一个与杂种优势相关的小分子RNA OsmiR1432的功能研究

MicroRNAs (miRNAs) are non-coding RNAs and approximately 20-25 nucleotides in length. miRNAs regulate gene expression as a negative regulator and play important roles in plant growth and development. Previous small RNA sequencing results in our lab indicated OsmiR1432 was down-regulated expressed in two superhybrid rices than their parents. The target genes of OsmiR1432 predicted by bioinformatics are the key genes in Ca2+ signal transduction pathway.Our results have shown that OsmiR1432 overexpression transgenic rice displayed weak vigor,drawf and yellow leaves phenotypes and also have verified the splicing site of OsmiR1432.In this stuy,we hope to investigate the function of OsmiR1432 and its target genes by transgenic study,DGE sequencing and bioinformatic analysis to clarify their regulation mechanism in rice growth and development.Moreover,we hope to preliminary explore their role in rice heterosis by reverse genetics and genomics methods to estabilish the link between miRNA,Ca2+ signal transduction and rice hererosis. In addition, function study of OsmiR1432 and its target genes can provide a theoretical basis for the development a new superhybrid rice of high yielding, high quality and resistance and also lay the foundation for applied research about OsmiR1432 and its target genes in agricultural production.

MicroRNAs(miRNAs)是一类长20－25个碱基的小分子RNAs，作为负调控因子在植物生长发育过程中起重要作用。本实验室前期小RNA测序结果表明OsmiR1432在两超级杂交稻中均显著下调表达，预测其靶基因为水稻钙信号转导途径中的关键基因。已有实验结果表明OsmiR1432的超表达转基因水稻出现植株矮化、叶片黄花、生长势变弱等表型。5'RACE已确定OsmiR1432的靶位点。本申请项目拟通过转基因研究、水稻全基因组数字表达谱测序技术和生物信息学分析调查OsmiR1432及其靶基因的功能，阐明其在水稻生长发育中参与的调控网络，从反向遗传学与基因组学的角度初探他们在水稻杂种优势形成中的作用,建立单个miRNA,钙信号转导途径与水稻杂种优势之间的联系，为培育高产、优质、抗逆的新一代超级杂交稻品种提供理论依据，也为OsmiR1432及其靶基因在农业生产上的应用奠定研究基础。