Stargazin belongs to a group called voltage gated calcium channels (VGCCs) which are present in most excitable cells. Stargazin is thought to stabilize the calcium channel in an inactivated (closed) state. 
There are five high voltage activated calcium channel types (L, N, P, Q, and R) and one low voltage activated channel type (T). Each of these channels exists as a heteromultimer of a1, b, a2/ d and g subunits with the voltage activated calcium channel function carried by the a subunits. VGCCs exert spatial and temporal control over cellular calcium concentrations and serve to modulate neurotransmitter release, hormone secretion, muscle contraction, electrical activity, cell metabolism and proliferation, gene expression, and neuronal survival.