Research Paper Volume 4, Issue 12 pp 917—922

Figure 2. Ectopic expression of TS, RRM1 and RRM2 suppress senescence in MYC-depleted melanoma cells.

(A) Cells were infected three times with control vectors (3V) or with vectors expressing TS, RRM1 and RRM2 cDNAs (TRR). Forty-eight hours later, cells were infected again with control shRNA (CL) or MYC shRNA (M). 5 days after the second infection, cells were collected and total protein lysates were probed in western blotting with the antibodies indicated on the left. (B) Cells were infected as described above. Five days after infection dNTPs were extracted and quantified. dNTP amounts were normalized by the amounts detected in 3V-CL cells or TRR-CL cells. (C) Cells were infected as described in (A). Five days after infection, cells were processed to detect SA-β-Gal activity, or stained with H2AX-γ-specific antibodies and DAPI or were used in the comet assay. Percentage of positive cells is indicated. (D) Cells that were infected as was described in (A) were plated in 12-well plates and counted every day for 3 days. Numbers below the graph correspond to the days post-infection.