大豆疫霉效应分子PSR1抑制宿主基因沉默的分子机理研究

大豆疫霉引起的大豆根茎腐病是威胁全世界大豆生产的毁灭性病害之一，每年导致全球十几亿美元的直接经济损失。近来研究发现，RNA沉默也是大豆抗疫霉根腐病的重要防御途径，但是大豆疫霉抑制寄主基因沉默的分子互作机理尚不清楚。在前期工作中，我们利用免疫沉淀和酵母双杂交技术发现大豆疫霉RNA沉默抑制子PSR1与小RNA生成途径关键因子NOT2a/b蛋白互作。本项目计划以大豆GmNOT2基因作为研究对象，通过GmNOT2s与PSR1互作机理研究，明确大豆疫霉对内源小RNA生成的影响；阐述GmNOT2s在小RNA生成途径作用和大豆根腐病抗性中的协同作用模式；解析小RNA介导的抗大豆疫霉根腐病的作用机制，为全面系统探索大豆疫霉致病机理和根腐病的综合防控及抗病品种的培育提供理论依据和技术支撑。

Phytophthora root and stem rot (PRSR)，caused by oomycete pathogen Phytophthora sojae (P.Sojae), is one of the most destructive diseases to world soybean production, and causes millions of dollars of losses annually. RNA silencing is a novel mechanism of gene regulation with important anti-Phytophthora roles in plants. But the interactions between host silencing machinery and Phytophthora effectors remain poorly understood. Our previous results showed that PSR1 directly binds NOT2a/b by immunoprecipitation (IP) and yeast two hybrid (Y2H). In this proposal, our research focus the interactions between GmNOT2s and PSR1, and we will determine the role of small RNAs in regulating soybean defense in response to infection by P. sojae; then examine the roles of GmNOT2 in regulating the biogenesis of endogenous small RNA and development of soybean; and propose the mode of coordination among GmNOT2s in PRSR resistance; explore the molecular mechanism of sRNA mediated resistance to PRSR, our objective is to fully understand the pathogenic mechanism of oomycete pathogens effectors. Success of this project will pave the way for developing new strategy for PRSR disease control, and accelerate the development of P. sojae - resistance new soybean cultivars.