Fig. 2: XRCC4 is required for the recruitment of RIG-I to DSB sites.

a HEK293T cells were transfected with empty vector or Flag-RIG-I. The cells were then lysed and immunoprecipitated with anti-Flag agarose beads. The beads were boiled and probed with indicated antibodies. b A549 cells were treated with IR (10 Gy, 1–2 h). Cells were lysed, and nuclear fractions were immunoprecipitated with anti-RIG-I antibody. The beads were treated with RNase A, boiled and blotted with indicated antibodies. c Control and XRCC4 knockdown ER-AsiSI U2OS cells were transfected with Flag-RIG-I, and then treated with 4-OHT to induce DSBs. Flag-RIG-I accumulation at DNA damage sites generated by AsiSI was detected by ChIP-qPCR. Data are presented as mean values ± SEM from three independent experiments. P values are determined by unpaired two-sided t-test. d Control and XRCC4 knockdown HEK293T cells overexpressing RIG-I were transfected with NHEJ reporter, and then cells were harvested for the NHEJ assay. Data are presented as mean values ± SEM from three independent experiments. P values are determined by unpaired two-sided t-test.