Figure 1

Expression of Mre11 rescues S-phase arrest in HCT116. HCT116 cells were transfected with a vector expressing Mre11 or an empty control vector and stable clones were selected. (A) Cells were lysed and Mre11, Rad50, Nbs1, and actin proteins were analyzed by western blot. The nine lanes on the right are derived from 9 independently-transfected clones. (B) HCT116 cells and two HCT116+Mre11 clones were incubated with 0-30 ng/ml SN38 for 24 h. Cells were fixed, stained with propidium iodide and analyzed for cell cycle distribution by flow cytometry.