人类P2X4受体门由稳定的细胞质盖和独特的全囊口袋调节
Haoyuan Shi1, Ismayn A Ditter1, Adam C Oken1
1Department of Chemical Physiology & Biochemistry, Oregon Health & Science University, Portland, OR 97239, USA.
Science advances
|January 17, 2025
概括
在ATP结合之前,P2X4受体的细胞质盖形成,影响脱敏率. 脂质稳定了这个帽子,像糖化和棕化这样的修改是P2X4功能的关键.
科学领域:
- 生物化学 生物化学
- 结构生物学 结构生物学
- 分子药理学分子药理学
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.
- 在P2XR亚型中,脱敏率有所不同,螺旋倒退模型表明细胞质盖稳定性决定了这一过程.
- 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受体脱敏的基础结构和功能机制.
- 确定细胞质盖在P2X4受体关门和脱敏感化动力学中的作用.
- 为了确定小分子调节器开发的潜在的全结位.
主要方法:
- 电子显微镜 (cryo-EM) 用于确定人类P2X4受体在多个功能状态中的结构.
- 功能性测试用于评估受体活性和脱敏动力学.
- 生物化学分析以调查翻译后的修改.
主要成果:
- 化EM结构显示了P2X4受体在阿波封闭状态,对抗体结合抑制状态和ATP结合脱敏状态的不同构造.
- 细胞质盖在非闭合和抑制状态下完好无损,但在无敏状态下不存在,表明了前激动剂结合形成.
- 脂质相互作用稳定了细胞质盖,调节了脱敏化;P2X4经历了糖化和棕化.
- 对抗体结合的结构突出显示了一种全性结合体结合口袋.
结论:
- 在ATP结合之前,P2X4受体的细胞质盖形成了ATP结合,在脱敏之前.
- 脂质相互作用和翻译后修改 (糖基化,棕化) 对P2X4受体功能和脱敏感性至关重要.
- 已确定的全结合部位为开发新型P2X4受体调节器提供了一个目标.
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