G蛋白信号调控因子调控稻瘟病菌识别寄主表面信号和致病的分子机制研究

Rice blast, caused by Magnaporthe oryzae, is a destructive disease during rice cultivation that severely threatens the production of rice crops worldwide. Heterotrimeric GTP-binding protein (G-protein) is involved in surface recognition, appressorium formation, conidiation, infectious growth, and pathogenicity of M. oryzae. However, the detailed molecular mechanism for the G-protein meditated pathogenesis has yet to be elucidated. Our previous work characterized eight RGS and RGS-like proteins in M. oryzae and found that four MoRgs proteins (MoRgs1, MoRgs3, MoRgs4 and MoRgs7) play pivotal roles in orchestrating surface recognition, appressorium formation and pathogenicity. This project plans to complete the following studies: 1) Identification of MoRgs proteins (MoRgs1, MoRgs3, MoRgs4 and MoRgs7)-interacting proteins and investigation of their roles in MoRgs-mediated surface recognition, appressorium formation and pathogenesis. 2) Identifcation of MoRgs-regulated genes/small RNA and investigation of their roles in MoRgs-mediated surface recognition, appressorium formation and pathogenesis. Our research will ultimately reveal the molecular basis of MoRgs-mediated networks in surface recognition, appressorium formation and pathogenesis of M. oryzae and will implicate the potential for targeting MoRgs-mediated networks for the development of novel fungicides against M. oryzae.

稻瘟病菌引起的稻瘟病是水稻上最重要的毁灭性病害，威胁着全球粮食安全。G蛋白信号途径调控该病菌对寄主的识别，将寄主表面信号整合为病菌胞内信号，进而调控附着胞的形成和病菌的致病性，但是其机制仍不清楚。项目组前期在该病菌中发现8个G蛋白信号调控因子(MoRgs)，其中4个参与病菌对寄主表面信号的识别和致病性。本项目将进一步研究这4个MoRgs调控病菌识别寄主和致病性的分子机制，拟分别鉴定这些MoRgs的互作蛋白和受MoRgs调控的重要基因，研究它们在MoRgs调控稻瘟病菌识别寄主表面信号和致病中的生物学功能与作用机制。研究结果可望阐明MoRgs调控稻瘟病菌识别寄主表面信号和致病的分子机制，拓展对该病菌致病机理及其与寄主水稻互作机制的认识，为以G蛋白信号途径为靶标的药剂开发提供新的靶标。

稻瘟病菌引起的稻瘟病是水稻上最重要的毁灭性病害，威胁着全球水稻生产和粮食安全。G蛋白信号途径调控稻瘟病菌对寄主表面信号的识别，将寄主表面信号整合为病菌胞内信号，进而调控附着胞的形成和病菌的致病性，但是其分子机制仍不清楚。项目组前期在该病菌中发现8个G蛋白信号调控因子(MoRgs)，其中4个参与病菌对寄主表面信号的识别和致病性。本项目在稻瘟病菌中鉴定到一系列受MoRgs蛋白调控的互作蛋白，并深入解析了其调控附着胞形成的机制；进一步鉴定到受MoRgs蛋白调控的关键基因，并揭示了其调控致病力的机制；同时，鉴定到受MoRgs蛋白调控的候选小分子RNA及其靶基因，阐明了其调控附着胞形成和致病力的机制。研究结果揭示MoRgs蛋白调控稻瘟病菌识别寄主表面信号、附着胞形成、生长发育及其致病的分子机制，可望为开发防治稻瘟病的新型药剂提供新的靶标基因。