pH驱动的AR动力学揭示了循环介导的体通信
Nuray Sogunmez Erdogan1, E Demet Akten2
1Kadir Has University, Faculty of Engineering and Natural Sciences, Molecular Biology and Genetics, Istanbul 34083, Türkiye.
ACS omega
|March 2, 2026
概括
恒定pH分子动力学揭示了pH的变化通过改变质子状态,影响β-2上腺素受体 (β2AR) 中环的灵活性. 这些变化会影响受体动态,但不会诱导类似激活的状态.
科学领域:
- 生物化学 生物化学
- 计算生物学 计算生物学
- 结构生物学 结构生物学
背景情况:
- 膜蛋白的结构和动态对环境因素如pH敏感.
- pH值的变化改变了可电离残留物的质子化状态,影响了蛋白质的静电性和稳定性.
- 恒定pH分子动力学 (CpHMD) 允许动态的质子交换,模拟pH对蛋白质的影响.
研究的目的:
- 研究pH值变化对β-2上腺素受体 (β2AR) 局部构造性行为的影响.
- 探索动态质子变化如何影响受体循环灵活性和通信通路.
主要方法:
- 应用常数pH分子动力学 (CpHMD) 在pH值6.5,7.0和8.0时.
- 进行了常规分子动力学 (MD) 测试,以固定质子状态进行比较.
- 通过相互信息分析分析了循环灵活性,结合模式和受体区域之间的通信.
主要成果:
- 富含可定位残留物 (ICL3,ECL2) 的循环区域对pH值变化表现出最显著的反应.
- CpHMD揭示了循环灵活性和键的pH依赖的再分配,与固定质子模拟中的受约束行为不同.
- 关键GPCR微开关仍然处于不活跃状态,表明pH主要影响局部循环动态.
结论:
- 值变化通过质子状态的变化调节β-2上腺素受体 (β2AR) 的局部动力学和灵活性.
- 在不同的pH条件下观察到细胞外和细胞内环路之间的通信发生变化.
- 在分子模拟中纳入pH效应对于理解GPCR行为至关重要.
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