Figure 4

Transcription activity of the serially deleted promoter regions. The pGL3-basic vector constructs containing fragments of various lengths were transfected or co-transfected with the pCMV-Sp1 or pSG5-Ap1 expression vectors into CHO cells. For the co-transfection experiments, the luciferase reporter constructs and factor expression vectors were used at 1:4 concentration ratio. The relative luciferase activity (mean ± SEM for triplicate wells) is presented as the percentage of the activity resulting from the promoter transfection alone in each group.