Prokineticin receptor 2

Prokineticin receptor 2 (PKR₂), is a dimeric^[5] G protein-coupled receptor encoded by the PROKR2 gene in humans.^[6]

PROKR2
Identifiers
Aliases	PROKR2, GPR73L1, GPR73b, GPRg2, HH3, KAL3, PKR2, dJ680N4.3, prokineticin receptor 2
External IDs	OMIM: 607123; MGI: 2181363; HomoloGene: 16368; GeneCards: PROKR2; OMA:PROKR2 - orthologs
Gene location (Human) Chr. Chromosome 20 (human)[1] Band 20p12.3 Start 5,299,218 bp[1] End 5,316,954 bp[1]
Gene location (Mouse) Chr. Chromosome 2 (mouse)[2] Band 2|2 F2 Start 132,179,653 bp[2] End 132,227,367 bp[2]
RNA expression pattern Bgee Human Mouse (ortholog) Top expressed in ganglionic eminence ventricular zone prefrontal cortex Brodmann area 9 anterior cingulate cortex lymph node right frontal lobe bone marrow hippocampus proper superior frontal gyrus Top expressed in Rostral migratory stream lumbar spinal ganglion suprachiasmatic nucleus tail of embryo medial ganglionic eminence olfactory bulb Gonadal ridge thymus Sertoli cell anterior amygdaloid area More reference expression data BioGPS More reference expression data
Gene ontology Molecular function signal transducer activity neuropeptide Y receptor activity pancreatic polypeptide receptor activity G protein-coupled receptor activity Cellular component membrane integral component of membrane plasma membrane integral component of plasma membrane Biological process circadian rhythm signal transduction neuropeptide signaling pathway chemical synaptic transmission feeding behavior blood circulation G protein-coupled receptor signaling pathway Sources:Amigo / QuickGO
Orthologs Species Human Mouse Entrez 128674 246313 Ensembl ENSG00000101292 ENSMUSG00000050558 UniProt Q8NFJ6 Q8K458 RefSeq (mRNA) NM_144773 NM_144944 RefSeq (protein) NP_658986 NP_659193 Location (UCSC) Chr 20: 5.3 – 5.32 Mb Chr 2: 132.18 – 132.23 Mb PubMed search [3] [4]
Wikidata
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Function

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 PKR₂ mRNA fluctuate in the suprachiasmatic nucleus, increasing during the day and decreasing at night.^[7]

Mutations in the PROKR2 (also known as KAL3) gene have been implicated in hypogonadotropic hypogonadism and gynecomastia.^[8] Total loss of PKR₂ in mice leads to spontaneous torpor usually beginning at dusk and lasting for 8 hours on average.^[9]

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]

See also

• Prokineticin receptor
• Kallmann syndrome