Upon their discovery, β-arrestins 1 and 2 were named for their capacity to sterically hinder
the G protein coupling of agonist-activated seven-transmembrane receptors, ultimately
resulting in receptor desensitization. Surprisingly, recent evidence shows that β-arrestins
can also function to activate signaling cascades independently of G protein activation. By
serving as multiprotein scaffolds, the β-arrestins bring elements of specific signaling
pathways into close proximity. β-Arrestin regulation has been demonstrated for an ever …