Figure 4

oGRN gene expression in primary cranial dermal denticles. (A) In situ hybridization (ISH) for oGRN genes in primarily cranial dermal denticles of Ancistrus sp. at 96 hpf. Whole-mount (left) and section (right) in situ hybridization of represented oGRN genes at the eruption stage. Pitx2 and shha transcripts were detected in the epithelium. Dlx2a, b-catenin, wnt10a, bmp4, pax9, and fgf3 transcripts were in both the epithelium and mesenchyme. Black dotted lines indicate the borderline of the epithelium and dentin cone. Green dotted lines indicate the borderline of the epithelial or dentin cone and mesenchyme. For the epithelium genes, the left and right section panels show the entire epithelial and distal tip expression, respectively. In dlx2a, bmp4, and b-catenin staining, the section panels show both epithelial and mesenchymal expression (left) and epithelial distal tip expression (right). In wnt10a, pax9, and fgf3 staining, the section panels show the epithelial tip expression (left) and local mesenchymal expression adjacent to the dentin (right). Note that, to display the representative oGRN gene expression patterns, we selected different slice positions of dermal denticles for some of the section ISH photos. Accordingly, some denticle germ morphology appear to be different from others. Scale bars: 100 µm (left) and 50 µm (right). e; epithelium, m; mesenchyme. (B) Schematic illustration of oGRN gene expression patterns in secondary cranial dermal denticles at the eruption stage. At least three biological replicates were investigated in each experiment.