SAMTOR是一个mTORC1通路的S-adenosylmethionine传感器
Xin Gu1,2,3,4, Jose M Orozco1,2,3,4, Robert A Saxton1,2,3,4
1Whitehead Institute for Biomedical Research and Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02142, USA.
概括
SAMTOR是一种新型蛋白质,作为S- 腺甲 (SAM) 的传感器,将甲素代谢与mTORC1信号连接起来. 在SAM水平较低时抑制mTORC1,促进细胞生长调节.
科学领域:
- 细胞生物学
- 代谢过程
- 信号传输
背景情况:
- mTOR复合体1 (mTORC1) 是细胞生长和新陈代谢的关键调节剂.
- 营养的可用性通过Rag GTPases和 lysosomal定位影响mTORC1的活动.
- 了解mTORC1的上游调节者对于破译细胞对环境信号的反应至关重要.
研究的目的:
- 识别和描述mTORC1信号的新型调节剂.
- 阐明氨酸代谢影响mtORC1活动的机制.
- 研究SAMTOR蛋白在营养感应中的作用.
主要方法:
- 蛋白与蛋白相互作用研究以确定SAMTOR的结合伙伴.
- 生物化学测试以确定SAMTOR和S-adenosylmethionine (SAM) 的结合动力学
- 细胞实验以评估mTORC1信号响应于氨酸的可用性和SAMTOR操纵.
主要成果:
- SAMTOR通过与Rag GTPase激活蛋白质GATOR1相互作用,被确定为mTORC1信号的抑制剂.
- S-adenosylmethionine (SAM) 直接与SAMTOR结合,从而破坏了SAMTOR- GATOR1复合体.
- 甲因饥饿会降低细胞中的SAM水平,促进SAMTOR- GATOR1协会,并以SAMTOR依赖的方式抑制mTORC1信号传递.
结论:
- SAMTOR作为SAM的传感器,直接将甲和单碳代谢与mTORC1信号连接起来.
- SAMTOR的SAM结合能力对于 metionin诱导的mTORC1激活至关重要.
- SAMTOR代表了代谢状态和细胞生长调节之间的新分子联系.
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