PAQR7 encodes membrane progesterone receptor α (mPRα), a plasma membrane-bound G protein-coupled receptor that mediates rapid, non-genomic progesterone signaling through Gi-mediated pathways 1. The receptor binds progesterone with high affinity (Kd = 4.6 nM) and also shows specificity for neurosteroids including allopregnanolone, pregnanolone, and dehydroepiandrosterone 2. PAQR7 functions primarily through PI3K-Akt and MAP kinase (ERK) signaling cascades while decreasing cAMP levels 13. The receptor plays critical roles in reproductive physiology, mediating anti-apoptotic effects in ovarian granulosa cells and supporting follicular development, with knockout mice showing prolonged estrous cycles, reduced fertility, and increased follicular atresia 4. In the nervous system, PAQR7 promotes neuronal survival and neurite outgrowth, demonstrating neuroprotective effects against Parkinson's disease-related toxins like 6-OHDA and MPP+ 35. Additionally, PAQR7 regulates vascular smooth muscle relaxation 1 and melanin synthesis in skin pigmentation 6. Aberrant PAQR7 expression is associated with various cancers, with overexpression correlating with poor prognosis in lung squamous cell carcinoma 7. The receptor's diverse physiological roles and disease associations make it a potential therapeutic target for reproductive disorders, neurodegenerative diseases, and certain cancers.