塞斯特林2驱动ER-phagy作为对蛋白质错误折叠的反应
Chiara De Leonibus1, Marianna Maddaluno2, Rosa Ferriero3
1Telethon Institute of Genetics and Medicine (TIGEM), Pozzuoli, Italy; Department of Health Sciences, University of Basilicata, Potenza, Italy.
Developmental cell
|August 2, 2024
概括
错误折叠的蛋白质通过SESTRIN2触发ER-phagy,抑制mTORC1并促进FAM134B. 这一途径清除ER储存障碍中的缺陷蛋白质,提供新的治疗点.
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:
- 蛋白质生物发生在细胞内膜网 (ER) 中对于细胞功能至关重要.
- 错误折叠的蛋白质在ER中积聚,需要像ER相关蛋白质降解和ER-phagy这样的降解途径.
- 作为对ER蛋白质稳定缺陷的反应,启动ER-phagy的机制尚不清楚.
研究的目的:
- 为了阐明启动ER-phagy响应ER蛋白质稳定缺陷的机制.
- 研究营养信号在ER质量控制中的作用.
- 确定ER存储障碍 (ERSD) 的潜在治疗策略.
主要方法:
- 作为模型,利用了来自ER存储障碍 (ERSD) 的小鼠原发细胞和患者样本.
- 研究了营养传感器SESTRIN2的作用及其与mTORC1信号的相互作用.
- 分析了转录因子TFEB/TFE3和ER-phagy受体FAM134B的调节.
主要成果:
- 在ER中错误折叠的蛋白质的积累触发了SESTRIN2的诱导.
- 塞斯特林2抑制mTORC1,导致TFEB/TFE3核转位和FAM134B和 lysosomal基因的上调调节.
- FAM134B-Calnexin复合体调解了错误折叠蛋白质的ER-phagy;药理上诱导FAM134B可以改善ERSD中的蛋白质清除.
结论:
- 发现了一种新的途径,将营养信号 (SESTRIN2-mTORC1) 与ER质量控制和ER-phagy联系起来.
- 证明SESTRIN2介导的mTORC1抑制对于启动ER-phagy至关重要.
- 表明针对ERSD中FAM134B介导的ER-phagy通路的治疗潜力.
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