Ancillary protein that assembles as a beta subunit with a voltage-gated potassium channel complex of pore-forming alpha subunits. Modulates the gating kinetics and enhances stability of the channel complex. Assembled with KCNB1 modulates the gating characteristics of the delayed rectifier voltage-dependent potassium channel KCNB1 . Associated with KCNC4/Kv3.4 is proposed to form the subthreshold voltage-gated potassium channel in skeletal muscle and to establish the resting membrane potential (RMP) in muscle cells. Associated with KCNQ1/KCLQT1 may form the intestinal cAMP-stimulated potassium channel involved in chloride secretion that produces a current with nearly instantaneous activation with a linear current-voltage relationship.
Subcellular locations: Cell membrane, Cytoplasm, Perikaryon, Cell projection, Dendrite, Membrane raft
Colocalizes with KCNB1 at high-density somatodendritic clusters on the surface of hippocampal neurons.
Expressed in hippocampal neurons (at protein level) . Widely expressed with highest levels in kidney and moderate levels in small intestine.