科學家發現一條連接質膜和葉綠體的病原體防禦途徑
作者:
小柯機器人發布時間:2020/8/25 13:42:46
中科院分子植物科學卓越創新中心Rosa Lozano-Duran課題組發現一條連接質膜和葉綠體的病原體防禦途徑。相關論文於2020年8月24日在線發表在《細胞》雜誌上。
研究人員發現,植物病毒編碼蛋白在激活植物防禦後會從質膜重新定位到葉綠體,從而幹擾葉綠體依賴性抗病毒水楊酸(SA)的生物合成。令人驚訝的是,研究人員發現來自不同界的植物病原體似乎已經融合發展為靶向葉綠體,並在與膜結合後削弱了SA依賴性防禦,這依賴於兩個亞細胞靶向信號,N-肉豆蔻醯化位點和葉綠體轉運肽。這種模式也存在於植物蛋白中,其中至少一種反過來激活了來自葉綠體的SA防禦。
綜上所述,這些結果表明植物中存在連接質膜與葉綠體並激活防禦的途徑,並且該途徑已被植物病原體在宿主-病原體共同進化過程中所選擇,從而通過抑制SA反應來促進毒力。
據悉,葉綠體是植物與病原體相互作用過程中防禦激素反應激活的關鍵因素。
附:英文原文
Title: A Defense Pathway Linking Plasma Membrane and Chloroplasts and Co-opted by Pathogens
Author: Laura Medina-Puche, Huang Tan, Vivek Dogra, Mengshi Wu, Tabata Rosas-Diaz, Liping Wang, Xue Ding, Dan Zhang, Xing Fu, Chanhong Kim, Rosa Lozano-Duran
Issue&Volume: 2020-08-24
Abstract: Chloroplasts are crucial players in the activation of defensive hormonal responsesduring plant-pathogen interactions. Here, we show that a plant virus-encoded proteinre-localizes from the plasma membrane to chloroplasts upon activation of plant defense,interfering with the chloroplast-dependent anti-viral salicylic acid (SA) biosynthesis.Strikingly, we have found that plant pathogens from different kingdoms seem to haveconvergently evolved to target chloroplasts and impair SA-dependent defenses followingan association with membranes, which relies on the co-existence of two subcellulartargeting signals, an N-myristoylation site and a chloroplast transit peptide. Thispattern is also present in plant proteins, at least one of which conversely activatesSA defenses from the chloroplast. Taken together, our results suggest that a pathwaylinking plasma membrane to chloroplasts and activating defense exists in plants andthat such pathway has been co-opted by plant pathogens during host-pathogen co-evolutionto promote virulence through suppression of SA responses.
DOI: 10.1016/j.cell.2020.07.020
Source: https://www.cell.com/cell/fulltext/S0092-8674(20)30885-0
Cell:《細胞》,創刊於1974年。隸屬於細胞出版社,最新IF:36.216