Figure 3

Preferential axonal targeting of BACE1-YFP over time after transfection in cultured hippocampal neurons. (A) Cultured hippocampal neurons were co-transfected with plasmids expressing BACE1-YFP and Cerulean on DIV5 (when they have already developed dendrites and long axons) and polarized distribution of BACE1-YFP was analyzed after 1, 3, and 5 days of transgene expression. Representative images of BACE1-YFP distribution neurons 1 or 5 days after transfection are shown. MAP2 staining was used to identify dendrites and, by exclusion, axons (arrowheads). (B) Mean axon-to-dendrite fluorescence intensity ratios were calculated for BACE1-YFP and Cerulean along major axon and dendrite segments in co-transfected neurons analyzed after 1, 3, and 5 days of transgene expression (n = 23-28 neurons each imaged from four coverslips per time point, two independent cultures).