阐明了对质子感应GPR68受体的激活机制
Christos Matsingos1, Lesley A Howell1, Peter J McCormick2
1Department of Chemistry, School of Physical and Chemical Sciences, Queen Mary University of London, London E1 4NS, United Kingdom.
Journal of molecular biology
|June 27, 2024
概括
一个质子感应受体GPR68在质子化时经历了部分激活. 模拟显示了关键的残留物相互作用和一种新的疏水性锁定,稳定了其非活性状态.
科学领域:
- 生物化学 生物化学
- 分子生物学分子生物学
- 药理学 药理学是指药理学的学科.
背景情况:
- GPR68是一种质子感应的G蛋白合受体 (GPCR),涉及生理过程和疾病,包括癌症.
- 通过细胞外pH值变化激活GPR68的精确分子机制在很大程度上仍未确定.
研究的目的:
- 使用多学科的计算和体外方法阐明GPR68的激活机制.
- 确定涉及GPR68质子感应和激活的关键残留物和结构特征.
主要方法:
- 对GPR68进行分子动力学 (MD) 模拟,以模拟pH诱导的变化.
- 在模拟过程中分析残留物相互作用,运动和pKa值.
- 序列分析和局部定向的突变发生,以调查残留物配对和结构元素.
主要成果:
- MD模拟显示了GPR68的全球和局部重组,与质子化时的部分激活一致.
- 细胞外的希斯蒂丁和跨膜酸性残留物呈现出上升的pKa值,支持它们在激活中的作用.
- 在细胞外区域发现并验证了一种新型的histidine-acidic残留的配对.
- 在细胞外区域发现了一种以前未被识别的疏水锁,可以稳定不活跃的GPR68形状.
结论:
- 特定残留物的质子化触发了GPR68.8的部分激活.
- 已识别的细胞外残留配对和疏水锁对于GPR68的结构稳定性和激活调节至关重要.
- 这些发现为GPR68功能在生理和病理上下文中的分子基础提供了新的见解.
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