κ-opioid receptor

OPRK1
Available structures
PDB	Ortholog search: PDBe RCSB
List of PDB id codes
	4DJH
Identifiers
Aliases	OPRK1, K-OR-1, KOR, KOR-1, OPRK, opioid receptor kappa 1, KOR1, KOP
External IDs	OMIM: 165196; MGI: 97439; HomoloGene: 20253; GeneCards: OPRK1; OMA:OPRK1 - orthologs
Gene location (Human)
Chr.	Chromosome 8 (human)
End	53,251,637 bp
Gene location (Mouse)
Chr.	Chromosome 1 (mouse)
End	5,676,354 bp
RNA expression pattern
	Top expressed in
	endothelial cell; ; pons; ; lateral nuclear group of thalamus; ; testicle; ; Brodmann area 23; ; entorhinal cortex; ; middle temporal gyrus; ; nucleus accumbens; ; spinal ganglia; ; prefrontal cortex;
	Top expressed in
	decidua basalis; ; arachnoid mater; ; gastrula; ; superior frontal gyrus; ; wall of uterus; ; lumbar subsegment of spinal cord; ; embryo; ; submandibular gland; ; embryo; ; endometrium;
	More reference expression data
	More reference expression data
Gene ontology
Molecular function	G protein-coupled receptor activity; neuropeptide binding; signal transducer activity; G protein-coupled opioid receptor activity; protein binding; dynorphin receptor activity; receptor serine/threonine kinase binding; peptide binding;
Cellular component	axon terminus; integral component of membrane; perikaryon; membrane; synapse; integral component of plasma membrane; soma; dendrite; neuron projection; nucleus; cytosol; plasma membrane; integral component of synaptic vesicle membrane; integral component of postsynaptic membrane; integral component of presynaptic membrane;
Biological process	positive regulation of p38MAPK cascade; response to cocaine; negative regulation of luteinizing hormone secretion; adenylate cyclase-inhibiting G protein-coupled receptor signaling pathway; sensory perception; regulation of sensory perception of pain; eating behavior; locomotory behavior; behavioral response to cocaine; sensory perception of temperature stimulus; estrous cycle; conditioned place preference; response to estrogen; response to insulin; phospholipase C-activating G protein-coupled receptor signaling pathway; response to morphine; regulation of saliva secretion; positive regulation of dopamine secretion; G protein-coupled opioid receptor signaling pathway; defense response to virus; Maternal behavior; immune response; response to acrylamide; positive regulation of potassium ion transmembrane transport; sensory perception of pain; response to radiation; response to ethanol; neuropeptide signaling pathway; cellular response to lipopolysaccharide; positive regulation of locomotion; signal transduction; adenylate cyclase-inhibiting opioid receptor signaling pathway; chemical synaptic transmission; G protein-coupled receptor signaling pathway; animal behavior; positive regulation of eating behavior; cellular response to glucose stimulus;
	Sources:Amigo / QuickGO
Orthologs
	4986
	18387
	ENSG00000082556
	ENSMUSG00000025905
	P41145
	P33534
	NM_001282904; NM_000912; NM_001318497
	NM_001204371; NM_011011; NM_001318735
	NP_000903; NP_001269833; NP_001305426
	NP_001191300; NP_001305664; NP_035141
	Wikidata
View/Edit Human	View/Edit Mouse

The κ-opioid receptor or kappa opioid receptor, abbreviated KOR or KOP for its ligand ketazocine, is a G protein-coupled receptor that in humans is encoded by the OPRK1 gene. The KOR is coupled to the G protein G_i/G₀ and is among related receptors that bind opioid-like compounds in the brain and are responsible for mediating the effects of these compounds. These include altering nociception, mood, reward system, and motor control.

KOR is one of the two opioid receptors that bind dynorphin opioid peptides as the primary endogenous ligands, the other being newly deorphanized GPR139 receptor. In addition, oxytocin was found to be a positive allosteric modulator of KOR, and a variety of natural alkaloids, terpenes and synthetic ligands bind to the receptor.

Dysregulation of this receptor system has been implicated in multiple psychiatric disorders including: depressive and anxiety disorders, disorders of diminished motivation, schizophrenia, borderline personality disorder, bipolar disorder, substance use disorder.

Ligands binding to the receptor have been approved the treatment of pruritus and pain management. Aside from those indications they are investigated for various psychiatric disorders, irritable bowel syndrome, and acute stroke.