病原體能夠直接誘導NLR免疫受體複合物組裝形成全酶
作者:
小柯機器人發布時間:2020/12/4 16:58:44
清華大學柴繼傑等研究人員合作發現,病原體能夠直接誘導NLR免疫受體複合物組裝形成全酶。該項研究成果發表在2020年12月4日出版的《科學》雜誌上。
研究人員表示,通過植物核苷酸結合的亮氨酸富含重複序列(LRR)受體(NLR)直接或間接識別病原體來源的效應蛋白能夠啟動先天免疫應答。病原體Hyaloperonospora arabidopsidis效應蛋白ATR1激活擬南芥NLR RPP1的N端Toll-白介素1受體(TIR)域。
研究人員報告了ATR1結合時的RPP1冷凍電鏡。該結構揭示了一個C-JID結構域(C-terminal jelly roll/Ig-like domain),用於特定的ATR1識別。生化和功能分析表明,ATR1與C-JID和LRR結合,來誘導煙醯胺腺嘌呤二核苷酸水解酶(NADase)活性所需的RPP1四聚體組裝。RPP1四聚產生兩個潛在的活性位點,每個活性位點由不對稱的TIR同型二聚體形成。
這些數據定義了一種直接的效應子識別機制,這是通過一種植物NRL導致的信號活化型全酶的形成來實現。
附:英文原文
Title: Direct pathogen-induced assembly of an NLR immune receptor complex to form a holoenzyme
Author: Shoucai Ma, Dmitry Lapin, Li Liu, Yue Sun, Wen Song, Xiaoxiao Zhang, Elke Logemann, Dongli Yu, Jia Wang, Jan Jirschitzka, Zhifu Han, Paul Schulze-Lefert, Jane E. Parker, Jijie Chai
Issue&Volume: 2020/12/04
Abstract: Direct or indirect recognition of pathogen-derived effectors by plant nucleotide-binding leucine-rich repeat (LRR) receptors (NLRs) initiates innate immune responses. The Hyaloperonospora arabidopsidis effector ATR1 activates the N-terminal Toll–interleukin-1 receptor (TIR) domain of Arabidopsis NLR RPP1. We report a cryo–electron microscopy structure of RPP1 bound by ATR1. The structure reveals a C-terminal jelly roll/Ig-like domain (C-JID) for specific ATR1 recognition. Biochemical and functional analyses show that ATR1 binds to the C-JID and the LRRs to induce an RPP1 tetrameric assembly required for nicotinamide adenine dinucleotide hydrolase (NADase) activity. RPP1 tetramerization creates two potential active sites, each formed by an asymmetric TIR homodimer. Our data define the mechanism of direct effector recognition by a plant NLR leading to formation of a signaling-active holoenzyme.
DOI: 10.1126/science.abe3069
Source: https://science.sciencemag.org/content/370/6521/eabe3069
Science:《科學》,創刊於1880年。隸屬於美國科學促進會,最新IF:41.037