FIGURE 8.

Cross-linking studies using bifunctional MTS reagents at hSERT Cys double mutants. HEK-293 cells transiently expressing the hSERT C109A, Cys single mutants, or Cys double mutants were incubated with 100 μm MTS-3-MTS (A and B) or 100 μm MTS-4-MTS (C and D) for 10 min at room temperature. Following incubation, the cells were washed twice and assayed for [³H]5-HT uptake as described under “Experimental Procedures.” The data were normalized to the total uptake of each individual mutant. Data represent the mean ± S.E. (error bars) from three independent experiments performed in triplicate. #, p < 0.001 versus C109A and each single mutant forming the double mutant using a one-way analysis of variance with Bonferroni's post hoc test.