Figure 1.

Depletion of Cdc6 results in nonlethal cell cycle block in nontransformed cells, but cell cycle arrest and cell death in cancer cells. (A–F) Indicated cell types were transfected with 100 nM siLuc or siCdc6 for 72 h. Transfected cells were fixed and stained with PI, followed by FACS analysis of >10,000 cells per condition. Sub-G1 populations were calculated based upon all counts per sample; G1/S/G2/M populations were calculated from non–sub-G1 counts. Below each FACS profile, siRNA-treated cells were lysed and subjected to immunoblotting analysis with anti-Cdc6 or anti-GAPDH (loading control) antibody. Note: It is not possible to strictly distinguish G1 and early S phase cells or late S phase cells and G2/M cells by FACS analysis. Thus, G1 contains G1 and G1/S cells and G2/M contains late S and G2/M cells.