Fig. 8. Oligomerization of Xfz7 is sufficient to activate the Wnt/ß-catenin pathway in Xenopus embryos. (A) Embryos were injected with mRNA encoding Xfz7-BD-myc, Xfz7-myc and Xfz3C-myc. Protein extracts from injected embryos were separated by SDS-PAGE and immunoblotted with the anti-myc antibody. Xfz7-BD-myc dimer and oligomer are detected (arrowhead). (B) RT-PCR analysis of the Wnt/ß-catenin target gene siamois in animal caps after overexpression of different frizzled constructs as indicated. RT–: control without reverse transcriptase. ODC is a loading control. Analysis was performed at the early gastrula stage. (C) Localization of Xfz7-BD at the plasma membrane. Immunocytochemistry with the anti-myc antibody, performed on blastula animal caps isolated from Xfz7-myc or Xfz7-BD-myc injected embryos. The subcellular localization was analysed by confocal microscopy.