prokineticin receptors, member of the class A family of seven-transmembrane G protein-coupled receptors
Prokineticins 1 (PROK1) and 2 (PROK2), also known as endocrine gland vascular endothelial factor and Bombina varigata 8, respectively, are multifunctional chemokine-like peptides that are highly conserved across species. Prokineticins can bind with similar affinities to two closely homologous 7-transmembrane G protein coupled receptors, PROKR1 and PROKR2, which are phylogenetically related to the tachykinin receptors. Prokineticins and their GPCRs are widely distributed in human tissues and are involved in numerous physiological roles, including gastrointestinal motility, generation of circadian rhythms, neuron migration and survival, pain sensation, angiogenesis, inflammation, and reproduction. Moreover, different point mutations in genes encoding PROK2 or its receptor (PROKR2) can lead to Kallmann syndrome, a disease characterized by delayed or absent puberty and impaired olfactory function.