Figure 11

N-terminal and C-terminal sequences in p53 allow inhibition of GR. A, Schematic of p53 and p73 swap mutants in which N-terminal and C-terminal sequences have been swapped simultaneously. B, Saos-2 cells were transfected with the GR-responsive luciferase reporter GR-luc (200 ng), GR DNA (100 ng), and increasing amounts DNA encoding the indicated p53:p73 protein (50 – 1000 ng of each DNA). Transfected cells were treated with Dex (100 nM) as described earlier, and luciferase activity in transfected cell lysates was determined. Fold change in GR-luc activity is plotted (+/- s.e.m.) from multiple experiments compared to the activity of GR-luc alone, whose value is considered 1.0. C, Representative immunoblots show the level of each protein. D, (Left) Lysates from Saos-2 cells transiently expressing GR and the indicated p53/p73 swap mutants were immunoprecipitated with a GR antibody and examined by immunoblotting with an anti-Flag antibody (GR IP/Flag IB). Arrowheads indicate the position of the indicated p53/p73 swap mutant. The asterisk indicates the position of the antibody heavy chain used in the immunoprecipitation. (Right) Lysates were examined prior to immunoprecipitation to show the relative input amounts of each protein.