Enables voltage-gated ion channel activity involved in regulation of postsynaptic membrane potential and voltage-gated ion channel activity involved in regulation of presynaptic membrane potential. Involved in forebrain development; negative regulation of neuronal action potential; and negative regulation of sensory perception of pain. Located in several cellular components, including Golgi apparatus; dendrite; and neuronal cell body. Is active in calyx of Held; glutamatergic synapse; and glycinergic synapse. Is integral component of postsynaptic membrane and integral component of presynaptic membrane. Colocalizes with synaptic vesicle. Biomarker of sciatic neuropathy and status epilepticus. Orthologous to human KCNC4 (potassium voltage-gated channel subfamily C member 4). [provided by Alliance of Genome Resources, Apr 2022]