Fig. 8. fgf24 is required for pectoral fin development. (A,B) Dorsal views of shh expression in 24 hpf wild-type (A) and fgf24-E3I3 morpholino-injected (B) embryos. shh is detected in the pectoral fin buds (arrows) and floor plate (arrowhead) of wild-type embryos (A), but only in the floor plate of fgf24-E3I3 morpholino-injected embryos (B). Skeletal preparations of one-month-old wild-type (C,D) and fgf24-E3I3 morpholino-injected fish (E,F) shown in lateral (C,E) and ventral (D,F) views. Bone is stained red and cartilage blue. In wild-type fish, exoskeletal (cleithrum and postcleithrum) and endoskeletal (scapula, distal radials and lepidotrichs) components of the pectoral fin are visible (C). By contrast, only exoskeletal components can be identified in fgf24-E3I3 injected fish (E). cl, cleithrum; dr, distal radials; lep, lepidotrichs; pcl, postcleithrum; sc, scapula. Scale bar: in A, 50 µm for A,B.