KCNJ5

G protein-activated inward rectifier potassium channel 4 (GIRK-4) is a protein that in humans is encoded by the KCNJ5 gene and is a type of G protein-gated ion channel.

KCNJ5
Identifiers
Aliases	KCNJ5, CIR, GIRK4, KATP1, KIR3.4, LQT13, potassium voltage-gated channel subfamily J member 5, potassium inwardly rectifying channel subfamily J member 5
External IDs	OMIM: 600734; MGI: 104755; HomoloGene: 20248; GeneCards: KCNJ5; OMA:KCNJ5 - orthologs
Gene location (Human) Chr. Chromosome 11 (human) Band 11q24.3 Start 128,891,356 bp End 128,921,163 bp
Gene location (Mouse) Chr. Chromosome 9 (mouse) Band 9 A4|9 17.65 cM Start 32,226,003 bp End 32,255,646 bp
RNA expression pattern Bgee Human Mouse (ortholog) Top expressed in buccal mucosa cell endothelial cell adrenal cortex right adrenal gland left adrenal gland left adrenal cortex right adrenal cortex tendon of biceps brachii right ventricle myocardium Top expressed in atrium atrioventricular valve aortic valve olfactory epithelium endocardial cushion right lobe of liver myocardium of ventricle supraoptic nucleus right ventricle embryo More reference expression data BioGPS n/a
Gene ontology Molecular function G-protein activated inward rectifier potassium channel activity protein binding inward rectifier potassium channel activity voltage-gated ion 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 component integral component of membrane T-tubule plasma membrane membrane external side of plasma membrane voltage-gated potassium channel complex Biological process potassium ion transport regulation of ion transmembrane transport ion transport regulation of heart rate by cardiac conduction membrane repolarization during atrial cardiac muscle cell action potential membrane repolarization during ventricular cardiac muscle cell action potential ventricular cardiac muscle cell membrane repolarization potassium ion import across plasma membrane Sources:Amigo / QuickGO
Orthologs Species Human Mouse Entrez 3762 16521 Ensembl ENSG00000120457 ENSMUSG00000032034 UniProt P48544 P48545 RefSeq (mRNA) NM_000890 NM_001354169 NM_010605 RefSeq (protein) NP_000881 NP_001341098 NP_034735 Location (UCSC) Chr 11: 128.89 – 128.92 Mb Chr 9: 32.23 – 32.26 Mb PubMed search
Wikidata
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Function

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. It may associate with other G-protein-activated potassium channel subunits to form a heterotetrameric pore-forming complex.

In humans KCNJ5 is mainly expressed in adrenal gland and pituitary, although it is also detected at low levels in pancreas, spleen, lung, heart and brain. Consistent with this expression pattern, mutations in KCNJ5/Kir3.4 can cause familial hyperaldosteronism type III and a type of long QT syndrome.

Interactions

KCNJ5 has been shown to interact with KCNJ3.

See also

• G protein-coupled inwardly-rectifying potassium channel
• Inward-rectifier potassium ion channel

Further reading

• Zhuo ML, Huang Y, Liu DP, Liang CC (April 2005). "KATP channel: relation with cell metabolism and role in the cardiovascular system". The International Journal of Biochemistry & Cell Biology. 37 (4): 751–64. doi:10.1016/j.biocel.2004.10.008. PMID 15694835.
• Tucker SJ, James MR, Adelman JP (July 1995). "Assignment of KATP-1, the cardiac ATP-sensitive potassium channel gene (KCNJ5), to human chromosome 11q24". Genomics. 28 (1): 127–8. doi:10.1006/geno.1995.1121. PMID 7590741.
• Ashford ML, Bond CT, Blair TA, Adelman JP (1996). "Cloning and functional expression of a rat heart KATP channel". Nature. 378 (6559): 792. doi:10.1038/378792a0. PMID 8524415.
• Spauschus A, Lentes KU, Wischmeyer E, Dissmann E, Karschin C, Karschin A (February 1996). "A G-protein-activated inwardly rectifying K+ channel (GIRK4) from human hippocampus associates with other GIRK channels". The Journal of Neuroscience. 16 (3): 930–8. doi:10.1523/JNEUROSCI.16-03-00930.1996. PMC 6578796. PMID 8558261.
• Iizuka M, Kubo Y, Tsunenari I, Pan CX, Akiba I, Kono T (1996). "Functional characterization and localization of a cardiac-type inwardly rectifying K+ channel". Receptors & Channels. 3 (4): 299–315. PMID 8834003.
• Chan KW, Langan MN, Sui JL, Kozak JA, Pabon A, Ladias JA, Logothetis DE (March 1996). "A recombinant inwardly rectifying potassium channel coupled to GTP-binding proteins". The Journal of General Physiology. 107 (3): 381–97. doi:10.1085/jgp.107.3.381. PMC 2216996. PMID 8868049.
• Huang CL, Jan YN, Jan LY (April 1997). "Binding of the G protein betagamma subunit to multiple regions of G protein-gated inward-rectifying K+ channels". FEBS Letters. 405 (3): 291–8. Bibcode:1997FEBSL.405..291H. doi:10.1016/S0014-5793(97)00197-X. PMID 9108307. S2CID 44072628.
• Kanzaki M, Lindorfer MA, Garrison JC, Kojima I (June 1997). "Activation of the calcium-permeable cation channel CD20 by alpha subunits of the Gi protein". The Journal of Biological Chemistry. 272 (23): 14733–9. doi:10.1074/jbc.272.23.14733. PMID 9169438.
• Wischmeyer E, Döring F, Wischmeyer E, Spauschus A, Thomzig A, Veh R, Karschin A (1997). "Subunit interactions in the assembly of neuronal Kir3.0 inwardly rectifying K+ channels". Molecular and Cellular Neurosciences. 9 (3): 194–206. doi:10.1006/mcne.1997.0614. PMID 9245502. S2CID 8455396.
• Krapivinsky G, Kennedy ME, Nemec J, Medina I, Krapivinsky L, Clapham DE (July 1998). "Gbeta binding to GIRK4 subunit is critical for G protein-gated K+ channel activation". The Journal of Biological Chemistry. 273 (27): 16946–52. doi:10.1074/jbc.273.27.16946. PMID 9642257.
• Corey S, Clapham DE (October 1998). "Identification of native atrial G-protein-regulated inwardly rectifying K+ (GIRK4) channel homomultimers". The Journal of Biological Chemistry. 273 (42): 27499–504. doi:10.1074/jbc.273.42.27499. PMID 9765280.
• Kennedy ME, Nemec J, Corey S, Wickman K, Clapham DE (January 1999). "GIRK4 confers appropriate processing and cell surface localization to G-protein-gated potassium channels". The Journal of Biological Chemistry. 274 (4): 2571–82. doi:10.1074/jbc.274.4.2571. PMID 9891030.
• Schoots O, Wilson JM, Ethier N, Bigras E, Hebert TE, Van Tol HH (December 1999). "Co-expression of human Kir3 subunits can yield channels with different functional properties". Cellular Signalling. 11 (12): 871–83. doi:10.1016/S0898-6568(99)00059-5. PMID 10659995.
• He C, Yan X, Zhang H, Mirshahi T, Jin T, Huang A, Logothetis DE (February 2002). "Identification of critical residues controlling G protein-gated inwardly rectifying K(+) channel activity through interactions with the beta gamma subunits of G proteins". The Journal of Biological Chemistry. 277 (8): 6088–96. doi:10.1074/jbc.M104851200. PMID 11741896.
• Ma D, Zerangue N, Raab-Graham K, Fried SR, Jan YN, Jan LY (February 2002). "Diverse trafficking patterns due to multiple traffic motifs in G protein-activated inwardly rectifying potassium channels from brain and heart". Neuron. 33 (5): 715–29. doi:10.1016/S0896-6273(02)00614-1. PMID 11879649. S2CID 10459917.
• Lavine N, Ethier N, Oak JN, Pei L, Liu F, Trieu P, Rebois RV, Bouvier M, Hebert TE, Van Tol HH (November 2002). "G protein-coupled receptors form stable complexes with inwardly rectifying potassium channels and adenylyl cyclase". The Journal of Biological Chemistry. 277 (48): 46010–9. doi:10.1074/jbc.M205035200. PMID 12297500.
• Shankar H, Murugappan S, Kim S, Jin J, Ding Z, Wickman K, Kunapuli SP (September 2004). "Role of G protein-gated inwardly rectifying potassium channels in P2Y12 receptor-mediated platelet functional responses". Blood. 104 (5): 1335–43. doi:10.1182/blood-2004-01-0069. PMID 15142872.

External links

• KCNJ5+protein,+human at the U.S. National Library of Medicine Medical Subject Headings (MeSH)
• GTEX portal: KCNJ5 expression in human tissue

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