Biology:KCNN4

Short description: Protein-coding gene in the species Homo sapiens

Generic protein structure example

Potassium intermediate/small conductance calcium-activated channel, subfamily N, member 4, also known as KCNN4, is a human gene encoding the K_Ca3.1 protein.

Function

The K_Ca3.1 protein is part of a potentially heterotetrameric voltage-independent potassium channel that is activated by intracellular calcium. Activation is followed by membrane hyperpolarization, which promotes calcium influx. The encoded protein may be part of the predominant calcium-activated potassium channel in T-lymphocytes. This gene is similar to other KCNN family potassium channel genes, but it differs enough to possibly be considered as part of a new subfamily.

History

The channel activity was first described in 1958 by György Gárdos in human erythrocytes. The channel is also named Gardos channel because of its discoverer.

See also

• SK channel
• Voltage-gated potassium channel
• Senicapoc

Further reading

• "International Union of Pharmacology. LII. Nomenclature and molecular relationships of calcium-activated potassium channels". Pharmacol. Rev. 57 (4): 463–72. 2005. doi:10.1124/pr.57.4.9. PMID 16382103. 
• "A human intermediate conductance calcium-activated potassium channel". Proc. Natl. Acad. Sci. U.S.A. 94 (21): 11651–6. 1997. doi:10.1073/pnas.94.21.11651. PMID 9326665. Bibcode: 1997PNAS...9411651I. 
• "hSK4, a member of a novel subfamily of calcium-activated potassium channels". Proc. Natl. Acad. Sci. U.S.A. 94 (20): 11013–8. 1997. doi:10.1073/pnas.94.20.11013. PMID 9380751. Bibcode: 1997PNAS...9411013J. 
• "A novel gene, hKCa4, encodes the calcium-activated potassium channel in human T lymphocytes". J. Biol. Chem. 272 (52): 32723–6. 1997. doi:10.1074/jbc.272.52.32723. PMID 9407042. 
• "Human calcium-activated potassium channel gene KCNN4 maps to chromosome 19q13.2 in the region deleted in diamond-blackfan anemia". Genomics 51 (1): 160–1. 1998. doi:10.1006/geno.1998.5333. PMID 9693050. 
• "Calmodulin mediates calcium-dependent activation of the intermediate conductance KCa channel, IKCa1". J. Biol. Chem. 274 (9): 5746–54. 1999. doi:10.1074/jbc.274.9.5746. PMID 10026195. 
• "HIV-1 gp120 and chemokines activate ion channels in primary macrophages through CCR5 and CXCR4 stimulation". Proc. Natl. Acad. Sci. U.S.A. 97 (9): 4832–7. 2000. doi:10.1073/pnas.090521697. PMID 10758170. Bibcode: 2000PNAS...97.4832L. 
• "Up-regulation of the IKCa1 potassium channel during T-cell activation. Molecular mechanism and functional consequences". J. Biol. Chem. 275 (47): 37137–49. 2000. doi:10.1074/jbc.M003941200. PMID 10961988. 
• "Design of a potent and selective inhibitor of the intermediate-conductance Ca2+-activated K+ channel, IKCa1: a potential immunosuppressant". Proc. Natl. Acad. Sci. U.S.A. 97 (14): 8151–6. 2000. doi:10.1073/pnas.97.14.8151. PMID 10884437. Bibcode: 2000PNAS...97.8151W. 
• "Delineation of the clotrimazole/TRAM-34 binding site on the intermediate conductance calcium-activated potassium channel, IKCa1". J. Biol. Chem. 276 (34): 32040–5. 2001. doi:10.1074/jbc.M105231200. PMID 11425865. 
• "Unexpected down-regulation of the hIK1 Ca2+-activated K+ channel by its opener 1-ethyl-2-benzimidazolinone in HaCaT keratinocytes. Inverse effects on cell growth and proliferation". J. Biol. Chem. 278 (5): 3323–30. 2003. doi:10.1074/jbc.M208914200. PMID 12421833. 
• "Calcium-activated potassium channel expression in human myometrium: effect of pregnancy". Proc. West. Pharmacol. Soc. 45: 184–6. 2002. PMID 12434576. 
• "Trafficking of the Ca2+-activated K+ channel, hIK1, is dependent upon a C-terminal leucine zipper". J. Biol. Chem. 278 (10): 8476–86. 2003. doi:10.1074/jbc.M210072200. PMID 12493744. 
• "Molecular localization of the inhibitory arachidonic acid binding site to the pore of hIK1". J. Biol. Chem. 278 (19): 16690–7. 2003. doi:10.1074/jbc.M212959200. PMID 12609997. 
• "Modulation of Ca2+-activated Cl- secretion by basolateral K+ channels in human normal and cystic fibrosis airway epithelia". Pediatr. Res. 53 (4): 608–18. 2003. doi:10.1203/01.PDR.0000057204.51420.DC. PMID 12612194. 
• "The hSK4 (KCNN4) isoform is the Ca2+-activated K+ channel (Gardos channel) in human red blood cells". Proc. Natl. Acad. Sci. U.S.A. 100 (12): 7366–71. 2003. doi:10.1073/pnas.1232342100. PMID 12773623. Bibcode: 2003PNAS..100.7366H. 
• "Modulation of calcium-dependent chloride secretion by basolateral SK4-like channels in a human bronchial cell line". J. Membr. Biol. 196 (1): 15–31. 2003. doi:10.1007/s00232-003-0621-3. PMID 14724753. 
• "Blockade of the intermediate-conductance calcium-activated potassium channel as a new therapeutic strategy for restenosis". Circulation 108 (9): 1119–25. 2003. doi:10.1161/01.CIR.0000086464.04719.DD. PMID 12939222. 
• "The intermediate-conductance calcium-activated potassium channel KCa3.1 contributes to atherogenesis in mice and humans". J. Clin. Invest. 118 (9): 3025–37. 2008. doi:10.1172/JCI30836. PMID 18688283. 
• "Role of the NH2 terminus in the assembly and trafficking of the intermediate conductance Ca2+-activated K+ channel hIK1". J. Biol. Chem. 279 (15): 15531–40. 2004. doi:10.1074/jbc.M400069200. PMID 14754884. 
• "Modulation of Gardos channel activity by oxidants and oxygen tension: effects of 1-chloro-2,4-dinitrobenzene and phenazine methosulphate". Bioelectrochemistry 62 (2): 147–52. 2004. doi:10.1016/j.bioelechem.2003.07.008. PMID 15039018. 
• "Distribution of dehydration rates generated by maximal Gardos-channel activation in normal and sickle red blood cells". Blood 105 (1): 361–7. 2005. doi:10.1182/blood-2004-01-0125. PMID 15339840. 

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