通过CASTOR1-GATOR2复合体进行mTORC1调节的结构基础
Rachel M Jansen1,2, Clément Maghe1,2, Karla Tapia1
1Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, CA, USA.
Nature structural & molecular biology
|July 27, 2025
概括
这项研究揭示了素传感器CASTOR1如何与GATOR2复合体相互作用,以调节mTORC1的激活. 这种相互作用对于控制细胞代谢以响应营养的可用性至关重要.
科学领域:
- 细胞代谢的细胞代谢.
- 分子生物学分子生物学
- 信号传导传导是指信号的传导.
背景情况:
- 拉巴胺素复合体1 (mTORC1) 的机械标调节细胞代谢.
- 氨基酸可用性控制mTORC1通过Rag GTPases在溶酶体.
- 在营养缺乏的情况下,GATOR1通过GATOR2和氨基酸传感器进行调节,使mTORC1失活.
研究的目的:
- 阐明CASTOR1对氨酸感应的结构机制及其与GATOR的相互作用2.
- 要了解CASTOR1如何与GATOR2结合,在低氨酸条件下对GATOR1进行消毒.
主要方法:
- 用冷电子显微镜 (cryo-EM) 确定人体GATOR2与CASTOR1.1结合的结构.
- 蛋白质与蛋白质相互作用和调节机制的生物化学分析.
主要成果:
- 冷-EM结构显示了GATOR2的两个MIOS WD40域与CASTOR1同位体发生交互.
- 卡斯托1的MIOS绑定接口,距离氨酸口袋,与GATOR2相互作用.
- 氨酸结合诱导了CASTOR1中的循环排序,阻断了MIOS结合接口并破坏了GATOR2的相互作用.
结论:
- 结构机制解释了氨酸的可用性如何调节CASTOR1-GATOR2结合.
- 这种调节有效地将营养状况传达给mTORC1通路.
- 这些发现为分子层面的营养感知和代谢控制提供了洞察力.
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