FIG. 8.

PR-DBD is required, but not sufficient, for JDP-2 enhancement of PR transactivation domains, while JDP-2 and SRC-1 synergize to coactivate AF-2 but not the N terminus. (A) Cos-1 cells were cotransfected with the Gal4DBD-PR chimeric constructs indicated, including BnGal4DBD (1 ng), AF-1-Gal4DBD (1 ng), or GalDBD-LBD (50 ng), together with the 5×-GalUAS-luc reporter (500 ng), in the presence or absence of various amounts of pCR3.1-JDP-2 (34 to 137 ng). Cells transfected with GalDBD-LBD were treated with vehicle or 10 nM R5020 24 h prior to harvest. Constructs lacking the LBD did not receive hormone. (B) Cos-1 cells were transfected with pfPR-DBD-VP16 (50 ng) together with PRE₂-TATA-luc (200 ng) in the presence or absence of pCR3.1-SRC-1 (50 to 200 ng) or pCR3.1-JDP-2 (34 to 137 ng). (C) Cos-1 cells were transfected with phPR-B (1.5 ng) (leftmost panel), DhLBD (50 ng) (middle panel), or BnDBD (1.5 ng) (rightmost panel), together with PRE₂-TATA-luc (200 ng), in the presence or absence of pCR3.1-SRC-1 (200 ng) or pCR3.1-JDP-2 (137 ng). Cells transfected with PR-B or DhLBD were treated with vehicle or 10 nM R5020 for 24 h. Relative luciferase activity and severalfold hormone induction values were calculated as for Fig. 5. Values are averages ± SEM of at least three independent experiments.