Fig. S4
Hedgehog signalling is not required for cxcr4b expression in epiphysial projection neurons.
Whole-mount in situ hybridization against cxcr4b at 28 hpf showing heads (A,B; lateral view) or the epithalamus (A’,B’; dorsal view with anterior up) of wild type (A,A’) or smob641 embryos (B,B’). At 28 hpf, cxcr4b is expressed on both side of the epithalamic midline (*) in epiphysial projection neurons in both wild type siblings (n = 9/9) and smob641 mutant embryos (n = 8/8). At this stage, cxcr4b is either only expressed in few left habenular neurons or not expressed yet in the habenulae. This expression could be detected in some wild type siblings (A’, black brackets, n = 3/9) but never in the habenulae of smob641 mutant embryos (B’, n = 8/8).