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]
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]
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]
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. doi:10.1016/S0169-328X(00)00204-7. PMID11042367.
Søgaard R, Ljungstrøm T, Pedersen KA, et al. (2001). "KCNQ4 channels expressed in mammalian cells: functional characteristics and pharmacology". Am. J. Physiol., Cell Physiol. 280 (4): C859–66. doi:10.1152/ajpcell.2001.280.4.C859. PMID11245603. S2CID7891527.
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.
Well, that’s interesting to know that Psilotum nudum are known as whisk ferns. Psilotum nudum is the commoner species of the two. While the P. flaccidum is a rare species and is found in the tropical islands. Both the species are usually epiphytic in habit and grow upon tree ferns. These species may also be terrestrial and grow in humus or in the crevices of the rocks.
View the detailed Guide of Psilotum nudum: Detailed Study Of Psilotum Nudum (Whisk Fern), Classification, Anatomy, Reproduction
Well, that’s interesting to know that Psilotum nudum are known as whisk ferns. Psilotum nudum is the commoner species of the two. While the P. flaccidum is a rare species and is found in the tropical islands. Both the species are usually epiphytic in habit and grow upon tree ferns. These species may also be terrestrial and grow in humus or in the crevices of the rocks.
View the detailed Guide of Psilotum nudum: Detailed Study Of Psilotum Nudum (Whisk Fern), Classification, Anatomy, Reproduction