Fig. 5. Effects of ectopic expression of Slit1 in chick hindbrains. All panels show flat-mount chick hindbrains electroporated at stage 10-11, fixed at stage 17-19 and immunostained using anti-SC1 antibodies to show motor axon pathways (green). (A) A control GFP construct has been electroporated (red); (B-F) a hSlit1-myc construct has been electroporated (red). Rhombomere levels are numbered on the non-electroporated (right-hand) side. Exit points are shown by an asterisk in some cases. White arrowheads show regions in which axons exit at the incorrect exit point (B,C), stall (D) or overshoot the exit point and form tangles (E,F). Scale bar: 150 µm.