Fig. 3.

BDNF signalling is required for efficient polarised neuroblast migration.

Time-lapse movies made from the descending arm of the RMS in slices with GFP-labelled neuroblasts incubated with TrkB-Fc (blocking BDNF signalling) or TrkA-Fc as a control (all at 1 μg/ml) were analysed using Volocity. Representative migratory tracks of 15 cells over a 3 hour filming period from a control (A), a TrkB-Fc (B) or a TrkA-Fc-treated brain slice (C). White stars mark the end point of each migration track. OB shows the location of the olfactory bulb in each brain slice. Blocking BDNF signalling increased the percentage of time spent immobile by neuroblasts (D), significantly decreased the percentage of cells migrating towards the OB (E) and the overall cell displacement (F). Incubation with TrkA-Fc did not have any significant effect on all the measured parameters (D–F). Graphs show mean ± s.e.m. (n = 6–8 brain slices for each condition, ~ 15–30 cells analysed per slice); *p < 0.05, **p < 0.01, ***p < 0.001.