黄单胞菌侵染水稻造成的白叶枯病是水稻最主要的细菌性病害之一。水稻黄单胞菌分泌的转录激活子样（transcription activator-like/TAL）和非转录激活子样（non-TAL）效应子对致病性至关重要，然而对non-TAL效应子致病机理的了解十分欠缺。前期研究发现水稻黄单胞菌non-TAL效应子XOO499A在植物中表达能够抑制免疫反应，并且两个同源的受体类似激酶OsRLK1和OsRLK2分别与XOO499A在水稻细胞中形成蛋白复合体。本项目将解析XOO499A与OsRLK1/OsRLK2互作的分子机理，分离和鉴定XOO499A在植物中的其他靶标，研究OsRLK1/OsRLK2以及其他靶标在水稻抗病性中的功能，阐明XOO499A操控植物免疫网络的分子机制。本研究将揭示黄单胞菌non-TAL效应子的生化功能，分离水稻抗病途径中的新调控因子，为植物抗病分子设计提供关键靶标。

Rice bacterial leaf blight, caused by Xanthomonas oryzae pathovar oryzae (Xoo), is one of the most important bacterial diseases of rice. Both transcription activator-like (TAL) and non-TAL effectors secreted by Xoo are critical virulence factors of Xoo. However, the molecular virulence mechanisms of non-TAL effectors are largely unknown. Our previous study indicated that XOO499A, a non-TAL effector from Xoo strain PXO99A, suppressed plant defense responses when directly expressed in plants. We also found that OsRLK1 and OsRLK2, two homologous receptor like kinases, formed a protein complex with XOO499A in rice cells respectively. In current project, we will study the molecular mechanisms of XOO499A and OsRLK1/OsRLK2 interaction, and isolate additional host virulence targets of XOO499A. We will also investigate the function of OsRLK1/OsRLK2, and additional XOO499A targets in plants, in rice immunity, and uncover the mechanism of plant immune manipulation by XOO499A. This study will uncover the biochemical property of Xoo non-TAL effector, and isolate novel rice immune regulators, which will provide key targets for the molecular design of plant resistance.