FIGURE 7.

Piasy represses the synergistic activation of PITX2 with other co-factors. A, CHO cells were co-transfected with PITX2A, Lef-1 FL, β-catenin, and Piasy or combinations of factors with the LEF-1 luciferase promoter. Transfections were performed as described in the legend to Fig. 4. Piasy repressed PITX2 transcriptional activity in the presence of PITX2 co-factors. The activities are shown as mean fold-activation compared with the LEF-1 promoter plasmid without PITX2A, Lef-1, β-catenin, or Piasy expression and normalized to β-galactosidase activity (± S.E. from 5 independent experiments). B, Pias1 was transfected with co-factors as in panel A without Piasy. Pias1 did not enhance or repress PITX2 transcriptional activity in the presence of PITX2 co-factors.