PAPC–Fz7 and C-cadherin–Fz7 interactions reduce cadherin–catenin complexes at cell membranes. DMZ explants were injected with the indicated constructs, fixed, and fluorescently immunostained using either specific xC-cadherin (6B6) or xβ-catenin antibody (PGDS 7D12). (A, top) Fluorescent immunostainings for endogenous xC-cadherin. Endogenous xC-cadherin membrane staining was reduced upon xPAPC-GFP expression and upon formation of the xPAPC–xFz7–TM1 complex (BiFC). (bottom) Quantitative evaluation of endogenous xC-cadherin staining. The mean grayscale value (intensity) of xC-cadherin staining was measured and plotted into box and whisker diagrams (box plots). For more details, see Materials and methods. (B and C) Fluorescent immunostainings for endogenous xβ-catenin. Endogenous xβ-catenin membrane staining was reduced upon xPAPC-GFP expression and upon formation of the xPAPC–xFz7–TM1 and xC-cadherin–xFz7 complexes. xPAPC-induced reduction of xβ-catenin could be restored by Wnt-11 depletion. The graphs show quantitative evaluation of endogenous xβ-catenin staining. The mean grayscale value (intensity) of xβ-catenin staining was measured and plotted into box and whisker diagrams (box plots). Injection amount was as follows: 1 ng xPAPC-GFP RNA, 1 ng xPAPC-YN RNA, 1 ng xC-cadherin–YC RNA, 500 pg xFz7-YN RNA, 500 pg xFz7-TM1-YC, 20 pg xWnt-11 RNA, and 1 pmol xWnt-11 MO. Bars, 20 µm. In the box plots, each box represents the values between the 25th (dark gray) and 75th quartiles (light gray). The line within the boxes indicates the median values, and the blue rhombi show the mean values. Error bars indicate SEM. Student’s t test was performed (*, p < 0.05 to wild type; **, p < 0.05 to xPAPC). # exp., number of experiments.