Nonchannel functions of the calcium channel gamma subunit: insight from research on the stargazer mutant.

Voltage-dependent calcium channels (VDCC) are essential regulators of intracellular calcium concentration, which in turn influences a broad spectrum of cellular functions especially in neurons. Identification of several calcium channel mutations as the cause of neurological disorders in human and mouse indicates the importance of the integrity of these channels to neuronal function. Studies of mutant mice, each carrying a disrupted gene of a different VDCC subunit, have revealed many unexpected roles of these molecules and have significantly advanced our knowledge of subunit function in the last few years. This review addresses recent discoveries of the function of the gamma2 subunit, also named stargazin, with special emphasis on roles other than calcium conductance.