Fig. S10

BMS-833923 treatment recapitulates specific developmental defects observed in smoothened-null embryos. (A-P) 54 hpf ptch2:Kaede embryos treated with DMSO (A-D), 0.5 μM BMS-833923 (E-H), 2.5 μM BMS-833923 (I-L), or 5 μM cyclopamine (M-P) beginning at 1.5 hpf. (A, E, I, M) Lateral view showing overall embryo morphology and Kaede expression. BMS-833923 treated embryos display a dose dependent decrease in Kaede expression, as seen in adult regeneration experiments. White arrows indicate the heart. Cardiac edema is observed in 2.5 μM BMS-833923 (I) and, to a greater extent, 5 μM cyclopamine (M) treated embryos. (B, F, J, N) Ventral view showing reduced head size and partial cyclopia in 2.5 μM BMS-833923 (J) and 5 μM cyclopamine (N) treated embryos. Red bar indicates the distance between the eyes. (C, G, K, O) Higher magnification lateral view focused on the somites. Yellow arrows point to developing somites. U-shaped somites and incomplete muscle differentiation are seen in the 2.5 μM BMS-833923 treated embryo (K). Somites are more substantially disorganized in the cyclopamine-treated embryo (O). (D, H, L, P) Higher magnification lateral view focused on the notochord. BMS-833923 treated embryos have a reduced and disorganized notochord and floor plate. The floor plate and notochord of cyclopamine-exposed embryos is more severely affected, becoming nearly indistinguishable from surrounding tissue. Blue arrows point to the lateral floor plate. (Q, R) Confocal images of 31 hpf control and 0.5 μM BMS-833923-exposed (2 – 31 hpf) ptch2:Kaede embryos antibody stained for Engrailed (green, muscle pioneer cells), myosin heavy chain (MHC, red, muscle), and Kaede (blue). Hoechst-stained nuclei are grey. Scale bars for (A, E, I, M): 500 μm. All other scale bars: 100 μm.