FIG. 5.

Transient-transfection analysis of ChET promoter-luciferase reporters. (A) A transient-transfection experiment in NIH 3T3 cells was performed with a segment of ChET 8 cloned in either the forward or reverse orientation upstream of luciferase. The y axis of the graph represents the relative luciferase units, with the transfected material shown on the x axis. pGL2 represents the luciferase vector lacking a promoter. (B) A transient-transfection analysis was performed with the ChET 8 promoter-luciferase reporter transfected into NIH 3T3 cells in the presence of 2 μg of an E2F1 expression vector (cytomegalovirus [CMV] E2F1) or the pCDNA3 vector as a control. The cdc2 promoter-luciferase reporter construct was used as a control in both panels A and B. (C) Transient-transfection analysis of the ChET 9-luciferase reporter construct was performed in NIH 3T3 cells. A graphical representation of the results is shown with the dhfr promoter used as a positive control. (D) Overexpression of E2F1 upregulates ChET 9 promoter activity. Cotransfection experiments were performed containing 2 μg of a CMV E2F1 expression construct with the ChET 9-luciferase construct or the dhfr-luciferase reporter vector as a control. Results of the luciferase assay are shown in the graph as indicated for panel A.