FIGURE 10.
Effect of Zn2+ on glycine transport by wild-type GlyT2 and the Y705C mutant. Transiently transfected COS7 cells expressing wild-type GlyT2, the Y705C mutant, or the indicated combinations of the respective cDNAs were assayed for [3H]glycine transport for 5 min in HBS containing 75 mm NaCl at the indicated pH and 10 μm final glycine concentration (A and B) or increasing glycine concentrations (C) in the presence of the indicated ZnCl concentrations (A–C). NaCl was isotonically substituted by choline chloride. B, dose-response data were fit to logistic curves. C, transport data were fitted to hyperbolae, and kinetic parameters were obtained from the best fit. Mean change significantly different from wild-type GlyT2. *, p < 0.05 in Student's t test.