Potassium voltage-gated channel subfamily A member 4 (KCNA4)

Potassium voltage-gated channel subfamily A member 4 (KCNA4) is a tetrameric, voltage-gated potassium channel alpha-subunit belonging to the shaker-related (Kv) family, primarily forming rapidly inactivating A-type channels. These channels contribute to action potential repolarization and regulate membrane excitability in excitable cells such as neurons, cardiomyocytes, and muscle cells. By mediating potassium efflux following membrane depolarization, KCNA4 helps control the duration of action potentials, influences neurotransmitter release, and maintains normal cardiac rhythm. Genetic variants and dysfunction of KCNA4 have been implicated in rare neurodevelopmental and neuromuscular syndromes, as well as cardiac disorders. Pharmacological blockade of KCNA4—for example, by dalfampridine—prolongs action potentials and enhances synaptic transmission, an approach used therapeutically (e.g., in multiple sclerosis). However, such interference carries risks of seizures and arrhythmias due to the channel's critical physiological roles in both the nervous and cardiovascular systems

Other names

Kv1.4KCNA4LHK1HPCN2PCN2HUKIIHBK4Voltage-gated K(+) channel HuKIIVoltage-gated potassium channel HBK4Voltage-gated potassium channel HK1Voltage-gated potassium channel subunit Kv1.4Potassium channel 2Cardiac potassium channelFetal skeletal muscle potassium channelRapidly inactivating potassium channelShaker-related potassium channel Kv1.4Type A potassium channelMCIDDSKCNA8

Blockade of voltage-gated potassium channel to prolong action potential duration (notably by dalfampridine and 3,4-diaminopyridine)