通过细胞内激动剂激活B1类GPCR
Kazuhiro Kobayashi1, Kouki Kawakami2, Tsukasa Kusakizako1
1Department of Biological Sciences, Graduate School of Science, The University of Tokyo, Tokyo, Japan.
Nature
|June 7, 2023
概括
研究人员在G蛋白结合受体 (GPCR) 中发现了一种新的细胞内结合口袋. 这一发现揭示了偏向激动剂如何选择性地激活信号通路,为药物开发提供了新的途径.
科学领域:
- 结构生物学
- 药理学
- 生物化学
背景情况:
- G蛋白结合受体 (GPCRs) 通常在正体口袋中结合联体,触发构造变化并激活G蛋白和β-arrestin.
- 来自信号的不良影响需要了解选择性传感器激活.
- 在受体的细胞内空腔内结合的细胞内偏差激应剂最近对特定途径的信号产生了兴趣.
研究的目的:
- 阐明细胞内偏差激进的结构基础.
- 提供GPCR细胞内部激素结合的证据.
- 了解选择性G蛋白与β-arrestin激活的机制.
主要方法:
- 使用冷电子显微镜 (cryo-EM) 来确定复合物的结构.
- 该复合体由人甲状腺激素1型受体 (PTH1R),Gs和激动剂PCO371组成.
- 结构分析侧重于PCO371的结合方式及其对受体构成的影响.
主要成果:
- 结构显示,激动剂PCO371与细胞内PTH1R结合,直接与Gs相互作用.
- 这种结合诱导了无细胞外质信号传播的活性构造,稳定了跨膜螺旋6.
- PCO371通过与保留的细胞内口袋结合来激活15个B1类GPCR中的7个.
结论:
- 在GPCR中发现了一种新的和保存的细胞内激素结合口袋.
- 这项研究提供了针对受体-传感器接口的细胞内偏差激应的结构证据.
- 这种机制优先促进G蛋白结合而不是β- 停滞蛋白结合,为选择性药物开发提供了洞察力.
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