β-arrestins bind active G protein-coupled receptors (GPCRs) and play a crucial role in receptor desensitization and internalization. The classical paradigm of arrestin function has been expanded with the identification of many non-receptor-binding partners, which indicated the multifunctional role of β-arrestins in cellular functions. To elucidate the molecular mechanism of β-arrestin-mediated signaling, the structural features of β-arrestins were investigated using X-ray crystallography and cryogenic electron microscopy (cryo-EM). However, the intrinsic conformational flexibility of β-arrestins hampers the elucidation of structural interactions between β-arrestins and their binding partners using conventional structure determination tools. Therefore, structural information obtained using complementary structure analysis techniques would be necessary in combination with X-ray crystallography and cryo-EM data. In this review, we describe how β-arrestins interact with their binding partners from a structural point of view, as elucidated by both traditional methods (X-ray crystallography and cryo-EM) and complementary structure analysis techniques.

β-arrestins结合活性G蛋白偶联受体（GPCR），并在受体脱敏和内在化过程中发挥关键作用。随着许多非受体结合伴侣的鉴定，抑制蛋白功能的经典范式得到了扩展，这表明了β-抑制蛋白在细胞功能中的多功能作用。为了阐明β-arrestin介导的信号传导的分子机制，使用X射线晶体学和低温电子显微镜（cryo-EM）研究了β-arrestin的结构特征。然而，β-arrestin的固有构象柔韧性阻碍了使用常规结构确定工具阐明β-arrestin与它们的结合伴侣之间的结构相互作用。因此，使用补充结构分析技术获得的结构信息将需要与X射线晶体学和低温EM数据结合使用。在这篇综述中，我们从结构的角度描述了β-arrestins如何与它们的结合伴侣相互作用，这是通过传统方法（X射线晶体学和cryo-EM）和互补结构分析技术所阐明的。