PROKR1 (prokineticin receptor 1) is a G protein-coupled receptor that mediates diverse physiological functions through activation of Gq and Gs protein pathways 1. Upon ligand binding, PROKR1 activation triggers calcium mobilization, phosphoinositide turnover, and MAPK/ERK phosphorylation 2. In reproductive biology, PROKR1 plays critical roles during early pregnancy. PROKR1 is highly expressed in first-trimester decidua and placental tissue, where PROK1-PROKR1 signaling regulates implantation-related genes including COX-2, leukemia inhibitory factor, and interleukins 23. The receptor controls trophoblast invasion and placental vascular development, with dysregulation contributing to preeclampsia and intrauterine growth restriction 3. PROKR1 also participates in male reproductive development 4 and endometrial receptivity 5. In skeletal muscle, PROKR1 activation promotes oxidative fiber specification through CREB-mediated upregulation of NR4A2, enhancing mitochondrial biogenesis and metabolic function 6. PROKR1 signaling ameliorates insulin resistance by activating PI3K/AKT pathways and promoting GLUT4 translocation to the plasma membrane 1. Prokr1-deficient mice exhibit impaired glucose tolerance, reduced lean mass, and decreased exercise performance 6. During enteric nervous system development, PROKR1 expression in neural crest-derived precursors supports proliferation and differentiation, with sequence variants associated with Hirschsprung disease susceptibility 7.