KCNJ4

Inward rectifier potassium channel 4, also known as K_ir2.3, is a protein encoded in the human by the KCNJ4 gene.^[5]

KCNJ4
Available structures PDB Ortholog search: PDBe RCSB List of PDB id codes 3GJ9
Identifiers
Aliases	KCNJ4, HIR, HIRK2, HRK1, IRK-3, IRK3, Kir2.3, potassium voltage-gated channel subfamily J member 4, potassium inwardly rectifying channel subfamily J member 4
External IDs	OMIM: 600504; MGI: 104743; HomoloGene: 3653; GeneCards: KCNJ4; OMA:KCNJ4 - orthologs
Gene location (Human) Chr. Chromosome 22 (human)[1] Band 22q13.1 Start 38,426,327 bp[1] End 38,455,199 bp[1]
Gene location (Mouse) Chr. Chromosome 15 (mouse)[2] Band 15 E1|15 37.74 cM Start 79,367,915 bp[2] End 79,389,442 bp[2]
RNA expression pattern Bgee Human Mouse (ortholog) Top expressed in endothelial cell middle temporal gyrus Brodmann area 10 Brodmann area 23 frontal pole superior frontal gyrus postcentral gyrus Brodmann area 46 Region I of hippocampus proper entorhinal cortex Top expressed in superior frontal gyrus primary visual cortex perirhinal cortex dentate gyrus of hippocampal formation granule cell entorhinal cortex prefrontal cortex hippocampus proper nucleus accumbens CA3 field primary motor cortex More reference expression data BioGPS More reference expression data
Gene ontology Molecular function protein binding voltage-gated ion channel activity PDZ domain binding inward rectifier potassium channel activity G-protein activated inward rectifier potassium channel activity Cellular component synapse cytoplasmic vesicle membrane voltage-gated potassium channel complex cell junction integral component of membrane membrane cytoplasmic vesicle basolateral plasma membrane postsynaptic membrane plasma membrane Biological process regulation of ion transmembrane transport ion transport potassium ion transport potassium ion import across plasma membrane cardiac conduction Sources:Amigo / QuickGO
Orthologs Species Human Mouse Entrez 3761 16520 Ensembl ENSG00000168135 ENSMUSG00000044216 UniProt P48050 P52189 RefSeq (mRNA) NM_152868 NM_004981 NM_008427 RefSeq (protein) NP_004972 NP_690607 n/a Location (UCSC) Chr 22: 38.43 – 38.46 Mb Chr 15: 79.37 – 79.39 Mb PubMed search [3] [4]
Wikidata
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Function

Several different potassium channels are known to be involved with electrical signaling in the nervous system. One class is activated by depolarization whereas a second class is not. The latter are referred to as inwardly rectifying K+ channels, and they have a greater tendency to allow potassium to flow into the cell rather than out of it. This asymmetry in potassium ion conductance plays a key role in the excitability of muscle cells and neurons. The protein encoded by this gene is an integral membrane protein and member of the inward rectifier potassium channel family. The encoded protein has a small unitary conductance compared to other members of this protein family. Two transcript variants encoding the same protein have been found for this gene.^[5]

Interactions

KCNJ4 has been shown to interact with:

• CASK,^[6][7]
• DLG1^[6][7][8]
• DLG4,^[7][9][10]
• LIN7B,^[11] and
• LIN7C.^[6][7]

See also

• Inward-rectifier potassium ion channel