Figure 5.

Models for selective p53 binding. In the model presented in (A), the formation of p53 binding patterns is driven by the binding affinity of p53 for RE sequences. It is proposed that p53 binding affinity to REs is modulated by stress-specific posttranslational modifications that favor binding to certain REs (red). In this model, p53 binding patterns should be observed on naked DNA. However, in our experimental setting, p53 binding patterns were virtually identical on naked DNA following the different treatments tested. We thus propose another model (B) where the affinity of p53 for specific RE sequences is not modulated differently following stresses, rather, the selectivity of p53 binding is dependent on the remodeling of chromatin (e.g. histone acetylation) at certain REs (red).