通过G蛋白结合受体识别阿雷斯的酸化代码
X Edward Zhou1, Yuanzheng He2, Parker W de Waal2
1VARI-SIMM Center, Center for Structure and Function of Drug Targets, CAS-Key Laboratory of Receptor Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China; Laboratory of Structural Sciences, Center for Structural Biology and Drug Discovery, Van Andel Research Institute, Grand Rapids, MI 49503, USA.
Cell
|July 29, 2017
概括
研究人员发现了化G蛋白结合受体 (GPCR) 如何与阿斯特林结合. 这一发现揭示了一种称为酸化代码的常见机制,用于阻止GPCRs的招募,影响细胞信号传输.
科学领域:
- 结构生物学
- 分子和细胞信号
背景情况:
- G蛋白结合受体 (GPCR) 是参与各种生理过程的关键细胞表面受体.
- 阿雷斯与GPCRs结合,调解受体脱敏,内化和G蛋白独立的信号通路.
- 高 afinity 的 arrestin 结合需要先前的 GPCR 化,通常在 C- 末尾.
研究的目的:
- 阐明化罗多和阿斯特林之间的相互作用的结构基础.
- 确定特定的化位点及其在阿斯特林结合中介作用.
- 建议使用GPCR进行酸化依赖性阻断的一般机制.
主要方法:
- 使用X射线自由电子激光 (XFEL) 结晶学来确定罗多普辛-阿雷斯复合物的结构.
- 生物化学分析用于识别和验证罗多素C终端尾部的酸化位.
- 分析了结构数据以了解控制复杂形成的静电相互作用.
主要成果:
- 晶体结构显示在化罗多C末端和阿雷斯N末端β链之间形成的延伸的分子间β片.
- 在素336 (T336) 和素338 (S338) 的酸化被确定为高亲和度结合的关键.
- 观察到阿雷斯中的这些基残留物和正电荷口袋之间的静电相互作用网络,类似于其他GPCR-阿雷斯相互作用.
- 一组"酸化代码"被推导出,解释了阿斯特林招募的共同机制.
结论:
- 这项研究提供了高分辨率的结构洞察力.
- 酸化是高 afinity arrestin 与 GPCR 结合的一个关键决定因素.
- 已识别的"酸化代码"代表了各种GPCR中停止招募的保存机制,影响细胞信号通路.
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