KCNJ5
G protein-activated inward rectifier potassium channel 4
Also known as: CIR, GIRK4, KATP1, KCNJ5_HUMAN, Kir3.4, LQT13
Cross-references: UniProt · Ensembl · Human Protein Atlas · GeneCards · NCBI Gene
Protein identityUniProt · HPA
- UniProt accession
- P48544
- Gene
- KCNJ5
- Ensembl
- ENSG00000120457
- Chromosome
- 11
- Canonical length
- 419 aa
- Protein class
- Cancer-related genes, Disease related genes, Human disease related genes, Potential drug targets, Predicted membrane proteins, Transporters, Voltage-gated ion channels
OverviewNCBI Gene
This gene encodes an integral membrane protein which belongs to one of seven subfamilies of inward-rectifier potassium channel proteins called potassium channel subfamily J. The encoded protein is a subunit of the potassium channel which is homotetrameric. It is controlled by G-proteins and has a greater tendency to allow potassium to flow into a cell rather than out of a cell. Naturally occurring mutations in this gene are associated with aldosterone-producing adenomas. [provided by RefSeq, Aug 2017]
Canonical amino-acid sequenceUniProt
419 residues, UniProt reviewed canonical sequence.
>P48544|KCNJ5
1 MAGDSRNAMN QDMEIGVTPW DPKKIPKQAR DYVPIATDRT RLLAEGKKPR QRYMEKSGKC
61 NVHHGNVQET YRYLSDLFTT LVDLKWRFNL LVFTMVYTVT WLFFGFIWWL IAYIRGDLDH
121 VGDQEWIPCV ENLSGFVSAF LFSIETETTI GYGFRVITEK CPEGIILLLV QAILGSIVNA
181 FMVGCMFVKI SQPKKRAETL MFSNNAVISM RDEKLCLMFR VGDLRNSHIV EASIRAKLIK
241 SRQTKEGEFI PLNQTDINVG FDTGDDRLFL VSPLIISHEI NQKSPFWEMS QAQLHQEEFE
301 VVVILEGMVE ATGMTCQARS SYMDTEVLWG HRFTPVLTLE KGFYEVDYNT FHDTYETNTP
361 SCCAKELAEM KREGRLLQYL PSPPLLGGCA EAGLDAEAEQ NEEDEPKGLG GSREARGSVLocalizationUniProt · AlphaFold · HPA
Whether an antibody against KCNJ5 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)
- 0.41
- Highest tissue expression
- 61 nTPM
Expression across tissuesHPA
Tissue
- adrenal gland: 61 nTPM
- pancreas: 19 nTPM
- spleen: 13 nTPM
- pituitary gland: 12 nTPM
- seminal vesicle: 9.1 nTPM
- heart muscle: 8 nTPM
Single-cell type
- hofbauer cells: 134 nCPM
- adrenal cortex cells: 124 nCPM
- cardiomyocytes: 49 nCPM
- lactotrophs: 40 nCPM
- somatotrophs: 34 nCPM
- adrenal medulla cells: 32 nCPM
Immune cell
- basophil: 0.5 nTPM
- neutrophil: 0.4 nTPM
- classical monocyte: 0.1 nTPM
- eosinophil: 0.1 nTPM
- naive B-cell: 0.1 nTPM
- total PBMC: 0.1 nTPM
Brain region
- hypothalamus: 20 nTPM
- thalamus: 11 nTPM
- white matter: 11 nTPM
- medulla oblongata: 10 nTPM
- pons: 8.3 nTPM
- cerebral cortex: 6.6 nTPM
DiseaseUniProt · ClinVar · IEDB · PubMed
Four sources answering four different questions about KCNJ5.
Disease | AllUniProt
Conditions KCNJ5 is implicated in, by any mechanism.
- Long QT syndrome 13 (LQT13) MIM:613485
- Hyperaldosteronism, familial, 3 (HALD3) MIM:613677
Disease | GeneticClinVar
8 pathogenic / likely-pathogenic of 525 ClinVar records.
Conditions with pathogenic or likely-pathogenic variants.
- Familial hyperaldosteronism type III
- Long QT syndrome
- Aldosterone-producing adrenal adenoma, somatic
- Andersen Tawil syndrome
- Cardiovascular phenotype
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)
- 1.14
- gnomAD pLI
- 0
- gnomAD missense Z
- 1.33
- DepMap mean gene effect
- 0.15
- DepMap dependency class
- none
Cancer expressionTCGA
Across TCGA tumor cohorts, this protein is over-expressed in roughly 3% of surveyed tumor types (aggregate summary; per-cohort expression, alteration, and survival load in the interactive view).
OntologyGO
Biological processes
- membrane repolarization during atrial cardiac muscle cell action potential
- potassium ion import across plasma membrane
- potassium ion transmembrane transport
- potassium ion transport
- regulation of heart rate by cardiac conduction
- regulation of monoatomic ion transmembrane transport
- ventricular cardiac muscle cell membrane repolarization
Molecular functions
- G-protein activated inward rectifier potassium channel activity
- inward rectifier potassium channel activity
- voltage-gated potassium channel activity involved in atrial cardiac muscle cell action potential repolarization
- voltage-gated potassium channel activity involved in ventricular cardiac muscle cell action potential repolarization
Cellular components
Protein domainsUniProt · Pfam · InterPro
- Potassium channel, inwardly rectifying, Kir, cytoplasmic
- Immunoglobulin E-set
- Potassium channel, inwardly rectifying, Kir
- Potassium channel, inwardly rectifying, transmembrane domain
- Inward rectifier potassium channel, C-terminal
- Inward rectifier potassium channel transmembrane domain
- Inward rectifier potassium channel C-terminal domain
- Potassium channel, inwardly rectifying, Kir3.4
KeywordsUniProt
Antibody and autoantibody relevanceSeroatlas analysis
Seroatlas reads KCNJ5 as an antibody target. Whether an autoantibody or antibody against KCNJ5 could matter depends on whether native KCNJ5 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.
KCNJ5 is annotated at the cell surface, where native KCNJ5 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 KCNJ5 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.
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