Figure 4From: Resistance of mitochondrial p53 to dominant inhibitionDominant inhibitory effect of p53DD on transcription but not mitochondrial apoptosis. (A) Western immunoblot on 30 μg of total protein extract from HCT116 cells expressing vector-only or p53DD, documenting the expression levels of endogenous wt p53 and p53DD. p53DD was detected with antibody PAb421 (1:200); loading control β-actin was detected with anti-β-actin antibody diluted at 1:5000. (B) RT-PCR on total RNA prepared from the indicated cell lines at 24 h after mock-treatment or treatment with 375 μM 5FU. The primers were specific for the p53-regulated p21 transcript and for the gapdh transcript as a control. (C) Percentage of apoptosis in the indicated cell lines and at 48 h after mock-treatment or exposure to α-amanitin (10 μM; A), 5FU (375 μM; F), or both combined (FA). Apoptosis was measured by determining the numbers of cells with a sub-2n DNA content after PI staining, as described in Materials and methods.Back to article page