FIGURE 4.

Lys-120 acetylation is required for p53 to displace the anti-apoptotic protein MCL-1 from BAK. A, H1299 cells expressing either p53 or the K120R mutant under the regulation of a tetracycline (TET)-response element were treated with 500 ng/ml tetracycline or vehicle for 24 h. After treatment, cells were collected and lysed to generate whole cell extracts. Whole cell extracts were the subjected to immunoprecipitation with BAK antibodies. BAK precipitates were then analyzed by Western blot with antibodies that recognize p53 or MCL-1. Input lysates were also blotted with p53, BAK, MCL-1, and actin antibodies. B, H1299 cells expressing either p53 or the K120R mutant under the regulation of a tetracycline-response element were treated with 500 ng/ml tetracycline or vehicle for 6 h. Following tetracycline treatment, cells were administered 0.5 μm adriamycin (Adr) or vehicle for an additional 18 h. After treatment, cells were collected and analyzed as in A. Unt, untreated.