Figure 3

Suppression of BMP signaling after 8 hpf does not affect neural induction. In situ hybridization of heat-shock induced Tg (hsp70l:dnBmpr1aa-GFP) (A) and DMH1-treated (B) embryos analyzed at 10 hpf. The upper panels in (A,B) indicate anterior part of embryos with dorsal to the bottom, and the lower panels indicate the lateral view with anterior to the left. (A) Inhibition of BMP signaling by heatshock-induced DN-Bmpr1aa at 5.3 hpf for one hour disrupted the expression pattern and caused ectopic expression of sox2 and sox3 (arrowheads), whereas heat shock treatment after 8 hpf did not alter the expression pattern of sox2 and sox3. (B) DMH1 treatment at 5.3 for one hour phenocopies the effect of heat-shocked Tg (hsp70l:dnBmpr1aa-GFP), which is the alternating pattern and ectopic expression of sox2 and sox3. DMH1 treatment after 8 hpf had no effect on the expression pattern of sox2 and sox3. n, total number of embryos analyzed from three independent experiments. (C) sox2-expressing areas were measured using ImageJ. It should be noted that inhibiting BMP signaling using DN-Bmpr1aa or DMH1 slightly increased sox2-expressing areas; however, this was not statistically significant. n, total number of embryos analyzed from three independent experiments. The percentages in each panel in (A,B) indicate the proportion of embryos displaying the same phenotype as that shown in the photographs of the total embryos examined. Quantitative data are presented as mean ± standard deviation (SD). n.s., not significant.