Figure 8

NMDA receptor transport packets (NRTPs) and Nlg1 clusters were co-transported prior to synaptogenesis. (A) Time-lapse imaging of neurons cotransfected with CFP-Nlg1 (green) and NR1-DsRed (red) demonstrates movement of CFP-Nlg1 with NR1-DsRed (arrowheads) in both the anterograde and then retrograde direction. In the first panel, CFP-Nlg1 was seen at the tips of filopodia (arrows). Lower panels are enlargements of the boxed region in the upper panel. Time is in minutes and seconds. Scale bar, 10 μm. (B) Time-lapse images demonstrate that CFP-Nlg1 can move with (arrowheads) and without (arrows) NR1-DsRed. Grey arrows and arrowheads indicate original locations of clusters from first image. Scale bar, 10 μm. (C) CFP-Nlg1 clusters had higher mean velocities than NRTPs or co-transported NR1 and Nlg1. Error bars are standard error. Only mobile clusters were included in this analysis (*P < 0.02). (D) Comparison of the distribution of mean velocities of mobile clusters of Nlg alone (green) and colocalized CFP-Nlg1 and NR1-DsRed (yellow).