Figure 2
From: Hedgehog signaling is required at multiple stages of zebrafish tooth development
Zebrafish mutant for shha do not exhibit tooth-related developmental gene expression and do not form mature teeth. (A, B) Ventral views of the pharyngeal region at 100 hpf stained with alizarin red to highlight calcified structures. Teeth appeared normal in wild-type and shhat4 heterozygous individuals (A), but were not detected in shhat4 homozygous mutant siblings (B). mRNA in situ hybridization analysis at 56 hpf demonstrated that pharyngeal tooth-related expression of dlx2b (C, D), fgf4 (E, F), lhx8a (G, H), and pitx2 (I, J) was completely absent from homozygous mutant embryos but present in sibling controls possessing at least one wild type shha allele. Expression of ptc1 in the tooth-forming region appeared to be maintained in all genotypes (K, L). (C-L) Dorsal views, anterior to the left, position of right side tooth germs indicated (arrows). Scale bars: (B) 50 μm, (D) 100 μm.