中国科学院遗传与发育生物学研究所陈宇航等研究人员合作发现，一个在中柱鞘表达的离子通道保护中柱来赋予根肿病抗性。这一研究成果于2023年6月8日发表在国际学术期刊《细胞》上。
研究人员报告了WeiTsing（WTS）的分离和特征，这是一个来自拟南芥的广谱抗根肿病基因。WTS在甘蓝根肿菌（Pb）感染后在中柱鞘转录激活，从而防止病原体在茎秆上定植。携带WTS转基因的油菜对Pb表现出强烈的抗性。WTS编码一个定位在内质网（ER）的小蛋白，它在植物中的表达能诱导免疫反应。WTS的冷冻电镜（cryo-EM）结构显示了一个以前未知的具有中心孔的五元结构。电生理学分析表明，WTS是一个钙渗透性阳离子选择通道。结构指导下的诱变表明，通道活性对触发防御是严格要求的。这些发现揭示了一个类似于抵抗体的离子通道，它在中柱鞘触发了免疫信号。
据介绍，植物的根部会遇到许多病原微生物，它们往往会引起破坏性的疾病。其中一种病原体Pb在全世界范围内导致了十字花科作物的根肿病和严重的产量损失。
附：英文原文
Title: WeiTsing, a pericycle-expressed ion channel, safeguards the stele to confer clubroot resistance
Author: Wei Wang, Li Qin, Wenjing Zhang, Linghui Tang, Chao Zhang, Xiaojing Dong, Pei Miao, Meng Shen, Huilong Du, Hangyuan Cheng, Ke Wang, Xiangyun Zhang, Min Su, Hongwei Lu, Chang Li, Qiang Gao, Xiaojuan Zhang, Yun Huang, Chengzhi Liang, Jian-Min Zhou, Yu-hang Chen
Issue&Volume: 2023/06/08
Abstract: Plant roots encounter numerous pathogenic microbes that often cause devastating diseases. One such pathogen, Plasmodiophora brassicae (Pb), causes clubroot disease and severe yield losses on cruciferous crops worldwide. Here, we report the isolation and characterization of WeiTsing (WTS), a broad-spectrum clubroot resistance gene from Arabidopsis. WTS is transcriptionally activated in the pericycle upon Pb infection to prevent pathogen colonization in the stele. Brassica napus carrying the WTS transgene displayed strong resistance to Pb. WTS encodes a small protein localized in the endoplasmic reticulum (ER), and its expression in plants induces immune responses. The cryoelectron microscopy (cryo-EM) structure of WTS revealed a previously unknown pentameric architecture with a central pore. Electrophysiology analyses demonstrated that WTS is a calcium-permeable cation-selective channel. Structure-guided mutagenesis indicated that channel activity is strictly required for triggering defenses. The findings uncover an ion channel analogous to resistosomes that triggers immune signaling in the pericycle.
DOI: 10.1016/j.cell.2023.05.023
Source: https://www.cell.com/cell/fulltext/S0092-8674(23)00542-1