积极的全osteric调节的结构基础的metabotropic谷氨酸受体激活和内部化
Alexa Strauss1,2, Alberto J Gonzalez-Hernandez1, Joon Lee1
1Department of Biochemistry, Weill Cornell Medicine, New York, NY, 10065, USA.
Nature communications
|August 1, 2024
概括
积极的全调节剂 (PAMs) 激活和内化甲基酸盐受体 (mGluRs),独立地起作用或增强 Orthosteric 激动剂. 结构研究显示,PAMs重塑受体结构,影响信号通路.
科学领域:
- 神经科学是一个神经科学.
- 药理学 药理学是指药理学的学科.
- 结构生物学 结构生物学
背景情况:
- 甲基胺基因组受体 (mGluRs) 是G蛋白合受体,对神经调节至关重要.
- 它们作为二元体起作用,将带结合域 (LBD) 与跨膜域 (TMD) 连接起来进行信号传输.
- 向TMD的阿洛斯特基调节器具有治疗潜力,但其机制尚未完全理解.
研究的目的:
- 剖析 ortosteric 与 allosteric 配体对mGluRs 的功能性和结构性影响.
- 阐明正调节剂 (PAMs) 影响mGluR激活和信号的机制.
- 用冷电子显微镜确定PAM作用的结构基础.
主要方法:
- 电生理学和活细胞成像测试以评估mGluR激活和内部化.
- 福斯特共振能量转移 (FRET) 分析用于研究子单位间的形状变化.
- 低温电子显微镜 (cryo-EM) 用于在不同配体的存在下确定mGluR3的高分辨率结构.
主要成果:
- ортостерик激动剂和PAM都激活并诱导II组和III组mGluRs的内化.
- PAMs表现出性效应:它们增强最大的正统性激动因子反应,并充当内化偏差激动因子.
- 低温EM结构显示,PAMs诱导mGluR3的显著形状变化,重塑了子单元内部和子单元之间的接口.
- 发现了一种滚动的TMD二元接口激活通路,可以控制G蛋白和β-止素的合.
结论:
- PAMs代表了一个独特的mGluR调节器类别,具有复杂的功能作用.
- PAMs可以使受体信号向内部化倾向,独立于正统的连接体结合.
- 结构洞察力揭示了一种涉及TMD二元接口动态的新型激活机制.
- 这些发现促进了对全调节的理解,并为开发针对mGluRs的新疗法提供了信息.
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