Deciphering the mechanism of action of the Phytophthora infestans effector Pi13628 in the suppression of MAMP-dependent signalling in tomato

卵菌是深分枝真核生物，包括拟南芥霜霉病的致病因子拟南芥透明operonospora Arabidopsis，或引起马铃薯和番茄晚疫病的疫霉。计算机分析预测，几种卵菌的基因组编码了大量所谓的RXLR-(EER)效应物，这些效应物被认为是操纵宿主细胞功能作为其感染策略的一部分。该项目的主要目标将包括在拟南芥和番茄中使用基于细胞的系统来鉴定和表征拟南芥和鼠疫杆菌的RXLR-（EER)效应物，这些效应物1)抑制由识别不变的微生物结构（称为病原体相关分子模式（pamp））引发的植物免疫反应，和/或2）干扰植物细胞中的囊泡运输系统。随后，包括生化和生理分析在内的补充方法将被执行，以确定候选RXLR-(EER)效应物的功能，并表征/发现它们的植物靶点。该系统的一个主要优点是将复杂的病原体-植物相互作用简化为纯粹的单个信号和同步的细胞自主反应，使其成为一种强大的高中通量工具，可以测试数百种效应物。

Oomycetes are deep-branching eukaryotes that include Hyaloperonospora arabidopsidis, the causal agent of downy mildew on Arabidopsis thaliana, or Phytophthora infestans which causes potato and tomato late blight. In silico analysis predicted that the genome of several oomycete species encodes for a large number of so-called RXLR-(EER) effectors that are assumed to manipulate host cellular functions as part of their infection strategy. The main objective of this project will consist to use a cell-based system in Arabidopsis and tomato to identify and characterize RXLR-(EER) effectors from H.arabidopsidis and P. infestans that 1) suppress plant immune responses triggered by the recognition of invariant microbial structures, termed Pathogen-Associated Molecular Patterns (PAMPs), and/or 2) interfere with the vesicle trafficking system in plant cells. Subsequently, complementary approaches including biochemical and physiological assays will be performed to ascribe functions to the candidate RXLR-(EER) effectors as well as characterizing/discovering their plant targets. A major advantage of the system is that it simplifies the complex pathogen-plant interactions to pure individual signals and synchronized cell-autonomous responses, making it as a powerful high-medium throughput tool to test hundreds of effectors.