Fig. 7
From: Regulation of Transcription Functions of the p53 Tumor Suppressor by the mdm-2 Oncogene
A possible mechanism of regulation of p53 transcription activities by mdm-2
The N terminus of p53 may be directly involved in DNA sequence-specific transactivation and sequence-independent transcription repression by wild-type p53 as well as transactivation by mutant p53. These effects may be mediated by interactions with TBP or TAFs using a few critical residues on p53. Mdm-2 interacts with the same critical residues of p53 with high affinity and blocks the interactions of p53 with the transcription machinery. The negative regulation of all three p53 activities are strictly dependent on physical interaction between the two proteins.