FIG. 7.

Functional interaction of T-Ag with two c-Jun deletion mutants. (A and B) Effects of c-Jun deletion mutants on T-Ag-mediated activation of JCV late promoter. A CAT reporter plasmid (7 μg) containing the JCV late promoter was transfected into U-87MG cells alone or in combination with c-Jun deletion mutants c-Jun (258-333) (A) or c-Jun (1-257) (B) and T-Ag expression plasmids, as described in legend to Fig. 1. The concentrations of expression plasmids are indicated at the bottom of the panels in micrograms per 60-mm-diameter plate. (C and D) Effects of c-Jun deletion mutants on T-Ag-mediated viral DNA replication. A replication-competent plasmid, pBLCAT₃-Mad-1L (5 μg) containing the regulatory region of the Mad-1 strain of JCV was transfected alone or in combination with c-Jun deletion mutants CMV-HA-c-Jun (258-333) (C) and CMV-HA-c-Jun (1-257) (D) and CMV-T-Ag expression plasmids into U-87MG cells. Plasmid concentrations used in transfections are indicated at the top of the panels in micrograms. In lane 1, pBLCAT3 plasmid digested with BamHI enzyme was loaded as a positive control. Both the replication assays and the quantitation of the bands corresponding to the replicated viral DNA were carried out as described in Materials and Methods. Representative data for DpnI assays are shown, with variability indicated by standard deviation. The total amount of DNA transfected into the cells in all four panels was normalized with appropriate empty vectors.