Arrestin

Function

Arrestin (ARR) is a ubiquitous protein which binds to the G protein-coupled receptor after its phosphorylation. ARR binding blocks further G protein-mediated signaling and redirects signaling to alternative non-G protein-independent pathways. Hence, ARR are versatile adaptor molecules which can also activate signaling cascades and are involved in nuclear functions.^[1]

Structural highlights

ARR consist of 2 domains. The N terminal domain structure is immunoglobulin-like. The binding site of phosphorylated light-activated rhodopsin is located at the N terminal of ARR.

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