偏向性细胞内激素的GPCR激活和GRK2组合
Jia Duan1,2,3, Heng Liu4, Fenghui Zhao5
1State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, China. duanjia@simm.ac.cn.
Nature
|August 2, 2023
概括
这项研究揭示了G蛋白合受体 (GPCR) 结合酶和偏向配体的结构. 这为理解GPCR-GRK相互作用和偏差信号提供了一个分子模型.
科学领域:
- 生物化学
- 分子生物学
- 药理学
背景情况:
- G-蛋白结合受体 (GPCR) 是参与许多生理过程的关键细胞表面受体.
- 通过GPCR激酶 (GRKs) 的酸化使GPCR变得无敏,并调解阿斯特林信号传递,这是受偏向配体影响的过程.
- 由于受体-激酶相互作用较弱,GRK与GPCR接触的精确分子机制和偏差信号传递仍然不明.
研究的目的:
- 阐明GPCR-GRK相互作用和GRK介导偏差信号的结构基础.
- 确定与GRK2,Gαq结合的神经素受体1 (NTSR1) 的复杂结构,以及与阿斯特林偏倚的SBI-553连接体.
主要方法:
- 使用冷电子显微镜报告了NTSR1,GRK2,Gαq和SBI-553的复杂结构.
- 分析了复合体内的结合界面和分子排列.
主要成果:
- 发现完整的GRK2结构与NTSR1的开放口袋挂,
- 通过稳定受体-激酶界面的复合物,证明了阿雷斯偏差配体SBI-553增强了GRK2结合.
- 显示SBI-553的结合模式有利于arrestin参与,同时阻碍了Gαq结合,解释了它的偏向信号.
结论:
- 确定的结构为GPCR-GRK相互作用提供了详细的分子模型.
- 为像SBI-553这样的联体驱动的GRK2介导偏差信号提供了一种机制性的解释.
- 突出了针对GPCR信号通路的基于结构的药物设计的潜力.
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