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.[1]
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.[2]
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