GPR56/ADGRG1的G蛋白选择性概况及其对下游效应器的影响
Raida Jallouli1, Ana Lilia Moreno Salinas1, Andréanne Laniel1
1Université de Sherbrooke: Universite de Sherbrooke.
Research square
|September 16, 2024
概括
不同的GPR56配体通过不同的机制激活受体,影响癌细胞中的G蛋白选择性和Rho通路激活. 这一发现为研究GPR56活性及其在癌症中的作用提供了新的工具.
科学领域:
- 分子和细胞生物学分子和细胞生物学
- 生物化学 生物化学
- 药理学 药理学是指药理学的学科.
背景情况:
- GPR56是一种粘附性G蛋白结合受体 (aGPCR),表现出构成性和联结体促进活性.
- GPR56激活的基础分子机制及其在不同G蛋白中的功能选择性仍然不清楚.
- 了解GPR56激活对于其在包括癌症在内的生理和病理过程中的作用至关重要.
研究的目的:
- 为了调查GPR56的构成性和配体促进激活是否具有相同的分子机制.
- 为了确定不同的激活模式是否导致G蛋白之间的功能选择性.
- 通过使用特定的配体,探索GPR56激活在癌细胞中的作用.
主要方法:
- 使用了GPR56自保护性缺陷突变体 (GPR56-T383A) 和一个N端截断结构 (GPR56-Δ1-385).
- 用3a-acetoxydihydrodeoxygedunin (3αDOG) 和一种针对细胞外域 (ECD) 的新型抗体 (10C7) 刺激GPR56.
- 在各种细胞系统中评估了G蛋白 (G12/G13) 和β-arrestin招募,受体内化和Rho通路激活.
主要成果:
- 构成性地激活了G12和G13的GPR56.
- 抗体10C7优先激活G13而不是G12,独立于通过自催化裂变暴露的绑定激动剂 (TA).
- 与10C7激活不同的是,3αDOG的激活需要蛋白质分解,这表明了不同的连接体特定激活模式.
- 10C7和3αDOG都促进Rho通路的激活,10C7在BT-20乳腺癌细胞中显示出有效性.
结论:
- 不同的GPR56配体诱导不同的激活机制,导致不同的G蛋白选择性.
- 尽管G蛋白合不同,但GPR56激活在异质系统和内生癌细胞中都会汇聚在Rho通路上.
- 抗体10C7作为一个有价值的工具来剖析GPR56活动及其在癌症中的影响.
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