The steroid progesterone induces the resumption of maturation in oocytes via a nongenomic pathway through binding to a novel, membrane progestin receptor (mPR). This pathway inhibits adenylyl cyclase and reduces intracellular cAMP, and also activates mitogen-activated protein kinase to effect signal transduction pathways. Three distinct groups, designated alpha, beta, and gamma, comprise this gene family. While all contain 7 transmembrane domains, they show distinct distributions in reproductive, neural, kidney and intestinal tissues. These characteristics separate them from nuclear progestin receptors, and instead imply similarity to G-protein coupled receptors.
Membrane progesterone P4 receptor gamma; Membrane progesterone receptor gamma; Membrane progestin receptor gamma; mPR gamma; MPRG; PAQR5; Progesterone and adipoQ receptor family member 5; Progestin and adipoQ receptor family member 5; Progestin and adipoQ receptor family member V