ER Ca2+ 过载激活了 IRE1α 信号,并促进了细胞生存
Song Zhao1,2, Haiping Feng1,2, Dongfang Jiang1,2
1State Key Laboratory of Membrane Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, 100101, China.
Cell & bioscience
|July 3, 2023
概括
细胞内膜网膜 (ER) 的Ca2+过载直接激活IRE1α-XBP1通路,这是细胞信号传递的一个新发现. 这种激活对于预防TMCO1缺乏细胞中的细胞死亡至关重要.
科学领域:
- 细胞生物学 细胞生物学
- 分子生物学分子生物学
- 信号传递 信号传递
背景情况:
- 维持内等质网膜 (ER) (Ca2+) 稳态对于细胞功能至关重要.
- ER Ca2+ 枯竭会触发ER压力和未折叠蛋白质反应 (UPR).
- 对于UPR传感器对ER Ca2+过载的反应尚不清楚.
研究的目的:
- 为了研究ER Ca2+过载对UPR传感器的影响.
- 阐明ER Ca2+过载影响IRE1α-XBP1轴的机制.
主要方法:
- 研究了具有超载ER Ca2+储备的TMCO1缺乏细胞.
- 评估BiP与IRE1α的分离.
- 分析了 IRE1α 的二分化,稳定性和激活.
- 使用IRE1α抑制剂来评估IRE1α-XBP1s信号在细胞死亡中的作用.
主要成果:
- 在ER Ca2+过载直接使 IRE1α-XBP1轴变得敏感.
- 在TMCO1缺乏细胞中的超载ER Ca2+促进BiP与IRE1α的解离.
- 这导致增强的IRE1α二分化,稳定性和激活.
- 抑制过度激活的IRE1α-XBP1s信号产生显著的细胞死亡.
结论:
- 在ER Ca2+过载和选择性IRE1α-XBP1轴激活之间建立了直接联系.
- 证明ER Ca2+过载在激活IRE1α方面发挥了意想不到的作用.
- 突出了ER Ca2+过载诱导的IRE1α激活对细胞死亡的保护作用.
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