条斑病菌效应子Tal2b靶向OsF3H03g基因负调控水稻抗病性的分子机理研究

水稻条斑病菌是危害水稻生产的主要致病细菌，目前对其致病因子和靶标基因及其致病机理和信号路径的了解非常有限。将条斑病菌HGA4的效应子Tal2b转入RS105可以显著提高其致病力，说明Tal2b可能是一个重要的毒性因子；通过分析发现Tal2b可能作为转录因子直接调控水稻OsF3H03g基因的表达；利用酵母双杂交系统筛选并验证了OsF3H03g与OsUGT发生特异性互作。本项目拟围绕Tal2b-OsF3H03g-OsUGT之间的互作调控网络开展研究，旨在解析Tal2b如何结合OsF3H03的启动子元件并调控其表达，以及OsF3H03g与OsUGT如何互作协同参与对水杨酸的羟基化和糖基化修饰而导致病害的发生，从而揭示一条全新的病原效应子调控的植物感病信号路径。该研究对于解决目前无有效的水稻抗条斑病基因用于抗病育种具有重要意义，有望通过对条斑病感病基因进行编辑而获得抗病新材料。

Xanthomonas oryzae pv. oryzicola is one of the main pathogenic bacteria that harms rice production, the understanding of its pathogenic factors, target genes, pathogenic mechanism and signal pathway is very limited at present. The transfer of TAL effector Tal2b from HGA4 into RS105 can significantly improve its pathogenicity, indicating that Tal2b may be an important toxic effector; bioinformatics analysis revealed that Tal2b may directly regulate the expression of rice OsF3H03g gene as a transcription factor, and the OsF3H03g interaction protein, OsUGT was screened and confirmed by yeast two-hybrid system. This project intends to study the interaction and regulatory network between Tal2b-OsF3H03g-OsUGT, aiming to analyze how Tal2b binds to the promoter element of OsF3H03g gene and regulates its expression, and how OsF3H03g interact with OsUGT to participate in hydroxylation and glycosacification modification of salicylic acid, thus elucidates a novel signaling pathway of plant susceptibility which regulated by pathogen effectors. This study has important significance for solving the problem of that there is no effective resistance gene of rice bacterial leaf streak for resistance breeding, and it is expected to obtain new resistant materials by modifying the bacterial leaf streak susceptibility gene in rice.