細菌效應蛋白模仿宿主HSP90下遊蛋白破壞免疫
作者:
小柯機器人發布時間:2019/9/13 15:29:37
美國德克薩斯大學西南醫學中心Vincent S. Tagliabracci研究組的最新發現,揭示細菌效應蛋白模仿宿主HSP90的下遊蛋白來破壞免疫。該研究於2019年9月12日在線發表於《細胞》。
研究人員將HopBF1家族的細菌效應蛋白鑑定為真核特異性HSP90蛋白激酶。HopBF1採用最小蛋白激酶摺疊,被HSP90識別為宿主下遊蛋白。結果,HopBF1磷酸化HSP90以完全抑制伴侶蛋白的ATP酶活性。研究人員證明HSP90的磷酸化阻止了免疫受體的激活,從而引發植物的過敏反應。因此,HSP90的HopBF1依賴性磷酸化足以在被細菌病原體丁香假單胞菌(Pseudomonas syringae)感染的植物中誘導嚴重的疾病症狀。
總的來說,這些結果揭示了具有毒素樣特性的細菌效應蛋白激酶家族,並揭示了先前未知的背叛機制,即細菌病原體通過該機制調節宿主免疫。
據介紹,分子伴侶HSP90促進幾種下遊蛋白的摺疊,包括先天免疫受體和蛋白激酶。HSP90是植物和動物免疫力的重要組成部分,但此前尚未報導直接靶向分子伴侶的致病策略。
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
Cell:《細胞》,創刊於1974年。隸屬於細胞出版社,最新IF:36.216