection caused by Xanthomonas oryzae pv oryzae , showed resistance to bacterial blight .
Neonate larval mortality rates of yellow stem borer ( Scirpophaga incertulas ) in an insect bioassay of the same identified lines were 100% .
The identified line pyramided with different genes to protect against yield loss showed high tolerance of sheath blight disease caused by Rhizoctonia solani . | Matching Sentences: [ Sen. 2, subscore: 1.00 ]: The Xa21 gene ( resistance to bacterial blight ) , the Bt fusion gene ( for insect resistance ) and the chitinase gene ( for tolerance of sheath blight ) were combined in a single rice line by reciprocal crossing of two transgenic homozygous IR72 lines .
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Score: 1.00 | Title: Isolation and linkage analysis of expressed disease-resistance gene analogues of sugar beet ( Beta vulgaris L ) .
| Author: Hunger S Di Gaspero G Mhring S Bellin D Schfer-Pregl R Borchardt DC Durel CE Werber M Weisshaar B Salamini F Schneider K | Journal: Genome Type: ARTICLE | Literature: oryza Field: abstract Doc ID: pub12669798 | Abstract: Sequence conservation among resistance genes ( R genes ) was exploited to identify 47 R gene analogues ( RGAs ) from sugar beet ( Beta vulgaris L ) .
Using degenerate primers , 11 RGAs were amplified from genomic DNA and 7 from leaf or beet cDNA .
Twenty-nine were selected from an EST sequencing program .
Twenty-one RGAs contained structures similar to the nucleotide binding site ( NBS ) --leucine rich repeat ( LRR ) domain , a motif commonly found in several R genes .
Among the remaining RGAs , 19 revealed similarity to the serine ( threonine ) protein kinase domain of R genes , 4 showed features related to the LRR region of the rice disease resistance gene Xa21 , 1 RGA resembled the sugar beet nematode resistance gene Hs1pro-1 , and 2 had homologies to other gene products associated with disease resistance .
For 20 EST-derived RGAs , transcript levels were compared in leaf and root it issue revealing organ-specific transcription in 7 cases .
Thirty-three RGAs were spread over all nine sugar beet chromosomes , except for a cluster of nine closely linked RGAs on chromosome 7 .
The analysis of linkage between RGAs and loci for rhizomania and Cercospora resistance identified alleles associated with resistance in both cases .
| Matching Sentences: [ Sen. 5, subscore: 1.00 ]: Among the remaining RGAs , 19 revealed similarity to the serine ( threonine ) protein kinase domain of R genes , 4 showed features related to the LRR region of the rice disease resistance gene Xa21 , 1 RGA resembled the sugar beet nematode resistance gene Hs1pro-1 , and 2 had homologies to other gene products associated with disease resistance .
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Score: 1.00 | Title: Cytological and molecular analysis of the Hordeum vulgare-Puccinia triticina nonhost interaction .
| Author: Neu C Keller B Feuillet C | Journal: Mol .
Plant Microbe Interact .
Type: ARTICLE | Literature: oryza Field: abstract Doc ID: pub12848428 | Abstract: Cultivated barley , Hordeum vulgare L , is considered to be a nonhost or intermediate host species for the wheat leaf rust fungus Puccinia triticina .
Here , we have investigated , at the microscopic and molecular levels , the reaction of barley cultivars to wheat leaf rust infection .
In the nonhost resistant cultivar Cebada Capa , abortion of fungal growth occurred at both pre and posthaustorial stages , suggesting that defense genes are expressed throughout the development of the inappropriate fungus during the nonhost resistance reaction .
In the two barley lines L94 and Bowman , a low level of prehaustorial resistance to P triticina was observed and susceptibility was comparable to that of wheat control plants .
Suppression subtractive hybridization was used to identify genes that are differentially expressed during the nonhost resistance reaction in Cebada Capa as well as during the successful establishment of the inappropriate wheat leaf rust fungus in L94 .
Northern analysis indicated that two candidate genes , including a barley ortholog of the rice resistance gene Xa21 , are putatively involved in nonhost and non-race-specific resistance reactions .
In addition , a new gene that is specifically induced during the successful development of the inappropriate fungus P triticina in barley has been identified .
| Matching Sentences: [ Sen. 6, subscore: 1.00 ]: Northern analysis indicated that two candidate genes , including a barley ortholog of the rice resistance gene Xa21 , are putatively involved in nonhost and non-race-specific resistance reactions .
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Score: 1.00 | Title: Isolation and characterization of novel defense response genes involved in compatible and incompatible interactions between rice and Magnaporthe grisea .
| Author: Lu G Jantasuriyarat C Zhou B Wang GL .
| Journal: Theor . Appl . Genet . Type: ARTICLE | Literature: oryza Field: abstract Doc ID: pub14605807 | Abstract: To identify early-induced defense genes involved in broad-spectrum resistance to rice blast , suppression subtractive hybridization was used to generate two cDNA libraries enriched for transcripts differentially expressed in Pi9 ( t ) -resistant and -susceptible plants .
After differential screening by membrane-based hybridization and subsequent confirmation by reverse Northern blot analysis , selected clones were sequenced and analyzed .
Forty-seven unique cDNA clones were found and assigned to eight different groups according to the putative function of their homologous genes in the database .
These genes may be involved in pathogen or stress response , signal transduction , transcription , cell transport , metabolism , energy or protein destination .
Northern blot analysis showed that most of these genes were induced or suppressed after blast infection , and that half of them showed differential expression patterns between compatible and incompatible interactions .
Interestingly , all but one of the identified genes are reported here for the first time to be involved in defense response to rice blast In addition , hybridization of these clones with cDNAs synthesized from RNA samples from bacterial blight-infected leaves showed that few of them are induced or repressed in Xa21 or Xa7-resistant plants , suggesting a minimum overlap of defense responses mediated by different resistance genes to fungal and bacterial pathogens at an early stage of infection .
Further characterization and functional analysis of these genes will enhance our understanding of the molecular mechanism of broad-spectrum resistance in rice . | Matching Sentences: [ Sen. 6, subscore: 1.00 ]: Interestingly , all but one of the identified genes are reported here for the first time to be involved in defense response to rice blast In addition , hybridization of these clones with cDNAs synthesized from RNA samples from bacterial blight-infected leaves showed that few of them are induced or repressed in Xa21 or Xa7-resistant plants , suggesting a minimum overlap of defense responses mediated by different resistance genes to fungal and bacterial pathogens at an early stage of infection .
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Score: 1.00 | Title: Characterisation of early transcriptional changes involving multiple signalling pathways in the Mla13 barley interaction with powdery mildew ( Blumeria graminis f . sp . hordei ) .
| Author: Hein I Campbell EI Woodhead M Hedley PE Young V Morris WL Ramsay L Stockhaus J Lyon GD Newton AC Birch PR .
| Journal: Planta Type: ARTICLE | Literature: oryza Field: abstract Doc ID: pub14648226 | Abstract: Suppression subtractive hybridisation was used to isolate 21 cDNAs ( bmi1 bmi21 ) up-regulated 1-5 h post-inoculation ( hpi ) in a barley ( Hordeum vulgare L cv .
Pallas ) near-isogenic line ( NIL ) P11 ( Mla13 ) challenged with either avirulent or virulent isolates of Blumeria graminis f . sp . hordei .
Transcriptional changes at these time-points are crucial for the Mla-mediated hypersensitive response [ WR Bushnell and Z Liu ( 1994 ) Physiol Mol Plant Pathol 44 : 389-402 ] .
Seven sequences were up-regulated by 1 hpi , when the pathogen has formed only the primary germ tube .
Some transcripts were similar to genes with a role in regulating programmed cell death in animals , including NF kappaB and oxysterol-binding protein .
Moreover , bmi7 , similar to rice resistance gene Xa21 , was rapidly up-regulated in both compatible and incompatible interactions , but was then down-regulated by 5 hpi in the virulent interaction .
Only nine of the transcripts were up-regulated in mlo5 resistance in cv .
Pallas NIL P22 , confirming differential pathway induction between Mla13 and mlo5 .
However , eight sequences up-regulated in the Mla13 response in P11 were already highly elevated in uninoculated mlo5 mutant P22 , suggesting that they may be negatively regulated by wild-type Mlo .
Regulation of bmi sequences was investigated using salicylic acid , methyl jasmonate , ethylene , H ( 2 ) O ( 2 ) , abscisic acid , wounding and a glucan elicitor .
No single stimulus up-regulated all genes , suggesting either combinations of these stimuli , or additional stimuli , are involved in early Mla13 and mlo5 resistances .
Whereas H ( 2 ) O ( 2 ) up or down-regulated 17 of the transcripts detected in Northern analyses , salicylic acid stimulated only down-regulation of 5 transcripts .
| Matching Sentences: [ Sen. 6, subscore: 1.00 ]: Moreover , bmi7 , similar to rice resistance gene Xa21 , was rapidly up-regulated in both compatible and incompatible interactions , but was then down-regulated by 5 hpi in the virulent interaction .
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Score: 1.00 | Title: Bacterial artificial chromosome ( BAC ) library resource for positional cloning of pest and disease resistance genes in cassava ( Manihot esculenta Crantz ) .
| Author: Tomkins J Fregene M Main D Kim H Wing R Tohme J | Journal: Plant Mol . Biol . Type: ARTICLE | Literature: oryza Field: abstract Doc ID: pub15630619 | Abstract: Pest and disease problems are important constraints of cassava production and host plant resistance is the most efficient method of combating them .
Breeding for host plant resistance is considerably slowed down by the crops biological constraints of a long growth cycle , high levels of heterozygosity and a large genetic load .
More efficient methods such as gene cloning and transgenesis are required to deploy resistance genes .
To facilitate the cloning of resistance genes , bacterial artificial chromosome ( BAC ) library resources have been developed for cassava .
Two libraries were constructed from the cassava clones , TMS 30001 , resistant to the cassava mosaic disease ( CMD ) and the cassava bacterial blight ( CBB ) , and MECU72 , resistant to cassava white fly .
The TMS30001 library has 55 , 296 clones with an insert size range of 40-150 kb with an average of 80 kb , while the MECU72 library consists of 92 160 clones and an insert size range of 25-250 kb average of 93 kb .
Based on a genome size of 772 Mb , the TMS30001 and MECU72 libraries have a 5 and 11 . 3 haploid genome equivalents and a 95 and 99 chance of finding any sequence , respectively .
To demonstrate the potential of the libraries , the TMS30001 library was screened by southern hybridization using a cassava analog ( CBB1 ) of the Xa21 gene from rice that maps to a region containing a QTL for resistance to CBB as probe .
Five BAC clones that hybridized to CBB1 were isolated and a Hind III fingerprint revealed 2-3 copies of the gene in individual BAC clones .
A larger scale analysis of resistance gene analogs ( RGAs ) in cassava has also been conducted in order to understand the number and organization of RGAs .
To scan for gene and repeat DNA content in the libraries , end-sequencing was performed on 2 , 301 clones from the MECU72 library .
A total of 1705 unique sequences were obtained with an average size of 715 bp .
Database homology searches using BLAST revealed that 458 sequences had significant homology with known proteins and 321 with transposable elements .
The use of the library in positional cloning of pest and disease resistance genes is discussed .
| Matching Sentences: [ Sen. 8, subscore: 1.00 ]: To demonstrate the potential of the libraries , the TMS30001 library was screened by southern hybridization using a cassava analog ( CBB1 ) of the Xa21 gene from rice that maps to a region containing a QTL for resistance to CBB as probe .
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Score: 1.00 | Title: Plant and animal pathogen recognition receptors signal through non-RD kinases .
| Author: Dardick C Ronald P | Journal: PLoS Pathog .
Type: ARTICLE | Literature: oryza Field: abstract Doc ID: pub16424920 | Abstract: Plants and animals mediate early steps of the innate immune response through pathogen recognition receptors ( PRRs ) .
PRRs commonly associate with or contain members of a monophyletic group of kinases called the interleukin-1 receptor-associated kinase ( IRAK ) family that include Drosophila Pelle , human IRAKs , rice XA21 and Arabidopsis FLS2 .
In mammals , PRRs can also associate with members of the receptor-interacting protein ( RIP ) kinase family , distant relatives to the IRAK family .
Some IRAK and RIP family kinases fall into a small functional class of kinases termed non-RD , many of which do not autophosphorylate the activation loop .
We surveyed the yeast , fly , worm , human , Arabidopsis , and rice kinomes ( 3 , 723 kinases ) and found that despite the small number of non-RD kinases in these genomes ( 9%-29% ) , 12 of 15 kinases known or predicted to function in PRR signaling fall into the non-RD class .
These data indicate that kinases associated with PRRs can largely be predicted by the lack of a single conserved residue and reveal new potential plant PRR subfamilies . | Matching Sentences: [ Sen. 2, subscore: 1.00 ]: PRRs commonly associate with or contain members of a monophyletic group of kinases called the interleukin-1 receptor-associated kinase ( IRAK ) family that include Drosophila Pelle , human IRAKs , rice XA21 and Arabidopsis FLS2 .
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Score: 1.00 | Title: Cloning and expression of resistance gene analogs ( RGAs ) from wild banana resistant to banana Fusarium wilt .
| Author: Chen YP Chen YF Zhao JT Huang X Huang XL | Journal: Zhi Wu Sheng Li Yu Fen Zi Sheng Wu Xue Xue Bao Type: In-Process | Literature: oryza Field: abstract Doc ID: pub18349511 | Abstract: Wild banana species are essential natural gene pools for banana improvement .
In this study , six RGAs about 500 bp were obtained from leaves of Musa acuminata , a wild banana shown to be resistant to banana Fusarium wilt race 4 , by PCR amplification with degenerate primers designed according to the conserved NBS motif and serine/threonine kinase domain of plant resistance ( R ) genes .
Among these RGAs , the deduced amino acids of WNB1 and WNB2 contain NB-ARC domain and WNB1 can be translated into polypeptide uninterrupted by stop codons .
The deduced amino acids of other four RGAs ( WST1 , WST2 , WST3 and WST4 ) all contain the serine/threonine kinase domain and WST3 encodes a polypeptide homologous to that of bacterial blight resistance gene Xa21 of rice .
At different time after inoculation with Fusarium oxysporum f . sp . cubense ( FOC ) race 4 , the transcript patterns of WNB1 and WST3 was enhanced , which implied that the expression of WNB1 and WST3 may be related to the resistance of banana to Fusarium wilt .
| Matching Sentences: [ Sen. 4, subscore: 1.00 ]: The deduced amino acids of other four RGAs ( WST1 , WST2 , WST3 and WST4 ) all contain the serine/threonine kinase domain and WST3 encodes a polypeptide homologous to that of bacterial blight resistance gene Xa21 of rice .
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Score: 1.00 | Title: Proteome analysis of detergent-resistant membranes ( DRMs ) associated with OsRac1-mediated innate immunity in rice .
| Author: Fujiwara M Hamada S Hiratsuka M Fukao Y Kawasaki T Shimamoto K | Journal: Plant Cell Physiol Type: MEDLINE | Literature: oryza Field: abstract Doc ID: pub19502382 | Abstract: OsRac1 , a member of the Rac/Rop GTPase family , plays important roles as a molecular switch in rice innate immunity , and the active form of OsRac1 functions in the plasma membrane ( PM ) .
To study the precise localization of OsRac1 in the PM and its possible association with other signaling components , we performed proteomic analysis of DRMs ( detergent-resistant membranes ) isolated from rice suspension-cultured cells transformed with myc-tagged constitutively active ( CA ) OsRac1 .
DRMs are regions of the PM that are insoluble after Triton X-100 treatment under cold conditions and are thought to be involved in various signaling processes in animal , yeast and plant cells .
We identified 192 proteins in DRMs that included receptor-like kinases ( RLKs ) such as Xa21 , nucleotide-binding leucine-rich repeat ( NB-LRR ) -type disease resistance proteins , a glycosylphosphatidylinositol ( GPI ) -anchored protein , syntaxin , NADPH oxidase , a WD-40 repeat family protein and various GTP-binding proteins .
Many of these proteins have been previously identified in the DRMs isolated from other plant species , and animal and yeast cells , validating the methods used in our study .
To examine the possible association of DRMs and OsRac1-mediated innate immunity , we used rice suspension-cultured cells transformed with myc-tagged wild-type ( WT ) OsRac1 and found that OsRac1 and RACK1A , an effector of OsRac1 , shifted to the DRMs after chitin elicitor treatment .
These results suggest that OsRac1-mediated innate immunity is associated with DRMs in the PM .
| Matching Sentences: [ Sen. 4, subscore: 1.00 ]: We identified 192 proteins in DRMs that included receptor-like kinases ( RLKs ) such as Xa21 , nucleotide-binding leucine-rich repeat ( NB-LRR ) -type disease resistance proteins , a glycosylphosphatidylinositol ( GPI ) -anchored protein , syntaxin , NADPH oxidase , a WD-40 repeat family protein and various GTP-binding proteins .
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Score: 1.00 | Title: Secretion , modification , and regulation of Ax21 .
| Author: Han SW Lee SW Ronald PC | Journal: Curr Opin Microbiol Type: MEDLINE | Literature: oryza Field: abstract Doc ID: pub21236725 | Abstract: Innate immunity provides a first line of defense against pathogen attack and is activated rapidly following infection .
Although it is now widely appreciated that host receptors of conserved microbial signatures play a key role in innate immunity in plants and animals , very little is known about the biological function of the microbially derived molecules recognized by such receptors .
We have recently demonstrated that the rice XA21 receptor binds the AxY ( S ) 22 peptide corresponding to the N-terminal region of Ax21 , a type I-secreted protein that is highly conserved in all Xanthomonas species as well as in Xylella fastidiosa and the human pathogen , Stenotrophomonas maltophilia .
We hypothesize that post-translational modification of Ax21 is carried out by the RaxP , RaxQ , and RaxST proteins and that perception and regulation of Ax21 is controlled by the RaxR/H and PhoP/Q 2-component regulatory systems .
Ax21 is predicted to serve as an inducer of quorum sensing ( QS ) , a process where bacteria communicate with one another .
Because this is the first example of a conserved microbial signature that binds a host receptor and is also predicted to serve as an inducer of QS , this work has revealed fundamental new principles governing host-microbe interactions and has provided insight into the signaling dynamics of microbial communities .
| Matching Sentences: [ Sen. 3, subscore: 1.00 ]: We have recently demonstrated that the rice XA21 receptor binds the AxY ( S ) 22 peptide corresponding to the N-terminal region of Ax21 , a type I-secreted protein that is highly conserved in all Xanthomonas species as well as in Xylella fastidiosa and the human pathogen , Stenotrophomonas maltophilia .
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Score: 1.00 | Title: Comparative genomics reveals diversity among xanthomonads infecting tomato and pepper .
| Author: Potnis N Krasileva K Chow V Almeida NF Patil PB Ryan RP Sharlach M Behlau F Dow JM Momol M White FF Preston JF Vinatzer BA Koebnik R Setubal JC Norman DJ Staskawicz BJ Jones JB | Journal: BMC Genomics Type: MEDLINE | Literature: oryza Field: abstract Doc ID: pub21396108 | Abstract: BACKGROUND : Bacterial spot of tomato and pepper is caused by four Xanthomonas species and is a major plant disease in warm humid climates .
The four species are distinct from each other based on physiological and molecular characteristics .
The genome sequence of strain 85-10 , a member of one of the species , Xanthomonas euvesicatoria ( Xcv ) has been previously reported .
To determine the relationship of the four species at the genome level and to investigate the molecular basis of their virulence and differing host ranges , draft genomic sequences of members of the other three species were determined and compared to strain 85-10 .
RESULTS : We sequenced the genomes of X vesicatoria ( Xv ) strain 1111 ( ATCC 35937 ) , X perforans ( Xp ) strain 91-118 and X gardneri ( Xg ) strain 101 ( ATCC 19865 ) .
The genomes were compared with each other and with the previously sequenced Xcv strain 85-10 .
In addition , the molecular features were predicted that may be required for pathogenicity including the type III secretion apparatus , type III effectors , other secretion systems , quorum sensing systems , adhesins , extracellular polysaccharide , and lipopolysaccharide determinants .
Several novel type III effectors from Xg strain 101 and Xv strain 1111 genomes were computationally identified and their translocation was validated using a reporter gene assay .
A homolog to Ax21 , the elicitor of XA21-mediated resistance in rice , and a functional Ax21 sulfation system were identified in Xcv .
Genes encoding proteins with functions mediated by type II and type IV secretion systems have also been compared , including enzymes involved in cell wall deconstruction , as contributors to pathogenicity .
CONCLUSIONS : Comparative genomic analyses revealed considerable diversity among bacterial spot pathogens , providing new insights into differences and similarities that may explain the diverse nature of these strains .
Genes specific to pepper pathogens , such as the O-antigen of the lipopolysaccharide cluster , and genes unique to individual strains , such as novel type III effectors and bacteriocin genes , have been identified providing new clues for our understanding of pathogen virulence , aggressiveness , and host preference .
These analyses will aid in efforts towards breeding for broad and durable resistance in economically important tomato and pepper cultivars .
| Matching Sentences: [ Sen. 9, subscore: 1.00 ]: A homolog to Ax21 , the elicitor of XA21-mediated resistance in rice , and a functional Ax21 sulfation system were identified in Xcv .
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Score: 1.00 | Title: Characteristic expression of rice pathogenesis-related proteins in rice leaves during interactions with Xanthomonas oryzae pv . oryzae .
| Author: Hou M Xu W Bai H Liu Y Li L Liu L Liu B Liu G | Journal: Plant Cell Rep Type: In-Process | Literature: oryza Field: abstract Doc ID: pub22187088 | Abstract: Pathogenesis-related ( PR ) proteins play an important role in the disease resistance response .
To better understand the function of rice PR proteins , we examined the expressions of ten PR proteins in rice leaves at different developmental stages with or without the interaction between rice and Xanthomonas oryzae pv . oryzae ( Xoo ) .
The results showed that most of the PR proteins were expressed in rice leaves in normal growth conditions , suggesting that they play a role in rice growth .
Six out of ten PR proteins ( PR1 , PR2 , PR3 , PR4b , PR8 , and PR-pha ) showed enhanced expression in Xa21-mediated resistance responses at late stages after inoculation with Xoo .
The remaining four PR proteins ( PR5 , PR6 , PR15 , and PR16 ) did not show changes in expression in the resistance response .
The expressions of PR proteins in the resistance reaction were further compared with those in the susceptible reaction and a mock treatment .
Interestingly , several of the PR proteins were expressed at the highest levels in the susceptible reaction and at the lowest levels in the mock treatment .
Among the other four PR proteins , PR5 and PR16 showed changes in the abundance only in the susceptible response , while PR6 and PR15 showed no detectable difference in expression .
These data provide fundamental knowledge about the expression of PR proteins in the interaction between rice and Xoo .
| Matching Sentences: [ Sen. 4, subscore: 1.00 ]: Six out of ten PR proteins ( PR1 , PR2 , PR3 , PR4b , PR8 , and PR-pha ) showed enhanced expression in Xa21-mediated resistance responses at late stages after inoculation with Xoo .
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Score: 1.00 | Title: Expression of Xa1 , a bacterial blight-resistance gene in rice , is induced by bacterial inoculation .
| Author: Yoshimura S Yamanouchi U Katayose Y Toki S Wang ZX Kono I Kurata N Yano M Iwata N Sasaki T | Journal: Proc . Natl . Acad . Sci . USA Type: ARTICLE | Literature: oryza Field: abstract Doc ID: pub9465073 | Abstract: The Xa1 gene in rice confers resistance to Japanese race 1 of Xanthomonas oryzae pv . oryzae , the causal pathogen of bacterial blight ( BB ) .
We isolated the Xa1 gene by a map-based cloning strategy .
The deduced amino acid sequence of the Xa1 gene product contains nucleotide binding sites ( NBS ) and a new type of leucine-rich repeats ( LRR ) ; thus , Xa1 is a member of the NBS-LRR class of plant disease-resistance genes , but quite different from Xa21 , another BB-resistance gene isolated from rice .
Interestingly , Xa1 gene expression was induced on inoculation with a bacterial pathogen and wound , unlike other isolated resistance genes in plants , which show constitutive expression .
The induced expression may be involved in enhancement of resistance against the pathogen . | Matching Sentences: [ Sen. 3, subscore: 1.00 ]: The deduced amino acid sequence of the Xa1 gene product contains nucleotide binding sites ( NBS ) and a new type of leucine-rich repeats ( LRR ) ; thus , Xa1 is a member of the NBS-LRR class of plant disease-resistance genes , but quite different from Xa21 , another BB-resistance gene isolated from rice .
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Score: 1.00 | Title: Short communication : developmental control of Xa21-mediated disease resistance in rice .
| Author: Century KS Lagman RA Adkisson M Morlan J Tobias R Schwartz K Smith A Love J Ronald PC Whalen MC .
| Journal: Plant J Type: ARTICLE | Literature: oryza Field: title Doc ID: pub10571882 | Abstract: The rice resistance gene Xa21 confers resistance against the bacterial pathogen Xanthomonas oryzae pv . oryzae ( Xoo ) .
The molecular genetic mechanism controlling the integration of the Xa21-mediated disease resistance response with the developmental program in rice is under study in this model system .
Reproducible means of infecting plants at certain developmental stages were designed based on the timing of full expansion of the leaf .
Xa21-resistance progressively increases from the susceptible juvenile leaf 2 stage through later stages , with 100% resistance at the adult leaf 9/10 stage .
We found that Xa21 expression is independent of plant developmental stage , infection with Xoo , or wounding .
Expression of the Xa21 gene transcript is not correlated with expression of Xa21 disease resistance indicating that the developmental regulation of Xa21-resistance is either controlled post-transcriptionally or by other factors . | Matching Sentences: [ Sen. 1, subscore: 1.00 ]: Short communication : developmental control of Xa21-mediated disease resistance in rice .
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Score: 1.00 | Title: [ Introduction of wide spectrum rice bacterial blight resistance gene Xa21 into two-line genic male sterile rice variety Peiai 64S ] | Author: Zhao B Wang WM Zheng XW Wang CL Ma BJ Xue QZ Zhu LH Zhai WX .
| Journal: Sheng Wu Gong Cheng Xue Bao Type: ARTICLE | Literature: oryza Field: title Doc ID: pub10976312 | Abstract: Agrobacterium-mediated transformation of two-line genic male sterile Indica rice variety Peiai 64S was conducted using a cloned gene , Xa21 , as the foreign gene and mature embryo calli as the recipients .
A total of 46 transgenic plants had been obtained .
The PCR analysis and Southern blotting showed the integration of Xa21 gene into the genome the transgenic plants .
Results of inoculation with philippine race 6 of Xanthomonas oryzae pv . oryzae indicated that most of transgenic plants obtained high resistance to rice bacterial blight disease ( Xoo ) .
Analyses of T1 plants of the tested transgenic lines showed that integrated Xa21 gene could be steadily inherited and segregated in a 3 : 1 ratio . | Matching Sentences: [ Sen. 1, subscore: 1.00 ]: [ Introduction of wide spectrum rice bacterial blight resistance gene Xa21 into two-line genic male sterile rice variety Peiai 64S ]
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Score: 1.00 | Title: Biochemical characterization of the kinase domain of the rice disease resistance receptor-like kinase XA21 .
| Author: Liu GZ Pi LY Walker JC Ronald PC Song WY .
| Journal: J Biol . Chem . Type: ARTICLE | Literature: oryza Field: title Doc ID: pub11927577 | Abstract: The rice disease resistance gene , Xa21 , encodes a receptor kinase-like protein consisting of leucine-rich repeats in the putative extracellular domain and a serine/threonine kinase in the putative intracellular domain .
The putative XA21 kinase domain was expressed as maltose-binding and glutathione S-transferase fusion proteins in Escherichia coli .
The fusion proteins are capable of autophosphorylation .
Phosphoamino acid analysis of the glutathione S-transferase fusion protein indicates that only serine and threonine residues are phosphorylated .
The relative phosphorylation rate of the XA21 kinase against increasing enzyme concentrations follows a first-order rather than second-order kinetics , indicating an intramolecular phosphorylation mechanism .
Moreover , the active XA21 kinase can not phosphorylate a kinase-deficient mutant of XA21 kinase .
The enzymatic activity of the XA21 kinase in a buffer containing Mn ( 2+ ) is at least 15 times higher than that with Mg ( 2+ ) .
The K ( m ) and V ( max ) of XA21 kinase for ATP are 0 . 3 microm and 8 . 4 nmol/mg/min , respectively .
Tryptic phosphopeptide mapping reveals that multiple sites on the XA21 kinase are phosphorylated .
Finally , our data suggest that the region of XA21 kinase corresponding to the RD kinase activation domain is not phosphorylated , revealing a distinct mode of action compared with the tomato Pto serine/threonine kinase conferring disease resistance . | Matching Sentences: [ Sen. 1, subscore: 1.00 ]: Biochemical characterization of the kinase domain of the rice disease resistance receptor-like kinase XA21 .
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Score: 1.00 | Title: [ Genetic mapping of T-DNA integration sites in Xa21 transgenic rice ] | Author: Zhu XF Chen XW Li XB Qian Q Huang DN Zhu LH Zhai WX .
| Journal: Yi Chuan Xue Bao Type: ARTICLE | Literature: oryza Field: title Doc ID: pub12561472 | Abstract: The transformation mediated by Agrobacterium has been successfully applied to rice in recent years .
In the previous research we have transferred the Xa21 gene into five rice varieties of China , using Agrobacterium-mediated trasformation .
In this study , T-DNA flanking sequences of Xa21 transgenic rice lines were obtained by using thermal asymmetric interlaced PCR ( TAIL-PCR ) .
The flanking sequences which are actual rice DNA were identified and located on molecular linkage map developed from a ZYQ8/JX17 double haploid ( DH ) population .
A total of 22 T-DNA flanking rice sequences were isolated .
Nineteen of them displayed RFLPs between the two parents , ZYQ8 and JX17 , and were mapped on the rice chromosomes , 3 , 4 , 7 , 9 , 10 , 11 and 12 , respectively .
The genetic mapping of T-DNA integration sites in Xa21 transgenic rice will benefit the study of position effect and stable inheritance of the transgene Xa21 . | Matching Sentences: [ Sen. 1, subscore: 1.00 ]: [ Genetic mapping of T-DNA integration sites in Xa21 transgenic rice ]
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Score: 1.00 | Title: Genetic and physical analysis of the rice bacterial blight disease resistance locus , Xa21 .
| Author: Ronald PC Albano B Tabien R Abenes L Wu KS McCouch S Tanksley SD .
| Journal: Mol . Gen . Genet . Type: ARTICLE | Literature: oryza Field: title Doc ID: pub1362973 | Abstract: Nearly isogenic lines ( NILs ) of rice ( Oryza sativa ) differing at a locus conferring resistance to the pathogen Xanthomonas oryzae pv . oryzae were surveyed with 123 DNA markers and 985 random primers using restriction fragment length plymorphism ( RFLP ) and random amplified polymorphic DNA ( RAPD ) analysis .
One chromosome 11 marker ( RG103 ) detected polymorphism between the NILs that cosegregated with Xa21 .
All other chromosome 11 DNA markers tested were monomorphic between the NILs , localizing the Xa21 introgressed region to an 8 . 3 cM interval on chromosome 11 .
Furthermore , we identified two polymerase chain reaction ( PCR ) products ( RAPD2148 and RAPD818 ) that detected polymorphisms between the NILs .
Genomic sequences hybridizing with RAPD818 , RAPD248 and RG103 were duplicated specifically in the Xa21 NIL .
All three markers cosegregated with the resistance locus , Xa21 , in a F2 population of 386 progeny .
Based on the frequency with which we recovered polymorphic Xa21-linked markers , we estimated the physical size of the introgressed region to be approximately 800 kb .
This estimation was supported by physical mapping ( using pulsed field gel electrophoresis ) of the sequences hybridizing with the three Xa21-linked DNA markers .
The results showed that the three Xa21-linked markers are physically close to each other , with one copy of the RAPD818 sequences located within 60 kb of RAPD248 and the other copy within 270 kb of RG103 .
None of the enzymes tested generated a DNA fragment that hybridized with all three of the markers indicating that the introgressed region containing the resistance locus Xa21 is probably larger than 270 kb . | Matching Sentences: [ Sen. 1, subscore: 1.00 ]: Genetic and physical analysis of the rice bacterial blight disease resistance locus , Xa21 .
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Score: 1.00 | Title: Isolation and characterization of rice mutants compromised in Xa21-mediated resistance to X oryzae pv . oryzae .
| Author: Wang GL Wu C Zeng L He C Baraoidan M de Assis Goes da Silva F Williams CE Ronald PC Leung H | Journal: Theor . Appl . Genet . Type: ARTICLE | Literature: oryza Field: title Doc ID: pub14523518 | Abstract: The rice gene , Xa21 , confers resistance to diverse races of Xanthomonas oryzae pv . oryzae ( Xoo ) and encodes a receptor-like kinase with leucine-rich repeats in the extra-cellular domain .
To identify genes essential for the function of the Xa21 gene , 4 , 500 IRBB21 ( Xa21 isogenic line in IR24 background ) mutants , induced by diepoxybutane and fast neutrons , were screened against Philippine race six ( PR6 ) Xoo for a change from resistance to susceptibility .
From two greenhouse screens , 23 mutants were identified that had changed from resistant to fully ( 6 ) or partially ( 17 ) susceptible to PR6 .
All fully susceptible mutants carried rearrangements at the Xa21 locus as detected by PCR and Southern hybridization .
For the partially susceptible mutants , no changes were detected at the Xa21 locus based on Southern and PCR analyses .
However , two of these mutants were confirmed via genetic analysis to have mutations at the Xa21 locus .
Partially susceptible mutants exhibited variation in level of susceptibility to different Xoo strains , suggesting that they may carry different mutations required for the Xa21-mediated resistance .
The mutants identified in this study provide useful materials for dissecting the Xa21-mediated resistance pathway in rice . | Matching Sentences: [ Sen. 1, subscore: 1.00 ]: Isolation and characterization of rice mutants compromised in Xa21-mediated resistance to X oryzae pv . oryzae .
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Score: 1.00 | Title: Bacterial genes involved in type I secretion and sulfation are required to elicit the rice Xa21-mediated innate immune response .
| Author: da Silva FG Shen Y Dardick C Burdman S Yadav RC de Leon AL Ronald PC .
| Journal: Mol .
Plant Microbe Interact .
Type: ARTICLE | Literature: oryza Field: title Doc ID: pub15195942 | Abstract: Innate immunity to microorganisms relies on the specific sensing of pathogen-associated molecules by host recognition receptors .
Whereas studies in animals have largely focused on the recognition of extracellular pathogen-associated molecules by the TLR ( toll-like receptor ) superfamily , few studies have been carried out in plants , and it is not understood how these molecules are secreted or modified .
The rice Xa21 gene encodes a receptor-like kinase that provides immunity against strains of the bacterial pathogen Xanthomonas oryzae pv . oryzae carrying AvrXa21 activity .
We identified four X oryzae pv . oryzae genes that are required for AvrXa21 activity . raxA , raxB , and raxC encode proteins with similarity to a membrane fusion protein , an ATP-binding cassette transporter , and an outer membrane protein , respectively , of bacterial type I secretion systems .
The fourth gene , raxST , encodes a sulfotransferase-like protein .
Sequence analysis of three naturally occurring X oryzae pv . oryzae strains no longer recognized by Xa21 revealed alterations in the raxST and raxA genes .
The raxC gene complemented an Escherichia coli tolC mutant for secretion of a double glycine-leader peptide confirming the function of raxC in type I secretion .
These results indicate that bacterial type I secretion is necessary for Xa21-mediated recognition and immunity and further suggest that type I secretion and modification of pathogen-associated molecules play an important role in triggering the innate immune response in rice . | Matching Sentences: [ Sen. 1, subscore: 1.00 ]: Bacterial genes involved in type I secretion and sulfation are required to elicit the rice Xa21-mediated innate immune response .
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Score: 1.00 | Title: [ Study on the teratogenicity effects of genetically modified rice with Xa21 on rats ] | Author: Li Y Piao J Zhuo Q Chen X Mao D Yang L Yang X | Journal: Type: ARTICLE | Literature: oryza Field: title Doc ID: pub15727184 | Abstract: OBJECTIVE : To observe the effects of genetically modified rice with Xa21 on the development of rat embryos .
METHODS : According to sex , weanling rats were divided into four groups : transgenic rice group , non-transgenic rice group , AIN93G negative control group and MATDA positive control group .
The rats were fed with corresponding food for 90 days and mated .
The development of maternal rats and embryos were observed .
RESULTS : The body weight gain of pregnant rats and the body weight , body length and tail length of fetal rats in transgenic rice group were significant increased than those in positive control group .
The number of death embryos and adsorption embryos , the malformation rate ( appearance , viscera , skeleton ) in transgenic rice group were lower than those in positive control group .
There were no significant difference of all indicators among transgenic rice group , non-transgenic rice group and AIN93G negative control group .
CONCLUSION : Compared with the non-transgenic rice , transgenic rice modified with Xa21 gene showed no significant differences in rat pregnant rate and embryo development . | Matching Sentences: [ Sen. 1, subscore: 1.00 ]: [ Study on the teratogenicity effects of genetically modified rice with Xa21 on rats ]
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Score: 1.00 | Title: [ Isolation and Sequence Analysis of the Xa21 Gene Wxon II Homologus from Different Species of Wild Rice in Yunnan . ] | Author: Qian J Cheng ZQ Yang MZ Liu JM Wu CJ Huang XQ .
| Journal: Yi Chuan Type: ARTICLE | Literature: oryza Field: title Doc ID: pub15985401 | Abstract: The Xa21 gene previously cloned from the wild rice species Oryzae longistaminata confers broad-spectrum resistance to rice leaf blight caused by different strains of Xanthomonas oryzae pv . oryzae .
Here we attempted to determine the existence of Xa21 homologs in other wild rice species and rice cultivars and the sequence differences between the homologs .
We synthesized specific primers based on the reported Xa21 sequence to amplify homologs of the gene exon II from several rice cultivars and three wild rice species in Yunnan Province , China .
The fragments cloned from various types of O rufipogon Griff from Jinghong and Yuanjiang , Yunnan Province , were highly homologous to the reported Xa21 gene exon II .
However , the fragment was not found in O officinalis Wall . and O meyeriana Baill .
Sequence analysis suggested that differences in nucleotides were located randomly in the fragments we cloned .
| Matching Sentences: [ Sen. 1, subscore: 1.00 ]: [ Isolation and Sequence Analysis of the Xa21 Gene Wxon II Homologus from Different Species of Wild Rice in Yunnan . ]
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Score: 1.00 | Title: The autophosphorylated Ser686 , Thr688 , and Ser689 residues in the intracellular juxtamembrane domain of XA21 are implicated in stability control of rice receptor-like kinase .
| Author: Xu WH Wang YS Liu GZ Chen X Tinjuangjun P Pi LY Song WY .
| Journal: Plant J Type: ARTICLE | Literature: oryza Field: title Doc ID: pub16460508 | Abstract: The rice gene Xa21 confers resistance against Xanthomonas oryzae pv . oryzae ( Xoo ) .
Xa21 encodes a receptor-like kinase ( XA21 ) .
We demonstrate that XA21 autophosphorylates residues Ser686 , Thr688 and Ser689 in vitro .
Substitution of these residues with alanines did not affect the autophosphorylation function of this kinase , but specifically destabilized the resistance protein in vitro and in vivo .
Plants carrying these same substitutions in XA21 were compromised in their resistance to the normally avirulent Xoo Philippine race 6 .
Additionally , we show that wild-type XA21 and the kinase-dead mutant with the invariable Lys736 residue mutated to glutamic acid were also proteolytically degraded in protein extracts .
Finally , we show a correlation between the in vitro degradation and in vivo instability of the proteins .
We propose that autophosphorylation of Ser686 , Thr688 and Ser689 functions to stabilize XA21 against the developmentally controlled proteolytic activity . | Matching Sentences: [ Sen. 1, subscore: 1.00 ]: The autophosphorylated Ser686 , Thr688 , and Ser689 residues in the intracellular juxtamembrane domain of XA21 are implicated in stability control of rice receptor-like kinase .
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Score: 1.00 | Title: [ Generation of selectable marker-free and vector backbone sequence-free Xa21 transgenic rice ] | Author: Xia ZH Li XB Chen CY Fan HK Jiang GH Zhu LH Zhai WX .
| Journal: Sheng Wu Gong Cheng Xue Bao Type: ARTICLE | Literature: oryza Field: title Doc ID: pub16607944 | Abstract: The dominant gene Xa21 with broad-spectrum and high resistance to Xanthomonas oryzae pv . oryzae ( Xoo ) was transferred into C418 , an important restorer line of japonica hybrid rice in China using double right-border ( DRB ) T-DNA binary vector through Agrobacterium-mediated transformation .
17 transgenic lines were Xa21-positive with high resistance to the race P6 of Xoo through PCR analysis and resistance identification , among the total 27 independent primary transformants ( T0 ) obtained .
The subsequent analysis of the T1 progenies of these 17 T0 lines through PCR-assisted selection and resistance investigation showed that four Xa21 transgenic T0 lines could produce selectable marker-free ( SMF ) progenies .
The frequency of primary transformants producing SMF progenies was 15% .
In addition , PCR analysis also revealed these SMF progenies did not contain vector backbone sequence , and they were named as SMF and vector backbone sequence-free ( SMF-VBSF ) Xa21 transgenic plants .
The further molecular and phenotypic analysis of the T2 and T3 progenies testified the homozygous SMF-VBSF Xa21 transgenic plants were obtained with high resistance to Xoo .
| Matching Sentences: [ Sen. 1, subscore: 1.00 ]: [ Generation of selectable marker-free and vector backbone sequence-free Xa21 transgenic rice ]
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Score: 1.00 | Title: [ Advances of rice bacterial blight disease resistance gene Xa21 ] | Author: Bai H Li LY Liu GZ .
| Journal: Yi Chuan Type: ARTICLE | Literature: oryza Field: title Doc ID: pub16818441 | Abstract: Gene Xa21 is the first disease resistance gene cloned from rice ( Oryza sativa L ) , which encodes a receptor-like kinase and confers broad spectrum resistance against Xanthomonas oryzae pv . oryzae ( Xoo ) .
In this paper , the discovery , mapping and cloning of Xa21 were reviewed briefly .
The molecular mechanism of resistance and its breeding application , including biochemical properties of the kinase domain of XA21 , AvrXa21 identification , the disease resistance pathway mediated by Xa21 , and the mechanism of disease resistance were summarized .
Future perspective on Xa21-related research is also discussed . | Matching Sentences: [ Sen. 1, subscore: 1.00 ]: [ Advances of rice bacterial blight disease resistance gene Xa21 ]
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Score: 1.00 | Title: [ Expression and autophosphorylation analysis of XA21 and PI-D2 protein kinases in Saccharomyces cerevisiae ] | Author: Wang SL Li LY Shang JJ Wang J Liu GZ | Journal: Wei Sheng Wu Xue Bao Type: In-Process | Literature: oryza Field: title Doc ID: pub18271255 | Abstract: Rice bacterial blight and blast are the most crucial rice disease .
Xa21 confers resistance to bacterial blight , while Pi-d2 confers resistance to rice blast Both Xa21 and Pi-d2 encode receptor kinase-like proteins .
Biochemical properties of XA21 kinase expressed in bacterial were characterized in our previous report .
In this study , both XA21 and PI-D2 kinase domain were PCR amplified and cloned into yeast expression vector pEGH via recombinational cloning strategy , kinase proteins expressed in eukaryotic yeast system was purified and autophosphorylation assay was carried out .
The results indicated that XA21 and PI-D2 protein can be detected by SDS-PAGE and showed expected molecular weight .
Autophosphorylation assay indicated that yeast expressed XA21 and PI-D2 were active when incubated with P32 labelled ATP .
The experiment provided basic materials for biochemical prosperity analysis , protein-protein interaction and substrate screening research .
| Matching Sentences: [ Sen. 1, subscore: 1.00 ]: [ Expression and autophosphorylation analysis of XA21 and PI-D2 protein kinases in Saccharomyces cerevisiae ]
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Score: 1.00 | Title: Rice XB15 , a protein phosphatase 2C , negatively regulates cell death and XA21-mediated innate immunity .
| Author: Park CJ Peng Y Chen X Dardick C Ruan D Bart R Canlas PE Ronald PC | Journal: PLoS Biol Type: MEDLINE | Literature: oryza Field: title Doc ID: pub18817453 | Abstract: Perception of extracellular signals by cell surface receptors is of central importance to eukaryotic development and immunity .
Kinases that are associated with the receptors or are part of the receptors themselves modulate signaling through phosphorylation events .
The rice ( Oryza sativa L ) XA21 receptor kinase is a key recognition and signaling determinant in the innate immune response .
A yeast two-hybrid screen using the intracellular portion of XA21 , including the juxtamembrane ( JM ) and kinase domain as bait , identified a protein phosphatase 2C ( PP2C ) , called XA21 binding protein 15 ( XB15 ) .
The interaction of XA21 and XB15 was confirmed in vitro and in vivo by glutathione-S-transferase ( GST ) pull-down and co-immunoprecipitation assays , respectively .
XB15 fusion proteins purified from Escherichia coli and from transgenic rice carry PP2C activity .
Autophosphorylated XA21 can be dephosphorylated by XB15 in a temporal and dosage-dependent manner .
A serine residue in the XA21 JM domain is required for XB15 binding .
Xb15 mutants display a severe cell death phenotype , induction of pathogenesis-related genes , and enhanced XA21-mediated resistance .
Overexpression of Xb15 in an XA21 rice line compromises resistance to the bacterial pathogen Xanthomonas oryzae pv . oryzae .
These results demonstrate that Xb15 encodes a PP2C that negatively regulates the XA21-mediated innate immune response .
| Matching Sentences: [ Sen. 1, subscore: 1.00 ]: Rice XB15 , a protein phosphatase 2C , negatively regulates cell death and XA21-mediated innate immunity .
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Score: 1.00 | Title: [ Application of competitive PCR for screening selectable marker-free Xa21 transgenic rice ] | Author: Xia Z Gao L Luo Y Deng X Li S Zhai W | Journal: Sheng Wu Gong Cheng Xue Bao Type: In-Process | Literature: oryza Field: title Doc ID: pub19637639 | Abstract: Polymerase chain reaction ( PCR ) is a simple , quick and highly sensitive method .
However the accuracy of the conventional PCR assay was often affected by false positives and false negatives .
In this study , a protocol competitive PCR was used to reduce the false results in screening for selectable marker-free ( SMF ) Xa2l transgenic rice plants .
The competitive template of Xa21 was the endogenous Xa2l homologous sequence located on chromosome 11 .
The competitive template of the selectable marker gene , hygromycin phosphotransferase ( hpt ) , was an additive DNA extracted from hpt transgenic Nipponbare ( Oryza sativa L ) .
Through competitive PCR analysis of transgenic T1 plants produced by double right border binary vector , false positive or false negative samples were effectively diminished , and genuine SMF Xa21 transgenic plants were obviously obtained .
Comparing with the conventional non-competitive PCR , competitive PCR increased the accuracy for selecting SMF Xa21 transgenic plants .
The results of bacterial blight ( BB ) resistance tests and hygromycin B resistance assay of SMF Xa21 transgenic plants testified the reliability of this method .
| Matching Sentences: [ Sen. 1, subscore: 1.00 ]: [ Application of competitive PCR for screening selectable marker-free Xa21 transgenic rice ]
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Score: 1.00 | Title: A type I-secreted , sulfated peptide triggers XA21-mediated innate immunity .
| Author: Lee SW Han SW Sririyanum M Park CJ Seo YS Ronald PC | Journal: Science Type: MEDLINE | Literature: oryza Field: title Doc ID: pub19892983 | Abstract: The rice Xa21 gene confers immunity to most strains of the bacterium Xanthomonas oryzae pv . oryzae ( Xoo ) .
Liquid chromatography-tandem mass spectrometry analysis of biologically active fractions from Xoo supernatants led to the identification of a 194-amino acid protein designated Ax21 ( activator of XA21-mediated immunity ) .
A sulfated , 17-amino acid synthetic peptide ( axY ( S ) 22 ) derived from the N-terminal region of Ax21 is sufficient for activity , whereas peptides lacking tyrosine sulfation are biologically inactive .
Using coimmunoprecipitation , we found that XA21 is required for axY ( S ) 22 binding and recognition . axY ( S ) 22 is 100% conserved in all analyzed Xanthomonas species , confirming that Ax21 is a pathogen-associated molecular pattern and that XA21 is a pattern recognition receptor .
| Matching Sentences: [ Sen. 1, subscore: 1.00 ]: A type I-secreted , sulfated peptide triggers XA21-mediated innate immunity .
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Score: 1.00 | Title: Overexpression of the endoplasmic reticulum chaperone BiP3 regulates XA21-mediated innate immunity in rice .
| Author: Park CJ Bart R Chern M Canlas PE Bai W Ronald PC | Journal: PLoS One Type: MEDLINE | Literature: oryza Field: title Doc ID: pub20174657 | Abstract: Recognition of pathogen-associated molecular patterns by pattern recognition receptors ( PRRs ) activates the innate immune response .
Although PRR-mediated signaling events are critical to the survival of plants and animals , secretion and localization of PRRs have not yet been clearly elucidated .
Here we report the in vivo interaction of the endoplasmic reticulum ( ER ) chaperone BiP3 with the rice XA21 PRR , which confers resistance to the Gram negative bacterium , Xanthomonas oryzae pv . oryzae ( Xoo ) .
We show that XA21 is glycosylated and is primarily localized to the ER and also to the plasma membrane ( PM ) .
In BiP3-overexpressing rice plants , XA21-mediated immunity is compromised , XA21 stability is significantly decreased , and XA21 proteolytic cleavage is inhibited .
BiP3 overexpression does not affect the general rice defense response , cell death or brassinolide-induced responses .
These results indicate that BiP3 regulates XA21 protein stability and processing and that this regulation is critical for resistance to Xoo .
| Matching Sentences: [ Sen. 1, subscore: 1.00 ]: Overexpression of the endoplasmic reticulum chaperone BiP3 regulates XA21-mediated innate immunity in rice .
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Score: 1.00 | Title: Elucidation of XA21-mediated innate immunity .
| Author: Park CJ Han SW Chen X Ronald PC | Journal: Cell Microbiol Type: MEDLINE | Literature: oryza Field: title Doc ID: pub20590657 | Abstract: In the early 1970s , the Xa21 gene from the wild rice species Oryza longistaminata drew attention of rice breeders because of its broad-spectrum resistance to diverse strains of a serious bacterial disease of rice in Asia and Africa , called bacterial blight disease , caused by the Gram-negative bacterium , Xanthomonas oryzae pv . oryzae ( Xoo ) .
In 1995 , we isolated the gene controlling this resistance and in 2009 demonstrated that XA21 recognizes a highly conserved peptide , called Ax21 ( activator of XA21-mediated immunity ) .
Tyrosine sulfation of Ax21 is required for recognition by rice XA21 .
A decade of genetic , molecular and biochemical studies have uncovered key components of the XA21-mediated signalling cascade .
Ax21 recognition by XA21 at the cell surface induces phosphorylation-mediated events , which are predicted to alter subcellular localization and/or DNA-binding activity of a WRKY family of transcription factors .
Because XA21 is representative of the large number of predicted pattern recognition receptors ( PRRs ) in rice ( n = 328 ) , Arabidopsis ( n = 35 ) and other plant species , further characterization of XA21-mediated signalling pathways will contribute to elucidation of these important defence responses .
| Matching Sentences: [ Sen. 1, subscore: 1.00 ]: Elucidation of XA21-mediated innate immunity .
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Score: 1.00 | Title: Plasma membrane localization and potential endocytosis of constitutively expressed XA21 proteins in transgenic rice .
| Author: Chen F Gao MJ Miao YS Yuan YX Wang MY Li Q Mao BZ Jiang LW He ZH | Journal: Mol Plant Type: MEDLINE | Literature: oryza Field: title Doc ID: pub20616165 | Abstract: The rice pattern recognition receptor ( PRR ) XA21 confers race-specific resistance in leaf infection by bacterial blight Xathomonas oryzae pv . oryzae ( Xoo ) , and was shown to be primarily localized to the endoplasmic reticulum ( ER ) when expressed with its native promoter or overexpressed in the protoplast However , whether the protein is still ER-localization in the intact cell when overexpressed remains to be identified .
Here , we showed that XA21 , its kinase-dead mutant XA21P ( K736EP ) , and the triple autophosphorylation mutant XA21P ( S686A/T688A/S699A ) GFP fusions were primarily localized to the plasma membrane ( PM ) when overexpressed in the intact transgenic rice cell , and also localized to the ER in the transgenic protoplast The transgenic plants constitutively expressing the wild-type XA21 or its GFP fusion displayed race-specific resistance to Xoo at the adult and seedling stages .
XA21 and XA21P ( K736EP ) could be internalized probably via the SCAMP-positive early endosomal compartment in the protoplast , suggesting that XA21 might be endocytosed to initiate resistance responses during pathogen infection .
We also established a root infection system and demonstrated that XA21 also mediated race-specific resistance responses to Xoo in the root .
Our current study provides an insight into the nature of the XA21-mediated resistance and a practical approach using the root cell system to further dissect the cellular signaling of the PRR during the rice-Xoo interaction .
| Matching Sentences: [ Sen. 1, subscore: 1.00 ]: Plasma membrane localization and potential endocytosis of constitutively expressed XA21 proteins in transgenic rice .
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Score: 1.00 | Title: Ectopic expression of rice Xa21 overcomes developmentally controlled resistance to Xanthomonas oryzae pv . oryzae .
| Author: Park CJ Lee SW Chern M Sharma R Canlas PE Song MY Jeon JS Ronald PC | Journal: Plant Sci Type: In-Data-Review | Literature: oryza Field: title Doc ID: pub21076626 | Abstract: Recognition of pathogen-associated molecular patterns ( PAMPs ) by pattern recognition receptors ( PRRs ) activates the innate immune response .
The rice PRR , XA21 , confers robust resistance at adult stages to most strains of the bacterial pathogen Xanthomonas oryzae pv . oryzae ( Xoo ) .
Seedlings are still easily infected by Xoo , causing severe yield losses .
Here we report that Xa21 is induced by Xoo infection and that ectopic expression of Xa21 confers resistance at three leaf stage ( three-week-old ) , overcoming the developmental limitation of XA21-mediated resistance .
Ectopic expression of Xa21 also up-regulates a larger set of defense-related genes as compared to Xa21 driven by the native promoter .
These results indicate that altered regulation of Xa21 expression is useful for developing enhanced resistance to Xoo at multiple developmental stages .
| Matching Sentences: [ Sen. 1, subscore: 1.00 ]: Ectopic expression of rice Xa21 overcomes developmentally controlled resistance to Xanthomonas oryzae pv . oryzae .
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Score: 1.00 | Title: Transcriptional characteristics of Xa21-mediated defense responses in rice .
| Author: Gan Q Bai H Zhao X Tao Y Zeng H Han Y Song W Zhu L Liu G | Journal: J Integr Plant Biol Type: MEDLINE | Literature: oryza Field: title Doc ID: pub21324061 | Abstract: Bacterial blight , caused by Xanthomonas oryzae pv . oryzae ( Xoo ) , is the most destructive bacterial disease of rice .
The cloned rice gene Xa21 confers resistance to a broad spectrum of Xoo races .
To identify genes involved in Xa21-mediated immunity , a whole-genome oligonucleotide microarray of rice was used to profile the expression of rice genes between incompatible interactions and mock treatments at 0 , 4 , 8 , 24 , 72 and 120 h post inoculation ( hpi ) or between incompatible and compatible interactions at 4 hpi , respectively .
A total of 441 differentially expressed genes , designated as XDGs ( Xa21 mediated differentially expressed genes ) , were identified .
Based on their functional annotations , the XDGs were assigned to 14 categories , including defense-related , signaling , transcriptional regulators .
Most of the defense-related genes belonged to the pathogenesis-related gene family , which was induced dramatically at 72 and 120 hpi .
Interestingly , most signaling and transcriptional regulator genes were downregulated at 4 and 8 hpi , suggesting that negative regulation of cellular signaling may play a role in the Xa21-mediated defense response .
Comparison of expression profiles between Xa21 and other R gene-mediated defense systems revealed interesting common responses .
Representative XDGs with supporting evidences were also discussed .
| Matching Sentences: [ Sen. 1, subscore: 1.00 ]: Transcriptional characteristics of Xa21-mediated defense responses in rice .
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Score: 1.00 | Title: Adaptive evolution of Xa21 homologs in Gramineae .
| Author: Tan S Wang D Ding J Tian D Zhang X Yang S | Journal: Genetica Type: In-Process | Literature: oryza Field: title Doc ID: pub22451352 | Abstract: The XA21 protein has broad spectrum resistance against Xanthomonas oryzae pv . oryzae .
Although Xa21-mediated immunity is well characterized , little is known about the origin and evolutionary history of this gene in grasses .
Therefore , we analyzed all Xa21 gene homologs in eight whole-genome sequenced rice lines , as well as in four gramineous genomes , rice , Brachypodium , sorghum and maize ; using Arabidopsis Xa21 homologs as outgroups , 17 , 7 , 7 and 3 Xa21 homologs were detected in these four grasses , respectively .
Synteny and phylogenetic analysis showed that frequent gene translocation , duplication and/or loss , have occurred at Xa21 homologous loci , suggesting that they have undergone or are undergoing rapid generation of copy number variations .
Within the rice species , the high level of nucleotide diversity between Xa21-like orthologs showed a strong association with the presence/absence haplotypes , suggesting that the genetic structure of rice lines plays an important role in the variations between these Xa21-like orthologs .
Strongly positive selection was detected in the core region of the leucine-rich repeat domains of the Xa21 subclade among the rice lines , indicating that the rapid gene diversification of Xa21 homologs may be a strategy for a given species to adapt to the changing spectrum of species-specific pathogens .
| Matching Sentences: [ Sen. 1, subscore: 1.00 ]: Adaptive evolution of Xa21 homologs in Gramineae .
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Score: 1.00 | Title: Identification and expression analysis of components involved in rice Xa21-mediated disease resistance signalling .
| Author: Bai H Lan JP Gan Q Wang XY Hou MM Cao YH Li LY Liu LJ Hao YJ Yin CC Wu L Zhu LH Liu GZ | Journal: Plant Biol ( Stuttg ) Type: Publisher | Literature: oryza Field: title Doc ID: pub22672582 | Abstract: Rice Xa21 gene encodes a receptor-like kinase that confers broad-spectrum resistance against Xanthomonas oryzae pv . oryzae ( Xoo ) .
Recently , a number of genes involved in the Xa21-mediated disease resistance pathway have been identified .
Based on our previous data and the literature , we chose 16 candidate proteins and made corresponding antibodies .
Using Western blotting , we systematically investigated the expression profile of the proteins in Xa21-mediated disease resistance response .
We found nine proteins with altered expression .
We further compared their expression in resistance , susceptible and mock responses , and found that GST expression was up-regulated during the resistance process , indicating GST is a positive regulator in resistance responses .
ATPsB expression was down-regulated during both the resistance and susceptible response processes , although it was higher in the resistance response than that in the susceptible response .
The total amount of MYB , GAPDH , CatB , Trx and NB-ARC proteins was lower in the resistance than in the susceptible response , but their abundance per unit bacteria in the resistance response was still higher than in the susceptible response , suggesting that these proteins might be positive regulators in the resistance response .
In addition , expression of another ERF was induced by inoculation with bacterial blight pathogen , and expression of Zf-LSD1 was activated by wounding stress alone .
Interestingly , most proteins showed similar altered expression patterns in the resistance and susceptible responses , but differed to some extents , implying that both responses might share common molecular mechanisms .
This study revealed evidence of resistance-related protein expression , providing a foundation for better understanding of their functions .
| Matching Sentences: [ Sen. 1, subscore: 1.00 ]: Identification and expression analysis of components involved in rice Xa21-mediated disease resistance signalling .
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Score: 1.00 | Title: Cleavage and nuclear localization of the rice XA21 immune receptor .
| Author: Park CJ Ronald PC | Journal: Nat Commun Type: In-Data-Review | Literature: oryza Field: title Doc ID: pub22735448 | Abstract: Plants and animals carry specific receptors that recognize invading pathogens and respond by activating an immune response .
The rice XA21 receptor confers broad-spectrum immunity to the Gram-negative bacterial pathogen , Xanthomonas oryzae pv . oryzae upon recognition of a small protein , Ax21 , that is conserved in all Xanthomonas species and related genera .
Here we demonstrate that XA21 is cleaved to release the intracellular kinase domain and that this intracellular domain carries a functional nuclear localization sequence .
Bimolecular fluorescence complementation assays indicate that the XA21 intracellular domain interacts with the OsWRKY62 transcriptional regulator exclusively in the nucleus of rice protoplasts .
In vivo cleavage of XA21 and translocalization of the intracellular kinase domain to the nucleus is required for the XA21-mediated immune response .
These results suggest a new model for immune receptor function : on receptor recognition of conserved microbial signatures , the associated kinase translocates to the nucleus where it directly interacts with transcriptional regulators .
| Matching Sentences: [ Sen. 1, subscore: 1.00 ]: Cleavage and nuclear localization of the rice XA21 immune receptor .
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Score: 1.00 | Title: A receptor kinase-like protein encoded by the rice disease resistance gene , Xa21 .
| Author: Song WY Wang GL Chen LL Kim HS Pi LY Holsten T Gardner J Wang B Zhai WX Zhu LH Fauquet C Ronald P | Journal: Science Type: ARTICLE | Literature: oryza Field: title Doc ID: pub8525370 | Abstract: The rice Xa21 gene , which confers resistance to Xanthomonas oryzae pv . oryzae race 6 , was isolated by positional cloning .
Fifty transgenic rice plants carrying the cloned Xa21 gene display high levels of resistance to the pathogen .
The sequence of the predicted protein , which carries both a leucine-rich repeat motif and a serine-threonine kinase-like domain , suggests a role in cell surface recognition of a pathogen ligand and subsequent activation of an intracellular defense response .
Characterization of Xa21 should facilitate understanding of plant disease resistance and lead to engineered resistance in rice . | Matching Sentences: [ Sen. 1, subscore: 1.00 ]: A receptor kinase-like protein encoded by the rice disease resistance gene , Xa21 .
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Score: 1.00 | Title: The cloned gene , Xa21 , confers resistance to multiple Xanthomonas oryzae pv . oryzae isolates in transgenic plants .
| Author: Wang GL Song WY Ruan DL Sideris S Ronald PC .
| Journal: Mol .
Plant Microbe Interact .
Type: ARTICLE | Literature: oryza Field: title Doc ID: pub8969533 | Abstract: The cloned rice gene , Xa21 , confers resistance to multiple pathogen isolates of Xanthomonas oryzae pv . oryzae in transgenic plants .
The resistance phenotype was stably transmitted to T1 progeny and inherited as a single locus .
The T1 progeny were tested for resistance to 32 X oryzae pv . oryzae isolates from eight countries .
Both the engineered line and the donor line showed resistance to 29 isolates and susceptibility to three isolates .
The identical resistance spectrum of both lines indicates that the presence of a single member of a multigene family , Xa21 , is sufficient to confer multi-isolate resistance .
The results presented here have important implications for engineering disease resistance in crop plants . | Matching Sentences: [ Sen. 1, subscore: 1.00 ]: The cloned gene , Xa21 , confers resistance to multiple Xanthomonas oryzae pv . oryzae isolates in transgenic plants .
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Score: 1.00 | Title: Evolution of the rice Xa21 disease resistance gene family .
| Author: Song WY Pi LY Wang GL Gardner J Holsten T Ronald PC .
| Journal: Plant Cell Type: ARTICLE | Literature: oryza Field: title Doc ID: pub9286106 | Abstract: The rice disease resistance gene Xa21 , encoding a receptor-like kinase , is a member of a multigene family .
Sequence analysis of seven family members revealed two distinct classes of genes .
One member from each class encodes a receptor kinase-like open reading frame .
The other five members encode truncated open reading frames of the predicted receptor kinase .
A highly conserved 233-bp sequence ( HC ) was also identified among the seven family members .
Recombination at the HC region between family members apparently resulted in the precise swapping of promoter regions .
Large sequence duplications were generated by a presumed unequal crossover event in intergenic regions .
Insertions of transposon-like sequences truncated two of the predicted open reading frames .
A model for amplification and diversification of the Xa21 gene family is presented . | Matching Sentences: [ Sen. 1, subscore: 1.00 ]: Evolution of the rice Xa21 disease resistance gene family .
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Score: 1.00 | Title: Xa21D encodes a receptor-like molecule with a leucine-rich repeat domain that determines race-specific recognition and is subject to adaptive evolution .
| Author: Wang GL Ruan DL Song WY Sideris S Chen L Pi LY Zhang S Zhang Z Fauquet C Gaut BS Whalen MC Ronald PC .
| Journal: Plant Cell Type: ARTICLE | Literature: oryza Field: title Doc ID: pub9596635 | Abstract: The rice Xa21 gene confers resistance to Xanthomonas oryzae pv oryzae in a race-specific manner .
Analysis of the inheritance patterns and resistance spectra of transgenic plants carrying six Xa21 gene family members indicated that one member , designated Xa21D , displayed a resistance spectrum identical to that observed for Xa21 but conferred only partial resistance .
Xa21D encodes a receptor-like protein carrying leucine-rich repeat ( LRR ) motifs in the presumed extracellular domain .
The Xa21D transcript terminates shortly after the stop codon introduced by the retrotransposon Retrofit .
Comparison of nucleotide substitutions in the LRR coding regions of Xa21 and Xa21D provided evidence of adaptive selection .
Both functional and evolutionary evidence indicates that the Xa21D LRR domain controls race-specific pathogen recognition . | Matching Sentences: [ Sen. 1, subscore: 1.00 ]: Xa21D encodes a receptor-like molecule with a leucine-rich repeat domain that determines race-specific recognition and is subject to adaptive evolution .
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Score: 1.00 | Title: Identification and characterization of 14 transposon-like elements in the noncoding regions of members of the Xa21 family of disease resistance genes in rice .
| Author: Song WY Pi LY Bureau TE Ronald PC .
| Journal: Mol . Gen . Genet . Type: ARTICLE | Literature: oryza Field: title Doc ID: pub9669326 | Abstract: The rice disease resistance gene Xa21 , which encodes a receptor-like kinase , is a member of a multigene family .
Based on comparisons of genomic sequences of seven family members , seventeen transposon-like elements were identified in the 5 and 3 flanking regions and introns of these genes .
Sequence characterization revealed that these elements are diverse , showing similarity to maize Ds , CACTA and miniature inverted repeat-like elements , as well as novel elements .
Only two elements were located in presumed coding regions , indicating that integration of transposable elements at the Xa21 disease resistance locus occurred preferentially in noncoding regions . | Matching Sentences: [ Sen. 1, subscore: 1.00 ]: Identification and characterization of 14 transposon-like elements in the noncoding regions of members of the Xa21 family of disease resistance genes in rice .
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