Both DNA binding domains of p53 are required for its ultra-rapid recruitment to sites of UV damage

p53 concentrates at DNA damage sites within two seconds upon UV laser micro-irradiation. Structural analysis shows that this very rapid response requires both the DNA binding and C-terminal domains of p53. This early recruitment response is also PARP-dependent. As mutations within the DNA binding domain of p53, that are commonly associated with cancer also inhibit this rapid binding, we suggest that this is an important initial step for p53 function as a tumor suppressor. One Sentence Summary p53 is an early responder to DNA damage