The M channel is a slowly activating and deactivating potassium channel that plays a critical role in the regulation of neuronal excitability. The M channel is formed by the association of the protein encoded by this gene and one of two related proteins encoded by the KCNQ2 and KCNQ5 genes, both integral membrane proteins. M channel currents are inhibited by M1 muscarinic acetylcholine receptors and activated by retigabine, a novel anti-convulsant drug. Defects in this gene are a cause of benign familial neonatal convulsions type 2 (BFNC2), also known as epilepsy, benign neonatal type 2 (EBN2).[1]
↑Yus-Nájera, E; Muñoz A; Salvador N; Jensen B S; Rasmussen H B; Defelipe J; Villarroel A (2003). "Localization of KCNQ5 in the normal and epileptic human temporal neocortex and hippocampal formation". Neuroscience. United States. 120 (2): 353–64. doi:10.1016/S0306-4522(03)00321-X. ISSN0306-4522. PMID12890507.
Further reading
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Ryan SG, Wiznitzer M, Hollman C, et al. (1991). "Benign familial neonatal convulsions: evidence for clinical and genetic heterogeneity". Ann. Neurol. 29 (5): 469–73. doi:10.1002/ana.410290504. PMID1859177.
Charlier C, Singh NA, Ryan SG, et al. (1998). "A pore mutation in a novel KQT-like potassium channel gene in an idiopathic epilepsy family". Nat. Genet. 18 (1): 53–5. doi:10.1038/ng0198-53. PMID9425900.
Yang WP, Levesque PC, Little WA, et al. (1998). "Functional expression of two KvLQT1-related potassium channels responsible for an inherited idiopathic epilepsy". J. Biol. Chem. 273 (31): 19419–23. doi:10.1074/jbc.273.31.19419. PMID9677360.
Schroeder BC, Kubisch C, Stein V, Jentsch TJ (1999). "Moderate loss of function of cyclic-AMP-modulated KCNQ2/KCNQ3 K+ channels causes epilepsy". Nature. 396 (6712): 687–90. Bibcode:1998Natur.396..687S. doi:10.1038/25367. PMID9872318.
Kubisch C, Schroeder BC, Friedrich T, et al. (1999). "KCNQ4, a novel potassium channel expressed in sensory outer hair cells, is mutated in dominant deafness". Cell. 96 (3): 437–46. doi:10.1016/S0092-8674(00)80556-5. PMID10025409.
Selyanko AA, Hadley JK, Wood IC, et al. (1999). "Two types of K(+) channel subunit, Erg1 and KCNQ2/3, contribute to the M-like current in a mammalian neuronal cell". J. Neurosci. 19 (18): 7742–56. PMID10479678.
Shapiro MS, Roche JP, Kaftan EJ, et al. (2000). "Reconstitution of muscarinic modulation of the KCNQ2/KCNQ3 K(+) channels that underlie the neuronal M current". J. Neurosci. 20 (5): 1710–21. PMID10684873.
Rundfeldt C, Netzer R (2000). "The novel anticonvulsant retigabine activates M-currents in Chinese hamster ovary-cells tranfected with human KCNQ2/3 subunits". Neurosci. Lett. 282 (1–2): 73–6. doi:10.1016/S0304-3940(00)00866-1. PMID10713399.
Schwake M, Pusch M, Kharkovets T, Jentsch TJ (2000). "Surface expression and single channel properties of KCNQ2/KCNQ3, M-type K+ channels involved in epilepsy". J. Biol. Chem. 275 (18): 13343–8. doi:10.1074/jbc.275.18.13343. PMID10788442.
Main MJ, Cryan JE, Dupere JR, et al. (2000). "Modulation of KCNQ2/3 potassium channels by the novel anticonvulsant retigabine". Mol. Pharmacol. 58 (2): 253–62. PMID10908292.
Wickenden AD, Yu W, Zou A, et al. (2000). "Retigabine, a novel anti-convulsant, enhances activation of KCNQ2/Q3 potassium channels". Mol. Pharmacol. 58 (3): 591–600. PMID10953053.
Tinel N, Diochot S, Lauritzen I, et al. (2000). "M-type KCNQ2-KCNQ3 potassium channels are modulated by the KCNE2 subunit". FEBS Lett. 480 (2–3): 137–41. doi:10.1016/S0014-5793(00)01918-9. PMID11034315.
Yus-Najera E, Santana-Castro I, Villarroel A (2002). "The identification and characterization of a noncontinuous calmodulin-binding site in noninactivating voltage-dependent KCNQ potassium channels". J. Biol. Chem. 277 (32): 28545–53. doi:10.1074/jbc.M204130200. PMID12032157.