杨树炭疽病菌附着胞形成相关识别受体蛋白功能及信号传导机制研究

杨树炭疽病是由胶孢炭疽菌引起的一种重要叶部病害，该病菌感受到寄主信号后，通过形成特异的侵染结构“附着胞”侵入寄主。附着胞形成及病原菌侵入的分子机制已成为植物病理学的研究热点。然而，植物病原菌如何将识别的胞外寄主诱导信号传导到胞内，并激活下游关键信号通路，从而调控附着胞形成的分子机制并不十分清楚。本项目拟以杨树—胶孢炭疽菌的互作体系为研究对象，对筛选到的胶孢炭疽菌的4个感受寄主诱导信号及胞内信号传导的附着胞形成关键受体蛋白，通过多基因敲除探究受体蛋白的协同功能，结合活细胞成像技术分析各受体蛋白的定位及其胞内时空转运动态，进而鉴定受体蛋白内化和转运的互作蛋白，并通过磷酸化和双分子荧光互补等明确“受体识别—信号传导—下游通路”的调控网络，揭示其如何将外源信号传导到胞内并激活下游信号通路的机制。项目的实施有助于阐明附着胞形成的信号识别及传导机制，并对植物与病原菌分子互作机制的研究提供重要的参考。

Poplar anthracnose is an important foliar disease caused by Colletotrichum gloeosporioides, it gains entry to its host plant by means of a specialized infection structure called appressorium after the recognition of specific plant signal. Therefore, the molecular mechanisms of appressorium formation is one of the hotspot in molecular plant pathology research. However, the molecular process of appressorium formation during the recognition of plant signal and the signal transduction from membrane to the intracellular remain largely unknown. Here, we focus on the Populus-Colletotrichum gloeosporioides interaction system, especially the signal transduction and activation of downstream pathway during appressorium formation. In our recent studies, we identified four receptors that involved in appressorium formation, they all showed conservative roles in signal recognition. Our research proposal include that determine the redundant functions among these receptors with multiple gene knockout, observing the dynamic moving of receptor proteins during appressorium formation with live-cell imaging technology, identifying genes responsible for the transduction of receptor using protein hybridization, and determining the molecular pathway of receptor recognition-signal and transduction- downstream activation with bimolecular fluorescence complementation (BIFC) and western blot. Those studies could accelerate the study of signal recognition and transduction mechanism during appressorium formation, which will promote the development of molecular study of tree-pathogen.