在葡萄糖受体上对阿斯特林的尾部接触
Kun Chen1,2, Chenhui Zhang1,2, Shuling Lin1
1State Key Laboratory of Drug Research, State Key Laboratory of Chemical Biology, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, China.
Nature
|August 9, 2023
概括
这项研究揭示了β-arrestin 1 (βarr1) 如何通过尾部与葡萄糖受体 (GCGR) 结合的独特结构见解. 这些发现澄清了对G蛋白结合受体 (GPCR) 的逮捕介导信号传递和受体贩运.
科学领域:
- 结构生物学
- 分子药理学
- 细胞信号传输
背景情况:
- 阿雷斯调节G蛋白合受体 (GPCR) 的信号传递和内化.
- 两种拟议的阿斯特林结合形状 (尾部和核心) 影响着不同的受体过程.
- 对于阿雷斯与受体的尾部接触存在有限的结构数据.
研究的目的:
- 在不同状态下确定β-arrestin 1 (βarr1) 与葡萄糖受体 (GCGR) 结合的结构基础.
- 阐明尾部参与结合模式在受体信号和贩运中的作用.
主要方法:
- 通过X射线结晶学确定与β-arrestin 1 (βarr1) 结合的两种葡萄糖受体结构 (GCGR).
- 分析了与尾部结合的βarr1-GCGR复合物的结构特征.
- 进行功能性研究以评估尾部形状在受体调节中的作用.
主要成果:
- 揭示了βarr1与GCGR的新型尾部结合方式,与之前观察到的相互作用不同.
- 在GCGR的Helix VIII和βarr1的中央之间发现了广泛的相互作用.
- 证明了一种酸衍生物稳定了βarr1-GCGR复合物.
- 显示受体核心保持不活跃和松散地与葡萄糖结合在尾部的状态.
- 确定尾部形状控制了βarr招募,GCGR内细胞和持续信号.
结论:
- arr1与GCGR的尾部结合涉及独特的结构特征,特别是与Helix VIII的相互作用.
- 这种结合模式对于调节受体膜招募,内细胞和细胞内信号来说至关重要.
- 为了解GPCR如何形成持续信号的超级复杂物提供了分子框架.
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