在 lysosomal 表面上对接 mTORC1 的结构基础
Kacper B Rogala1,2,3,4,5, Xin Gu1,2,3,4,5, Jibril F Kedir1,2,3,4,5
1Whitehead Institute for Biomedical Research, Cambridge, MA 02142, USA.
概括
拉巴胺复合物1 (mTORC1) 蛋白激酶的机械性标
科学领域:
- 细胞生物学
- 分子生物学
- 生物化学
背景情况:
- 拉巴胺复合体1 (mTORC1) 的机械性标是细胞生长的关键调节剂.
- 营养素和生长因子控制mTORC1的活动,影响其定位到溶解体.
- 拉格GTPase-Regulator复合体调节了依赖营养的mTORC1对溶解体的招募.
研究的目的:
- 阐明mTORC1与Rag GTPase-Regulator复合体相互作用的结构基础.
- 了解营养物质的可用性如何调节mTORC1的局部化和激活.
- 为 lysosomal 表面提供活跃的 mTORC1 的结构模型.
主要方法:
- 使用冷电子显微镜 (cryo-EM) 来确定猛禽-虫-虫超级复合物的结构.
- 生物化学测定和突变分析用于评估Rag- Raptor相互作用的功能影响.
- 使用mTORC1-Rheb复合体进行了比较结构分析.
主要成果:
- 冷-EM结构揭示了猛禽子单元与Rag GTPases之间的详细相互作用,定义了核酸感应机制.
- 猛禽直接感知RagA和RagC的核酸结合状态,这对mTORC1的招募至关重要.
- 破坏Rag-Raptor结合导致mTORC1 lysosomal局部化和信号传递受损,这证实了这些相互作用的功能重要性.
结论:
- 这项研究提供了mTORC1-Rag-Regulator复合体的高分辨率结构,揭示了营养信号如何传输到mTORC1.
- 这些发现澄清了mTORC1局部化到溶酶体并激活的分子机制.
- 建议在溶酶体上对接的mTORC1模型,整合结构和功能数据.
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