FIG. 1.

Exonuclease activities of p53 and p53 deletion mutants. wt p53 and p53 deletion mutants were expressed in High Five insect cells infected with recombinant baculovirus and purified by metal affinity chromatography as described in Materials and Methods. Peak fractions of all proteins were analyzed by SDS-PAGE (A), and 150 ng of each protein was tested for exonuclease activity by the ³H filter retention assay (B). Exonuclease III was used as a control. aa, amino acids. Lane M, markers. Numbers on the left in panel A are molecular masses in kilodaltons.