FIG. 6.

Expression of B1 in trans enhances intermediate gene expression under permissive but not nonpermissive conditions. L929 cells were transfected with either pG8R-CAT alone or pG8R-CAT and pT7-B1 or pT7-ΔB1. After transfection, cells were infected with ts25T7 or VTF7.3 at the indicated temperatures. Lysates were prepared at 24 h after infection and assayed for CAT activity (expressed as percent acetylation). This experiment was conducted five separate times, and standard deviations are denoted over the bars.