Fig. 6

Wnt8a mutations affect cell-non-autonomous activation of β-catenin and secretion.

(A–I) Clones of Wnt8a-Venus and Wnt8a-GFP mutants expressing cells transplanted into the animal pole of a WT embryo, fixed one hour after transplantation and stained with anti-GFP (green) and anti β-catenin (red) antibodies. Single confocal sections showing β-catenin is restricted to the membrane in the animal pole of WT embryos (A,A′). Wnt8a-GFP, Wnt8aCA-GFP and WntSA-GFP transplanted cells (B′–D′) induce a wide-range nuclear translocation of β-catenin in the host embryo (B–D) whereas Wnt8aCASA-GFP transplanted cells (E′) do not induce nuclear β-catenin translocation (E). Wnt8aCY-GFP transplanted cells (F′) induce nuclear translocation of β-catenin (F) only in the clone and in host cells directly adjacent to it (inset in F′). Secretion of mutant Wnt8a-GFP proteins is decreased compared to WT Wnt8a-GFP (G). β-catenin in shown in grey (A–F), GFP (green) and β-catenin (red) staining is shown merged (A′–F′). Scale bars: 50 µm.