Potassium voltage-gated channel subfamily E member 4 (KCNE4)

Potassium voltage-gated channel subfamily E member 4 (KCNE4) is a single-pass transmembrane protein acting as an auxiliary (beta) subunit to voltage-gated potassium (Kv) channels[1][2][3][8]. It is encoded by the KCNE4 gene on chromosome 2 and can exist in short (KCNE4S) and long (KCNE4L) isoforms[2]. KCNE4 modulates the function of several Kv channel alpha subunits (e.g., KCNQ1, KCNQ4, Kv1.x, Kv2.1, Kv4.x, BK), typically inhibiting current or affecting channel surface expression and gating kinetics depending on the channel subtype and tissue context[1][2][3][8]. KCNE4 is expressed primarily in the uterus, heart, and select other tissues[2]. Its modulation of cardiac potassium channels is implicated in cardiac rhythm regulation, with a single known polymorphism (E145D) modestly associating with atrial fibrillation risk in humans[2]. The protein plays important roles in cardiovascular physiology, sex-dependent cardiac responses, and vascular tone regulation, with therapeutic targeting limited to a research context due to safety concerns regarding broad potassium channel modulation[2][3].

Other names

MinK-related peptide 3MiRP3Minimum potassium ion channel-related peptide 3Potassium channel subunit beta MiRP3Cardiac voltage-gated potassium channel accessory subunit 4Potassium voltage-gated channel, Isk-related family, member 4Potassium channel, voltage gated subfamily E regulatory beta subunit 4KCNE4L (long isoform)KCNE4S (short isoform)

Drugs targeting potassium channels act by modulating channel opening, closing, or conductance kinetics, often leading to altered cardiac repolarization and rhythm; KCNE4 modulates function via inhibition or augmentation of channel activity depending on the channel complex