FIGURE 6.

Deletion of the cytoplasmic tail of sortilin leads to delayed retrograde trafficking of BACE1. A, following transient transfection of BACE1 in HEK293 cells stably expressing vector, sort-V5, and sortΔC-V5, BACE1 at the cell surface was labeled by N-terminal BACE1 antibody on ice (green). The labeled BACE1 was allowed to internalize at 37 °C and subsequently chased for the indicated time periods. Following fixation and permeabilization, the cells were stained with anti-TGN46 antibody (red). Representative confocal images are shown. Magnification was ×100. B, quantitative analysis using ImageJ image analysis software was performed to measure the co-localization of BACE1 with the TGN, revealing the percentage of BACE1 successfully delivered to the TGN (n = 5).