Mechanism of TRRAP action. (A) TRRAP acetylation (Ac) of either mutp53 or DNA damage–stabilized wtp53 prevents nuclear export and facilitates accumulation within the nucleus. (B) Loss of TRRAP leads to XPO1-directed nuclear export and subsequent binding to MDM2, targeting either mutant or DNA damage–stabilized p53 for destruction via the ubiquitin (Ub)-proteasome pathway.