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Potassium inwardly-rectifying channel, subfamily J, member 4
Available structures
PDB Ortholog search: PDBe, RCSB
Symbols KCNJ4 ; HIR; HIRK2; HRK1; IRK-3; IRK3; Kir2.3
External IDs OMIM600504 MGI104743 HomoloGene3653 IUPHAR: Kir2.3 GeneCards: KCNJ4 Gene
RNA expression pattern
PBB GE KCNJ4 208359 s at tn.png
PBB GE KCNJ4 211451 s at tn.png
More reference expression data
Species Human Mouse
Entrez 3761 16520
Ensembl ENSG00000168135 ENSMUSG00000044216
UniProt P48050 P52189
RefSeq (mRNA) NM_004981 NM_008427
RefSeq (protein) NP_004972 NP_032453
Location (UCSC) Chr 22:
38.82 – 38.85 Mb
Chr 15:
79.48 – 79.51 Mb
PubMed search [1] [2]

Potassium inwardly-rectifying channel, subfamily J, member 4, also known as KCNJ4 or Kir2.3, is a human gene.[1]

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.[1]


KCNJ4 has been shown to interact with LIN7C,[2][3] LIN7B,[4] DLG4,[3][5][6] DLG1[2][3][7] and CASK.[2][3]

See also[edit]


  1. ^ a b "Entrez Gene: KCNJ4 potassium inwardly-rectifying channel, subfamily J, member 4". 
  2. ^ a b c Leonoudakis, Dmitri; Conti Lisa R; Anderson Scott; Radeke Carolyn M; McGuire Leah M M; Adams Marvin E; Froehner Stanley C; Yates John R; Vandenberg Carol A (May 2004). "Protein trafficking and anchoring complexes revealed by proteomic analysis of inward rectifier potassium channel (Kir2.x)-associated proteins". J. Biol. Chem. (United States) 279 (21): 22331–46. doi:10.1074/jbc.M400285200. ISSN 0021-9258. PMID 15024025. 
  3. ^ a b c d Leonoudakis, Dmitri; Conti Lisa R; Radeke Carolyn M; McGuire Leah M M; Vandenberg Carol A (April 2004). "A multiprotein trafficking complex composed of SAP97, CASK, Veli, and Mint1 is associated with inward rectifier Kir2 potassium channels". J. Biol. Chem. (United States) 279 (18): 19051–63. doi:10.1074/jbc.M400284200. ISSN 0021-9258. PMID 14960569. 
  4. ^ Olsen, Olav; Liu Hui; Wade James B; Merot Jean; Welling Paul A (January 2002). "Basolateral membrane expression of the Kir 2.3 channel is coordinated by PDZ interaction with Lin-7/CASK complex". Am. J. Physiol., Cell Physiol. (United States) 282 (1): C183–95. doi:10.1152/ajpcell.00249.2001. ISSN 0363-6143. PMID 11742811. 
  5. ^ Nehring, R B; Wischmeyer E; Döring F; Veh R W; Sheng M; Karschin A (January 2000). "Neuronal inwardly rectifying K(+) channels differentially couple to PDZ proteins of the PSD-95/SAP90 family". J. Neurosci. (United States) 20 (1): 156–62. PMID 10627592. 
  6. ^ Inanobe, Atsushi; Fujita Akikazu; Ito Minoru; Tomoike Hitonobu; Inageda Kiyoshi; Kurachi Yoshihisa (June 2002). "Inward rectifier K+ channel Kir2.3 is localized at the postsynaptic membrane of excitatory synapses". Am. J. Physiol., Cell Physiol. (United States) 282 (6): C1396–403. doi:10.1152/ajpcell.00615.2001. ISSN 0363-6143. PMID 11997254. 
  7. ^ Leonoudakis, D; Mailliard W; Wingerd K; Clegg D; Vandenberg C (March 2001). "Inward rectifier potassium channel Kir2.2 is associated with synapse-associated protein SAP97". J. Cell. Sci. (England) 114 (Pt 5): 987–98. ISSN 0021-9533. PMID 11181181. 

Further reading[edit]

External links[edit]

This article incorporates text from the United States National Library of Medicine, which is in the public domain.