KCNA4

Potassium voltage-gated channel subfamily A member 4 also known as Kv1.4 is a is_associated_with::protein that in humans is encoded by the KCNA4 is_associated_with::gene. It contributes to the is_associated_with::cardiac transient outward potassium current (Ito1), the main contributing current to the repolarizing phase 1 of the cardiac action potential.

Description
KCNA4 (Kv1.4) contains a tandem inactivation domain at the is_associated_with::N terminus. It is composed of two subdomains. Inactivation domain 1 (ID1, residues 1-38) consists of a flexible N terminus anchored at a 5-turn helix, and is thought to work by occluding the ion pathway, as is the case with a classical ball domain. Inactivation domain 2 (ID2, residues 40-50) is a 2.5 turn helix with a high proportion of hydrophobic residues that probably serves to attach ID1 to the is_associated_with::cytoplasmic face of the channel. In this way, it can promote rapid access of ID1 to the receptor site in the open channel. ID1 and ID2 function together to bring about fast inactivation of the Kv1.4 channel, which is important for the role of the channel in short-term plasticity.

Interactions
KCNA4 has been shown to interact with is_associated_with::DLG4,   is_associated_with::KCNA2 and is_associated_with::DLG1.