Figure 6.

p53 stimulates the recovery of transcription after UV irradiation. (A) Cells were subjected to the temperature-shift protocols described in Table 1: 1 (▪), 2 (●), 3 (▴), and 4 (▾). At various times after UV irradiation, nascent RNA was labeled for 30 min with [³H]uridine. Polyadenylated RNA was isolated with the use of oligo-dT beads and quantified with a scintillation counter. (B) The expression of p21^WAF1 and Bax was assessed 6 h after UV irradiation by Western blot analysis in HT29-tsp53 cells subjected to the different temperature-shift protocols (Table 1). Expression of actin was used as a loading control.