G-protein-coupled receptors (GPCRs) relay numerous extracellular signals by triggering intracellular signaling through coupling with G proteins and arrestins. Recent breakthroughs in the structural determination of GPCRs and GPCR–transducer complexes represent important steps toward deciphering GPCR signal transduction at a molecular level. A full understanding of the molecular basis of GPCR-mediated signaling requires elucidation of the dynamics of receptors and their transducer complexes as well as their energy landscapes and conformational transition rates. Here, we summarize current insights into the structural plasticity of GPCR–G-protein and GPCR–arrestin complexes that underlies the regulation of the receptor’s intracellular signaling profile.

G 蛋白偶联受体 (GPCR) 通过与 G 蛋白和视紫红质抑制蛋白偶联触发细胞内信号传导，从而传递大量细胞外信号。最近在 GPCR 和 GPCR-转导复合物的结构测定方面取得的突破代表了在分子水平上破译 GPCR 信号转导的重要一步。要充分了解 GPCR 介导的信号传导的分子基础，需要阐明受体及其转导复合物的动力学及其能量景观和构象转变率。在这里，我们总结了目前对 GPCR-G 蛋白和 GPCR-arrestin 复合物结构可塑性的见解，这些复合物是受体细胞内信号传导谱调控的基础。