Fig. 5. Expression of Fgf- and Wnt-inducible reporter genes. All images show gene expression patterns in wild-type embryos at tailbud stage. (A) Expression of erm. (B) Costaining of erm and fgf8 (darker staining). (C) Two-color staining showing expression of erm (red) and fgf8 (blue). (D) TOPdGFP expression. (E) Costaining of TOPdGFP and fgf8. (F,G) Parasagittal sections at the locations indicated in E showing TOPdGFP expression in a domain lateral and posterior to the hindbrain (F) and fgf8 expression in the hindbrain (G). Preotic domains are indicated by asterisks. Abbreviations: p, prechordal plate; hb, hindbrain. (A,B,E) Dorsal views with anterior upward. (C) Dorsolateral view with anterior upward. (D) Lateral view with anterior upward and dorsal to the right. (F and G) Dorsal is to the right and anterior is upward. Scale bars: A,B,E, 150µm; C, 40 µm; D, 175 µm; F,G, 25 µm.