甲基氨酸受体激活和脱敏的全调节的结构基础
bioRxiv : the preprint server for biology
|August 30, 2023
概括
阳性全调节剂 (PAMs) 和激动剂激活甲基酸盐受体 (mGluRs),而PAMs也会导致脱敏. 结构研究显示,PAMs重塑受体接口,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.
- 准mGluRs具有治疗潜力,但对作用于跨膜域 (TMDs) 的全调节器的理解是有限的.
- 识别奥思特里克和艾洛斯特里克对mGluR功能和结构的影响是关键.
研究的目的:
- 剖析 ortosteric 与 allosteric 配体对mGluRs 的不同功能和结构效应.
- 阐明正调节剂 (PAMs) 影响mGluR激活,脱敏和信号传递的机制.
- 为了确定PAM对mGluR构成的作用的结构基础.
主要方法:
- 电生理学和活细胞成像测试以评估mGluR功能.
- 合规传感器技术用于监控子单元之间的重新排列.
- 低温电子显微镜 (cryo-EM) 用于确定mGluR3.3的高分辨率结构.
主要成果:
- 激动剂和PAM都会激活和降低mGluRs的敏感性.
- PAMs表现出性作用,增强激素反应,并充当脱敏偏差激素.
- 冷-EM结构揭示了PAM诱导的对联体结合和跨膜域的构造变化,突出显示了一个滚动的TMD二元接口激活路径.
结论:
- PAMs显著改变mGluR的形状和功能,影响G蛋白和β-结的合.
- 了解这些全性机制,可以深入了解mGluR药理学和药物开发.
- 这项研究揭示了对mGluR激活和全调节的新型结构见解.
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