Fig. 2

gdf5^{uu3703/uu3703} mutants display loss of pectoral fin radials. All images depict pectoral fins with postcleithra removed in a dorsomedial view. Bone- and cartilage-stained pectoral fins of wild-type and gdf5^{uu3703/uu3703} zebrafish at 30 dpf (A-D), 35 dpf (E-G), and 60 dpf (H-J). Dashed boxes (A-D) mark magnified regions (A′-D′). (F,G) pectoral fins of two 35 dpf gdf5^{uu3703/uu3703} and gdf5^{uu3702/uu3702} zebrafish, respectively, and (I,J) pectoral fins of two 60 dpf gdf5^{uu3703/uu3703} zebrafish, displaying variable presence of bone at the position of proximal radial 2 or 3. (K) pectoral fin of a 90 dpf nonsibling wild-type zebrafish following μCT scanning and 3D segmentation. (L,M) pectoral fin of 90 dpf gdf5^{uu3703/uu3703} zebrafish following μCT scanning and 3D segmentation. The measurements in mm refer to SL. Asterisks highlight the absence of proximal radials 2-4. Arrowheads indicate the variably present bone in place of proximal radial 2 in gdf5^{uu3703/uu3703} fish. Arrows indicate increased porosity in the shoulder girdle of gdf5^{uu3703/uu3703} fish. In μCT images, the shoulder girdle (green) is rendered partially transparent to provide unobstructed views of the proximal radials (orange). Fin rays (white) were removed for clarity and shown instead in the insets. Distal radials are colored in pink. CSZ, cartilage segmentation zone; pr, proximal radial. Scale bars: 500 μm (A-M), 50 μm (A′-D′)