Beta-arrestin-2, or ARRB2, is an adaptor protein belonging to the arrestin family with an N- arrestin domain and a C- arrestin domain. ARRB2 is a regulatory protein involved in heterotrimeric G protein-coupled receptor desensitization and is known to regulate beta2-adrenergic receptor (beta2AR) function by enhancing beta2AR mediated nuclear translocation of ERK. ARRB2 binds to phosphorylated beta2ARs, thereby causing a significant impairment of their capacity to activate G(S) proteins. Along with AIP4, ARRB2 acts as an endosomal sorting molecule that mediates CXCR4 entry into a degradative pathway. It may also be involved in hormone-specific desensitization of TSH receptors. ARRB2 is a Ca2+ binding protein of the retinal outer segments and binds to P-rhodopsin and is also involved in synaptic transmission in photoreceptor cells. It is widely expressed in most of the tissues, especially neuronal tissues and spleen.
arrestin 3; Arrestin beta-2; arrestin, beta 2; arrestin-3; beta arr2; Beta-arrestin-2; beta-arrestin2; Non-visual arrestin-3; S-Arrestin