Fig. 6 Misexpression of competence factors induces ectopic expression of preplacodal markers.
(A–C) Analysis of indicated gene expression patterns in control embryos and embryos carrying hs:gata3, hs:foxi1 and/or hs:tfap2a heat-shocked at 30% epiboly (4.5 hpf). Dorsal views with anterior up except bottom row in A, inset in B, which are lateral views with dorsal to the right. Note the ectopic expression of PPE markers, six4.1 (A), eya1 (B) and dlx3b (C) in neuroectoderm of embryos misexpressing one or more competence factors. (D–H) Dorsolateral views (anterior up) of mosaic embryos showing ectopic expression of dlx3b and six4.1 at 10.5 hpf. Donor cells obtained from Tg(hs:foxi1) injected with hs:gata3 and hs:tfap2a plasmid were transplanted into wild type hosts and heat shocked at 4.5 hpf at 39°C. Transplanted cells were identified with Strepavidin-FITC (arrows F, H). Mosaic embryos shows cell autonomous expression of dlx3b and six4.1 in the neural plate (compare E, F and G, H).