Prokineticins are secreted proteins that can promote angiogenesis and induce strong gastrointestinal smooth muscle contraction. The protein encoded by this gene is an integral membrane protein and G protein-coupled receptor for prokineticins. PKR2 is composed of 384 amino acids. Asparagine residues at position 7 and 27 undergo N-linked glycosylation.[5] Cysteine residues at position 128 and 208 form a disulfide bond.[5] The encoded protein is similar in sequence to GPR73, another G protein-coupled receptor for prokineticins.[6] PKR2 is also linked to mammalian circadian rhythm.[7] Levels of PKR2mRNA fluctuate in the suprachiasmatic nucleus, increasing during the day and decreasing at night.[7]
PKR2 functions as a G protein-coupled receptor, thus it has a signaling cascade when it's ligand binds. PKR2 is a Gq-coupled protein, so when the ligand binds, beta-type phospholipase C is activated which creates inositol triphosphate. This then triggers calcium release inside the cell.[10]
^ abMasumoto KH, Nagano M, Takashima N, Hayasaka N, Hiyama H, Matsumoto S, et al. (June 2006). "Distinct localization of prokineticin 2 and prokineticin receptor 2 mRNAs in the rat suprachiasmatic nucleus". The European Journal of Neuroscience. 23 (11): 2959–2970. doi:10.1111/j.1460-9568.2006.04834.x. PMID16819985. S2CID20510543.
Pasquali D, Rossi V, Staibano S, De Rosa G, Chieffi P, Prezioso D, et al. (September 2006). "The endocrine-gland-derived vascular endothelial growth factor (EG-VEGF)/prokineticin 1 and 2 and receptor expression in human prostate: Up-regulation of EG-VEGF/prokineticin 1 with malignancy". Endocrinology. 147 (9): 4245–4251. doi:10.1210/en.2006-0614. PMID16763065.
"Prokineticin Receptors: PKR2". IUPHAR Database of Receptors and Ion Channels. International Union of Basic and Clinical Pharmacology. Archived from the original on 2009-07-17. Retrieved 2008-12-09.