National Natural Science Foundation of China (NSFC)
中国
引用
ジャーナル: Nature / 年: 2023 タイトル: GPCR activation and GRK2 assembly by a biased intracellular agonist. 著者: Jia Duan / Heng Liu / Fenghui Zhao / Qingning Yuan / Yujie Ji / Xiaoqing Cai / Xinheng He / Xinzhu Li / Junrui Li / Kai Wu / Tianyu Gao / Shengnan Zhu / Shi Lin / Ming-Wei Wang / Xi Cheng / ...著者: Jia Duan / Heng Liu / Fenghui Zhao / Qingning Yuan / Yujie Ji / Xiaoqing Cai / Xinheng He / Xinzhu Li / Junrui Li / Kai Wu / Tianyu Gao / Shengnan Zhu / Shi Lin / Ming-Wei Wang / Xi Cheng / Wanchao Yin / Yi Jiang / Dehua Yang / H Eric Xu / 要旨: Phosphorylation of G-protein-coupled receptors (GPCRs) by GPCR kinases (GRKs) desensitizes G-protein signalling and promotes arrestin signalling, which is also modulated by biased ligands. The ...Phosphorylation of G-protein-coupled receptors (GPCRs) by GPCR kinases (GRKs) desensitizes G-protein signalling and promotes arrestin signalling, which is also modulated by biased ligands. The molecular assembly of GRKs on GPCRs and the basis of GRK-mediated biased signalling remain largely unknown owing to the weak GPCR-GRK interactions. Here we report the complex structure of neurotensin receptor 1 (NTSR1) bound to GRK2, Gα and the arrestin-biased ligand SBI-553. The density map reveals the arrangement of the intact GRK2 with the receptor, with the N-terminal helix of GRK2 docking into the open cytoplasmic pocket formed by the outward movement of the receptor transmembrane helix 6, analogous to the binding of the G protein to the receptor. SBI-553 binds at the interface between GRK2 and NTSR1 to enhance GRK2 binding. The binding mode of SBI-553 is compatible with arrestin binding but clashes with the binding of Gα protein, thus providing a mechanism for its arrestin-biased signalling capability. In sum, our structure provides a rational model for understanding the details of GPCR-GRK interactions and GRK2-mediated biased signalling.