Seroatlas · Human Serome Atlas

KCNJ8

ATP-sensitive inward rectifier potassium channel 8

Also known as: KCNJ8_HUMAN, Kir6.1

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

Protein identityUniProt · HPA

UniProt accession
Q15842
Gene
KCNJ8
Ensembl
ENSG00000121361
Chromosome
12
Canonical length
424 aa
Protein class
Disease related genes, FDA approved drug targets, Metabolic proteins, Predicted membrane proteins, Transporters, Voltage-gated ion channels

OverviewNCBI Gene

Potassium channels are present in most mammalian cells, where they participate in a wide range of physiologic responses. The protein encoded by this gene is an integral membrane protein and inward-rectifier type potassium channel. The encoded protein, which has a greater tendency to allow potassium to flow into a cell rather than out of a cell, is controlled by G-proteins. Defects in this gene may be a cause of J-wave syndromes and sudden infant death syndrome (SIDS). [provided by RefSeq, May 2012]

Canonical amino-acid sequenceUniProt

424 residues, UniProt reviewed canonical sequence.

>Q15842|KCNJ8
     1  MLARKSIIPE EYVLARIAAE NLRKPRIRDR LPKARFIAKS GACNLAHKNI REQGRFLQDI
    61  FTTLVDLKWR HTLVIFTMSF LCSWLLFAIM WWLVAFAHGD IYAYMEKSGM EKSGLESTVC
   121  VTNVRSFTSA FLFSIEVQVT IGFGGRMMTE ECPLAITVLI LQNIVGLIIN AVMLGCIFMK
   181  TAQAHRRAET LIFSRHAVIA VRNGKLCFMF RVGDLRKSMI ISASVRIQVV KKTTTPEGEV
   241  VPIHQLDIPV DNPIESNNIF LVAPLIICHV IDKRSPLYDI SATDLANQDL EVIVILEGVV
   301  ETTGITTQAR TSYIAEEIQW GHRFVSIVTE EEGVYSVDYS KFGNTVKVAA PRCSARELDE
   361  KPSILIQTLQ KSELSHQNSL RKRNSMRRNN SMRRNNSIRR NNSSLMVPKV QFMTPEGNQN
   421  TSES

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against KCNJ8 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
2
Mean surface accessibility (rSASA)
0.38
Highest tissue expression
64 nTPM

Expression across tissuesHPA

Tissue

  • heart muscle: 64 nTPM
  • pancreas: 37 nTPM
  • liver: 35 nTPM
  • adipose tissue: 27 nTPM
  • blood vessel: 21 nTPM
  • breast: 20 nTPM

Single-cell type

  • pericytes: 122 nCPM
  • breast lactating cells: 66 nCPM
  • cardiomyocytes: 62 nCPM
  • decidual stromal cells: 34 nCPM
  • alveolar cells type 2: 30 nCPM
  • pancreatic acinar cells: 28 nCPM

Immune cell

  • eosinophil: 1.5 nTPM
  • basophil: 0 nTPM
  • classical monocyte: 0 nTPM
  • gdT-cell: 0 nTPM
  • intermediate monocyte: 0 nTPM
  • MAIT T-cell: 0 nTPM

Brain region

  • choroid plexus: 19 nTPM
  • thalamus: 10 nTPM
  • basal ganglia: 6.1 nTPM
  • midbrain: 6 nTPM
  • medulla oblongata: 5.9 nTPM
  • spinal cord: 5.9 nTPM

DiseaseUniProt · ClinVar · IEDB · PubMed

Four sources answering four different questions about KCNJ8.

Disease | AllUniProt

Conditions KCNJ8 is implicated in, by any mechanism.

  • Sudden infant death syndrome (SIDS) MIM:272120
  • Hypertrichotic osteochondrodysplasia (HTOCD) MIM:239850

Disease | GeneticClinVar

2 pathogenic / likely-pathogenic of 288 ClinVar records.

Conditions with pathogenic or likely-pathogenic variants.

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)
0.57
gnomAD pLI
0.38
gnomAD missense Z
3.45
DepMap mean gene effect
0.08
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 KCNJ8 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 KCNJ8 as an antibody target. Whether an autoantibody or antibody against KCNJ8 could matter depends on whether native KCNJ8 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

KCNJ8 is annotated at the cell surface, where native KCNJ8 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 KCNJ8 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/KCNJ8. 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).

© 2026 · Seroatlas, Discover Oregon LLC · Terms of use

Loading the interactive Seroatlas protein explorer...