人类P2X4受体门由稳定的细胞质盖和独特的全囊口袋调节
bioRxiv : the preprint server for biology
|August 30, 2024
概括
在ATP结合之前,P2X4受体的细胞质盖形成,稳定通道以减缓脱敏. 脂质,糖化和棕化进一步调节P2X4受体功能.
科学领域:
- 生物物理学的生物物理.
- 分子生物学分子生物学
- 结构生物学 结构生物学
背景情况:
- P2X受体 (P2XRs) 是ATP导入的离子通道,对于细胞信号传输至关重要.
- 脱敏率在P2XR之间有所不同,受细胞质上的稳定性影响.
- 在缓慢无敏化的P2XR中细胞质盖形成的精确时间尚不清楚.
研究的目的:
- 阐明P2X4受体脱敏的结构基础.
- 确定细胞质盖在P2X4受体关门和脱敏感化动力学中的作用.
- 确定用于开发P2X4受体小分子调节器的结构特征.
主要方法:
- 全长的人类P2X4受体的冷电子显微镜 (冷EM).
- 结构分析的阿波,对手绑定,和无敏状态.
- 功能性测试用于评估受体活性和调制.
主要成果:
- 低温EM结构显示了P2X4受体在apo,对手结合和脱敏状态.
- 细胞质盖在阿波和对抗剂结合状态下完好无损,但在无敏状态下不存在,表明了前激动剂结合的形成.
- 脂质相互作用,糖化和棕化稳定了细胞质盖,减缓了脱敏.
- 对抗体结合的结构突出显示了一个全性联体结合口袋.
结论:
- P2X4受体的细胞质盖在激动剂结合之前形成,有助于缓慢脱敏.
- 脂质相互作用和翻译后修饰 (糖基化,棕化) 是稳定盖子和调节脱敏的关键.
- 对全结位的结构洞察力使得新型P2X4受体调节器的设计成为可能.
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