作为ER Ca2+恒温的哨兵机制的ER压力
Tadashi Makio1, Junsheng Chen1, Thomas Simmen1
1Department of Cell Biology, Faculty of Medicine and Dentistry, University of Alberta, Edmonton T6G2H7, Alberta, Canada.
Cell calcium
|October 29, 2024
概括
细胞内膜网膜 (ER) 的压力会破坏蛋白质折叠和Ca2+平衡,影响细胞生物能学,并可能导致疾病. 了解ER Ca2+信号对于组织功能和疾病预防至关重要.
科学领域:
- 细胞生物学 细胞生物学
- 生物化学 生物化学
- 分子生物学分子生物学
背景情况:
- 细胞内膜网膜 (ER) 应激产生于氧化蛋白折叠的破坏,影响蛋白质成熟和退出.
- 像BiP/GRP78,calnexin和calreticulin这样的关键ER陪伴者依赖Ca2+结合功能.
- ER压力会诱导Ca2+失调,包括细胞质Ca2+的增加和储存Ca2+输入 (SOCE) 的激活.
研究的目的:
- 为了研究ER压力,Ca2+处理和细胞反应之间的复杂关系.
- 阐明翻译后修改在压力期间调节ER Ca2+信号传递中的作用.
- 了解ER Ca2+动态如何影响线粒体功能和细胞命运.
主要方法:
- 对与ER伴侣体结合的Ca2+离子的分析.
- 研究药物诱导的ER压力及其对细胞质Ca2+水平的影响.
- 检查ER Ca2+处理蛋白的翻译后修饰 (酸化,氧化) (SERCA,IP3Rs,STIM1).
- 评估ER Ca2+转移到线粒体的影响.
- 研究像ERO1,PDI和ERp57.7这样的氧化还原控制酶.
主要成果:
- ER压力干扰了伴侣Ca2+结合,并改变了细胞溶液Ca2+水平.
- 对Ca2+处理蛋白的ER压力依赖的PTM调节Ca2+稳态和ER-线粒体Ca2+转移.
- 在ER压力期间增加ER-线粒体Ca2+转移可以增强生物能效,但也会触发细胞亡.
- 对ER Ca2+工具包蛋白质的氧化修饰发生在ER光层或细胞质中.
- 在各种组织中,ER Ca2+含量,ER应激和线粒体活动之间存在功能联系.
结论:
- ER Ca2+稳态受到ER压力和PTMs的严格调节.
- ER Ca2+信号的失调有助于肌肉缺陷和糖尿病等疾病.
- 准ER Ca2+通路可能为与压力相关的疾病提供治疗策略.
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