Fig. S4

Spatial expression of zebrafish hmgb2a. (A–C) At early developmental stages hmgb2a is highly and ubiquitously expressed, but at tailbud stage hmgb2a transcripts are under-represented at the midline (C, white arrowhead). (D–G) During somitogenesis it is still broadly expressed with the exception of notochord and somites (F, grey arrow); the white asterisk in (G) marks the eye. (H and I) At 24 hpf, hmgb2a is highly and broadly expressed, with the notable exception of the somitic mesoderm and notochord. (L and M) At 2 dpf the hmgb2a signal is detectable in the rostral CNS, in pectoral fin buds, in lateral line neuromasts (L, arrowheads) and in the gut (L, arrow). All panels show whole-mount images. (A, C, E, G, I and M) Dorsal views; (B, D, F, H and L) lateral views, anterior to the left. All images are taken at 40× magnification. Pictures showing shortly stained embryos were chosen when expression details could not be clearly visualized upon prolonged staining (panels C, F–I). No significant signal was obtained in ISHs performed with a sense probe (data not shown).