GDP-Fuc or mSlc35c1 overexpression inhibits maternal Wnt signaling. (A-D) in situ hybridization of a direct Wnt signal target gene bozozok(dharma) in sphere stage (4hpf) embryos; lateral views. (E) Quantification of bozozok domain angle (e.g. dashed lines in A-D) in each group. The sample sizes for each treatment were as follows: gmds MO (N=35), wt (N=18), GDP-Fuc(N=54) and mSlc35c1(N=26). Ordinary One-way ANOVA between sample group means, p<0.0001. (F) qPCR of bozozok, a direct Wnt target gene in WT, GDP-Fuc injected or mSlc35c1 expressing embryos. bozozok expression is normalized to expression of the eef1a1a house keeping gene. (G) Schematic illustration of an embryo demonstrates the boxed regions shown in (H-K) for β-catenin protein localization at 512 cell stage (3hpf). View of the dorsal margin, as indicated by the nuclei of the yolk syncitial layer, which lack membranes (red arrowhead) at the margin, and the strong nuclear label (white arrowhead) in cells within the “core” region (i.e. closest to the Wnt8a source). The nuclear localization of β-catenin in the core region of (H) WT (n=6) and (I) mSlc35c2 (n=5) injected embryo, but is faint in either (J) GDP-Fuc (n=7) or (K) mSlc35c1 (n=9) injected embryos. Note: ** Tukeyós procedure after ANOVA **p<0.01; * p<0.05. Bar=100 μm.