PROK1 (prokineticin 1), also known as EG-VEGF, is a secreted 86-amino acid protein that regulates multiple physiological processes through binding to G-protein coupled receptors PROKR1 and PROKR2 1. PROK1 acts as a potent gastrointestinal smooth muscle contractile agent and promotes angiogenesis specifically in steroidogenic glands and reproductive organs 2. The protein activates complex signaling cascades including Gq-phospholipase C-β-cSrc-EGFR-MAPK/ERK pathways, leading to inositol phosphate mobilization and regulation of implantation-related genes such as COX-2, IL-6, IL-8, and leukemia inhibitory factor 3. PROK1 plays critical roles in human placentation by controlling trophoblast proliferation, survival, and invasion while promoting placental endothelial cell angiogenesis and permeability 1. The protein exhibits peak placental expression during early pregnancy before feto-maternal circulation establishment and is upregulated by hypoxia 1. Dysregulated PROK1 signaling contributes to pregnancy pathologies including preeclampsia and intrauterine growth restriction, with elevated serum levels observed in affected patients 4. A common genetic variant (V67I) acts as a disease modifier through downregulated gene expression while maintaining similar biological activities 5. PROKR2 antagonism shows therapeutic potential for preeclampsia treatment 6.