通过tRNA-GCN2-FBXO22轴介导的mTOR无处不在感应氨基酸不足
Meng-Kai Ge1, Cheng Zhang2, Na Zhang3
1Institute of Aging & Tissue Regeneration, State Key Laboratory of Systems Medicine for Cancer and Stress and Cancer Research Unit of Chinese Academy of Medical Sciences (No. 2019RU043), Ren-Ji Hospital, Shanghai Jiao Tong University School of Medicine (SJTU-SM), Shanghai 200127, China; Department of Pathophysiology, Key Laboratory of Cell Differentiation and Apoptosis of Chinese Ministry of Education, SJTU-SM, Shanghai 200025, China.
Cell metabolism
|November 18, 2023
概括
细胞氨基酸水平通过一种新的无处不在途径调节mTORC1的活动. 未充电的tRNA触发GCN2和FBXO22,使mTOR无处不在,在营养稀缺期间抑制其激酶功能.
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:
- 拉巴胺素复合体1 (mTORC1) 的哺乳动物点是细胞生长和新陈代谢的关键调节者.
- mTORC1感知细胞营养水平,特别是氨基酸,但精确的分子机制尚未完全阐明.
- 了解mTORC1的氨基酸感应对于理解细胞平衡和代谢疾病至关重要.
研究的目的:
- 为了确定将细胞氨基酸可用性与mTORC1活性联系起来的分子媒介.
- 阐明氨基酸耗尽调节mTORC1激酶功能的机制.
- 通过mTORC1.1.发现一种新的氨基酸感应途径.
主要方法:
- 研究了mTOR在对不同细胞氨基酸度的反应中存在的无处不在状态.
- 利用基因操纵 (例如,mTOR Lys2066的突变) 和生物化学分析来剖析信号通路.
- 采用体外和体内模型来评估已识别的途径的功能后果.
主要成果:
- 氨基酸枯竭诱导了mTOR在Lys2066的无处不在,特别是通过一种与K27相关的方式.
- 这种无处不在的事件通过阻止基质招募来抑制mTORC1激酶活性.
- 该途径涉及未充电的tRNA,GCN2激活和FBXO22介导的mTOR的无处不在.
结论:
- 一个新的GCN2-FBXO22-mTOR通路通过mTORC1.1.介导氨基酸传感.
- 未充电的tRNAs作为一个独特的信号来触发mTOR无化,并抑制mTORC1.1.
- 这种机制为细胞如何适应营养缺乏提供了新的理解.
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