p53DINP1 (p53-dependent damage-inducible nuclear protein 1) encodes two proteins termed p53DINP1-α (27 kDa) and p53DINP1-β (18 kDa). p53DINP1 may regulate p53-dependent apoptosis throμgh phosphorylation at Ser46 and induction of p53AIP1. p53DINP1 is expressed in many tissues and induced by a variety of stress agents including UV stress, mutagenic stress, heat shock, and oxidative stress.