Figure 1.

Characterization of syncollin-dsRedE5TIMER behavior in MIN6 β-cells and primary mouse islets. A, λ excitation peak spectra obtained from a 10-nm step acquisition of primary mouse islet cells, 48 h post-transduction with syncollin-dsRedE5TIMER. Green and red colored bars represent emission detection ranges for young and old granule populations, respectively. Shown is confocal immunofluorescence imaging (B) and co-localization analysis (C) of young and old granule populations and anti-insulin–stained granules in mouse MIN6 cells at 24, 48, and 72 h post-transduction with syncollin-dsRedE5TIMER. Shown is representative Western blotting (D) and representative densitometry analysis (E) of syncollin, insulin granule–associated proteins, and β-actin expression after subcellular sucrose fractionation of MIN6 cells, 72 h post-transduction with syncollin-dsRedE5TIMER. F, Western blotting of syncollin and prohormone convertase PC2 in MIN6 cells, after 1-h 2.8 mm glucose basal and 1-h 2.8 or 16.7 mm glucose stimulation assay. Medium was precipitated with TFA protein precipitation. G, HTRF assay of secreted insulin from dispersed primary mouse islets normalized to DNA content after glucose-stimulated secretion assay, after a 48-h culture with or without transduction of syncollin-dsRedE5TIMER. H, confocal fluorescence imaging of primary mouse and human islet cells at 18, 24, 48, and 72 h post-transduction with syncollin-dsRedE5TIMER. ns, not significant.