FIG 5.

WDHD1 plays a role at the G₁/S transition in E7-expressing cells. (A) RPE1 cells expressing E7 or containing a vector were transfected with siRNAs targeting WDHD1. The steady-state levels of WDHD1 were measured by Western blotting. Tubulin was used as a loading control. Right panel, quantification of relative WDHD1 levels from 3 independent experiments. (B) RPE1 cells were incubated with cycloheximide (CHX) and harvested at the indicated times. The stability of WDHD1 was monitored by immunoblotting analyses (left panel). Data are summarized in the right panel. (C) After siRNA transfection, cells were treated with bleomycin, stained with propidium iodide (PI), and analyzed by flow cytometry. Results of 1 experiment representative of 3 are shown (upper panel). The percentages of cells with 2C and 4C DNA content are indicated. Data are summarized in the lower panel. (D) After siRNA transfection, cells were treated with bleomycin, stained with BrdU, and analyzed by flow cytometry. Data of 3 independent experiments are summarized in the lower panel. *, P < 0.05; **, P < 0.01. NC, negative control.