Fig. 1

The ventrolateral domain of Wnt/β-catenin signaling is dependent on both β-catenin-1 and β-catenin-2, whereas organizer β-catenin-mediated gene activation is dependent only on β-catenin-2. (A–H) TOP-GFP embryos were injected with βcat1MO (MO1) (B and F), MO2 (C and G), or both βcat1MO and βcat2MO (MO2) (D and H) and compared to uninjected embryos (A and B) after in situ hybridization with probe for GFP at 50% epiboly (A–D) or 70% epiboly (E–H). Embryos are shown in animal view (A–D) or lateral view (E–H). (I and J) chd expression is excluded from the ventrolateral Wnt/β-catenin signaling domain. TOP-GFP embryos at 70% epiboly were assayed by two color in situ hybridization for both GFP (blue) and chd (red) expression. A single embryo is presented in both animal pole (I) and vegetal pole (J) views to show the complementarity of chd and Wnt signaling domains at this stage. The arrows in (I and J) point to a slight region of overlap of the chordin expression and Wnt signaling domains. All embryos are shown with dorsal to the right; (E–H) animal pole is to the top.