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]
- Arrestin-2 is regulator of B-cell function[2].
- Arrestin-3 assists in activation of JNK3 [3].
- Arrestin-4 or cone arrestin binds in a cone cell th G protein kinase to desensitise opsin.
- S-arrestin binds to photo activated Rho and terminates its signaling.
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.
3D Structures of arrestin
Arrestin 3D structures
