Fig. 4. ZnT-8 overexpression is INS-1E cells. (A) Western blot with anti-human ZnT-8 antibody showing the presence of the fusion protein at the expected size (i.e. 67 kDa) in ZnT-8-expressing cells but not in control EGFP-expressing cells. (B) Confocal fluorescence microscopy of ZnT-8-EGFP-expressing INS-1E cells. A representative cell displaying punctuated staining consistent with insulin colocalization. The panel on the right is a magnified image of the selected area of the cell on the left, showing that ZnT-8-EGFP is mainly localized in granules in close proximity to the plasma membrane. (C) Fluorescence microscopy of ZnT-8-expressing cells. Arrows indicate localization of ZnT-8-EGFP at the plasma membrane. Bars, 10 µm (C, left panel in B); 5 µm (B, right panel).