FIG. 7.

Rep inhibits p300-mediated stimulation of E2 transactivation. (A) Schematic representation of the reporter construct. The pTKM.32 construct contains only six E2-binding sites (6XE2BS) and a thymidine kinase (TK) promoter upstream of the CAT reporter gene followed by the simian virus 40 polyadenylation site (SV40pA) (68). (B) CAT assay. Cells transfected with the minimal E2-responsive promoter shown in panel A were cotransfected with plasmids expressing E2, Rep40, and p300, as indicated. Rep40 inhibited E2 activity, an effect that could be rescued by cotransfecting p300. Data are reported as means and standard deviations.