FIG. 6.

Highly purified e55K interacts with ep53 bound to DNA. (A) Two ³²P-labeled DNA fragments were used in the DNA immunoprecipitation assay, one containing five Gal4 binding sites (lanes 1 and 2) and one containing five p53 binding sites (lanes 3 to 7). ep53 (150 ng) was added to binding reaction mixtures in lanes 2, 4, and 6. e55K (150 ng) was added to binding reaction mixtures in lanes 6 and 7. ep53 was immunoprecipitated with an anti-p53 antibody, Ab421, and e55K was immunoprecipitated with the anti-55K antibody 2A6. (B) The ³²P-labeled DNA fragment containing five p53 binding sites was incubated with 150 ng of ep53 (lanes 2 and 3) and 150 ng of e55K (lane 3). Immunoprecipitation was with anti-p53 monoclonal antibody 421. For both panels A and B, immunoprecipitated DNA was resolved by PAGE and visualized by autoradiography.