FIG. 6.

Regulatory effects of p53 protein on WRN promoter activity in Saos2 cells. (A) pGL3/A, a WRN-Luc plasmid containing the full-length WRN promoter region, was cotransfected with increasing amounts of pC53-SN3 (closed circles) or pC53-249 (open circles) into Saos2 cells, which are known to be deficient in active Rb and p53. The activity of the WRN promoter in the transfected cells was determined and compared with the activity of pGL3/A alone. The values represent relative activities of pGL3/A expressed in the presence of p53, assuming the luciferase activity with pGL3/A alone to be 1.0. The data were reproducible in two independent experiments. (B) WRN-Luc plasmids (pGL3/A to -R) containing various lengths of the WRN promoter region were cotransfected with p53 expressing pC53-SN3 (0.1 μg) in Saos2 cells, and the site of the WRN promoter that responds to p53 was investigated. Gray columns show WRN promoter activities associated with pGL3/A to -R alone; white columns show WRN promoter activities obtained in the presence of p53. The data were reproducible in two independent experiments. Luciferase activity is expressed as RLU (relative light units) as specified by the manufacturer (EG&G Bertholdo).