Gproteinini

Gproteinini, also known as G-protein-coupled receptors (GPCRs), are a large family of membrane-spanning proteins that function as receptors for a wide variety of signaling molecules, including hormones, neurotransmitters, and other extracellular ligands. They are named for their association with heterotrimeric G proteins, which are composed of three subunits: alpha, beta, and gamma. Upon ligand binding, GPCRs undergo a conformational change that activates the associated G protein, leading to the dissociation of the alpha subunit from the beta-gamma complex. The activated alpha subunit then interacts with downstream effectors, such as adenylate cyclase, phospholipase C, or ion channels, to initiate intracellular signaling pathways. GPCRs are involved in numerous physiological processes, including vision, olfaction, taste, and cardiovascular function. They are also important targets for many drugs, including those used to treat hypertension, asthma, and psychiatric disorders. The study of GPCRs has led to significant advancements in our understanding of cellular signaling and has provided valuable insights into the molecular mechanisms underlying various diseases.