Fig. 4. foxi1 pharyngeal arch expression. (A-C) foxi1 expression in whole-mount embryos. (A) 18 hpf, lateral view; (B) 18 hpf, dorsal view; (C) 28 hpf, dorsal view. (D,E) foxi1 expression in 5 µm sections through the pharyngeal arches of 28 hpf embryos. (D) Transverse section and (E) sagittal section. (F,G) 15 µm sections through pharyngeal arch region of 26 hpf embryos: foxi1 expression shown in purple, dlx2a expression shown in red. Transverse (F) and sagittal (G) sections. a, anterior; 1, lateral; m, medial; p, posterior.