A functional Ena–VASP binding site in CC2 is required to mediate axon repulsion downstream of Robo activation. (A) Heatmaps showing the distribution of growth cone filopodia relative to an HGF gradient over time. HGF gradient was started at time 0; filopodia within 0–45° are nearest the pipette. Color scale indicates the number of filopodia. n = 18 growth cones per condition. (B) Lengths of all filopodia scored before (−) and after (+) onset of HGF gradient. Black lines, mean ± SD; n = 13,727 filopodia. (C) Length of filopodia nearest (proximal, top) and furthest (distal, bottom) from the HGF gradient over time. Mean ± SEM. Black bars denote points where MR was significantly different from GFP and CC2m (P < 0.001). (D) Box and whisker plots of axon turning angles in response to the indicated gradients. n = 18 growth cones per condition. n.s., P > 0.05; ****, P < 0.0001; one-way ANOVA.