|
Score: 23.00 |
|---|
| Title: Pathogen-induced expressional loss of function is the key factor in race-specific bacterial resistance conferred by a recessive R gene xa13 in rice .
| | Author: Yuan M Chu Z Li X Xu C Wang S | | Journal: Plant Cell Physiol Citation: V : 50 P : 947-55 Type: MEDLINE | | Literature: oryza Field: abstract Doc ID: pub19318375 Accession (PMID): 19318375 | | Abstract: The fully recessive disease resistance ( R ) gene xa13 , which mediates race-specific resistance to Xanthomonas oryzae pv . oryzae ( Xoo ) , encodes a plasma membrane protein that differs by one amino acid from that encoded by its dominant ( susceptible ) allele Xa13 .
The molecular mechanism of xa13-mediated resistance is largely unknown .
Here we show that , compared with its dominant allele , expressional non-reaction of xa13 to Xoo infection , not its protein composition , is the key factor for xa13-mediated resistance .
We used the promoter ( P ( Xa13 ) ) of the dominant Xa13 , which was induced by only the incompatible Xoo strain for xa13 , to regulate xa13 and xa13 ( Leu49 ) ( a natural recessive allele of xa13 ) in the rice line IRBB13 carrying xa13 .
The transgenic plants showed the same level of susceptibility and bacterial growth rate as those of the rice line carrying dominant Xa13 , accompanied by the induced accumulation of xa13 or xa13 ( Leu49 ) proteins .
Constitutive expression of dominant XA13 or different xa13 proteins ( xa13 , xa13 ( Leu49 ) , xa13 ( Ala85 ) or xa13 ( Val184 ) ) in IRBB13 had no effect on Xoo infection in the transgenic plants .
These results suggest that race-specific pathogen-induced Xa13 expression is critical for infection .
Thus , xa13 stands out from other R genes in that its functions in disease resistance are due to only the loss of pathogen-induced transcriptional motivation caused by natural selection .
| Matching Sentences:
[ Sen. 4, subscore: 7.00 ]: We used the promoter ( P ( Xa13 ) ) of the dominant Xa13 , which was induced by only the incompatible Xoo strain for xa13 , to regulate xa13 and xa13 ( Leu49 ) ( a natural recessive allele of xa13 ) in the rice line IRBB13 carrying xa13 .
[ Sen. 6, subscore: 6.00 ]: Constitutive expression of dominant XA13 or different xa13 proteins ( xa13 , xa13 ( Leu49 ) , xa13 ( Ala85 ) or xa13 ( Val184 ) ) in IRBB13 had no effect on Xoo infection in the transgenic plants .
[ Sen. 5, subscore: 3.00 ]: The transgenic plants showed the same level of susceptibility and bacterial growth rate as those of the rice line carrying dominant Xa13 , accompanied by the induced accumulation of xa13 or xa13 ( Leu49 ) proteins .
[ Sen. 1, subscore: 2.00 ]: The fully recessive disease resistance ( R ) gene xa13 , which mediates race-specific resistance to Xanthomonas oryzae pv . oryzae ( Xoo ) , encodes a plasma membrane protein that differs by one amino acid from that encoded by its dominant ( susceptible ) allele Xa13 .
[ Sen. 3, subscore: 2.00 ]: Here we show that , compared with its dominant allele , expressional non-reaction of xa13 to Xoo infection , not its protein composition , is the key factor for xa13-mediated resistance .
[ Sen. 2, subscore: 1.00 ]: The molecular mechanism of xa13-mediated resistance is largely unknown .
[ Sen. 7, subscore: 1.00 ]: These results suggest that race-specific pathogen-induced Xa13 expression is critical for infection .
[ Sen. 8, subscore: 1.00 ]: Thus , xa13 stands out from other R genes in that its functions in disease resistance are due to only the loss of pathogen-induced transcriptional motivation caused by natural selection .
| | Supplemental links/files: reference in endnote online text related articles pubmed citation | |
Score: 8.00 |
|---|
| Title: High-resolution genetic mapping of bacterial blight resistance gene Xa10 .
| | Author: Gu K Sangha JS Li Y Yin Z | | Journal: Theor Appl Genet Citation: V : 116 P : 155-63 Type: MEDLINE | | Literature: oryza Field: abstract Doc ID: pub17924090 Accession (PMID): 17924090 | | Abstract: Bacterial blight of rice , caused by Xanthomonas oryzae pv . oryzae ( Xoo ) , is the most devastating disease of rice ( Oryza sativa L ) .
Rice lines that carry resistance ( R ) gene Xa10 confer race-specific resistance to Xoo strains harboring avirulence ( Avr ) gene avrXa10 .
Here we report on genetic study , disease evaluation and fine genetic mapping of the Xa10 gene .
The inheritance of Xa10-mediated resistance to PXO99A ( pHM1avrXa10 ) did not follow typical Mendelian inheritance for single dominant gene in F2 population derived from IR24 x IRBB10 .
A locus might be present in IRBB10 that caused distorted segregation in F2 population .
To eliminate this locus , an F3 population ( F3-65 ) was identified , which showed normal Mendelian segregation ratio of 3 : 1 for resistance and susceptibility .
A new near-isogenic line ( F3-65-1743 ) of Xa10 in IR24 genetic background was developed and designated as IRBB10A .
IRBB10A retained similar resistance specificity as that of IRBB10 and provided complete resistance to PXO99A ( pHM1avrXa10 ) from seedling to adult stages .
Linkage analysis using existing RFLP markers and F2 mapping population mapped the Xa10 locus to the proximal side of E1981S with genetic distance at 0 . 93 cM .
With five new RFLP markers developed from the genomic sequence of Nipponbare , Xa10 was finely mapped at genetic distance of 0 . 28 cM between proximal marker M491 and distal marker M419 and co-segregated with markers S723 and M604 .
The physical distance between M491 and M419 on Nipponbare genome is 74 kb .
Seven genes have been annotated from this 74-kb region and six of them are possible Xa10 candidates .
The results of this study will be useful in Xa10 cloning and marker-assisted breeding .
| Matching Sentences:
[ Sen. 2, subscore: 1.00 ]: Rice lines that carry resistance ( R ) gene Xa10 confer race-specific resistance to Xoo strains harboring avirulence ( Avr ) gene avrXa10 .
[ Sen. 3, subscore: 1.00 ]: Here we report on genetic study , disease evaluation and fine genetic mapping of the Xa10 gene .
[ Sen. 4, subscore: 1.00 ]: The inheritance of Xa10-mediated resistance to PXO99A ( pHM1avrXa10 ) did not follow typical Mendelian inheritance for single dominant gene in F2 population derived from IR24 x IRBB10 .
[ Sen. 7, subscore: 1.00 ]: A new near-isogenic line ( F3-65-1743 ) of Xa10 in IR24 genetic background was developed and designated as IRBB10A .
[ Sen. 9, subscore: 1.00 ]: Linkage analysis using existing RFLP markers and F2 mapping population mapped the Xa10 locus to the proximal side of E1981S with genetic distance at 0 . 93 cM .
[ Sen. 10, subscore: 1.00 ]: With five new RFLP markers developed from the genomic sequence of Nipponbare , Xa10 was finely mapped at genetic distance of 0 . 28 cM between proximal marker M491 and distal marker M419 and co-segregated with markers S723 and M604 .
[ Sen. 12, subscore: 1.00 ]: Seven genes have been annotated from this 74-kb region and six of them are possible Xa10 candidates .
[ Sen. 13, subscore: 1.00 ]: The results of this study will be useful in Xa10 cloning and marker-assisted breeding .
| | Supplemental links/files: reference in endnote online text related articles pubmed citation | |
Score: 6.00 |
|---|
| Title: Characterization of Xanthomonas oryzae-responsive cis-acting element in the promoter of rice race-specific susceptibility gene Xa13 .
| | Author: Yuan T Li X Xiao J Wang S | | Journal: Mol Plant Citation: V : 4 P : 300-9 Type: MEDLINE | | Literature: oryza Field: abstract Doc ID: pub21208999 Accession (PMID): 21208999 | | Abstract: The rice Xa13 gene , whose promoter harbors a UPT ( up-regulated by transcription activator-like [ TAL ] effector ) box , UPT ( PthXo1 ) , plays a pivotal role in the race-specific pathogenicity caused by Xanthomonas oryzae pv . oryzae ( Xoo ) strain PXO99 .
PXO99 causes rice disease by inducing Xa13 .
It is unknown , however , whether the UPT ( PthXo1 ) box is the only PXO99-responsive cis-regulating elements in the activation of Xa13 expression .
We analyzed the expression of a series of end and site-truncated and site-mutated Xa13 promoters in rice and the binding of PXO99 protein to the intact , partial , or site-mutated UPT ( PthXo1 ) boxes .
In the Xa13 promoter , UPT ( PthXo1 ) box is the only Xoo-responsive cis-acting element that results in PXO99-induced Xa13 expression .
The 5-terminal second , third , and fourth nucleotides of the box are important for bacterial protein binding and gene activation ; mutation of any one of these sites abolished PXO99-induced gene expression .
Furthermore , the 3-half of the UPT ( PthXo1 ) box is also required for protein binding and gene activation .
These findings will enhance our understanding of the molecular mechanism of the interaction of rice and Xoo via UPT boxes and TAL effectors .
| Matching Sentences:
[ Sen. 5, subscore: 2.00 ]: In the Xa13 promoter , UPT ( PthXo1 ) box is the only Xoo-responsive cis-acting element that results in PXO99-induced Xa13 expression .
[ Sen. 1, subscore: 1.00 ]: The rice Xa13 gene , whose promoter harbors a UPT ( up-regulated by transcription activator-like [ TAL ] effector ) box , UPT ( PthXo1 ) , plays a pivotal role in the race-specific pathogenicity caused by Xanthomonas oryzae pv . oryzae ( Xoo ) strain PXO99 .
[ Sen. 2, subscore: 1.00 ]: PXO99 causes rice disease by inducing Xa13 .
[ Sen. 3, subscore: 1.00 ]: It is unknown , however , whether the UPT ( PthXo1 ) box is the only PXO99-responsive cis-regulating elements in the activation of Xa13 expression .
[ Sen. 4, subscore: 1.00 ]: We analyzed the expression of a series of end and site-truncated and site-mutated Xa13 promoters in rice and the binding of PXO99 protein to the intact , partial , or site-mutated UPT ( PthXo1 ) boxes .
| | Supplemental links/files: reference in endnote online text related articles pubmed citation | |
Score: 5.00 |
|---|
| Title: Genome-wide analysis of defense-responsive genes in bacterial blight resistance of rice mediated by the recessive R gene xa13 .
| | Author: Chu Z Ouyang Y Zhang J Yang H Wang S | | Journal: Mol . Genet . Genomics Citation: V : 271 ( 1 ) P : 111-20 Type: ARTICLE | | Literature: oryza Field: abstract Doc ID: pub14730444 Accession (PMID): 14730444 | | Abstract: Defense responses triggered by dominant and recessive disease resistance ( R ) genes are presumed to be regulated by different molecular mechanisms .
In order to characterize the genes activated in defense responses against bacterial blight mediated by the recessive R gene xa13 , two pathogen-induced subtraction cDNA libraries were constructed using the resistant rice line IRBB13--which carries xa13--and its susceptible , near-isogenic , parental line IR24 .
Clustering analysis of expressed sequence tags ( ESTs ) identified 702 unique expressed sequences as being involved in the defense responses triggered by xa13 ; 16% of these are new rice ESTs .
These sequences define 702 genes , putatively encoding a wide range of products , including defense-responsive genes commonly involved in different host-pathogen interactions , genes that have not previously been reported to be associated with pathogen-induced defense responses , and genes ( 38% ) with no homology to previously described functional genes .
In addition , R-like genes putatively encoding nucleotide-binding site/leucine rich repeat ( NBS-LRR ) and LRR receptor kinase proteins were observed to be induced in the disease resistance activated by xa13 .
A total of 568 defense-responsive ESTs were mapped to 588 loci on the rice molecular linkage map through bioinformatic analysis .
About 48% of the mapped ESTs co-localized with quantitative trait loci ( QTLs ) for resistance to various rice diseases , including bacterial blight , rice blast , sheath blight and yellow mottle virus .
Furthermore , some defense-responsive sequences were conserved at similar locations on different chromosomes .
These results reveal the complexity of xa13-mediated resistance .
The information obtained in this study provides a large source of candidate genes for understanding the molecular bases of defense responses activated by recessive R genes and of quantitative disease resistance . | Matching Sentences:
[ Sen. 2, subscore: 2.00 ]: In order to characterize the genes activated in defense responses against bacterial blight mediated by the recessive R gene xa13 , two pathogen-induced subtraction cDNA libraries were constructed using the resistant rice line IRBB13--which carries xa13--and its susceptible , near-isogenic , parental line IR24 .
[ Sen. 3, subscore: 1.00 ]: Clustering analysis of expressed sequence tags ( ESTs ) identified 702 unique expressed sequences as being involved in the defense responses triggered by xa13 ; 16% of these are new rice ESTs .
[ Sen. 5, subscore: 1.00 ]: In addition , R-like genes putatively encoding nucleotide-binding site/leucine rich repeat ( NBS-LRR ) and LRR receptor kinase proteins were observed to be induced in the disease resistance activated by xa13 .
[ Sen. 9, subscore: 1.00 ]: These results reveal the complexity of xa13-mediated resistance .
| | Supplemental links/files: reference in endnote online text related articles pubmed citation | |
Score: 5.00 |
|---|
| Title: Promoter mutations of an essential gene for pollen development result in disease resistance in rice .
| | Author: Chu Z Yuan M Yao J Ge X Yuan B Xu C Li X Fu B Li Z Bennetzen JL Zhang Q Wang S | | Journal: Genes Dev .
Citation: V : 20 ( 10 ) P : 1250-5 Type: ARTICLE | | Literature: oryza Field: abstract Doc ID: pub16648463 Accession (PMID): 16648463 | | Abstract: Disease resistance and sexual reproductive development are generally considered as separate biological processes , regulated by different sets of genes .
Here we show that xa13 , a recessive allele conferring disease resistance against bacterial blight , one of the most devastating rice diseases worldwide , plays a key role in both disease resistance and pollen development .
The dominant allele , Xa13 , is required for both bacterial growth and pollen development .
Promoter mutations in Xa13 cause down-regulation of expression during host-pathogen interaction , resulting in the fully recessive xa13 that confers race-specific resistance .
The recessive xa13 allele represents a new type of plant disease resistance . | Matching Sentences:
[ Sen. 4, subscore: 2.00 ]: Promoter mutations in Xa13 cause down-regulation of expression during host-pathogen interaction , resulting in the fully recessive xa13 that confers race-specific resistance .
[ Sen. 2, subscore: 1.00 ]: Here we show that xa13 , a recessive allele conferring disease resistance against bacterial blight , one of the most devastating rice diseases worldwide , plays a key role in both disease resistance and pollen development .
[ Sen. 3, subscore: 1.00 ]: The dominant allele , Xa13 , is required for both bacterial growth and pollen development .
[ Sen. 5, subscore: 1.00 ]: The recessive xa13 allele represents a new type of plant disease resistance .
| | Supplemental links/files: reference in endnote online text related articles pubmed citation | |
Score: 5.00 |
|---|
| Title: The bacterial pathogen Xanthomonas oryzae overcomes rice defenses by regulating host copper redistribution .
| | Author: Yuan M Chu Z Li X Xu C Wang S | | Journal: Plant Cell Citation: V : 22 P : 3164-76 Type: MEDLINE | | Literature: oryza Field: abstract Doc ID: pub20852017 Accession (PMID): 20852017 | | Abstract: Pathogen effectors are virulence factors causing plant diseases .
How the host targets of these effectors facilitate pathogen infection is largely unknown .
An effector of Xanthomonas oryzae pv oryzae ( Xoo ) transcriptionally activates rice ( Oryza sativa ) susceptibility gene Xa13 to cause bacterial blight disease .
Xa13 encodes an indispensable plasma membrane protein of the MtN3/saliva family , which is prevalent in eukaryotes with unknown biochemical function .
We show that the XA13 protein cooperates with two other proteins , COPT1 and COPT5 , to promote removal of copper from xylem vessels , where Xoo multiplies and spreads to cause disease .
Copper , an essential micronutrient of plants and an important element for a number of pesticides in agriculture , suppresses Xoo growth .
Xoo strain PXO99 is more sensitive to copper than other strains ; its infection of rice is associated with activation of XA13 , COPT1 , and COPT5 , which modulate copper redistribution in rice .
The involvement of XA13 in copper redistribution has led us to propose a mechanism of bacterial virulence .
| Matching Sentences:
[ Sen. 3, subscore: 1.00 ]: An effector of Xanthomonas oryzae pv oryzae ( Xoo ) transcriptionally activates rice ( Oryza sativa ) susceptibility gene Xa13 to cause bacterial blight disease .
[ Sen. 4, subscore: 1.00 ]: Xa13 encodes an indispensable plasma membrane protein of the MtN3/saliva family , which is prevalent in eukaryotes with unknown biochemical function .
[ Sen. 5, subscore: 1.00 ]: We show that the XA13 protein cooperates with two other proteins , COPT1 and COPT5 , to promote removal of copper from xylem vessels , where Xoo multiplies and spreads to cause disease .
[ Sen. 7, subscore: 1.00 ]: Xoo strain PXO99 is more sensitive to copper than other strains ; its infection of rice is associated with activation of XA13 , COPT1 , and COPT5 , which modulate copper redistribution in rice .
[ Sen. 8, subscore: 1.00 ]: The involvement of XA13 in copper redistribution has led us to propose a mechanism of bacterial virulence .
| | Supplemental links/files: reference in endnote online text related articles pubmed citation | |
Score: 5.00 |
|---|
| Title: Gene silencing using the recessive rice bacterial blight resistance gene xa13 as a new paradigm in plant breeding .
| | Author: Li C Wei J Lin Y Chen H | | Journal: Plant Cell Rep Citation: V : 31 P : 851-62 Type: In-Process | | Literature: oryza Field: abstract Doc ID: pub22218673 Accession (PMID): 22218673 | | Abstract: Resistant germplasm resources are valuable for developing resistant varieties in agricultural production .
However , recessive resistance genes are usually overlooked in hybrid breeding .
Compared with dominant traits , however , they may confer resistance to different pathogenic races or pest biotypes with different mechanisms of action .
The recessive rice bacterial blight resistance gene xa13 , also involved in pollen development , has been cloned and its resistance mechanism has been recently characterized .
This report describes the conversion of bacterial blight resistance mediated by the recessive xa13 gene into a dominant trait to facilitate its use in a breeding program .
This was achieved by knockdown of the corresponding dominant allele Xa13 in transgenic rice using recently developed artificial microRNA technology .
Tissue-specific promoters were used to exclude most of the expression of artificial microRNA in the anther to ensure that Xa13 functioned normally during pollen development .
A battery of highly bacterial blight resistant transgenic plants with normal seed setting rates were acquired , indicating that highly specific gene silencing had been achieved .
Our success with xa13 provides a paradigm that can be adapted to other recessive resistance genes .
| Matching Sentences:
[ Sen. 4, subscore: 1.00 ]: The recessive rice bacterial blight resistance gene xa13 , also involved in pollen development , has been cloned and its resistance mechanism has been recently characterized .
[ Sen. 5, subscore: 1.00 ]: This report describes the conversion of bacterial blight resistance mediated by the recessive xa13 gene into a dominant trait to facilitate its use in a breeding program .
[ Sen. 6, subscore: 1.00 ]: This was achieved by knockdown of the corresponding dominant allele Xa13 in transgenic rice using recently developed artificial microRNA technology .
[ Sen. 7, subscore: 1.00 ]: Tissue-specific promoters were used to exclude most of the expression of artificial microRNA in the anther to ensure that Xa13 functioned normally during pollen development .
[ Sen. 9, subscore: 1.00 ]: Our success with xa13 provides a paradigm that can be adapted to other recessive resistance genes .
| | Supplemental links/files: reference in endnote online text related articles pubmed citation | |
Score: 5.00 |
|---|
| 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 Citation: V : 95 ( 4 ) P : 1663-8 Type: ARTICLE | | Literature: oryza Field: abstract Doc ID: pub9465073 Accession (PMID): 9465073 | | 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: 2.00 ]: 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 .
[ Sen. 1, subscore: 1.00 ]: The Xa1 gene in rice confers resistance to Japanese race 1 of Xanthomonas oryzae pv . oryzae , the causal pathogen of bacterial blight ( BB ) .
[ Sen. 2, subscore: 1.00 ]: We isolated the Xa1 gene by a map-based cloning strategy .
[ Sen. 4, subscore: 1.00 ]: 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 .
| | Supplemental links/files: reference in endnote online text related articles pubmed citation | |
Score: 4.00 |
|---|
| Title: Targeting xa13 , a recessive gene for bacterial blight resistance in rice .
| | Author: Chu Z Fu B Yang H Xu C Li Z Sanchez A Park YJ Bennetzen JL Zhang Q Wang S | | Journal: Theor . Appl . Genet . Citation: V : 112 ( 3 ) P : 455-61 Type: ARTICLE | | Literature: oryza Field: abstract Doc ID: pub16328230 Accession (PMID): 16328230 | | Abstract: Bacterial blight , caused by Xanthomonas oryzae pv . oryzae ( Xoo ) , is one of the most serious diseases of rice worldwide .
Thirty bacterial blight resistance ( R ) genes ( 21 dominant genes and 9 recessive genes ) in rice have been identified .
They are the main sources for the genetic improvement of rice for resistance to Xoo .
However , little is known about the recessive R genes .
To clone and characterize the recessive R genes , we fine-mapped xa13 , a fully recessive gene for Xoo resistance , to a DNA fragment of 14 . 8 kb using the map-based cloning strategy and a series of sequence-based molecular markers .
Sequence analysis of this fragment indicated that this region contains only two apparently intact candidate genes ( an extensin-like gene and a homologue of nodulin MtN3 ) and the 5 end of a predicted hypothetical gene .
These results will greatly facilitate the isolation and characterization of xa13 .
Four PCR-based markers , E6a , SR6 , ST9 and SR11 that were tightly linked to the xa13 locus , were also developed .
These markers will be useful tools for the marker-assisted selection of xa13 in breeding programs . | Matching Sentences:
[ Sen. 5, subscore: 1.00 ]: To clone and characterize the recessive R genes , we fine-mapped xa13 , a fully recessive gene for Xoo resistance , to a DNA fragment of 14 . 8 kb using the map-based cloning strategy and a series of sequence-based molecular markers .
[ Sen. 7, subscore: 1.00 ]: These results will greatly facilitate the isolation and characterization of xa13 .
[ Sen. 8, subscore: 1.00 ]: Four PCR-based markers , E6a , SR6 , ST9 and SR11 that were tightly linked to the xa13 locus , were also developed .
[ Sen. 9, subscore: 1.00 ]: These markers will be useful tools for the marker-assisted selection of xa13 in breeding programs .
| | Supplemental links/files: reference in endnote online text related articles pubmed citation | |
Score: 4.00 |
|---|
| Title: Detection of bacterial blight resistance genes in basmati rice landraces .
| | Author: Ullah I Jamil S Iqbal MZ Shaheen HL Hasni SM Jabeen S Mehmood A Akhter M | | Journal: Genet Mol Res Citation: V : 11 P : 1960-6 Type: In-Data-Review | | Literature: oryza Field: abstract Doc ID: pub22869552 Accession (PMID): 22869552 | | Abstract: Aromatic basmati rice is vulnerable to bacterial blight disease .
Genes conferring resistance to bacterial blight have been identified in coarse rice ; however , their incorporation into basmati varieties compromises the prized basmati aroma .
We identified bacterial blight resistance genes Xa4 , xa5 , Xa7 , and xa13 in 52 basmati landraces and five basmati cultivars using PCR markers .
The Xa7 gene was found to be the most prevalent among the cultivars and landraces .
The cultivars Basmati-385 and Basmati-2000 also contained the Xa4 gene ; however , xa5 and xa13 were confined to landraces only .
Ten landraces were found to have multiple resistance genes .
Landraces Basmati-106 , Basmati-189 and Basmati-208 contained Xa4 and Xa7 genes .
Whereas , landraces Basmati-122 , Basmati-427 , Basmati-433 were observed to have xa5 and Xa7 genes .
Landraces Basmati-48 , Basmati-51A , Basmati-334 , and Basmati-370A possessed Xa7 and xa13 genes .
The use of landraces containing recessive genes xa5 and xa13 as donor parents in hybridization with cultivars Basmati-385 and Basmati-2000 , which contain the genes Xa4 and Xa7 , will expedite efforts to develop bacterial blight-resistant basmati rice cultivars through marker assisted selection , based on a pyramiding approach , without compromising aroma and grain quality .
| Matching Sentences:
[ Sen. 3, subscore: 1.00 ]: We identified bacterial blight resistance genes Xa4 , xa5 , Xa7 , and xa13 in 52 basmati landraces and five basmati cultivars using PCR markers .
[ Sen. 5, subscore: 1.00 ]: The cultivars Basmati-385 and Basmati-2000 also contained the Xa4 gene ; however , xa5 and xa13 were confined to landraces only .
[ Sen. 9, subscore: 1.00 ]: Landraces Basmati-48 , Basmati-51A , Basmati-334 , and Basmati-370A possessed Xa7 and xa13 genes .
[ Sen. 10, subscore: 1.00 ]: The use of landraces containing recessive genes xa5 and xa13 as donor parents in hybridization with cultivars Basmati-385 and Basmati-2000 , which contain the genes Xa4 and Xa7 , will expedite efforts to develop bacterial blight-resistant basmati rice cultivars through marker assisted selection , based on a pyramiding approach , without compromising aroma and grain quality .
| | Supplemental links/files: reference in endnote online text related articles pubmed citation | |
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 Citation: V : 159 ( 2 ) P : 757-65 Type: ARTICLE | | Literature: oryza Field: abstract Doc ID: pub11606550 Accession (PMID): 11606550 | | 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. 9, subscore: 1.00 ]: In contrast , xa13 was completely recessive , had no residual effects against the virulent races , and showed more pronounced race specificity .
[ 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 ) .
| | Supplemental links/files: reference in endnote online text related articles pubmed citation | |
Score: 3.00 |
|---|
| Title: Os8N3 is a host disease-susceptibility gene for bacterial blight of rice .
| | Author: Yang B Sugio A White FF .
| | Journal: Proc . Natl . Acad . Sci . USA Citation: V : 103 ( 27 ) P : 10503-8 Type: ARTICLE | | Literature: oryza Field: abstract Doc ID: pub16798873 Accession (PMID): 16798873 | | Abstract: Many bacterial diseases of plants depend on the interaction of type III effector genes of the pathogen and disease-susceptibility genes of the host The host susceptibility genes are largely unknown .
Here , we show that expression of the rice gene Os8N3 , a member of the MtN3 gene family from plants and animals , is elevated upon infection by Xanthomonas oryzae pv . oryzae strain PXO99 ( A ) and depends on the type III effector gene pthXo1 .
Os8N3 resides near xa13 , and PXO99 ( A ) failed to induce Os8N3 in rice lines with xa13 .
Silencing of Os8N3 by inhibitory RNA produced plants that were resistant to infection by strain PXO99 ( A ) yet remained susceptible to other strains of the pathogen .
The effector gene avrXa7 from strain PXO86 enabled PXO99 ( A ) compatibility on either xa13 or Os8N3-silenced plants .
The findings indicate that Os8N3 is a host susceptibility gene for bacterial blight targeted by the type III effector PthXo1 .
The results support the hypothesis that X oryzae pv . oryzae commandeers the regulation of otherwise developmentally regulated host genes to induce a state of disease susceptibility .
Furthermore , the results support a model in which the pathogen induces disease susceptibility in a gene-for-gene manner . | Matching Sentences:
[ Sen. 3, subscore: 2.00 ]: Os8N3 resides near xa13 , and PXO99 ( A ) failed to induce Os8N3 in rice lines with xa13 .
[ Sen. 5, subscore: 1.00 ]: The effector gene avrXa7 from strain PXO86 enabled PXO99 ( A ) compatibility on either xa13 or Os8N3-silenced plants .
| | Supplemental links/files: reference in endnote online text related articles pubmed citation | |
Score: 3.00 |
|---|
| 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 Citation: V : 32 P : 989-96 Type: MEDLINE | | Literature: oryza Field: abstract Doc ID: pub20349335 Accession (PMID): 20349335 | | 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. 6, subscore: 2.00 ]: 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 .
[ 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 .
| | Supplemental links/files: reference in endnote online text related articles pubmed citation | |
Score: 2.00 |
|---|
| Title: The C terminus of AvrXa10 can be replaced by the transcriptional activation domain of VP16 from the herpes simplex virus .
| | Author: Zhu W Yang B Wills N Johnson LB White FF .
| | Journal: Plant Cell Citation: V : 11 ( 9 ) P : 1665-74 Type: ARTICLE | | Literature: oryza Field: abstract Doc ID: pub10488234 Accession (PMID): 10488234 | | Abstract: The avirulence gene avrXa10 of Xanthomonas oryzae pv oryzae directs the elicitation of resistance in a gene-for-gene manner in rice lines carrying the resistance gene Xa10 .
We have localized a transcriptional activator domain in the C terminus of AvrXa10 by using amino acid replacement mutagenesis .
One mutant , with replacements at three hydrophobic amino acid residues in the C-terminal domain , was defective for transcriptional activation in yeast and avirulence activity in rice .
The activation domain from the herpes virus protein VP16 restored the ability of the bacteria expressing the hybrid protein to elicit a resistance reaction .
Elicitation was specific for Xa10 , and the reaction had the hallmarks of the response to AvrXa10 .
The results indicate that a domain with the properties of a transcriptional activator plays a critical role in AvrXa10 function .
The results also indicate that the protein has the potential to interact with the plant transcriptional program , although a role for the domain in the stability or conformation of the protein in the plant can not be excluded .
In a broader sense , the transcriptional activation domain of avrXa10 may represent a prokaryotic version of the acidic transcriptional activation domain , which heretofore has been found exclusively in eukaryotes . | Matching Sentences:
[ Sen. 1, subscore: 1.00 ]: The avirulence gene avrXa10 of Xanthomonas oryzae pv oryzae directs the elicitation of resistance in a gene-for-gene manner in rice lines carrying the resistance gene Xa10 .
[ Sen. 5, subscore: 1.00 ]: Elicitation was specific for Xa10 , and the reaction had the hallmarks of the response to AvrXa10 .
| | Supplemental links/files: reference in endnote online text related articles pubmed citation | |
Score: 2.00 |
|---|
| Title: Predicting durability of a disease resistance gene based on an assessment of the fitness loss and epidemiological consequences of avirulence gene mutation .
| | Author: Vera Cruz CM Bai J Ona I Leung H Nelson RJ Mew TW Leach JE .
| | Journal: Proc . Natl . Acad . Sci . USA Citation: V : 97 ( 25 ) P : 13500-5 Type: ARTICLE | | Literature: oryza Field: abstract Doc ID: pub11095723 Accession (PMID): 11095723 | | Abstract: Durability of plant disease resistance ( R ) genes may be predicted if the cost of pathogen adaptation to overcome resistance is understood .
Adaptation of the bacterial blight pathogen , Xanthomonas oryzae pv . oryzae ( Xoo ) , to virulence in rice is the result of the loss of pathogen avirulence gene function , but little is known about its effect on aggressiveness under field conditions .
We evaluated the cost in pathogenic fitness ( aggressiveness and persistence ) associated with adaptation of Xoo to virulence on near-isogenic rice lines with single R genes ( Xa7 , Xa10 , and Xa4 ) at two field sites endemic for bacterial blight .
Disease severity was high in all 3 years on all lines except the line with Xa7 .
Of two Xoo lineages ( groups of strains inferred to be clonally related based on DNA fingerprinting ) detected , one , lineage C , dominated the pathogen population at both sites .
All Xoo strains were virulent to Xa4 , whereas only lineage C strains were virulent to Xa10 .
Only a few strains of lineage C were virulent to Xa7 .
Adaptation to virulence on Xa7 occurred through at least four different pathways and was associated with a reduction in aggressiveness .
Loss of avirulence and reduced aggressiveness were associated with mutations at the 3 terminus of the avrXa7 allele .
Strains most aggressive to Xa7 were not detected after the second year , suggesting they were less persistent than less aggressive strains .
These experiments support the prediction that Xa7 would be a durable R gene because of a fitness penalty in Xoo associated with adaptation to Xa7 . | Matching Sentences:
[ Sen. 3, subscore: 1.00 ]: We evaluated the cost in pathogenic fitness ( aggressiveness and persistence ) associated with adaptation of Xoo to virulence on near-isogenic rice lines with single R genes ( Xa7 , Xa10 , and Xa4 ) at two field sites endemic for bacterial blight .
[ Sen. 6, subscore: 1.00 ]: All Xoo strains were virulent to Xa4 , whereas only lineage C strains were virulent to Xa10 .
| | Supplemental links/files: reference in endnote online text related articles pubmed citation | |
Score: 2.00 |
|---|
| Title: [ Construction of a deep coverage rice BAC library and identification of clones associated with disease-resistant genes ] | | Author: Wang WM Jiang GH Wang SQ Zhu LH Zhai WX .
| | Journal: Yi Chuan Xue Bao Citation: V : 28 ( 2 ) P : 120-8 Type: ARTICLE | | Literature: oryza Field: abstract Doc ID: pub11233255 Accession (PMID): 11233255 | | Abstract: A BAC library for IRBB56 , an accession pyramiding Xa4 , xa5 and xa13 three bacterial blight resistance genes , was constructed .
The library contains 55 , 296 clones with an average insert size of 132 kb .
Based on a haploid genome size of 450 Mb , the coverage of the library was about 14 genome equivalents that make it one of the most comprehensive BAC libraries available in rice and provide 99 . 99% possibility to isolate any interested rice genes or sequences in the library .
To determine the representation of organelle DNA homologues in the library , the library was screened with three different chloroplast genes and four mitochondrial genes , respectively .
Results from this screening showed that less than 1% of clones in the library contain organelle genomic DNA homologues .
Then , DNA markers on three different chromosomes linked to Xa4 , xa5 , and xa13 , and a PCR fragment of rice UROD gene , were used to screen the library resulting in a range of 11-106 hits that will promote the isolation of these genes .
The deep coverage and the large insert size of the library will facilitate physical mapping , isolation , and cloning of rice genes . | Matching Sentences:
[ Sen. 1, subscore: 1.00 ]: A BAC library for IRBB56 , an accession pyramiding Xa4 , xa5 and xa13 three bacterial blight resistance genes , was constructed .
[ Sen. 6, subscore: 1.00 ]: Then , DNA markers on three different chromosomes linked to Xa4 , xa5 , and xa13 , and a PCR fragment of rice UROD gene , were used to screen the library resulting in a range of 11-106 hits that will promote the isolation of these genes .
| | Supplemental links/files: reference in endnote online text related articles pubmed citation | |
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 . Citation: V : 39 ( 7-8 ) P : 261-78 Type: ARTICLE | | Literature: oryza Field: abstract Doc ID: pub11590832 Accession (PMID): 11590832 | | 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 .
| | Supplemental links/files: reference in endnote online text related articles pubmed citation | |
Score: 2.00 |
|---|
| Title: Recessive bacterial leaf blight resistance in rice : complexity , challenges and strategy .
| | Author: Kottapalli KR Kottapalli P Agrawal GK Kikuchi S Rakwal R | | Journal: Biochem . Biophys . Res . Commun . Citation: V : 355 ( 2 ) P : 295-301 Type: ARTICLE | | Literature: oryza Field: abstract Doc ID: pub17307154 Accession (PMID): 17307154 | | Abstract: Physical mapping and map-based cloning strategies are routinely used for identification of candidate genes for major qualitative traits in rice .
Such strategies have enabled mapping and characterization of dominant bacterial leaf blight ( blb ) resistance genes , but little progress has been made in case of the recessive resistance genes .
Two recent studies on map-based cloning of xa5 and xa13 recessive blb resistance genes identified the general transcription factor IIA gamma subunit ( TFIIAgamma ) and the nodulin MtN21 as candidates , respectively .
Subsequently , two other reports have raised discussion on whether the identified candidates are indeed recessive resistance genes , and are sufficient to confer blb resistance in rice .
Based on published evidence , and our extensive in silico analyses of the genomic environment around xa5 and xa13 regions , we propose that the recessive gene mediated resistance mechanism is more complex and might not be governed by a single gene .
| Matching Sentences:
[ Sen. 3, subscore: 1.00 ]: Two recent studies on map-based cloning of xa5 and xa13 recessive blb resistance genes identified the general transcription factor IIA gamma subunit ( TFIIAgamma ) and the nodulin MtN21 as candidates , respectively .
[ Sen. 5, subscore: 1.00 ]: Based on published evidence , and our extensive in silico analyses of the genomic environment around xa5 and xa13 regions , we propose that the recessive gene mediated resistance mechanism is more complex and might not be governed by a single gene .
| | Supplemental links/files: reference in endnote online text related articles pubmed citation | |
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 Citation: V : 4 P : 400-7 Type: In-Process | | Literature: oryza Field: abstract Doc ID: pub19253322 Accession (PMID): 19253322 | | 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 .
| | Supplemental links/files: reference in endnote online text related articles pubmed citation | |
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 Citation: V : P : Type: Publisher | | Literature: oryza Field: abstract Doc ID: pub21793000 Accession (PMID): 21793000 | | 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 .
| | Supplemental links/files: reference in endnote online text related articles pubmed citation | |
Score: 1.00 |
|---|
| Title: Plant disease resistance genes encode members of an ancient and diverse protein family within the nucleotide-binding superfamily .
| | Author: Meyers BC Dickerman AW Michelmore RW Sivaramakrishnan S Sobral BW Young ND .
| | Journal: Plant J Citation: V : 20 ( 3 ) P : 317-32 Type: ARTICLE | | Literature: oryza Field: abstract Doc ID: pub10571892 Accession (PMID): 10571892 | | Abstract: The nucleotide binding site ( NBS ) is a characteristic domain of many plant resistance gene products .
An increasing number of NBS-encoding sequences are being identified through gene cloning , PCR amplification with degenerate primers , and genome sequencing projects .
The NBS domain was analyzed from 14 known plant resistance genes and more than 400 homologs , representing 26 genera of monocotyledonous , dicotyle-donous and one coniferous species .
Two distinct groups of diverse sequences were identified , indicating divergence during evolution and an ancient origin for these sequences .
One group was comprised of sequences encoding an N-terminal domain with Toll/Interleukin-1 receptor homology ( TIR ) , including the known resistance genes , N , M , L6 , RPP1 and RPP5 .
Surprisingly , this group was entirely absent from monocot species in searches of both random genomic sequences and large collections of ESTs .
A second group contained monocot and dicot sequences , including the known resistance genes , RPS2 , RPM1 , I2 , Mi , Dm3 , Pi-B , Xa1 , RPP8 , RPS5 and Prf .
Amino acid signatures in the conserved motifs comprising the NBS domain clearly distinguished these two groups .
The Arabidopsis genome is estimated to contain approximately 200 genes that encode related NBS motifs ; TIR sequences were more abundant and outnumber non-TIR sequences threefold .
The Arabidopsis NBS sequences currently in the databases are located in approximately 21 genomic clusters and 14 isolated loci .
NBS-encoding sequences may be more prevalent in rice .
The wide distribution of these sequences in the plant kingdom and their prevalence in the Arabidopsis and rice genomes indicate that they are ancient , diverse and common in plants .
Sequence inferences suggest that these genes encode a novel class of nucleotide-binding proteins .
| Matching Sentences:
[ Sen. 7, subscore: 1.00 ]: A second group contained monocot and dicot sequences , including the known resistance genes , RPS2 , RPM1 , I2 , Mi , Dm3 , Pi-B , Xa1 , RPP8 , RPS5 and Prf .
| | Supplemental links/files: reference in endnote online text related articles pubmed citation | |
Score: 1.00 |
|---|
| Title: [ Activities of superoxide dismutase in Xanthomonas oryzae pv . oryzae and its induction ] | | Author: Song F Ge X Zheng Z Hu X | | Journal: Wei Sheng Wu Xue Bao Citation: V : 40 ( 3 ) P : 301-5 Type: ARTICLE | | Literature: oryza Field: abstract Doc ID: pub12548996 Accession (PMID): 12548996 | | Abstract: The activities of superoxide dismutase ( SOD ) in Xanthomonas oryzae pv . oryzae were determined to demonstrate the correlation of SOD activities with the bacterial virulence .
In liquid culture , SOD activities of the tested strains reached the maxima at the end of lag phase and then declined .
The virulent strain PXO99A showed higher SOD activities than the avirulent strain PXO99A ( pBUavr Xa10 . F1 ) .
Analysis on the subcellular location indicated that SOD activities detected from the cytoplasm and periplasm were over 70% and 20%-30% of the total , respectively .
Treatment of the bacterial culture for 1 h with exogenous O2 at concentration of 50-800 mumol/L induced SOD activities of both the strains .
The treatment with 200 mumol/L resulted in the highest SOD activities .
The effect of exogenous O2 on SOD induction was more significant in 12 h-culture than in 24 h-culture , and more notable for the virulent strain PXO99A .
The treatment with exogenous O2 resulted in significantly decreased survival rate off both the strains .
The decreases of survival rate were greater in 24 h-culture than in 12 h-culture , and more significantly for the virulent strain than for the avirulent one . | Matching Sentences:
[ Sen. 3, subscore: 1.00 ]: The virulent strain PXO99A showed higher SOD activities than the avirulent strain PXO99A ( pBUavr Xa10 . F1 ) .
| | Supplemental links/files: reference in endnote online text related articles pubmed citation | |
Score: 1.00 |
|---|
| Title: High-resolution mapping of the leaf rust disease resistance gene Lr1 in wheat and characterization of BAC clones from the Lr1 locus .
| | Author: Ling HQ Zhu Y Keller B | | Journal: Theor . Appl . Genet . Citation: V : 106 ( 5 ) P : 875-82 Type: ARTICLE | | Literature: oryza Field: abstract Doc ID: pub12647062 Accession (PMID): 12647062 | | Abstract: Leaf rust is the most common disease in wheat production .
There are more than 45 specific resistance genes described and used in wheat breeding to control epidemics of leaf rust , but none of them has been cloned .
The leaf rust disease resistance gene 1 ( Lr1 ) is a good model gene for isolation by map-based cloning because it is a single , dominant gene which is located in the distal region of chromosome 5DL of wheat .
As the first step towards the isolation of this gene we constructed a high-resolution genetic map in the region of the Lr1 locus by saturation mapping of two large segregating F ( 2 ) populations ( Thatcher Lr1 x Thatcher , Thatcher Lr1 x Frisal ) .
The resistance gene Lr1 was delimited in a 0 . 16-cM region between the RFLP markers ABC718 and PSR567 ( 0 . 12 cM from ABC718 and 0 . 04 cM from PSR567 ) .
A genomic BAC library of Aegilops tauschii ( D genome ) was screened using the RFLP markers ABC718 and PSR567 .
Five positive BAC clones were identified by ABC718 and four clones by PSR567 .
Two NBS-LRR type of resistance gene analogs , which encode proteins highly homologous to the bacterial blight disease resistance protein Xa1 of rice , were identified on BAC clones isolated with PSR567 .
Polymorphic BAC end probes were isolated from both ends of a 105-kb large BAC clone identified by ABC718 .
The end probes were mapped at the same locus as ABC718 , and no recombination event was found within 105 kb around ABC718 in our analysis of more than 4 , 000 gametes .
| Matching Sentences:
[ Sen. 8, subscore: 1.00 ]: Two NBS-LRR type of resistance gene analogs , which encode proteins highly homologous to the bacterial blight disease resistance protein Xa1 of rice , were identified on BAC clones isolated with PSR567 .
| | Supplemental links/files: reference in endnote online text related articles pubmed citation | |
Score: 1.00 |
|---|
| 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 .
Citation: V : 17 ( 6 ) P : 602-12 Type: ARTICLE | | Literature: oryza Field: abstract Doc ID: pub15195943 Accession (PMID): 15195943 | | 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. 7, subscore: 1.00 ]: These null mutants do not affect AvrXa7 and AvrXa10 activities , as observed in inoculation experiments with Xa7 and Xa10-rice lines .
| | Supplemental links/files: reference in endnote online text related articles pubmed citation | |
Score: 1.00 |
|---|
| Title: Characterization of the hrpF pathogenicity peninsula of Xanthomonas oryzae pv . oryzae .
| | Author: Sugio A Yang B White FF .
| | Journal: Mol .
Plant Microbe Interact .
Citation: V : 18 ( 6 ) P : 546-54 Type: ARTICLE | | Literature: oryza Field: abstract Doc ID: pub15986924 Accession (PMID): 15986924 | | Abstract: The hrp gene cluster of Xanthomonas spp . contains genes for the assembly and function of a type III secretion system ( TTSS ) .
The hrpF genes reside in a region between hpaB and the right end of the hrp cluster .
The region of the hrpF gene of Xanthomonas oryzae pv . oryzae is bounded by two IS elements and also contains a homolog of hpaF of X campestris pv . vesicatoria and two newly identified genes , hpa3 and hpa4 .
A comparison of the hrp gene clusters of different species of Xanthomonas revealed that the hrpF region is a constant yet more variable peninsula of the hrp pathogenicity island .
Mutations in hpaF , hpa3 , and hpa4 had no effect on virulence , whereas hrpF mutants were severely reduced in virulence on susceptible rice cultivars .
The hrpF genes from X campestris pv . vesicatoria , X campestris pv . campestris , and X axonopodis pv . citri each were capable of restoring virulence to the hrpF mutant of X oryzae pv . oryzae .
Correspondingly , none of the Xanthomonas pathovars with hrpF from X oryzae pv . oryzae elicited a hypersensitive reaction in their respective hosts .
Therefore , no evidence was found for hrpF as a host-specialization factor .
In contrast to the loss of Bs3-dependent reactions by hrpF mutants of X campestris pv . vesicatoria , hrpF mutants of X oryzae pv . oryzae with either avrXa10 or avrXa7 elicited hypersensitive reactions in rice cultivars with the corresponding R genes .
A double hrpFxoo-hpa1 mutant also elicited an Xa10-dependent resistance reaction .
Thus , loss of hrpF , hpal , or both may reduce delivery or effectiveness of type III effectors .
However , the mutations did not completely prevent the delivery of effectors from X oryzae pv . oryzae into the host cells . | Matching Sentences:
[ Sen. 10, subscore: 1.00 ]: A double hrpFxoo-hpa1 mutant also elicited an Xa10-dependent resistance reaction .
| | Supplemental links/files: reference in endnote online text related articles pubmed citation | |
Score: 1.00 |
|---|
| Title: Recessive resistance genes and the Oryza sativa-Xanthomonas oryzae pv . oryzae pathosystem .
| | Author: Iyer-Pascuzzi AS McCouch SR | | Journal: Mol Plant Microbe Interact Citation: V : 20 P : 731-9 Type: MEDLINE | | Literature: oryza Field: abstract Doc ID: pub17601161 Accession (PMID): 17601161 | | Abstract: Though recessive resistance is well-studied in viral systems , little is understood regarding the phenomenon in plant-bacterial interactions .
The Oryza sativa-Xanthomonas oryzae pv . orzyae pathosystem provides an excellent opportunity to examine recessive resistance in plant-bacterial interactions , in which nine of 30 documented resistance ( R ) genes are recessively inherited .
Infestations of X oryzae pv . oryzae , the causal agent of bacterial blight , result in significant crop loss and damage throughout South and Southeast Asia .
Two recently cloned novel recessive R genes , xa5 and xa13 , have yielded insights to this system .
Like their viral counterparts , these bacterial recessive R gene products do not conform to the five commonly described classes of R proteins .
New findings suggest that such genes may more aptly be viewed as mutations in dominant susceptibility alleles and may also function in a gene-for-gene manner .
In this review , we discuss recent accomplishments in the understanding of recessively inherited R genes in the rice-bacterial blight pathosystem and suggest a new model for the function of recessive resistance in plant-bacterial interactions .
| Matching Sentences:
[ Sen. 4, subscore: 1.00 ]: Two recently cloned novel recessive R genes , xa5 and xa13 , have yielded insights to this system .
| | Supplemental links/files: reference in endnote online text related articles pubmed citation | |
Score: 1.00 |
|---|
| Title: Constitutive expression of a rice GTPase-activating protein induces defense responses .
| | Author: Cheung MY Zeng NY Tong SW Li WY Xue Y Zhao KJ Wang C Zhang Q Fu Y Sun Z Sun SS Lam HM | | Journal: New Phytol Citation: V : P : Type: Publisher | | Literature: oryza Field: abstract Doc ID: pub18466220 Accession (PMID): 18466220 | | Abstract: * G-proteins ( guanine nucleotide-binding proteins that usually exhibit GTPase activities ) and related signal transduction processes play important roles in mediating plant defense responses ; here , a rice ( Oryza sativa ) cDNA clone , OsGAP1 , encoding a GTPase-activating protein ( GAP ) that also contains a protein kinase C conserved region 2 ( C2 ) domain is reported .
* An interacting G-protein partner for the OsGAP1 protein was identified by yeast two-hybrid library screening and confirmed by co-immunoprecipitation ; the GTPase-activation activity of OsGAP1 on this interacting G-protein was demonstrated using in vitro assays .
* OsGAP1 was induced by wounding in rice and the presence of the R locus Xa14 enhances such induction .
* Gain-of-function tests in transgenic rice and Arabidopsis thaliana showed that constitutive expression of OsGAP1 led to increased resistance to bacterial pathogens in both monocots and dicots .
| Matching Sentences:
[ Sen. 3, subscore: 1.00 ]: * OsGAP1 was induced by wounding in rice and the presence of the R locus Xa14 enhances such induction .
| | Supplemental links/files: reference in endnote online text related articles pubmed citation | |
Score: 1.00 |
|---|
| Title: Constitutive expression of a rice GTPase-activating protein induces defense responses .
| | Author: Cheung MY Zeng NY Tong SW Li WY Xue Y Zhao KJ Wang C Zhang Q Fu Y Sun Z Sun SS Lam HM | | Journal: New Phytol Citation: V : 179 P : 530-45 Type: MEDLINE | | Literature: oryza Field: abstract Doc ID: pub19086295 Accession (PMID): 19086295 | | Abstract: G-proteins ( guanine nucleotide-binding proteins that usually exhibit GTPase activities ) and related signal transduction processes play important roles in mediating plant defense responses ; here , a rice ( Oryza sativa ) cDNA clone , OsGAP1 , encoding a GTPase-activating protein ( GAP ) that also contains a protein kinase C conserved region 2 ( C2 ) domain is reported .
An interacting G-protein partner for the OsGAP1 protein was identified by yeast two-hybrid library screening and confirmed by co-immunoprecipitation ; the GTPase-activation activity of OsGAP1 on this interacting G-protein was demonstrated using in vitro assays .
OsGAP1 was induced by wounding in rice and the presence of the R locus Xa14 enhances such induction .
Gain-of-function tests in transgenic rice and Arabidopsis thaliana showed that constitutive expression of OsGAP1 led to increased resistance to bacterial pathogens in both monocots and dicots .
| Matching Sentences:
[ Sen. 3, subscore: 1.00 ]: OsGAP1 was induced by wounding in rice and the presence of the R locus Xa14 enhances such induction .
| | Supplemental links/files: reference in endnote online text related articles pubmed citation | |
Score: 1.00 |
|---|
| Title: Promoter elements of rice susceptibility genes are bound and activated by specific TAL effectors from the bacterial blight pathogen , Xanthomonas oryzae pv . oryzae .
| | Author: Romer P Recht S Strauss T Elsaesser J Schornack S Boch J Wang S Lahaye T | | Journal: New Phytol Citation: V : 187 P : 1048-57 Type: MEDLINE | | Literature: oryza Field: abstract Doc ID: pub20345643 Accession (PMID): 20345643 | | Abstract: *Plant pathogenic bacteria of the genus Xanthomonas inject transcription activator-like effector ( TALe ) proteins that bind to and activate host promoters , thereby promoting disease or inducing plant defense .
TALes bind to corresponding UPT ( up-regulated by TALe ) promoter boxes via tandemly arranged 34/35-amino acid repeats .
Recent studies uncovered the TALe code in which two amino acid residues of each repeat define specific pairing to UPT boxes .
*Here we employed the TALe code to predict potential UPT boxes in TALe-induced host promoters and analyzed these via beta-glucuronidase ( GUS ) reporter and electrophoretic mobility shift assays ( EMSA ) .
*We demonstrate that the Xa13 , OsTFX1 and Os11N3 promoters from rice are induced directly by the Xanthomonas oryzae pv . oryzae TALes PthXo1 , PthXo6 and AvrXa7 , respectively .
We identified and functionally validated a UPT box in the corresponding rice target promoter for each TALe and show that box mutations suppress TALe-mediated promoter activation .
Finally , EMSA demonstrate that code-predicted UPT boxes interact specifically with corresponding TALes .
*Our findings show that variations in the UPT boxes of different rice accessions correlate with susceptibility or resistance of these accessions to the bacterial blight pathogen .
| Matching Sentences:
[ Sen. 5, subscore: 1.00 ]: *We demonstrate that the Xa13 , OsTFX1 and Os11N3 promoters from rice are induced directly by the Xanthomonas oryzae pv . oryzae TALes PthXo1 , PthXo6 and AvrXa7 , respectively .
| | Supplemental links/files: reference in endnote online text related articles pubmed citation | |
Score: 1.00 |
|---|
| Title: Rice xa13 recessive resistance to bacterial blight is defeated by induction of the disease susceptibility gene Os-11N3 .
| | Author: Antony G Zhou J Huang S Li T Liu B White F Yang B | | Journal: Plant Cell Citation: V : 22 P : 3864-76 Type: MEDLINE | | Literature: oryza Field: abstract Doc ID: pub21098734 Accession (PMID): 21098734 | | Abstract: The rice ( Oryza sativa ) gene xa13 is a recessive resistance allele of Os-8N3 , a member of the NODULIN3 ( N3 ) gene family , located on rice chromosome 8 .
Os-8N3 is a susceptibility ( S ) gene for Xanthomonas oryzae pv oryzae , the causal agent of bacterial blight , and the recessive allele is defeated by strains of the pathogen producing any one of the type III effectors AvrXa7 , PthXo2 , or PthXo3 , which are all members of the transcription activator-like ( TAL ) effector family .
Both AvrXa7 and PthXo3 induce the expression of a second member of the N3 gene family , here named Os-11N3 .
Insertional mutagenesis or RNA-mediated silencing of Os-11N3 resulted in plants with loss of susceptibility specifically to strains of X oryzae pv oryzae dependent on AvrXa7 or PthXo3 for virulence .
We further show that AvrXa7 drives expression of Os-11N3 and that AvrXa7 interacts and binds specifically to an effector binding element within the Os-11N3 promoter , lending support to the predictive models for TAL effector binding specificity .
The result indicates that variations in the TAL effector repetitive domains are driven by selection to overcome both dominant and recessive forms of resistance to bacterial blight in rice .
The finding that Os-8N3 and Os-11N3 encode closely related proteins also provides evidence that N3 proteins have a specific function in facilitating bacterial blight disease .
| Matching Sentences:
[ Sen. 1, subscore: 1.00 ]: The rice ( Oryza sativa ) gene xa13 is a recessive resistance allele of Os-8N3 , a member of the NODULIN3 ( N3 ) gene family , located on rice chromosome 8 .
| | Supplemental links/files: reference in endnote online text related articles pubmed citation | |
Score: 1.00 |
|---|
| Title: Inheritance of bacterial blight resistance in the rice cultivar Ajaya and high-resolution mapping of a major QTL associated with resistance .
| | Author: Sujatha K Natarajkumar P Laha GS Mishra B Rao KS Viraktamath BC Kirti PB Hari Y Balachandran SM Rajendrakumar P Ram T Hajira SK Madhav MS Neeraja CN Sundaram RM | | Journal: Genet Res ( Camb ) Citation: V : 93 P : 397-408 Type: In-Data-Review | | Literature: oryza Field: abstract Doc ID: pub22189605 Accession (PMID): 22189605 | | Abstract: SummaryThe cultivar Ajaya ( IET 8585 ) exhibits durable broad-spectrum resistance to bacterial blight ( BB ) disease of rice and is widely used as a resistance donor .
The present study was carried out to decipher the genetics of BB resistance in Ajaya and map the gene ( s ) conferring resistance .
Genetic analysis in the F2 indicated a quantitative/additive nature of resistance governed by two loci with equal effects .
Linked marker analysis and allelic tests revealed that one of the resistance genes is xa5 .
Sequence analysis of a 244 bp region of the second exon of the gene-encoding Transcription factor IIAgamma ( the candidate gene for xa5 ) confirmed the presence of xa5 .
Bulked-segregant analysis ( BSA ) revealed the putative location of the two quantitative trait loci ( QTLs ) /genes associated with resistance on chromosomes 5 and 8 .
Composite interval mapping located the first locus on Chr .
5S exactly in the genomic region spanned by xa5 and the second locus ( qtl BBR 8 . 1 ) on Chr .
8L .
Owing to its differential disease reaction with a set of seven hyper-virulent isolates of Xanthomonas oryzae , a map location on Chr .
8L , which was distinct from xa13 and data from allelism tests , the second resistance locus in Ajaya was determined to be novel and was designated as xaAj .
A contig map spanning xaAj was constructed in silico and the genomic region was delimited to a 13 . 5 kb physical interval In silico analysis of the genomic region spanning xaAj identified four putatively expressed candidate genes , one of which could be involved in imparting BB resistance in Ajaya along with xa5 .
| Matching Sentences:
[ Sen. 11, subscore: 1.00 ]: 8L , which was distinct from xa13 and data from allelism tests , the second resistance locus in Ajaya was determined to be novel and was designated as xaAj .
| | Supplemental links/files: reference in endnote online text related articles pubmed citation | |
Score: 1.00 |
|---|
| Title: AvrXa10 contains an acidic transcriptional activation domain in the functionally conserved C terminus .
| | Author: Zhu W Yang B Chittoor JM Johnson LB White FF .
| | Journal: Mol .
Plant Microbe Interact .
Citation: V : 11 ( 8 ) P : 824-32 Type: ARTICLE | | Literature: oryza Field: abstract Doc ID: pub9675896 Accession (PMID): 9675896 | | Abstract: The avrXa10 gene of Xanthomonas oryzae pv . oryzae , the causal agent of bacterial blight of rice , is a member of the avrBs3 avirulence gene family and directs the elicitation of resistance in a gene-for-gene manner on rice lines carrying the resistance gene Xa10 .
The carboxyl ( C ) terminus of AvrXa10 has a previously undescribed domain that is structurally similar to the acidic activation domain of many eukaryotic transcription factors in addition to three nuclear localization signal ( NLS ) sequences .
Removal of the C-terminal 38 codons containing the putative activation domain , but retaining the NLS sequences , was concomitant with the loss of avirulence activity .
The C-terminal coding regions of avrBs3 and avrXa7 can be replaced by the corresponding region of avrXa10 , and the genes retained specificity for the resistance genes Bs3 in pepper and Xa7 in rice , respectively .
The avrBs3 and avrXa7 avirulence activities of the hybrid genes were also lost upon removal of the terminal 38 codons .
When fused to the coding sequence of the Gal4 DNA binding domain , AvrXa10 activated transcription in yeast and Arabidopsis thaliana .
Removal of the carboxyl region severely reduced transcriptional activation .
AvrXa10 would have to be localized to the host cell nucleus to function autonomously in transcriptional activation .
Consistent with this requirement , mutations in all three NLS sequences of avrXa10 caused a loss in avirulence activity .
The findings demonstrate the requirement of the C terminus for AvrXa10 function and the potential for the members of this family of avirulence gene products to enter the host nucleus and alter host transcription . | Matching Sentences:
[ Sen. 1, subscore: 1.00 ]: The avrXa10 gene of Xanthomonas oryzae pv . oryzae , the causal agent of bacterial blight of rice , is a member of the avrBs3 avirulence gene family and directs the elicitation of resistance in a gene-for-gene manner on rice lines carrying the resistance gene Xa10 .
| | Supplemental links/files: reference in endnote online text related articles pubmed citation | |
Score: 1.00 |
|---|
| Title: Genome-wide analysis of defense-responsive genes in bacterial blight resistance of rice mediated by the recessive R gene xa13 .
| | Author: Chu Z Ouyang Y Zhang J Yang H Wang S | | Journal: Mol . Genet . Genomics Citation: V : 271 ( 1 ) P : 111-20 Type: ARTICLE | | Literature: oryza Field: title Doc ID: pub14730444 Accession (PMID): 14730444 | | Abstract: Defense responses triggered by dominant and recessive disease resistance ( R ) genes are presumed to be regulated by different molecular mechanisms .
In order to characterize the genes activated in defense responses against bacterial blight mediated by the recessive R gene xa13 , two pathogen-induced subtraction cDNA libraries were constructed using the resistant rice line IRBB13--which carries xa13--and its susceptible , near-isogenic , parental line IR24 .
Clustering analysis of expressed sequence tags ( ESTs ) identified 702 unique expressed sequences as being involved in the defense responses triggered by xa13 ; 16% of these are new rice ESTs .
These sequences define 702 genes , putatively encoding a wide range of products , including defense-responsive genes commonly involved in different host-pathogen interactions , genes that have not previously been reported to be associated with pathogen-induced defense responses , and genes ( 38% ) with no homology to previously described functional genes .
In addition , R-like genes putatively encoding nucleotide-binding site/leucine rich repeat ( NBS-LRR ) and LRR receptor kinase proteins were observed to be induced in the disease resistance activated by xa13 .
A total of 568 defense-responsive ESTs were mapped to 588 loci on the rice molecular linkage map through bioinformatic analysis .
About 48% of the mapped ESTs co-localized with quantitative trait loci ( QTLs ) for resistance to various rice diseases , including bacterial blight , rice blast , sheath blight and yellow mottle virus .
Furthermore , some defense-responsive sequences were conserved at similar locations on different chromosomes .
These results reveal the complexity of xa13-mediated resistance .
The information obtained in this study provides a large source of candidate genes for understanding the molecular bases of defense responses activated by recessive R genes and of quantitative disease resistance . | Matching Sentences:
[ Sen. 1, subscore: 1.00 ]: Genome-wide analysis of defense-responsive genes in bacterial blight resistance of rice mediated by the recessive R gene xa13 .
| | Supplemental links/files: reference in endnote online text related articles pubmed citation | |
Score: 1.00 |
|---|
| Title: Targeting xa13 , a recessive gene for bacterial blight resistance in rice .
| | Author: Chu Z Fu B Yang H Xu C Li Z Sanchez A Park YJ Bennetzen JL Zhang Q Wang S | | Journal: Theor . Appl . Genet . Citation: V : 112 ( 3 ) P : 455-61 Type: ARTICLE | | Literature: oryza Field: title Doc ID: pub16328230 Accession (PMID): 16328230 | | Abstract: Bacterial blight , caused by Xanthomonas oryzae pv . oryzae ( Xoo ) , is one of the most serious diseases of rice worldwide .
Thirty bacterial blight resistance ( R ) genes ( 21 dominant genes and 9 recessive genes ) in rice have been identified .
They are the main sources for the genetic improvement of rice for resistance to Xoo .
However , little is known about the recessive R genes .
To clone and characterize the recessive R genes , we fine-mapped xa13 , a fully recessive gene for Xoo resistance , to a DNA fragment of 14 . 8 kb using the map-based cloning strategy and a series of sequence-based molecular markers .
Sequence analysis of this fragment indicated that this region contains only two apparently intact candidate genes ( an extensin-like gene and a homologue of nodulin MtN3 ) and the 5 end of a predicted hypothetical gene .
These results will greatly facilitate the isolation and characterization of xa13 .
Four PCR-based markers , E6a , SR6 , ST9 and SR11 that were tightly linked to the xa13 locus , were also developed .
These markers will be useful tools for the marker-assisted selection of xa13 in breeding programs . | Matching Sentences:
[ Sen. 1, subscore: 1.00 ]: Targeting xa13 , a recessive gene for bacterial blight resistance in rice .
| | Supplemental links/files: reference in endnote online text related articles pubmed citation | |
Score: 1.00 |
|---|
| Title: High-resolution genetic mapping of bacterial blight resistance gene Xa10 .
| | Author: Gu K Sangha JS Li Y Yin Z | | Journal: Theor Appl Genet Citation: V : 116 P : 155-63 Type: MEDLINE | | Literature: oryza Field: title Doc ID: pub17924090 Accession (PMID): 17924090 | | Abstract: Bacterial blight of rice , caused by Xanthomonas oryzae pv . oryzae ( Xoo ) , is the most devastating disease of rice ( Oryza sativa L ) .
Rice lines that carry resistance ( R ) gene Xa10 confer race-specific resistance to Xoo strains harboring avirulence ( Avr ) gene avrXa10 .
Here we report on genetic study , disease evaluation and fine genetic mapping of the Xa10 gene .
The inheritance of Xa10-mediated resistance to PXO99A ( pHM1avrXa10 ) did not follow typical Mendelian inheritance for single dominant gene in F2 population derived from IR24 x IRBB10 .
A locus might be present in IRBB10 that caused distorted segregation in F2 population .
To eliminate this locus , an F3 population ( F3-65 ) was identified , which showed normal Mendelian segregation ratio of 3 : 1 for resistance and susceptibility .
A new near-isogenic line ( F3-65-1743 ) of Xa10 in IR24 genetic background was developed and designated as IRBB10A .
IRBB10A retained similar resistance specificity as that of IRBB10 and provided complete resistance to PXO99A ( pHM1avrXa10 ) from seedling to adult stages .
Linkage analysis using existing RFLP markers and F2 mapping population mapped the Xa10 locus to the proximal side of E1981S with genetic distance at 0 . 93 cM .
With five new RFLP markers developed from the genomic sequence of Nipponbare , Xa10 was finely mapped at genetic distance of 0 . 28 cM between proximal marker M491 and distal marker M419 and co-segregated with markers S723 and M604 .
The physical distance between M491 and M419 on Nipponbare genome is 74 kb .
Seven genes have been annotated from this 74-kb region and six of them are possible Xa10 candidates .
The results of this study will be useful in Xa10 cloning and marker-assisted breeding .
| Matching Sentences:
[ Sen. 1, subscore: 1.00 ]: High-resolution genetic mapping of bacterial blight resistance gene Xa10 .
| | Supplemental links/files: reference in endnote online text related articles pubmed citation | |
Score: 1.00 |
|---|
| Title: Pathogen-induced expressional loss of function is the key factor in race-specific bacterial resistance conferred by a recessive R gene xa13 in rice .
| | Author: Yuan M Chu Z Li X Xu C Wang S | | Journal: Plant Cell Physiol Citation: V : 50 P : 947-55 Type: MEDLINE | | Literature: oryza Field: title Doc ID: pub19318375 Accession (PMID): 19318375 | | Abstract: The fully recessive disease resistance ( R ) gene xa13 , which mediates race-specific resistance to Xanthomonas oryzae pv . oryzae ( Xoo ) , encodes a plasma membrane protein that differs by one amino acid from that encoded by its dominant ( susceptible ) allele Xa13 .
The molecular mechanism of xa13-mediated resistance is largely unknown .
Here we show that , compared with its dominant allele , expressional non-reaction of xa13 to Xoo infection , not its protein composition , is the key factor for xa13-mediated resistance .
We used the promoter ( P ( Xa13 ) ) of the dominant Xa13 , which was induced by only the incompatible Xoo strain for xa13 , to regulate xa13 and xa13 ( Leu49 ) ( a natural recessive allele of xa13 ) in the rice line IRBB13 carrying xa13 .
The transgenic plants showed the same level of susceptibility and bacterial growth rate as those of the rice line carrying dominant Xa13 , accompanied by the induced accumulation of xa13 or xa13 ( Leu49 ) proteins .
Constitutive expression of dominant XA13 or different xa13 proteins ( xa13 , xa13 ( Leu49 ) , xa13 ( Ala85 ) or xa13 ( Val184 ) ) in IRBB13 had no effect on Xoo infection in the transgenic plants .
These results suggest that race-specific pathogen-induced Xa13 expression is critical for infection .
Thus , xa13 stands out from other R genes in that its functions in disease resistance are due to only the loss of pathogen-induced transcriptional motivation caused by natural selection .
| Matching Sentences:
[ Sen. 1, subscore: 1.00 ]: Pathogen-induced expressional loss of function is the key factor in race-specific bacterial resistance conferred by a recessive R gene xa13 in rice .
| | Supplemental links/files: reference in endnote online text related articles pubmed citation | |
Score: 1.00 |
|---|
| Title: Rice xa13 recessive resistance to bacterial blight is defeated by induction of the disease susceptibility gene Os-11N3 .
| | Author: Antony G Zhou J Huang S Li T Liu B White F Yang B | | Journal: Plant Cell Citation: V : 22 P : 3864-76 Type: MEDLINE | | Literature: oryza Field: title Doc ID: pub21098734 Accession (PMID): 21098734 | | Abstract: The rice ( Oryza sativa ) gene xa13 is a recessive resistance allele of Os-8N3 , a member of the NODULIN3 ( N3 ) gene family , located on rice chromosome 8 .
Os-8N3 is a susceptibility ( S ) gene for Xanthomonas oryzae pv oryzae , the causal agent of bacterial blight , and the recessive allele is defeated by strains of the pathogen producing any one of the type III effectors AvrXa7 , PthXo2 , or PthXo3 , which are all members of the transcription activator-like ( TAL ) effector family .
Both AvrXa7 and PthXo3 induce the expression of a second member of the N3 gene family , here named Os-11N3 .
Insertional mutagenesis or RNA-mediated silencing of Os-11N3 resulted in plants with loss of susceptibility specifically to strains of X oryzae pv oryzae dependent on AvrXa7 or PthXo3 for virulence .
We further show that AvrXa7 drives expression of Os-11N3 and that AvrXa7 interacts and binds specifically to an effector binding element within the Os-11N3 promoter , lending support to the predictive models for TAL effector binding specificity .
The result indicates that variations in the TAL effector repetitive domains are driven by selection to overcome both dominant and recessive forms of resistance to bacterial blight in rice .
The finding that Os-8N3 and Os-11N3 encode closely related proteins also provides evidence that N3 proteins have a specific function in facilitating bacterial blight disease .
| Matching Sentences:
[ Sen. 1, subscore: 1.00 ]: Rice xa13 recessive resistance to bacterial blight is defeated by induction of the disease susceptibility gene Os-11N3 .
| | Supplemental links/files: reference in endnote online text related articles pubmed citation | |
Score: 1.00 |
|---|
| Title: Characterization of Xanthomonas oryzae-responsive cis-acting element in the promoter of rice race-specific susceptibility gene Xa13 .
| | Author: Yuan T Li X Xiao J Wang S | | Journal: Mol Plant Citation: V : 4 P : 300-9 Type: MEDLINE | | Literature: oryza Field: title Doc ID: pub21208999 Accession (PMID): 21208999 | | Abstract: The rice Xa13 gene , whose promoter harbors a UPT ( up-regulated by transcription activator-like [ TAL ] effector ) box , UPT ( PthXo1 ) , plays a pivotal role in the race-specific pathogenicity caused by Xanthomonas oryzae pv . oryzae ( Xoo ) strain PXO99 .
PXO99 causes rice disease by inducing Xa13 .
It is unknown , however , whether the UPT ( PthXo1 ) box is the only PXO99-responsive cis-regulating elements in the activation of Xa13 expression .
We analyzed the expression of a series of end and site-truncated and site-mutated Xa13 promoters in rice and the binding of PXO99 protein to the intact , partial , or site-mutated UPT ( PthXo1 ) boxes .
In the Xa13 promoter , UPT ( PthXo1 ) box is the only Xoo-responsive cis-acting element that results in PXO99-induced Xa13 expression .
The 5-terminal second , third , and fourth nucleotides of the box are important for bacterial protein binding and gene activation ; mutation of any one of these sites abolished PXO99-induced gene expression .
Furthermore , the 3-half of the UPT ( PthXo1 ) box is also required for protein binding and gene activation .
These findings will enhance our understanding of the molecular mechanism of the interaction of rice and Xoo via UPT boxes and TAL effectors .
| Matching Sentences:
[ Sen. 1, subscore: 1.00 ]: Characterization of Xanthomonas oryzae-responsive cis-acting element in the promoter of rice race-specific susceptibility gene Xa13 .
| | Supplemental links/files: reference in endnote online text related articles pubmed citation | |
Score: 1.00 |
|---|
| Title: Gene silencing using the recessive rice bacterial blight resistance gene xa13 as a new paradigm in plant breeding .
| | Author: Li C Wei J Lin Y Chen H | | Journal: Plant Cell Rep Citation: V : 31 P : 851-62 Type: In-Process | | Literature: oryza Field: title Doc ID: pub22218673 Accession (PMID): 22218673 | | Abstract: Resistant germplasm resources are valuable for developing resistant varieties in agricultural production .
However , recessive resistance genes are usually overlooked in hybrid breeding .
Compared with dominant traits , however , they may confer resistance to different pathogenic races or pest biotypes with different mechanisms of action .
The recessive rice bacterial blight resistance gene xa13 , also involved in pollen development , has been cloned and its resistance mechanism has been recently characterized .
This report describes the conversion of bacterial blight resistance mediated by the recessive xa13 gene into a dominant trait to facilitate its use in a breeding program .
This was achieved by knockdown of the corresponding dominant allele Xa13 in transgenic rice using recently developed artificial microRNA technology .
Tissue-specific promoters were used to exclude most of the expression of artificial microRNA in the anther to ensure that Xa13 functioned normally during pollen development .
A battery of highly bacterial blight resistant transgenic plants with normal seed setting rates were acquired , indicating that highly specific gene silencing had been achieved .
Our success with xa13 provides a paradigm that can be adapted to other recessive resistance genes .
| Matching Sentences:
[ Sen. 1, subscore: 1.00 ]: Gene silencing using the recessive rice bacterial blight resistance gene xa13 as a new paradigm in plant breeding .
| | Supplemental links/files: reference in endnote online text related articles pubmed citation | |
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 Citation: V : 95 ( 4 ) P : 1663-8 Type: ARTICLE | | Literature: oryza Field: title Doc ID: pub9465073 Accession (PMID): 9465073 | | 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. 1, subscore: 1.00 ]: Expression of Xa1 , a bacterial blight-resistance gene in rice , is induced by bacterial inoculation .
| | Supplemental links/files: reference in endnote online text related articles pubmed citation | |
