A, Chromatin recruitment of indicated proteins at 0, 30, and 60 min after IR (10 Gy), examined with the corresponding primary antibodies; cell fractionation was performed as described in Materials and Methods. B, XRCC4, Ligase IV, and XLF levels in PC3 and TMPRSS2-ERG-expressing cells at the indicated times following IR. β-actin was used as a loading control. C, Chromatin recruitment of indicated proteins at 0, 30, and 60 min following IR (10 Gy). The data are representative of three independent experiments.