FunctionThe beta subunit of voltage-dependent calcium channels contributes to the function of the calcium channel by increasing peak calcium current, shifting the voltage dependencies of activation and inactivation, modulating G protein inhibition and controlling the alpha-1 subunit membrane targeting.
Tissue specificityExpressed predominantly in the cerebellum and kidney.
Involvement in diseaseGenetic variations in CACNB4 are the cause of susceptibility to idiopathic generalized epilepsy type 9 (IGE9) [MIM:607682]. IGE9 is characterized by recurring generalized seizures in the absence of detectable brain lesions and/or metabolic abnormalities. Generalized seizures arise diffusely and simultaneously from both hemispheres of the brain. Genetic variations in CACNB4 are the cause of susceptibility to juvenile myoclonic epilepsy type 6 (EJM6) [MIM:607682]. EJM6 is a subtype of idiopathic generalized epilepsy. Patients have afebrile seizures only, with onset in adolescence (rather than in childhood) and myoclonic jerks which usually occur after awakening and are triggered by sleep deprivation and fatigue.
Sequence similaritiesBelongs to the calcium channel beta subunit family. Contains 1 SH3 domain.