Membrane progesterone receptor (mPR) (mPR)

Membrane progesterone receptors (mPRs) are a group of cell surface receptors belonging to the progestin and adipoQ receptor (PAQR) family, distinct from the classical nuclear progesterone receptors (nPRs) [1, 12]. They mediate rapid, non-genomic actions of progesterone and its metabolites, such as allopregnanolone, which occur within minutes rather than hours [1, 11]. The family consists of five subtypes: mPRα (PAQR7), mPRβ (PAQR8), mPRγ (PAQR5), mPRδ (PAQR6), and mPRε (PAQR9) [1, 8]. These receptors are widely expressed in reproductive, neuroendocrine, and immune tissues, where they regulate processes like oocyte maturation, sperm motility, and neuroprotection [1, 11, 12]. In disease, mPRs are implicated in the progression of breast and ovarian cancers, as well as in neurological and inflammatory conditions [1, 2, 9]. Pharmacological targeting of mPRs with specific agonists like Org OD 02-0 is being explored for therapeutic potential in neuroprotection and cancer treatment, though challenges remain regarding their complex signaling crosstalk and structural characterization [11, 17, 19].

Other names

Progestin and adipoQ receptor familyPAQR familymPRαmPRβmPRγmPRδmPRεPAQR7PAQR8PAQR5PAQR6PAQR9

Activation of G proteins (primarily Gi/o) leading to modulation of intracellular cAMP levels and activation of MAPK/ERK and PI3K/Akt signaling pathways [1, 12, 15].