Arrestins comprise a family of closely-related proteins. In addition to the inactivation of G protein-coupled receptors, arrestins have been implicated in the endocytosis of receptors and cross talk with other signalling pathways. S-Arrestin (retinal S-antigen) is a major protein of the retinal rod outer segments. It interacts with photo-activated phosphorylated rhodopsin, inhibiting or 'arresting' … expand

Arrestins comprise a family of closely-related proteins. In addition to the inactivation of G protein-coupled receptors, arrestins have been implicated in the endocytosis of receptors and cross talk with other signalling pathways. S-Arrestin (retinal S-antigen) is a major protein of the retinal rod outer segments. It interacts with photo-activated phosphorylated rhodopsin, inhibiting or 'arresting' its ability to interact with transducin [ PUBMED:15335861 ]. Beta-arrestin-1 and -2, which regulate the function of beta-adrenergic receptors by binding to their phosphorylated forms, impairing their capacity to activate G(S) proteins; Cone photoreceptors C-arrestin (arrestin-X) [ PUBMED:7720881 ], which could bind to phosphorylated red/green opsins; and Drosophila phosrestins I and II, which undergo light-induced phosphorylation, and probably play a role in photoreceptor transduction [ PUBMED:8452755 PUBMED:1517224 PUBMED:2158671 ]. The crystal structure of bovine retinal arrestin comprises two domains of antiparallel β-sheets connected through a hinge region and one short α-helix on the back of the amino-terminal fold [ PUBMED:9495348 ].

This C-terminal domain consists of an immunoglobulin-like β-sandwich structure. This domain is found in arrestins and in other proteins including arrestin domain-containing proteins, protein ROD1 [ PUBMED:8621680 ] and ROG3 [ PUBMED:12163175 ] and thioredoxin-interacting protein [ PUBMED:17603038 ].