Figure 3.

Cdc6 in E7-expressing cells is stabilized with bleomycin treatment, and its abundance is not cell cycle related. RPE1 cells expressing E7 or vector were treated with PBS or bleomycin (5 µg/ml for 48h). (A) Cdc6 (upper panel) and E7 (lower panel) levels were examined by immunoblotting. (B) After bleomycin treatment, the cells were incubated with 25 µg/ml cycloheximide (CHX) and harvested at the indicated times. The stability of Cdc6 was monitored using immunoblotting. The data from at least of two independent experiments are shown in the upper panel and summarized in the lower panel. (C) RPE1 E7 cells were blocked with 2.5M thymidine for 16h and then released to regular media and collected at the time points indicated. Cdc6 levels were determined (upper panel), and the cell cycle profile was analyzed. The data from a representative of four independent experiments are shown. AS, asynchronous.