Figure 6.

DACH1 inhibits serum-induced activation of AP-1 activity. (A) HEK293T cells were transfected with luciferase reporter plasmids encoding either a multimeric AP-1 site (A), the c-jun promoter (B), the junB promoter (C), or the c-fos promoter (D) and DACH1 mammalian expression vectors. A β-galactosidase report gene driven by a β-actin promoter was used to normalize the transfection deficiency. Data are shown as -fold change in luciferase activity. Data are mean ± SEM of n = 6 separate transfections. (E–G) 3T3 cells were transfected with a reporter plasmid encoding either the c-jun promoter (E) or c-fos promoter (F) and a DACH1 mammalian expression vector. Cells were serum starved and stimulated with 15% FBS for 6 h before the luciferase activity was determined. 3T3 cells were transfected with the luciferase reporter plasmid for the c-jun or c-fos promoter and a mammalian expression vector encoding Ski (G). Cells were treated as shown in E and F. The expression vector encoding Ski does not significantly reduce reporter activity. Data are mean ± SEM of n = 6 separate transfections.