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. PKR2 is also linked to mammalian circadian rhythm. Levels of PKR2
mRNA fluctuate in the
suprachiasmatic nucleus, increasing during the day and decreasing at night. Total loss of PKR2 in mice leads to spontaneous
torpor usually beginning at dusk and lasting for 8 hours on average. 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. == See also ==