Fig. S3
OPC distribution is grossly altered in the hindbrain of ptch1;ptch2 mutant embryos. In situ hybridisation for olig2 was performed on ptch1;ptch2 double mutant and sibling embryos fixed at 72 hpf. Dorsal (A, C) and transverse (B, D) views of sibling (A, B) and double mutant (C, D) embryos are shown. In transverse section, no olig2-expressing cells are seen dorsal to the central patch of cells around the midline in wild type embryos (B). In ptch1;ptch2 double mutants the distribution of these cells is greatly altered and cells are seen throughout the dorsal part of the hindbrain (D). |