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 a related protein encoded by the KCNQ3 gene, 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 1 (BFNC), also known as epilepsy, benign neonatal type 1 (EBN1). At least five transcript variants encoding five different isoforms have been found for this gene.[5]
Ligands
ICA-069673: channel opener at KCNQ2/Q3, 20-fold selective over KCNQ3/Q5, no measurable activity against a panel of cardiac ion channels (hERG, Nav1.5, L type channels, and KCNQ1) and no activity on GABAA gated channels at 10 μM. A range of related benzamides exhibited activity, of which compound number 40 is shown here.[6]
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Biervert C, Steinlein OK (March 1999). "Structural and mutational analysis of KCNQ2, the major gene locus for benign familial neonatal convulsions". Human Genetics. 104 (3): 234–40. doi:10.1007/PL00008713. PMID10323247.
Rundfeldt C, Netzer R (March 2000). "The novel anticonvulsant retigabine activates M-currents in Chinese hamster ovary-cells tranfected with human KCNQ2/3 subunits". Neuroscience Letters. 282 (1–2): 73–6. doi:10.1016/S0304-3940(00)00866-1. PMID10713399.
Main MJ, Cryan JE, Dupere JR, Cox B, Clare JJ, Burbidge SA (August 2000). "Modulation of KCNQ2/3 potassium channels by the novel anticonvulsant retigabine". Molecular Pharmacology. 58 (2): 253–62. doi:10.1124/mol.58.2.253. PMID10908292.
Wickenden AD, Yu W, Zou A, Jegla T, Wagoner PK (September 2000). "Retigabine, a novel anti-convulsant, enhances activation of KCNQ2/Q3 potassium channels". Molecular Pharmacology. 58 (3): 591–600. doi:10.1124/mol.58.3.591. PMID10953053.
Tinel N, Diochot S, Lauritzen I, Barhanin J, Lazdunski M, Borsotto M (September 2000). "M-type KCNQ2-KCNQ3 potassium channels are modulated by the KCNE2 subunit". FEBS Letters. 480 (2–3): 137–41. doi:10.1016/S0014-5793(00)01918-9. PMID11034315.