GPCRarrestin
GPCRarrestin refers to the interaction between G protein-coupled receptors (GPCRs) and arrestin proteins, a critical regulatory mechanism in cellular signaling pathways. GPCRs are a large family of membrane proteins that transduce extracellular signals—such as hormones, neurotransmitters, and light—to intracellular responses. Upon activation by their ligands, GPCRs initially stimulate G proteins to propagate signals, but prolonged or excessive stimulation can lead to desensitization, a process where the receptor becomes less responsive.
Arrestins are cytosolic adaptor proteins that play a pivotal role in this desensitization. There are four known
Beyond desensitization, arrestin binding also facilitates receptor internalization through clathrin-mediated endocytosis, directing the receptor to lysosomes
The GPCR-arrestin interaction is dynamically regulated, with dephosphorylation of the receptor and arrestin dissociation allowing for