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细菌效应蛋白模仿宿主HSP90下游蛋白破坏免疫
作者:小柯机器人 发布时间:2019/9/13 15:29:37

美国德克萨斯大学西南医学中心Vincent S. Tagliabracci研究组的最新发现,揭示细菌效应蛋白模仿宿主HSP90的下游蛋白来破坏免疫。该研究于2019年9月12日在线发表于《细胞》。

研究人员将HopBF1家族的细菌效应蛋白鉴定为真核特异性HSP90蛋白激酶。HopBF1采用最小蛋白激酶折叠,被HSP90识别为宿主下游蛋白。结果,HopBF1磷酸化HSP90以完全抑制伴侣蛋白的ATP酶活性。研究人员证明HSP90的磷酸化阻止了免疫受体的激活,从而引发植物的过敏反应。因此,HSP90的HopBF1依赖性磷酸化足以在被细菌病原体丁香假单胞菌(Pseudomonas syringae)感染的植物中诱导严重的疾病症状。

总的来说,这些结果揭示了具有毒素样特性的细菌效应蛋白激酶家族,并揭示了先前未知的背叛机制,即细菌病原体通过该机制调节宿主免疫。

据介绍,分子伴侣HSP90促进几种下游蛋白的折叠,包括先天免疫受体和蛋白激酶。HSP90是植物和动物免疫力的重要组成部分,但此前尚未报道直接靶向分子伴侣的致病策略。

附:英文原文

Title: A Bacterial Effector Mimics a Host HSP90 Client to Undermine Immunity

Author: Victor A. Lopez, Brenden C. Park, Dominika Nowak, Anju Sreelatha, Patrycja Zembek, Jessie Fernandez, Kelly A. Servage, Marcin Gradowski, Jacek Hennig, Diana R. Tomchick, Krzysztof Pawowski, Magdalena Krzymowska, Vincent S. Tagliabracci

Issue&Volume: 12 September 2019

Summary: 

The molecular chaperone HSP90 facilitates the folding of several client proteins, including innate immune receptors and protein kinases. HSP90 is an essential component of plant and animal immunity, yet pathogenic strategies that directly target the chaperone have not been described. Here, we identify the HopBF1 family of bacterial effectors as eukaryotic-specific HSP90 protein kinases. HopBF1 adopts a minimal protein kinase fold that is recognized by HSP90 as a host client. As a result, HopBF1 phosphorylates HSP90 to completely inhibit the chaperone’s ATPase activity. We demonstrate that phosphorylation of HSP90 prevents activation of immune receptors that trigger the hypersensitive response in plants. Consequently, HopBF1-dependent phosphorylation of HSP90 is sufficient to induce severe disease symptoms in plants infected with the bacterial pathogen, Pseudomonas syringae. Collectively, our results uncover a family of bacterial effector kinases with toxin-like properties and reveal a previously unrecognized betrayal mechanism by which bacterial pathogens modulate host immunity.

DOI: 10.1016/j.cell.2019.08.020

Source: https://www.cell.com/cell/fulltext/S0092-8674(19)30908-0

期刊信息
Cell:《细胞》,创刊于1974年。隶属于细胞出版社,最新IF:36.216
官方网址:https://www.cell.com/