Association of L-type calcium channels with a vacuolar H⁺-ATPase G2 subunit

The class C L-type calcium (Ca²⁺) channels have been implicated in many important physiological processes. Here, we have identified a mouse vacuolar H⁺-ATPase (V-ATPase) G2 subunit protein that bound to the C-terminal domain of the pore-forming α(1C) subunit using a yeast two-hybrid screen. Protein-protein interaction between the V-ATPase G subunit and the α(1C) subunit was confirmed using in vitro GST pull-down assays and coimmunoprecipitation from intact cells. Moreover, treatment of cells expressing L-type Ca²⁺ channels with a specific inhibitor of the V-ATPase blocked proper targeting of the channels to the plasma membrane. (C) 2000 Academic Press.