FIGURE 8.

Characterization of mutant heterodimers of G87R ZnT2 and ZnT3 as well as G87R ZnT2 and ZnT4 using BiFC analysis. MCF-7 cells were transiently co-transfected with WT (A) and mutant (B) ZnT2 and examined for dimer formation. WT-ZnT2-YC (A) or G87R-ZnT2-YC (B) was co-transfected along with the vectors depicted on the left. YFP fluorescence (green fluorescence) indicates homo- or heterodimer formation. Hoechst 33342 (blue fluorescence) was used to stain nuclei, and Zinquin (small intracellular vesicles; blue fluorescence) was used for zinc staining. C, MCF-7 cells were transiently co-transfected with equal amounts of expression plasmids, as depicted above. Western blot analysis was performed after SDS-PAGE under denaturing conditions, using an anti-GRP-78 antibody to explore possible ER stress.