The wild type p53 tumor suppressor protein transactivates genes carrying p53 responsive elements and represses several TATA containing promoters. We report in vivo gene regulation assays where deletion of the N-terminal 75 residues (ΔN75) results in loss of transactivation of p53CON and repression of an HPV 6 reporter. In contrast, removal of the C-terminal 75 (ΔC75) amino acids resulted in a truncated protein capable of trans-activating p53CON but not able to repress the HPV 6 reporter. In vitro protein association assays revealed that the ΔN75 protein, but not the ΔC75 truncated protein, could oligomerize with the wild type p53 protein. Co-transfection assays with wild type p53 showed that the ΔN75 mutant protein has a dominant negative effect on trans-activation function. However, it does not affect the ability of wild type p53 to repress transcription from the HPV 6 reporter. The ΔC75 protein had no effect on the ability of the wild type p53 to activate p53CON or repress the HPV 6 reporter. These results suggest that distinct regions of p53 have a differential role in transcriptional activation and repression functions.
|Original language||English (US)|
|Number of pages||7|
|Publication status||Published - Mar 1994|
ASJC Scopus subject areas
- Molecular Biology
- Cancer Research