“卫青不败由天幸”——WeiTsing的广谱抗根肿病机理被揭示

The Broad-spectrum Innate Resistance Against Clubroot Disease Conferred by WeiTsing is Mechanistically Revealed

芸苔根肿菌(Plasmodiophora brassicae,Pb)在世界范围内引起十字花科(Brassicaceae)植物病害,导致巨大的经济损失。近期,中国科学院遗传与发育生物学研究所的陈宇航和周俭民团队开展合作,成功从拟南芥(Arabidopsis thaliana)中分离出1个广谱抗根肿病的基因WTS(WeiTsing)。根肿菌的侵染诱导WTS在根部中柱鞘细胞上调表达。WTS编码1个定位于内质网的小蛋白,其能寡聚化形成1个新型的单孔五聚体。电生理实验表明,WTS聚合物是一类Ca2+通透性的阳离子选择性通道。根肿病原菌侵染激发WTS的Ca2+通道活性并激活强烈的下游防卫反应。携带WTS的油菜(Brassica napus)对根肿菌呈现出高抗表型。该研究不仅发现了一个类似抗病小体的Ca2+通透性阳离子通道,还揭示了一种特异在中柱鞘细胞中激活的全新免疫调控分子机制,为新型广谱抗病育种提供了新的思路和基因资源。

Clubroot,Plasmodiophora brassicae(Pb)caused devastating disease,results in severe yield losses on cruciferous crops worldwide.Recently,Yu-hang Chen,Jian-Min Zhou and their colleagues from the Institute of Genetics and Developmental Biology,Chinese Academy of Sciences reported the isolation and characterization of WeiTsing(WTS),a broad-spectrum clubroot resistance gene from Arabidopsis.WTS in Arabidopsisis was transcriptionally activated in the pericycle upon Pb infection to prevent pathogen colonization in the stele.WTS encodes a small protein that is localized in the endoplasmic reticulum(ER).The cryo-EM structure analysis has revealed a pentameric architecture of WeiTsing with a central pore,which was previously unknown.Electrophysiological analysis has demonstrated that WeiTsing functions as a calcium-permeable cation-selective channel.The Pb-mediated activation of the WTS channels induces immune responses,including cell death.Brassica napus plants carrying the WTS transgene have exhibited robust resistance to Pb.These findings have identified a novel ion channel similar to resistosomes,which triggers immune signaling in the pericycle.This discovery provides a valuable tool for the development of elite crop varieties.