FunctionPore-forming (alpha) subunit of voltage-gated rapidly inactivating A-type potassium channels. May contribute to I(To) current in heart and I(Sa) current in neurons. Channel properties are modulated by interactions with other alpha subunits and with regulatory subunits.
Tissue specificityWidely expressed. Highly expressed in brain, in particular in cerebellum and thalamus; detected at lower levels in the other parts of the brain.
Sequence similaritiesBelongs to the potassium channel family. D (Shal) (TC 1.A.1.2) subfamily. Kv4.1/KCND1 sub-subfamily.
DomainThe segment S4 is probably the voltage-sensor and is characterized by a series of positively charged amino acids at every third position.