Fig. S2
Bmp ligands are expressed in the developing pharyngeal arches prior to fgfr4. (A-H) Expression of the Bmp ligands, bmp2b (A-D) and bmp4 (E-H), and the Fgf receptor, fgfr4 (I-L), at 12, 14, 16 & 18 hpf. bmp2b is expressed in anteriorly developing pharyngeal tissues at 12, 14 and 16 hpf (A-C, arrows). Its expression is expanded at 18 hpf (D, arrows). Expression of bmp4 is broadly expressed at 16 hpf (G, arrows) which becomes more restricted by 18 hpf (H, arrow). Pharyngeal tissues expression fgfr4 only at 18 hpf (L, arrow), after expression of the Bmp ligands is observed. Lateral views, anterior to the left. Scale bar = 50 µm.