Potassium voltage-gated channel subfamily Q member 2, 3, 4, and 5 (Kv7.2 (KCNQ2), Kv7.3 (KCNQ3), Kv7.4 (KCNQ4), Kv7.5 (KCNQ5))

Kv7.2, Kv7.3, Kv7.4, and Kv7.5 potassium channels are members of the voltage-gated potassium channel family encoded by the KCNQ2, KCNQ3, KCNQ4, and KCNQ5 genes, respectively. These channels are essential regulators of electrical excitability in neurons and smooth muscle, classically forming the M-channel when Kv7.2 and Kv7.3 assemble as heterotetramers in the nervous system[2][3][4]. They stabilize membrane potential by conducting K⁺ ions out of the cell in response to depolarization, thus opposing repetitive firing and hyperexcitability[1][8]. Mutations in these genes are linked to epilepsy and neurodevelopmental disorders, hearing loss, hypertension, and chronic pain, making them important therapeutic targets. Several drugs, such as retigabine and flupirtine, act as positive modulators, stabilizing the open state of the channels and reducing neuronal excitability, though some (notably retigabine) have significant adverse effects[5]. Selective modulators are in development for neuropsychiatric, cardiovascular, pain, and smooth muscle diseases[1][2][3][7].

Other names

M-channelKCNQ2KCNQ3KCNQ4KCNQ5Kv7 channelVoltage-gated potassium channel subunit Q2/Q3/Q4/Q5

Channel openers (positive modulators) increase potassium efflux, stabilizing membrane potential and suppressing excitability Negative modulators/inhibitors suppress channel function, increasing neuron or muscle excitability