Seroatlas · Human Serome Atlas

OPRK1

Kappa-type opioid receptor

Also known as: KOR, OPRK, OPRK_HUMAN

Cross-references: UniProt · Ensembl · Human Protein Atlas · GeneCards · NCBI Gene

Protein identityUniProt · HPA

UniProt accession
P41145
Gene
OPRK1
Ensembl
ENSG00000082556
Chromosome
8
Canonical length
380 aa
Protein class
FDA approved drug targets, G-protein coupled receptors, Predicted membrane proteins, Transporters
Subcellular location
Nucleoplasm,Plasma membrane,Cytosol

OverviewNCBI Gene

This gene encodes an opioid receptor, which is a member of the 7 transmembrane-spanning G protein-coupled receptor family. It functions as a receptor for endogenous ligands, as well as a receptor for various synthetic opioids. Ligand binding results in inhibition of adenylate cyclase activity and neurotransmitter release. This opioid receptor plays a role in the perception of pain and mediating the hypolocomotor, analgesic and aversive actions of synthetic opioids. Variations in this gene have also been associated with alcohol dependence and opiate addiction. Alternatively spliced transcript variants encoding different isoforms have been found for this gene. A recent study provided evidence for translational readthrough in this gene, and expression of an additional C-terminally extended isoform via the use of an alternative in-frame translation termination codon. [provided by RefSeq, Dec 2017]

Canonical amino-acid sequenceUniProt

380 residues, UniProt reviewed canonical sequence.

>P41145|OPRK1
     1  MDSPIQIFRG EPGPTCAPSA CLPPNSSAWF PGWAEPDSNG SAGSEDAQLE PAHISPAIPV
    61  IITAVYSVVF VVGLVGNSLV MFVIIRYTKM KTATNIYIFN LALADALVTT TMPFQSTVYL
   121  MNSWPFGDVL CKIVISIDYY NMFTSIFTLT MMSVDRYIAV CHPVKALDFR TPLKAKIINI
   181  CIWLLSSSVG ISAIVLGGTK VREDVDVIEC SLQFPDDDYS WWDLFMKICV FIFAFVIPVL
   241  IIIVCYTLMI LRLKSVRLLS GSREKDRNLR RITRLVLVVV AVFVVCWTPI HIFILVEALG
   301  STSHSTAALS SYYFCIALGY TNSSLNPILY AFLDENFKRC FRDFCFPLKM RMERQSTSRV
   361  RNTVQDPAYL RDIDGMNKPV

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against OPRK1 can act on the native protein depends on physical access: surface and secreted proteins are reachable by circulating antibodies, intracellular proteins usually are not.

Antibody reachability
Cell surface
Secreted
No
Transmembrane segments
7
Mean surface accessibility (rSASA)
0.35
Highest tissue expression
3.8 nTPM

Expression across tissuesHPA

Tissue

  • basal ganglia: 3.8 nTPM
  • hypothalamus: 2.6 nTPM
  • cerebral cortex: 2 nTPM
  • amygdala: 1.9 nTPM
  • prostate: 1.5 nTPM
  • skeletal muscle: 1 nTPM

Single-cell type

  • prostatic glandular cells: 22 nCPM
  • other brain neurons: 17 nCPM
  • brain inhibitory neurons: 15 nCPM
  • extravillous trophoblasts: 14 nCPM
  • endometrial luminal cells: 13 nCPM
  • endometrial glandular cells: 9.6 nCPM

Immune cell

  • basophil: 0.1 nTPM
  • classical monocyte: 0 nTPM
  • eosinophil: 0 nTPM
  • gdT-cell: 0 nTPM
  • intermediate monocyte: 0 nTPM
  • MAIT T-cell: 0 nTPM

Brain region

  • cerebral cortex: 34 nTPM
  • amygdala: 19 nTPM
  • thalamus: 18 nTPM
  • medulla oblongata: 16 nTPM
  • basal ganglia: 16 nTPM
  • hypothalamus: 16 nTPM

Genetic constraint and essentialitygnomAD · DepMap

Does the body need this protein intact? Low LOEUF or a strong DepMap dependency means loss or blockade of the protein is likely to be felt.

gnomAD LOEUF (loss-of-function intolerance)
1.31
gnomAD pLI
0
gnomAD missense Z
0.46
DepMap mean gene effect
0.04
DepMap dependency class
none

Cancer expressionTCGA

Across TCGA tumor cohorts, this protein is over-expressed in roughly 4% of surveyed tumor types (aggregate summary; per-cohort expression, alteration, and survival load in the interactive view).

OntologyGO

Biological processes

Molecular functions

Cellular components

Protein domainsUniProt · Pfam · InterPro

KeywordsUniProt

InteractionsUniProt · HPA

Protein binding partners of OPRK1 in the human serome: UniProt-annotated complex subunits plus reported interactors. Each links to its own Seroatlas record.

Antibody and autoantibody relevanceSeroatlas analysis

Seroatlas reads OPRK1 as an antibody target. Whether an autoantibody or antibody against OPRK1 could matter depends on whether native OPRK1 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

OPRK1 is annotated at the cell surface, where native OPRK1 is exposed to circulating antibodies and is a prime autoantibody target that could block, deplete, or overstimulate it.

Annotation status

The present source text does not explicitly label OPRK1 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/OPRK1. Study-independent annotations aggregated from UniProt, Human Protein Atlas, PubMed, IEDB, Pfam, InterPro, Gene Ontology, AlphaFold, gnomAD, DepMap, ClinVar, TCGA. Catalog release seroatlas-reviewed-human-uniprot-20260313.

Seroatlas is the reference for exploring autoantibody and antibody serology at the human-protein level: the autoreactome and human serome, multiplex serology (HuProt, HuScan, VirScan, PhIP-Seq).

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