FIGURE 6.
Overexpressing CaM wt and CaM1,2,3,4 did not alter the pattern of CaVβ stimulation of CaV1.2 plasma membrane targeting. A, HA-tagged CaV1.2 wt was expressed transiently either in the HEKT cells or in the stable CaVβ3 cell line. Cell surface expression of the CaV1.2 protein was quantified as described for supplemental Fig. S2. The number of fluorescent cells was not significantly influenced by overexpressing the wild type CaM or the dominant negative mutant CaM1,2,3,4. The numerical values can be found in Table 1 and supplemental Table SIV. B, HA-tagged CaV1.2 wt and the double W470A/I471A mutant were expressed transiently either in the stable CaVβ3 or in the stable CaVα2bδ cell line. Cell surface expression of the CaV1.2 protein was quantified as described for supplemental Fig. S2. The number of fluorescent cells was not significantly increased by overexpressing CaM wt in any cell line as compared with the control CaV1.2 cells (p > 0.05). Similar data were obtained with the W470A mutant that abrogated CaVβ3 binding and stimulation of CaV1.2 plasma membrane targeting. The numerical values can be found in Table 1 and supplemental Table SIV.