Mdm2ʹs Dilemma: To Degrade or To Translate p53?

In this issue of Cancer Cell, Gajjar et al. provide insight into how Mdm2 can both inhibit and enhance p53 activity. In the basal setting, Mdm2 binds p53 and promotes p53 degradation. Under stress conditions, ATM-dependent phosphorylation of Mdm2 results in its recruitment to p53 mRNA, thereby stimulating p53 translation.