PERK和IRE1α通过阻断多个膀体的溶酶体降解来促进外体分泌
Shixin Zhou1, Zihan Zhou1, Si Chen1
1State Key Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, P.R. China; College of Life Sciences, University of Chinese Academy of Sciences, Beijing, P.R. China.
The Journal of biological chemistry
|July 23, 2025
概括
细胞内膜网膜 (ER) 的压力通过未折叠的蛋白质反应 (UPR) 触发了外体分泌. 这一过程涉及PERK和IRE1α通路抑制 lysosomes,促进细胞通信的外体释放.
科学领域:
- 细胞生物学 细胞生物学
- 分子生物学分子生物学
- 生物化学 生物化学
背景情况:
- 展开的蛋白质反应 (UPR) 在压力期间保持内细胞网膜 (ER) 稳态.
- 外体,通过非传统的途径分泌,调解细胞间的通信.
- 人们还不太了解UPR对外体分泌的调节.
研究的目的:
- 调查UPR是否以及如何调节外体分泌.
- 阐明将ER压力,UPR和外体细胞释放联系在一起的分子机制.
主要方法:
- 在细胞模型中诱导ER应力和UPR激活.
- 对外体分泌率和特征的分析.
- 研究溶酶体功能,MVB-溶酶体融合和MVB贩运.
- 对UPR通路 (PERK, IRE1α) 和下游因素 (ATF4) 的药理和遗传操纵.
主要成果:
- 在ER压力显著诱导UPR-依赖的外分泌物分泌.
- 激活PERK和IRE1α可以抑制 lysosomal 酸化和代谢活性.
- 这种抑制阻断了多胞体 (MVB) lysosome 融合,有利于 MVB-等离子膜融合和外体释放.
- 即使没有ER压力,PERK激活也会通过ATF4增加外体分泌,抑制 lysosomal 降解.
结论:
- 通过UPR激活,ER压力促进了外体分泌.
- 在调节 lysosomal 功能和 MVB 命运方面,PERK 和 IRE1α 起着至关重要的作用.
- 这种机制通过在ER应激过程中通过外体释放增强了细胞间的细胞间通信.
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