Potassium voltage-gated channel subfamily KQT member 4, also known as voltage-gated potassium channel subunit Kv7.4, is a
protein that in humans is encoded by the KCNQ4gene.[5][6][7]
Function
The protein encoded by this gene forms a
potassium channel that is thought to play a critical role in the regulation of neuronal excitability, particularly in sensory cells of the
cochlea. The encoded protein can form a homomultimeric potassium channel or possibly a heteromultimeric channel in association with the protein encoded by the
KCNQ3 gene.[7]
Clinical significance
The current generated by this channel is inhibited by
muscarinic acetylcholine receptor M1 and activated by
retigabine, a novel anti-convulsant drug. Defects in this gene are a cause of
nonsyndromic sensorineural deafness type 2 (DFNA2), an autosomal dominant form of progressive hearing loss. Two transcript variants encoding different isoforms have been found for this gene.[7]
Van Hauwe P, Coucke PJ, Ensink RJ, et al. (2000). "Mutations in the KCNQ4 K+ channel gene, responsible for autosomal dominant hearing loss, cluster in the channel pore region". Am. J. Med. Genet. 93 (3): 184–7.
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10.1002/1096-8628(20000731)93:3<184::AID-AJMG4>3.0.CO;2-5.
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Beisel KW, Nelson NC, Delimont DC, Fritzsch B (2001). "Longitudinal gradients of KCNQ4 expression in spiral ganglion and cochlear hair cells correlate with progressive hearing loss in DFNA2". Brain Res. Mol. Brain Res. 82 (1–2): 137–49.
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doi:
10.1152/ajpcell.2001.280.4.C859.
PMID11245603.
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Stern RE, Lalwani AK (2003). "Audiologic evidence for further genetic heterogeneity at DFNA2". Acta Otolaryngol. 122 (7): 730–5.
doi:
10.1080/003655402/000028059.
PMID12484650.
Van Laer L, Carlsson PI, Ottschytsch N, et al. (2006). "The contribution of genes involved in potassium-recycling in the inner ear to noise-induced hearing loss". Hum. Mutat. 27 (8): 786–95.
doi:
10.1002/humu.20360.
PMID16823764.
S2CID25357017.
Van Eyken E, Van Laer L, Fransen E, et al. (2006). "KCNQ4: a gene for age-related hearing impairment?". Hum. Mutat. 27 (10): 1007–16.
doi:
10.1002/humu.20375.
PMID16917933.
S2CID8912727.
Su CC, Yang JJ, Shieh JC, et al. (2007). "Identification of novel mutations in the KCNQ4 gene of patients with nonsyndromic deafness from Taiwan". Audiol. Neurootol. 12 (1): 20–6.
doi:
10.1159/000096154.
PMID17033161.
S2CID25256223.
Iannotti FA, Panza E, Barrese V, Viggiano D, Soldovieri MV, Taglialatela M (March 2010). "Expression, localization, and pharmacological role of Kv7 potassium channels in skeletal muscle proliferation, differentiation, and survival after myotoxic insults". J. Pharmacol. Exp. Ther. 332 (3): 811–20.
doi:
10.1124/jpet.109.162800.
PMID20040580.
S2CID17248733.