Neuronal voltage-gated potassium channel (Kv channel)

Neuronal voltage-gated potassium channels (Kv channels) are tetrameric transmembrane proteins that selectively conduct potassium ions in response to membrane depolarization, playing a critical role in repolarizing neurons after action potentials to restore resting potential and regulate excitability.[1][2][3] Each subunit features six transmembrane helices (S1-S6), with the S4 segment acting as a voltage sensor containing conserved gating charges (arginines) that detect voltage changes and trigger conformational shifts to open or close the central pore formed by S5-S6 segments.[1][3] They exhibit diverse gating mechanisms, including activation at the bundle crossing, N-type inactivation via a "ball-and-chain" N-terminal domain, and C-type inactivation at the selectivity filter (TVGYG sequence).[1][3] In neurons, Kv channels control firing patterns, prevent hyperexcitability, and contribute to neurotransmitter release timing, with subfamilies like Kv1 (delayed rectifier), Kv3 (high-frequency firing), Kv4 (A-type transient), and Kv7 (M-current) showing specialized roles.[4][5][6][7] Dysfunctions or autoantibodies targeting Kv complexes link to diseases like epilepsy, ataxia, and Alzheimer's-related neuronal loss, while mutations alter excitability in neurodegenerative contexts.[1][4] Therapeutically, Kv modulators like blockers (e.g., 4-aminopyridine for multiple sclerosis) enhance conduction but risk seizures, whereas openers (e.g., ezogabine for epilepsy) suppress excitability with concerns for cardiac safety.[1][4][7]

Other names

Voltage-gated potassium channelVGKCKV channel

Potassium efflux to repolarize membrane after depolarization, Voltage-sensing via S4 segment leading to pore opening/closing, N-type and C-type inactivation to terminate conduction