Heterosis is a biological phenomenon whereby the offspring from two parents show improved and superior performance than either inbred parental lines. Hybrid rice is one of the most successful apotheoses in crops utili...Heterosis is a biological phenomenon whereby the offspring from two parents show improved and superior performance than either inbred parental lines. Hybrid rice is one of the most successful apotheoses in crops utilizing heterosis. Transcriptional profiling of F1 super-hybrid rice Liangyou-2186 and its parents by serial analysis of gene expression （SAGE） revealed 1183 differentially expressed genes （DGs）, among which DGs were found significantly enriched in pathways such as photosynthesis and carbon-fixation, and most of the key genes involved in the carbon-fixation pathway exhibited up-regulated expression in F1 hybrid rice. Moreover, increased catabolic activity of corresponding enzymes and photosynthetic efficiency were also detected, which combined to indicate that carbon fixation is enhanced in F1 hybrid, and might probably be associated with the yield vigor and heterosis in super-hybrid rice. By correlating DGs with yield-related quantitative trait loci （QTL）, a potential relationship between differential gene expression and phenotypic changes was also found. In addition, a regulatory network involving circadian-rhythms and light signaling pathways was also found, as previously reported in Arabidopsis, which suggest that such a network might also be related with heterosis in hybrid rice. Altogether, the present study provides another view for understanding the molecular mechanism underlying heterosis in rice.展开更多
Two sucrose transporter （SUT） cDNAs, OsSUT2M and OsSUT5Z, were isolated from rice （Oryza sativa L.） by reverse transcription polymerase chain reaction （RT-PCR）. Sequencing results indicate they are 1 531 bp and ...Two sucrose transporter （SUT） cDNAs, OsSUT2M and OsSUT5Z, were isolated from rice （Oryza sativa L.） by reverse transcription polymerase chain reaction （RT-PCR）. Sequencing results indicate they are 1 531 bp and 1 635 bp in length including complete open reading frame 1 506bp and 1 608 bp, which encode 502 amino acids and 536 amino acids, respectively. The TopPred program suggested that both sucrose transporter proteins, OsSUT2M and OsSUT5Z, consist of potentially 12 transmembrane domains. Semi-quantitative RT-PCR was carried out to investigate the gene expression patterns of OsSUT2M and OsSUT5Z. In vegetative organs, transcripts of OsSUT2M were higher in source leaf blades than in other organs at the same development stage, whereas transcripts of OsSUT5Z were less traceable in all organs investigated. In reproductive organs, both transcripts of these two genes were high in panicles from the booting stage to 7 days after flowering （DAF） and then sharply declined. The potential physiology functions of these two sucrose transporters are discussed.展开更多
文摘Heterosis is a biological phenomenon whereby the offspring from two parents show improved and superior performance than either inbred parental lines. Hybrid rice is one of the most successful apotheoses in crops utilizing heterosis. Transcriptional profiling of F1 super-hybrid rice Liangyou-2186 and its parents by serial analysis of gene expression （SAGE） revealed 1183 differentially expressed genes （DGs）, among which DGs were found significantly enriched in pathways such as photosynthesis and carbon-fixation, and most of the key genes involved in the carbon-fixation pathway exhibited up-regulated expression in F1 hybrid rice. Moreover, increased catabolic activity of corresponding enzymes and photosynthetic efficiency were also detected, which combined to indicate that carbon fixation is enhanced in F1 hybrid, and might probably be associated with the yield vigor and heterosis in super-hybrid rice. By correlating DGs with yield-related quantitative trait loci （QTL）, a potential relationship between differential gene expression and phenotypic changes was also found. In addition, a regulatory network involving circadian-rhythms and light signaling pathways was also found, as previously reported in Arabidopsis, which suggest that such a network might also be related with heterosis in hybrid rice. Altogether, the present study provides another view for understanding the molecular mechanism underlying heterosis in rice.
基金Supported by the State Key Basic Research and Development Plan of China (2004CB720406)Innovation Foundation of the Chinese Academy of Sciences (KSCXZ-SW-306 and KSCX-SW-03)+1 种基金Program Strategic Scientific Alliances (KNAW-PSA, 04-PSA-BD-04 for P.B.F.O.)the China Exchange Program (KNAW-CEP, 04CDp022 for Y.X.) between China and The Netherlands.
文摘Two sucrose transporter （SUT） cDNAs, OsSUT2M and OsSUT5Z, were isolated from rice （Oryza sativa L.） by reverse transcription polymerase chain reaction （RT-PCR）. Sequencing results indicate they are 1 531 bp and 1 635 bp in length including complete open reading frame 1 506bp and 1 608 bp, which encode 502 amino acids and 536 amino acids, respectively. The TopPred program suggested that both sucrose transporter proteins, OsSUT2M and OsSUT5Z, consist of potentially 12 transmembrane domains. Semi-quantitative RT-PCR was carried out to investigate the gene expression patterns of OsSUT2M and OsSUT5Z. In vegetative organs, transcripts of OsSUT2M were higher in source leaf blades than in other organs at the same development stage, whereas transcripts of OsSUT5Z were less traceable in all organs investigated. In reproductive organs, both transcripts of these two genes were high in panicles from the booting stage to 7 days after flowering （DAF） and then sharply declined. The potential physiology functions of these two sucrose transporters are discussed.
