稻瘟菌MoSRP1作为剪切因子调控致病力和生长发育的机制研究

富含丝氨酸/精氨酸RNA结合蛋白（SRP）是一类在真核细胞中广泛分布但高度分化的蛋白家族，其主要功能是调控前体mRNA中内含子的剪切。许多研究已鉴定了人类、动物和植物中多个SRP结合的RNA基序，并揭示了它们的作用机理，但丝状真菌中SRP作为剪切因子作用的分子机制还未报道。本项目前期研究已确定MoSRP1定位于细胞核，是稻瘟菌致病力与生长发育所必需的，并与一个剪切因子互作。在此基础上，本项目将鉴定MoSRP1特异结合的RNA基序、直接调控的靶标mRNA及其编码蛋白的功能、其它互作蛋白及其参与的剪切过程，解析翻译后修饰对MoSRP1功能的影响和MoSRP1同源蛋白的功能保守性。本项目将揭示MoSRP1作为剪切因子作用的分子机理，也将阐明其调控稻瘟菌致病力与生长发育的分子机制，同时还将有助于理解其它丝状真菌SRP的分子功能。

Serine/arginine-rich RNA binding proteins (SRPs) are a family of proteins that are widely distributed but highly divergent among eukaryotes and function as splicing factors. There have been many studies that identified RNA consensuses bound by individual SRPs and revealed their regulatory roles in pre-mRNA intron splicing in model animals and plants. Filamentous fungi also have two SRPs that are distantly related with SRPs in model animals and plants. However, there has been none study showing how an SRP functions as a splicing factor in filamentous fungi. Previously, we have identified the two SRPs in the rice blast fungus Magnaporthe oryzae and verified that one of them, MoSRP1, is a nuclear protein interacting with a splicing factor and important for the fungal virulence and development. In this project, we will identify RNA consensus bound by MoSRP1, direct mRNA targets and other splicing factors interacting with MoSRP1, and post-translational modifications that are essential to functional MoSRP1, and reveal whether MoSRP1 homologues are functionally conserved among diverse eukaryotes of the same kingdom. Overall, this project will reveal molecular mechanisms of how MoSRP1 functions a splicing factor, with which M. oryzae regulates its virulence, growth, and development, and also provide novel insights into molecular roles of SRP in filamentous fungi.