FIG. 5.

LEF/TCF-dependent transcriptional activity in BPD cells transiently expressing β-catenin, plakoglobin, and their stabilized mutants. BPD cells were transiently cotransfected with pTOPflash and pCMV-renilla luciferase reporter plasmids and, where indicated, with expression vectors for β-catenin (β), plakoglobin (Pg), stabilized mutant β-catenin (mβ), or stabilized mutant plakoglobin (mPg). As a control, an expression vector for GFP was used. (A) Expression of β-catenin, plakoglobin and their stabilized mutants in BPD cells. Western blots of total cell lysate were probed with anti-β-catenin (anti-β) or antiplakoglobin (anti-Pg) antibodies. Eukaryotic elongation factor 2 levels were used as an internal control (anti-EF; lower panel). (B) Subcellular localization of β-catenin, plakoglobin, and their stabilized mutants in BPD cells. Cells were stained with anti-β-catenin (anti-β) or antiplakoglobin (anti-Pg) MAb. Nuclei were visualized with DAPI. Occasionally, nuclear localization of β-catenin and plakoglobin was observed in cells expressing high levels of these proteins. Bar, 20 μm. (C) Effect of β-catenin, plakoglobin, and their stabilized mutants on TOPflash (closed bars) or FOPflash (open bars) luciferase reporter activity. The value for BPD cells transfected with β-catenin was set at 100. Error bars indicate standard deviations.