28 matches found in 22 documents. Search time: 0.706 seconds. |
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Score: 1.00 | Title: Phosphoenolpyruvate carboxylase protein kinase from developing castor oil seeds : partial purification , characterization , and reversible control by photosynthate supply .
| Author: Murmu J Plaxton WC | Journal: Planta Year: 2007 Type: MEDLINE | Literature: oryza Field: abstract Doc ID: pub17624549 Accession (PMID): 17624549 | Abstract: Phosphoenolpyruvate carboxylase ( PEPC , EC 4 . 1 . 1 . 31 ) protein kinase ( PPCK ) was purified approximately 1 , 500-fold from developing castor oil seeds ( COS ) .
Gel filtration and immunoblotting with anti- ( rice PPCK2 ) -immune serum indicated that this Ca2+-insensitive PPCK exists as a 31-kDa monomer .
COS PPCK-mediated rephosphorylation of the 107-kDa subunit ( p107 ) of COS PEPC1 ( Km = 2 . 2 microM ) activated PEPC1 by approximately 80% when assayed under suboptimal conditions ( pH 7 . 3 , 0 . 2 mM PEP , and 0 . 125 mM malate ) .
COS PPCK displayed remarkable selectivity for phosphorylating COS PEPC1 ( relative to tobacco , sorghum , or maize PEPCs ) , exhibited a broad pH-activity optima of approximately pH 8 . 5 , and at pH 7 . 3 was activated 40-65% by 1 mM PEP , or 10 mM Gln or Asn , but inhibited 65% by 10 mM L-malate .
The possible control of COS PPCK by disulfide-dithiol interconversion was suggested by its rapid inactivation and subsequent reactivation when incubated with oxidized glutathione and then dithiothreitol .
In vitro PPCK activity correlated with in vivo p107 phosphorylation status , with both peaking in mid-cotyledon to full-cotyledon developing COS .
Notably , PPCK activity and p107 phosphorylation of developing COS were eliminated following pod excision or prolonged darkness of intact plants .
Both effects were fully reversed 12 h following reillumination of darkened plants .
These results implicate a direct relationship between the up-regulation of COS PPCK and p107 phosphorylation during the recommencement of photosynthate delivery from illuminated leaves to the non-photosynthetic COS .
Overall , the results support the hypothesis that PEPC and PPCK participate in the control of photosynthate partitioning into C-skeletons needed as precursors for key biosynthetic pathways of developing COS .
| Matching Sentences: [ Sen. 1, subscore: 1.00 ]: Phosphoenolpyruvate carboxylase ( PEPC , EC 4 . 1 . 1 . 31 ) protein kinase ( PPCK ) was purified approximately 1 , 500-fold from developing castor oil seeds ( COS ) .
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Score: 1.00 | Title: Divergence of evolutionary ways among common sym genes : CASTOR and CCaMK show functional conservation between two symbiosis systems and constitute the root of a common signaling pathway .
| Author: Banba M Gutjahr C Miyao A Hirochika H Paszkowski U Kouchi H Imaizumi-Anraku H | Journal: Plant Cell Physiol Year: 2008 Type: MEDLINE | Literature: oryza Field: abstract Doc ID: pub18852152 Accession (PMID): 18852152 | Abstract: In recent years a number of legume genes involved in root nodule ( RN ) symbiosis have been identified in the model legumes , Lotus japonicus ( Lotus ) and Medicago truncatula .
Among them , a distinct set of genes has been categorized as a common symbiosis pathway ( CSP ) , because they are also essential for another mutual interaction , the arbuscular mycorrhiza ( AM ) symbiosis , which is evolutionarily older than the RN symbiosis and is widely distributed in the plant kingdom .
Based on the concept that the legume RN symbiosis has evolved from the ancient AM symbiosis , one issue is whether the CSP is functionally conserved between non-nodulating plants , such as rice , and nodulating legumes .
We identified three rice CSP gene orthologs , OsCASTOR , OsPOLLUX and OsCCaMK , and demonstrated the indispensable roles of OsPOLLUX and OsCCaMK in rice AM symbiosis .
Interestingly , molecular transfection of either OsCASTOR or OsCCaMK could fully complement symbiosis defects in the corresponding Lotus mutant lines for both the AM and RN symbioses .
Our results not only provide a conserved genetic basis for the AM symbiosis between rice and Lotus , but also indicate that the core of the CSP has been well conserved during the evolution of RN symbiosis .
Through evolution , CASTOR and CCaMK have remained as the molecular basis for the maintenance of CSP functions in the two symbiosis systems .
| Matching Sentences: [ Sen. 7, subscore: 1.00 ]: Through evolution , CASTOR and CCaMK have remained as the molecular basis for the maintenance of CSP functions in the two symbiosis systems .
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Score: 2.00 | Title: Antiquity and function of CASTOR and POLLUX , the twin ion channel-encoding genes key to the evolution of root symbioses in plants .
| Author: Chen C Fan C Gao M Zhu H | Journal: Plant Physiol Year: 2009 Type: MEDLINE | Literature: oryza Field: abstract Doc ID: pub18978069 Accession (PMID): 18978069 | Abstract: Root symbioses with arbuscular mycorrhizal fungi and rhizobial bacteria share a common signaling pathway in legumes .
Among the common symbiosis genes are CASTOR and POLLUX , the twin homologous genes in Lotus japonicus that encode putative ion channel proteins .
Here , we show that the orthologs of CASTOR and POLLUX are ubiquitously present and highly conserved in both legumes and nonlegumes .
Using rice ( Oryza sativa ) as a study system , we employ reverse genetic tools ( knockout mutants and RNA interference ) to demonstrate that Os-CASTOR and Os-POLLUX are indispensable for mycorrhizal symbiosis in rice .
Furthermore , a cross-species complementation test indicates that Os-POLLUX can restore nodulation , but not rhizobial infection , to a Medicago truncatula dmi1 mutant .
| Matching Sentences: [ Sen. 2, subscore: 1.00 ]: Among the common symbiosis genes are CASTOR and POLLUX , the twin homologous genes in Lotus japonicus that encode putative ion channel proteins . [ Sen. 3, subscore: 1.00 ]: Here , we show that the orthologs of CASTOR and POLLUX are ubiquitously present and highly conserved in both legumes and nonlegumes .
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Score: 1.00 | Title: Arbuscular mycorrhiza-specific signaling in rice transcends the common symbiosis signaling pathway .
| Author: Gutjahr C Banba M Croset V An K Miyao A An G Hirochika H Imaizumi-Anraku H Paszkowski U | Journal: Plant Cell Year: 2008 Type: In-Data-Review | Literature: oryza Field: abstract Doc ID: pub19033527 Accession (PMID): 19033527 | Abstract: Knowledge about signaling in arbuscular mycorrhizal ( AM ) symbioses is currently restricted to the common symbiosis ( SYM ) signaling pathway discovered in legumes .
This pathway includes calcium as a second messenger and regulates both AM and rhizobial symbioses .
Both monocotyledons and dicotyledons form symbiotic associations with AM fungi , and although they differ markedly in the organization of their root systems , the morphology of colonization is similar .
To identify and dissect AM-specific signaling in rice ( Oryza sativa ) , we developed molecular phenotyping tools based on gene expression patterns that monitor various steps of AM colonization .
These tools were used to distinguish common SYM-dependent and -independent signaling by examining rice mutants of selected putative legume signaling orthologs predicted to be perturbed both upstream ( CASTOR and POLLUX ) and downstream ( CCAMK and CYCLOPS ) of the central , calcium-spiking signal All four mutants displayed impaired AM interactions and altered AM-specific gene expression patterns , therefore demonstrating functional conservation of SYM signaling between distant plant species .
In addition , differential gene expression patterns in the mutants provided evidence for AM-specific but SYM-independent signaling in rice and furthermore for unexpected deviations from the SYM pathway downstream of calcium spiking .
| Matching Sentences: [ Sen. 5, subscore: 1.00 ]: These tools were used to distinguish common SYM-dependent and -independent signaling by examining rice mutants of selected putative legume signaling orthologs predicted to be perturbed both upstream ( CASTOR and POLLUX ) and downstream ( CCAMK and CYCLOPS ) of the central , calcium-spiking signal All four mutants displayed impaired AM interactions and altered AM-specific gene expression patterns , therefore demonstrating functional conservation of SYM signaling between distant plant species .
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Score: 1.00 | Title: Deacidification of high free fatty acid-containing rice bran oil by non-conventional reesterification process .
| Author: Singh S Singh RP | Journal: J Oleo Sci Year: 2009 Type: MEDLINE | Literature: oryza Field: abstract Doc ID: pub19145058 Accession (PMID): 19145058 | Abstract: Rice bran ( Oryza sativa ) oil is known for containing higher amount of free fatty acid ( FFA ) generated by hydrolytic enzyme .
This FFA causes heavy neutral oil losses due to saponification and emulsification since it produces large amount of soap in the conventional alkali refining process .
In the present study the FFA of degummed rice bran oil ( RBO ) was significantly reduced by reesterifying it with glycerol .
The reesterification process was carried out by varying the temperature and amount of excess glycerol using 0 . 2% catalyst ( SnCl ( 2 ) ) .
The maximum efficiency of the process could be attained at 200 degrees C using 70% excess glycerol and the maximum reduction in acid value ( from 24 . 3 to 3 . 0 ) of RBO was observed within 4 h .
The reesterified RBO was used to prepare stand oil and varnish and their performance characteristics were compared with those of the products obtained from dehydrated castor oil ( DCO ) .
| Matching Sentences: [ Sen. 6, subscore: 1.00 ]: The reesterified RBO was used to prepare stand oil and varnish and their performance characteristics were compared with those of the products obtained from dehydrated castor oil ( DCO ) .
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