When people say that something really gets my goat,â they mean that they are extremely irritated. A wide variety of things could contribute to irritation, ranging from someone else's actions to a series of events, but, despite the turn of phrase, goats are not usually involved.
The major activator of Rho family GTPase is GPCR (G-Protein coupled Receptor). GPCRs that activate Rho and use G-Alpha12 or G-Alpha13 for signal transduction include receptors for LPA (Lysophosphatidic Acid) and S-1P (Sphingosine 1-Phosphate) and certain Hormones. Besides GPCR, Itgs (Integrins) also activate Rho GTPase.
GPCRs associate with trimeric G-proteins (green), consisting of an alpha, beta, and gamma subunits. The subunits are tethered at the membrane surface by covalently attached lipid molecules. When a ligand binds, the receptor activates the attached G-protein by causing the exchange of GTP (yellow) for GDP (red).The activated G-protein then dissociates into an alpha (G-alpha) and a beta-gamma complex.ne type of G-alpha activates the enzyme adenylyl cyclase, which catalyzes the formation of the second messenger cyclic AMP (cAMP). Because an activated adenylyl cyclase can generate many molecules of cAMP, this is a means to amplify the signal.