FIG. 4.
DP103721-825 represses the transcription of SF-1 target promoters. (A) The concentration-dependent influence of GAL4-fused full-length or truncated DP103 on the transcriptional activity of SF-1. JEG3 cells were cotransfected with 0.05 μg of CMV-SF-1 and either GAL4-DP1031-825, GAL4-DP103721-825, or GAL4-DP1031-727 (0, 0.1, 0.3, 1.0, and 3.0 μg), along with 0.5 μg of the SF-1 luciferase reporter plasmid S25. (B) The repression effect of DP103 is observed only in the presence of SF-1. Transfection was performed as described above, with 3 μg of GAL4-DP103721-825 or GAL4-DP1031-727. The empty expression vector CMV-neo or GAL4 was used as control for SF-1 and DP103, respectively. (C) Concentration-dependent influence of GAL4-fused full-length or truncated DP103 on the transcriptional activity of an SF-1-responsive rat P450scc reporter. Transfection was performed as described above, with 0.5 μg of the SF-1 luciferase reporter plasmid P450scc. (D) SF-1 is required for the repression effect of DP103. The repression was abrogated when the two SF-1 binding elements in the P450scc promoter were mutated. Transfection was performed as described above. Results (means ± SD) are expressed as cRLU normalized to β-galactosidase activity and represent three independent experiments, each performed in duplicate.