FIG. 3.

Pin1 enhances Tcf4 and suppresses AR coactivation by β-catenin. (A) CV1 cells were transfected with pTopflash (20 ng), Pin1 and β-catenin expression vectors were used as indicated (−, not used), and pRL-CMV (2.5 ng) was used as an internal control. (B) CV1 cells were transfected with ARE₄-luciferase (10 ng), AR, Pin1, and β-catenin expression vectors as indicated, and pRL-CMV (2.5 ng) was used as an internal control. (C and D) 293T cells were transfected with AR (10 ng), ARE₄-luciferase (10 ng), pRL-CMV (1 ng), empty pcDNA, and pBluescript as indicated. In panel D, the added empty pcDNA3 is calculated to yield equimolar amounts of pcDNA3 vector in all samples. (E and F) CV1 cells were transfected with PSA-luciferase (10 ng) (E) or ERE₂-luciferase (10 ng) (F) reporters, together with AR, ERα, Pin1, and β-catenin expression vectors as indicated and pRL-CMV (2.5 ng) as an internal control. DHT or estradiol (E2) was added at a final concentration of 10 nM as indicated. Luciferase activities were determined 24 h after hormone treatment. Results are given in relative light units (RLU).