Glucagon receptor structures uncover new arrestin interaction mechanism

G protein-coupled receptors (GPCRs) are essential for cell signal transduction and constitute the largest drug target protein family. Upon agonist stimulation, these receptors activate multiple downstream transducers, including G proteins and arrestins, leading to distinct physiological functions. The arrestins play critical roles in modulating GPCR functionalities by terminating G protein signaling and promoting internalization.