How and why do GPCRs dimerize?
Dimerization is fairly common in the G-protein-coupled receptor (GPCR) superfamily. First attempts to rationalize this phenomenon gave rise to an idea that two receptors in a dimer could be necessary to bind a single molecule of G protein or arrestin. Although GPCRs, G proteins and arrestins were crystallized only in their inactive conformations (in which they do not interact), the structures appeared temptingly compatible with this beautiful model. However, it did not survive the rigors of experimental testing: several recent studies unambiguously demonstrated that one receptor molecule is sufficient to activate a G protein and bind arrestin. Thus, to figure out the biological role of receptor self-association we must focus on other functions of GPCRs at different stages of their functional cycle.
Gurevich
Vsevolod V
VV
Department of Pharmacology, Vanderbilt University Medical Center, Nashville, TN 37232, USA. vsevolod.gurevich@vanderbilt.edu
Gurevich
Eugenia V
EV
D019281:Dimerization; D019204:GTP-Binding Proteins / Q000378:metabolism; D006801:Humans; D043562:Receptors, G-Protein-Coupled / Q000378:metabolism*; D015398:Signal Transduction
D043562:Receptors, G-Protein-Coupled; D019204:GTP-Binding Proteins