Fig. 1. The expressions of fz8a and wnt8b are overlapped during late gastrulation of zebrafish embryos. (A-D) Dorsolateral views of embryos that were double stained for fz8a (red) and wnt8b (blue) mRNA. (A) At 90% epiboly stage, wnt8b started its expression in the posterior boundary of fz8a expression domain. (B) At 100% epiboly stage, the posterior boundary of fz8a expression domain, where wnt8b expression was overlapped, was gradually decreased; thus, the two adjacent expression domains for fz8a and wnt8b were separated. (C,D) Magnified images of insets from A and B, respectively. The broken red and blue lines indicate the posterior boundary of fz8a expression and anterior boundary of wnt8b expression, respectively. Arrows indicate fz8a-expressing cells remained in the wnt8b expression domain. Scale bars: in A, 100 µm for A,B; in D, 100 µm for C,D.