由压素2型受体的β-阿雷斯依赖和独立的内体G蛋白激活
Carole Daly1, Akim Abdul Guseinov2, Hyunggu Hahn3,4
1Wellcome-Wolfson Institute for Experimental Medicine, School of Medicine, Dentistry and Biomedical Sciences, Queen's University Belfast, Belfast, United Kingdom.
eLife
|October 19, 2023
概括
血管压素2型受体 (V2R) 通过与G蛋白和β-停滞蛋白相互作用,在内部化过程中维持信号传递. 这项研究揭示了V2R也在内分泌体中激活Gαq/11,挑战了当前G蛋白结合受体信号传递模型.
科学领域:
- 药理学 药理学是指药理学的学科.
- 细胞生物学 细胞生物学
- 分子生物学分子生物学
背景情况:
- 血管压素2型受体 (V2R) 对于水的恒温至关重要.
- V2R激活了Gαs和Gαq/11,招募了β-arrestins,并将其内部化为内分泌体.
- 规范性的G蛋白结合受体 (GPCR) 信号传输通常在β-逮捕素的招募和内部化时结束.
研究的目的:
- 研究Gαq/11在V2R内体信号传递中的作用.
- 为了确定β-arrestins是否强化或终止内体中的V2R G蛋白信号传递.
- 探索V2R内体G蛋白激活的β-arrestin依赖性. 为了探索V2R内体G蛋白激活的β-arrestin依赖性.
主要方法:
- 使用V2R表达细胞系统.
- 采用技术来评估G蛋白激活 (Gαs和Gαq/11) 在等离子体膜和内分泌体.
- 研究了β-arrestins在V2R内部化和信号传递中的作用.
主要成果:
- V2R与Gαs和Gαq/11共同定位并在内分泌体中发出信号.
- β-arrestins似乎增强,而不是终止,V2R G蛋白在内分泌体的信号传递.
- 微小程度的V2R介导的内体G蛋白激活独立于β-arrestins发生.
结论:
- 在内体中V2R信号传递涉及Gαs和Gαq/11.
- β-arrestins 增强了内体中的 V2R G 蛋白激活,与正规的 GPCR 模型有所不同.
- V2R内体信号传递可以通过β-止素依赖和β-止素独立的途径发生,因此需要对GPCR贩运和信号传递的理解进行修订.
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