植物miRNAs介导种子成熟调控机制研究

种子成熟是种子贮藏物质积累的阶段，是决定种子质量和产量的关键时期。miRNA是调控基因表达的关键因子，然而目前关于miRNA调控种子成熟机制方面研究还鲜为报道。申请人前期工作阐释了miRNA166介导PHB调控LEC2的种子成熟机制，并建立了一套筛选参与种子成熟调控miRNA的检测体系。本项目将1）以种子发育miRNA组学数据为参考，利用这套检测体系对拟南芥中参与种子成熟调控的miRNAs进行系统的筛选和鉴定；2）通过分子、遗传、高通量测序以及生物信息学等技术手段鉴定miRNA介导的种子成熟调控途径中的关键因子，阐释miRNA调控种子成熟的作用机制；3）整合多个miRNAs的调控途径，构建miRNA调控种子成熟的网络；4）以拟南芥中miRNAs调控种子成熟的机制为模式，探索大豆miRNAs调控种子成熟的作用机制。本项目的实施将对种子质量的改善和产量的提高具有重要的生物学意义和农业实践意义。

Seed maturation is a crucial seed developmental phase during which seed storage reserves are synthesized and accumulated. Understanding the control of seed maturation is thus important for improving seed quality and yield. miRNAs play a central role in the network regulating gene expression as a key regulator; however, miRNA-mediated mechanisms controlling seed maturation are poorly understood. Our previous study demonstrated that miRNA166-mediated regulation of PHB/PHV is responsible for controlling seed maturation, by directly targeting LEC2. Meanwhile, a screening-assay system was developed to identify the seed maturation-related miRNAs. The proposed study will utilize our assay system to screen and identify the seed maturation-related miRNAs based on the miRANome data from developing seed. Subsequently, we will investigate how each identified miRNA might be implicated in governing seed maturation by approaches combining molecular, genetic techniques and second-generation sequencing as well as bioinformatics. Furthermore, the integration of mutiple pathways eventurallly build the Arabidopsis miRNA-mediated regulatory network governing seed maturation. Finally, the soybean miRNA-mediated mechanisms governing seed maturation will be explored on the basis of the results from Arabidopsis. Completion of the current study will provide new and much-needed knowledge for the improvement of seed quality and yield.