Fig. 3. The Hes1 promoter is repressed by N-CoR, and this effect is reversed by p65-NFB overexpression. (A) N-CoR represses N1-IC activation of the Hes1 promoter. Indicated amounts of N-CoR were cotransfected with N1-IC expression vector (0.5 µg) into NIH-3T3 cells. (B) p65TA can revert inhibition mediated by N-CoR. Increasing amounts of p65TA were cotransfected with N1-IC (0.5 µg) and N-CoR (2 µg). Luciferase activity is presented as the fold induction relative to the basal level measured in cells transfected with empty vector. The average and standard deviation of duplicates from a representative experiment are presented. (C) Hes1 expression in 293T cells transfected with N2-IC and N-CoR expression vectors or coexpressed with p65wt is shown in the upper panel. Expression of N2-IC plasmid to compare transfection efficiency is shown in the lower panel.