Voltage-gated potassium (Kv) channels are key components of the potassium currents in the heart and central nervous system. In the heart, Kv4 channels are involved in the repolarization phase of the action potential. In the brain however, these channels prevent reverse-propagation of action potentials. Found associated with Kv4 channels are a group of calcium-binding proteins termed KChIPs (Kv channel interacting proteins). KChIPs are small molecular weight proteins that bind to the cytoplasmic amino termini of Kv4 alpha-subunits and help to modulate its function.
There are currently three known KChIPs; KChIP1 expressed in the brain; KChIP2 expressed in the brain, heart, and lung, and has three isoforms, a, b, and c; and KChIP3, also known as calsenilin and DREAM (downstream regulatory elements (DRE)-antagonist modulator) which is expressed in the brain and testis.