BCL6 is a primary target of p53. H1299 cells expressing the ts-p53Val135 were used to identify p53 target genes. The mRNA levels were determined using DNA microarrays and the ratios were calculated by dividing the expression level at each time point by that of the respective control cells. Ctr indicates control cells of H1299 devoid of p53 after 2 hours at 32°C; h, number of hours after shifting the temperature to 32°C; +CHX/-CHX, presence or absence, respectively, of exposure to 10 μg/μL cycloheximide 30 minutes prior to temperature shift to 32°C. □ indicates control.