| 16 matches found in 8 documents. Search time: 2.261 seconds. |
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Score: 7.00 |
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| Title: Independent Losses of Function in a Polyphenol Oxidase in Rice : Differentiation in Grain Discoloration between Subspecies and the Role of Positive Selection under Domestication .
| | Author: Yu Y Tang T Qian Q Wang Y Yan M Zeng D Han B Wu CI Shi S Li J | | Journal: Plant Cell Citation: V : 20 P : 2946-59 Year: 2008 Type: In-Data-Review | | Literature: oryza Field: abstract Doc ID: pub19033526 Accession (PMID): 19033526 | | Abstract: Asian rice ( Oryza sativa ) cultivars originated from wild rice and can be divided into two subspecies by several criteria , one of which is the phenol reaction ( PHR ) phenotype .
Grains of indica cultivars turn brown in a phenol solution that accelerates a similar process that occurs during prolonged storage .
By contrast , the grains of japonica do not discolor .
This distinction may reflect the divergent domestication of these two subspecies .
The PHR is controlled by a single gene , Phr1 ; here , we report the cloning of Phr1 , which encodes a polyphenol oxidase .
The Phr1 gene is indeed responsible for the PHR phenotype , as transformation with a functional Phr1 can complement a PHR negative cultivar .
Phr1 is defective in all japonica lines but functional in nearly all indica and wild strains .
Phylogenetic analysis showed that the defects in Phr1 arose independently three times .
The multiple recent origins and rapid spread of phr1 in japonica suggest the action of positive selection , which is further supported by several population genetic tests .
This case may hence represent an example of artificial selection driving the differentiation among domesticated varieties .
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[ Sen. 5, subscore: 2.00 ]: The PHR is controlled by a single gene , Phr1 ; here , we report the cloning of Phr1 , which encodes a polyphenol oxidase .
[ Sen. 6, subscore: 2.00 ]: The Phr1 gene is indeed responsible for the PHR phenotype , as transformation with a functional Phr1 can complement a PHR negative cultivar .
[ Sen. 7, subscore: 1.00 ]: Phr1 is defective in all japonica lines but functional in nearly all indica and wild strains .
[ Sen. 8, subscore: 1.00 ]: Phylogenetic analysis showed that the defects in Phr1 arose independently three times .
[ Sen. 9, subscore: 1.00 ]: The multiple recent origins and rapid spread of phr1 in japonica suggest the action of positive selection , which is further supported by several population genetic tests .
| | Supplemental links/files: reference in endnote online text related articles pubmed citation | |
Score: 4.00 |
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| Title: Novel Phr1 mutations and the evolution of phenol reaction variation in US weedy rice ( Oryza sativa ) .
| | Author: Gross BL Skare KJ Olsen KM | | Journal: New Phytol Citation: V : 184 P : 842-50 Year: 2009 Type: In-Process | | Literature: oryza Field: abstract Doc ID: pub19674331 Accession (PMID): 19674331 | | Abstract: *Red rice , a major agricultural weed , is phenotypically diverse and possesses traits that are similar to both wild and cultivated rice .
The genetic resources available for rice make it possible to examine the molecular basis and evolution of traits characterizing this weed .
Here , we assess the phenol reaction - a classical trait for distinguishing among cultivated rice varieties - in red rice at the phenotypic and molecular levels .
*We phenotyped more than 100 US weed samples for the phenol reaction and sequenced the underlying Phr1 locus in a subset of samples .
Data were analyzed in combination with previously published Phr1 data for cultivated rice .
*Most weed accessions ( 96 . 3% ) are positive for the phenol reaction , and samples with a negative response carry loss-of-function alleles that are rare or heretofore undocumented .
One such allele may have evolved through mutational convergence of a 1-bp frameshift insertion .
Haplotype sharing between red rice and US cultivars suggests occasional crop-weed hybridization .
*Our discovery of previously undocumented nonfunctional phr1 alleles suggests that there are likely to be other loss-of-function mutations segregating in Oryza sativa around the world .
Red rice may provide a useful study system for understanding the adaptive significance of Phr1 variation in agricultural settings .
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[ Sen. 4, subscore: 1.00 ]: *We phenotyped more than 100 US weed samples for the phenol reaction and sequenced the underlying Phr1 locus in a subset of samples .
[ Sen. 5, subscore: 1.00 ]: Data were analyzed in combination with previously published Phr1 data for cultivated rice .
[ Sen. 9, subscore: 1.00 ]: *Our discovery of previously undocumented nonfunctional phr1 alleles suggests that there are likely to be other loss-of-function mutations segregating in Oryza sativa around the world .
[ Sen. 10, subscore: 1.00 ]: Red rice may provide a useful study system for understanding the adaptive significance of Phr1 variation in agricultural settings .
| | Supplemental links/files: reference in endnote online text related articles pubmed citation | |
Score: 3.00 |
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| Title: PHO2 , microRNA399 , and PHR1 define a phosphate-signaling pathway in plants .
| | Author: Bari R Datt Pant B Stitt M Scheible WR .
| | Journal: Plant Physiol .
Citation: V : 141 ( 3 ) P : 988-99 Year: 2006 Type: ARTICLE | | Literature: oryza Field: abstract Doc ID: pub16679424 Accession (PMID): 16679424 | | Abstract: Inorganic phosphate ( Pi ) -signaling pathways in plants are still largely unknown .
The Arabidopsis ( Arabidopsis thaliana ) pho2 mutant overaccumulates Pi in leaves in Pi-replete conditions .
Micrografting revealed that a pho2 root genotype is sufficient to yield leaf Pi accumulation .
In pho2 mutants , Pi does not repress a set of Pi starvation-induced genes , including AtIPS1 , AT4 , and Pi transporters Pht1 ; 8 and Pht1 ; 9 .
Map-based cloning identified PHO2 as At2g33770 , an unusual E2 conjugase gene .
It was recently shown that Pi deprivation induces mature microRNA ( miRNA [ miR399 ] ) and that overexpression of miR399 in Pi-replete conditions represses E2 conjugase expression and leads to high leaf Pi concentrations , thus phenocopying pho2 .
We show here that miR399 primary transcripts are also strongly induced by low Pi and rapidly repressed after addition of Pi .
PHO2 transcripts change reciprocally to miR399 transcripts in Pi-deprived plants and in miR399 overexpressers .
However , responses after Pi readdition and in beta-glucuronidase reporter lines suggest that PHO2 expression is also regulated by Pi in a manner unrelated to miR399-mediated transcript cleavage .
Expression of miR399 was strongly reduced in Pi-deprived Arabidopsis phr1 mutants , and a subset of Pi-responsive genes repressed in Pi-deprived phr1 mutants was up-regulated in Pi-replete pho2 mutants .
This places miR399 and PHO2 in a branch of the Pi-signaling network downstream of PHR1 .
Finally , putative PHO2 orthologs containing five miR399-binding sites in their 5-untranslated regions were identified in other higher plants , and Pi-dependent miR399 expression was demonstrated in rice ( Oryza sativa ) , suggesting a conserved regulatory mechanism . | Matching Sentences:
[ Sen. 10, subscore: 2.00 ]: Expression of miR399 was strongly reduced in Pi-deprived Arabidopsis phr1 mutants , and a subset of Pi-responsive genes repressed in Pi-deprived phr1 mutants was up-regulated in Pi-replete pho2 mutants .
[ Sen. 11, subscore: 1.00 ]: This places miR399 and PHO2 in a branch of the Pi-signaling network downstream of PHR1 .
| | Supplemental links/files: reference in endnote online text related articles pubmed citation | |
Score: 1.00 |
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| Title: Cloning and characterization of the BLR2 , the homologue of the blue-light regulator of Neurospora crassa WC-2 , in the phytopathogenic fungus Bipolaris oryzae .
| | Author: Moriwaki A Katsube H Ueno M Arase S Kihara J | | Journal: Curr Microbiol Citation: V : 56 P : 115-21 Year: 2008 Type: MEDLINE | | Literature: oryza Field: abstract Doc ID: pub18172720 Accession (PMID): 18172720 | | Abstract: Bipolaris oryzae is a filamentous ascomycetous fungus that causes brown leaf spot disease in rice .
We isolated and characterized BLR2 , a gene that encodes a putative blue-light regulator similar to Neurospora crassa white collar-2 ( WC-2 ) .
The deduced amino acid sequence of the BLR2 showed significant homology to other fungal blue-light regulator proteins in the Per-Arnt-Sim ( PAS ) protein-protein interaction domain , nuclear localization signal , and GATA zinc finger DNA-binding domains .
The BLR2-silenced transformants hardly produced conidia in the subsequent dark condition after near-ultraviolet ( NUV ) irradiation .
Furthermore , the BLR2-silenced transformants suppressed the photolyase ( PHR1 ) gene expression enhanced by NUV irradiation .
These results indicate that BLR2 is necessary not only for conidial formation , but also for NUV radiation-enhanced photolyase gene expression in B oryzae .
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[ Sen. 5, subscore: 1.00 ]: Furthermore , the BLR2-silenced transformants suppressed the photolyase ( PHR1 ) gene expression enhanced by NUV irradiation .
| | Supplemental links/files: reference in endnote online text related articles pubmed citation | |
Score: 1.00 |
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| Title: Comprehensive sequence and whole-life-cycle expression profile analysis of the phosphate transporter gene family in rice .
| | Author: Liu F Chang XJ Ye Y Xie WB Wu P Lian XM | | Journal: Mol Plant Citation: V : 4 P : 1105-22 Year: 2011 Type: In-Process | | Literature: oryza Field: abstract Doc ID: pub21832284 Accession (PMID): 21832284 | | Abstract: Plant phosphate transporter ( PT ) genes comprise a large family with important roles in various physiological and biochemical processes .
In this study , a database search yielded 26 potential PT family genes in rice ( Oryza sativa ) .
Analysis of these genes led to identification of eight conserved motifs and 5-12 trans-membrane segments , most of them conserved .
A total of 237 putative cis elements were found in the 2-kb upstream region of these genes .
Of these , a majority were Pi-response and other stress-related cis regulatory elements , such as PHO-like , TATA-box-like , PHR1 , or Helix-loop-helix elements , and WRKY1 and ABRE elements , suggesting gene regulation by these signals .
Comprehensive expression analysis of these genes was performed using data from microarrays hybridized with RNA from 27 it issues covering the entire lifecycle from three rice genotypes : Minghui 63 , Zhenshan 97 , and Shanyou 63 .
Real-time PCR analysis confirmed that three rice PT genes are preferentially expressed in stamen at 1 d before flowering , two in panicle at the heading stage , and two in flag leaf at 14 d after the heading stage .
Hormone-treatment experiments revealed differential up-regulation or down-regulation of 11 rice PT genes in seedlings exposed to five hormones , respectively .
These results will be useful for elucidating the roles of these genes in the growth , development , and stress response of the rice plant .
| Matching Sentences:
[ Sen. 5, subscore: 1.00 ]: Of these , a majority were Pi-response and other stress-related cis regulatory elements , such as PHO-like , TATA-box-like , PHR1 , or Helix-loop-helix elements , and WRKY1 and ABRE elements , suggesting gene regulation by these signals .
| | Supplemental links/files: reference in endnote online text related articles pubmed citation | |
