小柯机器人

中国科学院遗传与发育生物学研究所周俭民等研究人员合作发现，ZAR1抵抗小体是一种钙离子渗透通道，可触发植物免疫信号。这一研究成果于2021年5月12日在线发表在国际学术期刊《细胞》上。

研究人员采用单分子成像发现，活化的ZAR1蛋白可以在质膜中形成五聚体复合物。ZAR1抵抗小体在非洲爪蟾卵母细胞中以依赖位于通道孔中的保守酸性残基Glu11的方式显示离子通道活性。预组装的ZAR1脂质体很容易掺入平面脂质双层中，并表现出钙离子渗透的阳离子选择性通道活性。

此外，研究人员显示ZAR1在植物细胞中的激活导致Glu11依赖的Ca²⁺涌入、亚细胞结构的扰动、活性氧的产生以及细胞死亡。因此，这些结果表明，ZAR1抵抗小体作为钙离子渗透的阳离子通道，从而触发免疫和细胞死亡。

据了解，核苷酸结合的、富含亮氨酸的重复受体（NLR）是动植物中的主要免疫受体。激活后，拟南芥NLR蛋白ZAR1在体外形成五聚体抵抗小体，并触发植物的免疫反应和细胞死亡。

附：英文原文

Title: The ZAR1 resistosome is a calcium-permeable channel triggering plant immune signaling

Author: Guozhi Bi, Min Su, Nan Li, Yu Liang, Song Dang, Jiachao Xu, Meijuan Hu, Jizong Wang, Minxia Zou, Yanan Deng, Qiyu Li, Shijia Huang, Jiejie Li, Jijie Chai, Kangmin He, Yu-hang Chen, Jian-Min Zhou

Issue&Volume: 2021-05-12

Abstract: Nucleotide-binding, leucine-rich repeat receptors (NLRs) are major immune receptorsin plants and animals. Upon activation, the Arabidopsis NLR protein ZAR1 forms a pentameric resistosome in vitro and triggers immune responses and cell death in plants. In this study, we employedsingle-molecule imaging to show that the activated ZAR1 protein can form pentamericcomplexes in the plasma membrane. The ZAR1 resistosome displayed ion channel activityin Xenopus oocytes in a manner dependent on a conserved acidic residue Glu11 situated in thechannel pore. Pre-assembled ZAR1 resistosome was readily incorporated into planarlipid-bilayers and displayed calcium-permeable cation-selective channel activity.Furthermore, we show that activation of ZAR1 in the plant cell led to Glu11-dependentCa2+ influx, perturbation of subcellular structures, production of reactive oxygen species,and cell death. The results thus support that the ZAR1 resistosome acts as a calcium-permeablecation channel to trigger immunity and cell death.

DOI: 10.1016/j.cell.2021.05.003

Source: https://www.cell.com/cell/fulltext/S0092-8674(21)00600-0