To understand the regulation system of nitrogen X-starvation in higher plants, a cDNA library from N-starved rice (Oryza sativa L.) seedlings was constructed using rapid subtraction hybridization (RaSH) procedure. Thr...To understand the regulation system of nitrogen X-starvation in higher plants, a cDNA library from N-starved rice (Oryza sativa L.) seedlings was constructed using rapid subtraction hybridization (RaSH) procedure. Through reverse Northern analysis and Northern blotting, 18 unique known genes and two unique unknown genes were identified, which were up-regulated by N-starvation in rice. The known genes are involved in several metabolisms including carbon metabolism, secondary metabolite synthesis, ubiquitylation and protein degradation, phytohormone metabolism, signal transduction, growth regulator and transcription factors. Different induced expression patterns based on spatial and temporal express ions were found for these genes. The results indicate the cross-talks between N-starvation response and various metabolisms in plants.展开更多
Aluminum (Al) toxicity is the major factor limiting crop productivity in acid soils. In this study, a recombinant inbreed line (RIL) population derived from a cross between an Al sensitive lowland indica rice variety...Aluminum (Al) toxicity is the major factor limiting crop productivity in acid soils. In this study, a recombinant inbreed line (RIL) population derived from a cross between an Al sensitive lowland indica rice variety IR1552 and an Al tolerant upland japonica rice variety Azucena, was used for mapping quantitative trait loci (QTLs) for Al tolerance. Three QTLs for relative root length (RRL) were detected on chromosome 1, 9, 12, respectively, and 1 QTL for root length under Al stress is identical on chromosome 1 after one week and two weeks stress. Comparison of QTLs on chromosome 1 from different studies indicated an identical interval between C86 and RZ801 with gene(s) for Al tolerance. This interval provides an important start point for isolating genes responsible for Al tolerance and understanding the genetic nature of Al tolerance in rice. Four Al induced ESTs located in this interval were screened by reverse Northern analysis and confirmed by Northern analysis. They would be candidate genes for the QTL.展开更多
Plastids of nongreen tissues import carbon as a source of biosynthetic pathways and energy, and glucose 6 phosphate is the preferred hexose phosphate taken up by nongreen plastids. A cDNA clone encoding glucose 6 ph...Plastids of nongreen tissues import carbon as a source of biosynthetic pathways and energy, and glucose 6 phosphate is the preferred hexose phosphate taken up by nongreen plastids. A cDNA clone encoding glucose 6 phosphate/phosphate translocator ( GPT ) was isolated from a cDNA library of immature seeds of rice and named as OsGPT . The cDNA has one uninterrupted open reading frame encoding a 42 kDa polypeptide possessing transit peptide consisting of 70 amino acid residues. The OsGPT gene maps on chromosome 8 of rice and is linked to the quantitative trait locus for 1000 grain weight. The expression of OsGPT is mainly restricted to heterotrophic tissues. These results suggest that glucose 6 phosphate imported via GPT can be used for starch biosynthesis in rice nongreen plastids.展开更多
文摘To understand the regulation system of nitrogen X-starvation in higher plants, a cDNA library from N-starved rice (Oryza sativa L.) seedlings was constructed using rapid subtraction hybridization (RaSH) procedure. Through reverse Northern analysis and Northern blotting, 18 unique known genes and two unique unknown genes were identified, which were up-regulated by N-starvation in rice. The known genes are involved in several metabolisms including carbon metabolism, secondary metabolite synthesis, ubiquitylation and protein degradation, phytohormone metabolism, signal transduction, growth regulator and transcription factors. Different induced expression patterns based on spatial and temporal express ions were found for these genes. The results indicate the cross-talks between N-starvation response and various metabolisms in plants.
基金Project (No. 30070070) supported by the National NaturalScience Foundation of China
文摘Aluminum (Al) toxicity is the major factor limiting crop productivity in acid soils. In this study, a recombinant inbreed line (RIL) population derived from a cross between an Al sensitive lowland indica rice variety IR1552 and an Al tolerant upland japonica rice variety Azucena, was used for mapping quantitative trait loci (QTLs) for Al tolerance. Three QTLs for relative root length (RRL) were detected on chromosome 1, 9, 12, respectively, and 1 QTL for root length under Al stress is identical on chromosome 1 after one week and two weeks stress. Comparison of QTLs on chromosome 1 from different studies indicated an identical interval between C86 and RZ801 with gene(s) for Al tolerance. This interval provides an important start point for isolating genes responsible for Al tolerance and understanding the genetic nature of Al tolerance in rice. Four Al induced ESTs located in this interval were screened by reverse Northern analysis and confirmed by Northern analysis. They would be candidate genes for the QTL.
文摘Plastids of nongreen tissues import carbon as a source of biosynthetic pathways and energy, and glucose 6 phosphate is the preferred hexose phosphate taken up by nongreen plastids. A cDNA clone encoding glucose 6 phosphate/phosphate translocator ( GPT ) was isolated from a cDNA library of immature seeds of rice and named as OsGPT . The cDNA has one uninterrupted open reading frame encoding a 42 kDa polypeptide possessing transit peptide consisting of 70 amino acid residues. The OsGPT gene maps on chromosome 8 of rice and is linked to the quantitative trait locus for 1000 grain weight. The expression of OsGPT is mainly restricted to heterotrophic tissues. These results suggest that glucose 6 phosphate imported via GPT can be used for starch biosynthesis in rice nongreen plastids.
基金supported by National High Technology Research and Development Program of China(Grant No.2007AA021504)MOST of China(973 program 2011CB808600)the National Natural Science Foundation of China(Grant No.20872059 and 21072091)
