mTORC1活动许可从 lysosomal 表面释放自己的许可
Aishwarya Acharya1, Constantinos Demetriades2
1Max Planck Institute for Biology of Ageing (MPI-AGE), 50931 Cologne, Germany; Cologne Graduate School of Ageing Research (CGA), 50931 Cologne, Germany.
Molecular cell
|November 1, 2024
概括
mTORC1的活动由其位置来调节. 抑制mTORC1将其困在溶酶体上,防止其释放以调节细胞功能,并可能避免徒劳的循环.
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:
- 营养信号汇聚在拉巴胺复合体1 (mTORC1) 的机械点上,这是细胞生理学的关键调节者.
- mTORC1的活动是由其在溶酶体和细胞质之间动态局部调节的,受Rag GTPases的影响.
- 控制mTORC1从溶酶体释放的机制以及其活性对局部化的影响尚未完全理解.
研究的目的:
- 研究mTORC1活动,局部化和从溶酶体释放之间的关系.
- 为了阐明Rag GTPases在mTORC1释放中的作用.
- 了解mTORC1抑制如何影响其亚细胞定位.
主要方法:
- 使用了人类细胞系.
- 通过抑制操纵mTORC1活动.
- 在包括饥饿在内的各种条件下观察到TFEB等基质的mTORC1局部化和酸化.
主要成果:
- 抑制mTORC1可以防止它从溶酶体释放出来,即使在饥饿期间也是如此.
- 在mTORC1抑制后观察到 lysosomal基质TFEB的持续酸化.
- "不活跃"的mtORC1导致了持续的Rag GTPase激活,表明释放的活跃调解.
结论:
- mTORC1控制其自身的 lysosomal 局部化,抑制有效地防止其释放.
- 这种机制可能会防止mTORC1的低效循环进入和关闭 lysosome.
- 拉格GTPases在调解mTORC1从溶酶体释放中发挥着至关重要的作用.
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