玻璃杯细胞应激传感器IRE1β的激活是由粘素伴侣AGR2控制的
Eva Cloots1,2, Phaedra Guilbert1,2, Mathias Provost3,4
1Laboratory for ER stress and Inflammation, VIB Center for Inflammation Research, 9052, Ghent, Belgium.
The EMBO journal
|January 4, 2024
概括
陪伴者AGR2通过控制依诺西需要酶-1β (IRE1β) 的活性来调节肠道杯细胞中的未折叠蛋白质反应 (UPR). AGR2 起作用为静脉静止剂,防止自发的 IRE1β 激活,并确保适当的粘素产生.
科学领域:
- 细胞生物学 细胞生物学
- 分子生物学分子生物学
- 胃肠病学 胃肠病学
背景情况:
- 肠道杯细胞合成粘膜,需要高效的蛋白质折叠.
- 杯状细胞利用未折叠蛋白质反应 (UPR) 传感器的内醇要求酶-1β (IRE1β) 来管理粘素生产需求.
- 细胞伴侣对IRE1β活动的精确调节尚不清楚.
研究的目的:
- 为了研究伴侣AGR2在调节肠道杯细胞内的IRE1β活性中的作用.
- 阐明AGR2调节IRE1β介导信号的机制.
主要方法:
- 确定了AGR2作为一个与IRE1β相互作用的杯状细胞特异蛋白.
- 评估了AGR2结合对IRE1β寡合化和内核酶活性的影响.
- 在杯状细胞中消耗了内源AGR2以观察IRE1β激活.
- 利用AGR2突变 (催化缺乏和H117Y) 来评估它们对IRE1β活性的影响.
主要成果:
- AGR2 专门调节的是 IRE1β,而不是 IRE1α 的信号传输.
- 结合IRE1β的AGR2抑制了其寡合化和下游内核酶功能.
- AGR2 枯竭导致杯状细胞中自发的 IRE1β 激活.
- 缺乏催化活性或具有H117Y突变的AGR2突变不能抑制IRE1β活性.
结论:
- AGR2是杯细胞UPR的关键调节者.
- AGR2 作为一种静电剂,根据内质网膜条件控制 IRE1β 内核酶活性.
- AGR2的陪伴活动对于维持IRE1β稳态和适当的粘素合成至关重要.
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