线粒体病毒SsMV1引起植物病原真菌核盘菌致病力衰退的分子机理研究

Sclerotinia sclerotiorum is a destructive phytopathogenic fungus. This fungus causes Sclerotinia disease and is responsible for serious yield losses of many oil and horticultural crops. S. sclerotiorum-resistant crop varieties are still unavailable now. Mitovirus are a group of viruses replicating in mitochondria of host cell, and currently are only found in fungi. Our previous study showed that the mitovirus SsMV1 can cause hypovirulence of S. sclerotiorum, providing the opportunity to study on the pathogenic mechanisms associated with mitochondria of S. sclerotiorum. In this proposal, serial experiments were designed to decipher the molecular mechanism of hypovirulence of S. sclerotiorum via SsMV1-S.sclerotiorum interaction system. Firstly, through comparing the differences of the mitochondrial structure and function between hypovirulent and virulent strains, we could clarify the effect of SsMV1 on mitochondria of S. sclerotiorum. Secondly, based on high-throughput transcriptome sequencing analysis, comparative transcriptomic approach will be applied to characterize the differentially expressed genes (DEGs) between hypovirulent and virulent strains, as well as screen for the genes associated with mitochondrial morphogenesis and forming. Thirdly, with RNAi silence and over-expression technique, we will further study the DEGs function on hyphal growth, sclerotial formation and virulence. The novel pathogenicity-related genes will be identified. Our study is likely to help us analyzing the function of mitochondria in the pathogenesis process of S. sclerotiorum; it also may lead to the discovery of new clues for the control of S. sclerotiorum. Furthermore, our study will provide important insights in the interaction between mitoviruses and fungi.

核盘菌引起的菌核病是多种油料及园艺作物的重要真菌病害，生产上缺乏抗病品种。线粒体病毒（mitovirus）是在线粒体中复制的病毒，目前只在真菌中有发现。申请者在前期研究中发现一种可引起核盘菌衰退的线粒体病毒（SsMV1），为从线粒体角度研究核盘菌致病机理提供了契机。本申请项目拟在前期研究基础上，以SsMV1为材料从线粒体视角开展核盘菌致病力衰退的分子机理研究。通过分析感染SsMV1前后核盘菌菌株的线粒体结构及其功能差异，明确SsMV1对核盘菌线粒体的影响；采用RNA-seq技术分析SsMV1引起寄主的基因表达差异，筛选获得与线粒体形态发生及形成相关的基因，应用基因沉默或超量表达等技术鉴定出核盘菌新的致病相关基因。本项目的完成不仅可以解析线粒体在致病过程中的功能、为菌核病防治研究提供新的线索与依据，同时也将为阐述线粒体病毒与真菌互作提供重要参考。

核盘菌是一种世界性的重要植物病原真菌。线粒体病毒（mitovirus）是在线粒体中复制的病毒。前期研究发现线粒体病毒（SsMV1）的侵染可以引起核盘菌出现衰退症状，这为从线粒体角度研究核盘菌致病机理提供了契机。本申请项目拟在前期研究基础上，以SsMV1为材料从线粒体视角开展核盘菌致病力衰退的分子机理研究。通过分析感染SsMV1前后核盘菌菌株的线粒体结构及其功能差异，明确了SsMV1对核盘菌线粒体的影响；采用RNA-seq技术分析了SsMV1引起寄主的基因表达差异，对与线粒体自噬通路相关的基因进行了初筛，并应用基因敲除技术尝试敲除验证。此外，从偶然发现的一株患病油菜菌株中分离和鉴定出非检疫性油菜黑胫病菌，并从中分离和克隆了一例新的线粒体病毒（LbMV1）。本项目的完成不仅可以解析线粒体在致病过程中的功能、为菌核病防治研究提供新的线索与依据，同时也将为阐述线粒体病毒与真菌互作提供重要参考。