FIGURE 3.
Expression and vesicle targeting in chromaffin cells. A, confocal images of untransfected DKO cells and DKO cells transfected with NPY-DsRed (red) and either WT syb2, or lipid-anchored syb2, or ΔTMD-94 (green). The inset and line scan panels correspond to the white squares and dashed lines in the merged panels. In line scan panels, black traces indicate syb2 variants, and red indicates NPY-DsRed. B, Pearson's coefficient quantifies colocalization. Except for ΔTMD-CAC, lipid-anchored syb2 showed targeting comparable with WT syb2. WT and all lipid-anchored syb2 constructs targeted more efficiently than ΔTMD-94. p value for ΔTMD-LC is shown. The negative control construct ΔTMD-94 was well below all the other constructs (p value range 10−8–10−4). C, quantification of total fluorescence intensity indicates roughly similar expression levels for all constructs. n = 18–33 cells from three DKO embryos. **, p < 0.01; ***, p < 0.001. Scale bars, 3 μm.