FIG. 6.

Effect of mutations of the c-fos SIE on TFII-I transactivation. NIH 3T3 cells were transfected with the indicated c-fos/Luc reporter constructs with or without TFII-I. Cells were serum starved for 36 h in 0.5% CS and then were stimulated for 2.5 h with 10% CS in DMEM. Cell extracts were then processed for luciferase activity. Data shown in panel A are from a representative experiment, and similar results were obtained from three qualitatively similar and independent experiments. All transfections were performed in duplicate for each experiment, and the values between the duplicates were within 10% of the mean. Data shown in panel B are the comparison of the relative enhancement of each mutant reporter gene by TFII-I cotransfection to the fold enhancement of the wild-type (WT) c-fos reporter activation by TFII-I.