美国北卡罗来纳大学Jeffery L. Dangl等研究人员合作发现,植物“辅助”免疫受体是Ca2+可渗透的非选择性阳离子通道。这一研究成果于2021年6月17日在线发表在国际学术期刊《科学》上。
研究人员发现,在拟南芥中,许多“传感器”(核苷酸结合的富含亮氨酸重复受体NLR) 需要一个“辅助”NLR亚家族。活性NRG1.1寡聚化,在质膜斑点中富集,并实现植物和人类细胞中的细胞质Ca2+流入。NRG1.1依赖的Ca2+流入和细胞死亡对Ca2+通道阻滞剂敏感,并且受到影响寡聚化或质膜富集的突变的抑制。
由NRG1.1和ADR1(ACTIVATED DISEASE RESISTANCE 1)介导的Ca2+流入和细胞死亡,另一种“辅助”NLR,需要保守的带负电荷的N端残基。全细胞电压钳记录表明拟南芥“辅助”NLR形成Ca2+可渗透的阳离子通道,直接调节细胞质Ca2+水平和随后的细胞死亡。因此,“辅助”NLR直接转导细胞死亡信号。
据了解,植物NLR调节免疫和细胞死亡。
附:英文原文
Title: Plant “helper” immune receptors are Ca2+-permeable nonselective cation channels
Author: Pierre Jacob, Nak Hyun Kim, Feihua Wu, Farid El-Kasmi, Yuan Chi, William G. Walton, Oliver J. Furzer, Adam D. Lietzan, Sruthi Sunil, Korina Kempthorn, Matthew R. Redinbo, Zhen-Ming Pei, Li Wan, Jeffery L. Dangl
Issue&Volume: 2021/06/17
Abstract: Plant nucleotide-binding leucine-rich repeat receptors (NLRs) regulate immunity and cell death. In Arabidopsis, a subfamily of “helper” NLRs are required by many “sensor” NLRs. Active NRG1.1 oligomerized, was enriched in plasma membrane puncta and conferred cytoplasmic Ca2+ influx in plant and human cells. NRG1.1-dependent Ca2+ influx and cell death were sensitive to Ca2+ channel blockers and were suppressed by mutations impacting oligomerization or plasma membrane enrichment. Ca2+ influx and cell death mediated by NRG1.1 and ACTIVATED DISEASE RESISTANCE 1 (ADR1), another “helper” NLR, required conserved negatively charged N-terminal residues. Whole-cell voltage-clamp recordings demonstrate that Arabidopsis “helper” NLRs form Ca2+-permeable cation channels to directly regulate cytoplasmic Ca2+ levels and consequent cell death. Thus, “helper” NLRs transduce cell death signals directly.
DOI: 10.1126/science.abg7917
Source: https://science.sciencemag.org/content/early/2021/06/16/science.abg7917
本期文章:《科学》:Online/在线发表