GEN1 is required for HR of DNA DSBs. A.

<p>48 h following siRNA treatment with the indicated siRNAs U20S/DR-GFP cells were transfected with I-SceI plasmid for 48 h. Cells were processed for flow cytometric analysis of GFP, and the extent of HR was scored as the number of GFP-positive cells. Graph represents the mean of three independent experiments. Error bars indicate S.E.M. <b>B.</b> HeLa cells treated with CTRL or GEN1 siRNA (48 h) were fixed in ice-cold acetone–methanol (1∶1) and immunostained with GEN1 and γ-H2AX. Scale bar, 100 µm. Graph represents the mean of three independent experiments. (n = 100 cells/condition/experiment). Error bars indicate S.E.M. <b>C.</b> HeLa cells were treated with CTRL or GEN1 siRNA for 48 h. After fixation in ice-cold acetone–methanol (1∶1), half the cells were immunostained with γ-H2AX and afterwards all cells were incubated with secondary antibody. The samples were then analyzed by flow cytometry and WinMDI software.