CACNB4

This gene encodes a member of the beta subunit family of voltage-dependent calcium channel complex proteins. Calcium channels mediate the influx of calcium ions into the cell upon membrane polarization and consist of a complex of alpha-1, alpha-2/delta, beta, and gamma subunits in a 1:1:1:1 ratio. Various versions of each of these subunits exist, either expressed from similar genes or the result of alternative splicing. The protein encoded by this locus plays an important role in calcium channel function by modulating G protein inhibition, increasing peak calcium current, controlling the alpha-1 subunit membrane targeting and shifting the voltage dependence of activation and inactivation. Certain mutations in this gene have been associated with idiopathic generalized epilepsy (IGE), juvenile myoclonic epilepsy (JME), and episodic ataxia, type 5. [provided by RefSeq, Aug 2016]

Full Name

Calcium Voltage-Gated Channel Auxiliary Subunit Beta 4

Function

The 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.

Biological Process

Chemical synaptic transmission Source: GO_Central
Membrane depolarization Source: Reactome
Neuromuscular junction development Source: GO_Central
Regulation of voltage-gated calcium channel activity Source: UniProtKB

Cellular Location

Cytosol; Cytoplasmic side of plasma membrane; Plasma membrane; Voltage-gated calcium channel complex; Synapse

Involvement in disease

Epilepsy, idiopathic generalized 9 (EIG9): A disorder 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.
Juvenile myoclonic epilepsy 6 (EJM6): 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.
Episodic ataxia 5 (EA5): A disorder characterized by episodes of vertigo and ataxia that last for several hours. Interictal examination show spontaneous downbeat and gaze-evoked nystagmus, mild dysarthria and truncal ataxia.