Fig. 1
Regional loss of eda expression is associated with reduction of dentition in the zebrafish lineage. (A) Teeth were lost from the mouth and upper pharynx in the zebrafish (D. rerio) lineage after its divergence from that of the Mexican tetra (A. mexicanus). (B) eda expression in upper (arrowhead) and lower (arrow) jaws of Astyanax. (C and D) eda expression in upper (arrowhead) and lower (arrow) pharynx of Astyanax. (E) Absence of eda expression in the mouth of Danio. (F and G) eda expression in the lower (arrow) but not upper pharynx of Danio. All eda expression shown is in mesenchyme, as confirmed by sectioning (Fig. S1). Abbreviations: e, eye; hpf, hours postfertilization; lpt, lower pharyngeal teeth; m, mouth; ot, oral teeth; upt, upper pharyngeal teeth; y, yolk. (Scale bars, 50 μm.)