Detecting the Role of Arrestins in G Protein-Coupled Receptor Regulation

G protein-coupled receptors (GPCRs) are the major sites of actions for the body’s endogenous hormones and neurotransmitters which make them ideal targets for pharmaceutical development with the goal of either mimicking the normal transmitter response or tempering it. In recent years, targeting GPCRs has become more complicated as we realize that drug action at receptors is “context dependent” such that activation and inhibition is limited to the response evaluated and agonist and antagonist become terms that reflect a particular condition of the experimental or physiological output. Therefore, the composition of the receptor’s immediate environment may determine activation profiles as posttranslational modifications of the receptor or of the binding partners can ultimately lead to regulation of the responsiveness of the receptor.