Fig. 7. Activity of sox9a is necessary for the expression of col2a1 in most developing cartilage of the neurocranial, pharyngeal and pectoral skeleton. (A-F) Expression of sox9a. (G-L) Expression of col2a1. (A,B,G,H) Wild-type animals. (C,D,I,J) Homozygous mutant jef^tw37 embryos. (E,F,K,L) Homozygous mutant jef^hi1134 embryos. Photographs are a montage with focus on the pharyngeal cartilages, and the pectoral girdle. All animals are 68 hpf. 1 and 2, first and second pharyngeal arches; co, scapulocoracoid; ed, endoskeletal disc; ov, otic vesicle. (A,C,E,G,I,K) Lateral views, anterior towards the left. (B,D,F,H,J,L) Ventral views, anterior towards the left. Scale bars: in K, 100 µm for A,C,E,G,I,K; in L, 100 µm for B,D,F,H,J,L.