Restoration of p53 delays IκB degradation.

<p>(A) Accumulated effect of p53 on ubiquitylated proteins. After transient transfection of p53 in A2780, OVCAR-3 and SKOV-3 cells, whole cell lysates were prepared and Western blot was carried out using antibodies specific to ubiquitin, p21, IκB, p53 and β-actin (as loading control). Experiments were performed in duplicate and a representative result is shown. (B) Confirmation of p53 activity after transient transfection of p53. ELISA was performed in triplicate and data are shown as mean ± SE. Dark gray bars indicate significance (p<0.05, paired Student's <i>t</i>-test) within each cell line. (C) The effect of p53 on proteasome activity. Assays were performed in triplicate and data are shown as mean ± SE. Dark gray bars indicate significance (p<0.05, paired Student's <i>t</i>-test) within each cell line. (D) Effects of p53 on ubiquitination of IκB. Immunoprecipitated IκB was immunoblotted using ubiquitin antibody. Experiments were performed in duplicate and a representative result is shown.