Regulation of mitogen-activated protein kinases by G-protein-coupled receptors

Abstract

A remarkably diverse array of stimuli, including growth factors, vasoactive polypeptides, chemoattractants, neurotransmitters, hormones, phospholipids, photons, odorants, and taste ligands, can elicit biological responses by stimulating receptors that transmit signals through the activation of heterotrimeric G proteins. The family of G-protein-coupled receptors (GPCRs) represents the largest group of cell surface receptors involved in signal transmission, and accounts for more than 1% of the total proteins encoded by the human genome. This large number of GPCRs, together with their ability to stimulate distinct Gα and βγ subunits and intracellular effector molecules, explains the remarkable complexity of the GPCR-G protein signal-transducing system.