Figure 3.

Overview of the Nucleolar-Related, Stress-Induced Mechanisms that Result in Increased p53 Activity

The different mechanisms have been separated into three broad categories, namely those that primarily involve either (A) alterations of protein-protein interactions, (B) changes to the translational profile, or (C) prevention of coribosomal export of p53 and Hdmd2. The size of each quadrant represents their relative importance according to current literature. Grayscale text and objects indicate processes that occur during normal physiological conditions, whereas orange text and objects show the changes that occur following stress that result in increased p53 levels and activity. The outcomes of increases p53 are summarized in (D), namely the upregulation of p53 target genes which ultimately leads to either cell-cycle arrest or apoptosis, and the inhibition of ribosome biogenesis via the inhibition of rRNA transcription. Refer to text for detailed explanations of these pathways and for references.