Crystal structure of the type III effector AvrB from Pseudomonas syringae
Crystal structure of the type III effector AvrB from Pseudomonas syringae
复制标题
DOI：
10.1016/j.str.2004.02.013
复制
发表时间：
2004-03-01
期刊：
影响因子：
5.7
通讯作者：
Katagiri, F
中科院分区：
文献类型：
--
作者：
Lee, CC;Wood, MD;Katagiri, F
AvrB是一种假单胞菌III型效应蛋白，其在尝试致病期间易位到宿主植物细胞中。拟南芥中含有相应的抗性蛋白RPM 1，可以检测到AvrB，并启动快速的宿主防御反应，从而避免主动感染。在植物细胞中，AvrB诱导RIN 4的磷酸化，RIN 4是AvrB/RPM 1识别的关键组分。虽然AvrB/RPM 1系统是众多参与植物抗病性和发病机制的细菌效应子/植物抗性蛋白系统中最具特征的系统之一，但其分子识别机制的细节仍不清楚。为了获得进一步的见解，确定了AvrB的晶体结构。2.2埃的结构表现出一种新的混合α/β双叶折叠。借助于结构信息，我们证明了一个叶是AvrB/RPM 1识别特异性的决定因素。这些结构信息和初步的结构-功能研究为今后在分子水平上了解AvrB的功能提供了一个框架。
AvrB is a Pseudomonas syringae type III effector protein that is translocated into host plant cells during attempted pathogenesis. Arabidopsis harboring the corresponding resistance protein RPM1 can detect AvrB and mount a rapid host defense response, thus avoiding active infection. In the plant cell, AvrB induces phosphorylation of RIN4, a key component in AvrB/RPM1 recognition. Although the AvrB/RPM1 system is among the best characterized of the numerous bacterial effector/plant resistance protein systems involved in plant disease resistance and pathogenesis, the details of the molecular recognition mechanism are still unclear. To gain further insights, the crystal structure of AvrB was determined. The 2.2 Angstrom structure exhibits a novel mixed alpha/beta bilobal fold. Aided by the structural information, we demonstrate that one lobe is the determinant of AvrB/RPM1 recognition specificity. This structural information and preliminary structure-function studies provide a framework for the future understanding of AvrB function on the molecular level.