描绘了C类GPCR二分体mGlu5的阶段性毫秒性激活机制
Mingyu Li1,2, Xiaobing Lan2, Xinchao Shi1
1State Key Laboratory of Medical Genomics, National Research Center for Translational Medicine at Shanghai, Medicinal Chemistry and Bioinformatics Center, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, 200025, China.
Nature communications
|August 29, 2024
概括
G蛋白结合受体 (GPCRs) 是重要的药物标. 这项研究揭示了二进制甲基酸盐受体5 (mGlu5) 的毫秒性激活机制,揭示了受体信号传递的关键步骤.
科学领域:
- 生物化学和分子药理学
- 结构生物学 结构生物学
- 神经科学是一个神经科学.
背景情况:
- G蛋白结合受体 (GPCRs) 调解细胞对激素和神经递质的反应.
- 虽然单体GPCR激活已被理解,但二极体GPCR机制在很大程度上仍未知.
- 甲基增生谷氨酸受体5 (mGlu5) 是一个强制性二维C类GPCR和一个关键的神经学标.
研究的目的:
- 阐明二次mGlu5受体的全激活机制.
- 以毫秒时间尺度来描述在受体激活过程中发生的动态形状变化.
- 调查积极的全调节剂在mGlu5受体信号传递中的作用.
主要方法:
- 原子模拟和马尔科夫状态建模用于生成过渡路径.
- 实验信号测试用于验证计算发现.
- 对受体动态的分析,包括ectodomain紧缩和7-transmembrane (7TM) 域相互作用.
主要成果:
- 揭示了一种不对称的,逐步的毫秒激活机制,用于二维mGlu5.5.
- 激素结合诱导了ectodomain紧缩,并使7TM域相邻,形成了一个不对称的TM6-TM6接口.
- 积极的全调节剂稳定了活跃的7TM接口和扩展的ICL2形状,促进了G蛋白结合.
结论:
- 该研究提供了一种动态模型,用于二度C类GPCRs的全激活.
- 了解mGlu5激活为神经系统疾病和药物开发提供了洞察力.
- 采用的计算策略可能适用于其他全系统.
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