KCNIP4 is a member of the family of voltage-gated potassium (Kv) channel-interacting proteins (KCNIPs),which belong to the recoverin branch of the EF-hand superfamily. Members of the KCNIP family are small calcium binding proteins. They all have EF-hand-like domains,and differ from each other in the N-terminus. They are integral subunit components of native Kv4 channel complexes. They may regulate A-type currents,and hence neuronal excitability,in response to changes in intracellular calcium.