Fig. S2

Fig. S2 Lateral positioning of longitudinal otpb:gfp-positive axons is altered in arnt2^hi2639c mutants. Dorsal views of confocal z projections of the hindbrain of otpb:gfp transgenic embryos co-labeled with anti-GFP and anti-3A10 (A-D) at 72 hpf are shown. (A,B) Wild-type siblings display normal medio-lateral positioning of otpb:gfp positive axons (arrows in A). (C,D) In arnt2^{hi2639c/hi2639c} homozygous mutants, longitudinal projections of otpb:gfp axons are shifted towards the midline (arrows in C). Midline crossing of Mauthner axons is not affected in arnt2^hi2639c mutants, suggesting grossly normal hindbrain development (compare arrowheads in B,D). (E) Quantification of mediolateral positioning of otpb:gfppositive longitudinal axons at the anterior-posterior level of Mauthner neurons (see III in B), of the distance of MA neurons (see II in B) and of otpb:gfp hindbrain neurons (see I in B) in arnt2^{hi2639c/hi2639c} homozygous mutants or wild-type siblings. Numbers in parentheses indicate the number of embryos analyzed. ***P<0.0001; n.s., not significant. Scale bar: 50 μm.