Journal: Cell reports
Article Title: Break-induced replication is activated to repair R-loop-associated double-strand breaks in SETX-deficient cells
doi: 10.1016/j.celrep.2025.116386
Figure Lengend Snippet: (A, B, and E) U2OS WT and SETX -KO EGFP-BIR reporter cells were infected with lentiviruses expressing MRE11 shRNA, CtIP shRNA, or vector. Three days were given to allow shRNA expression to achieve effective knockdown of each gene. For the end-resection assay (A), shRNA-treated cells were infected with I-SceI-expressing lentiviruses to induce DSBs. Two days after I-SceI infection, cells were harvested for the end-resection assay. To examine the pRPA2 level (B), shRNA-treated cells were treated with 10 Gy IR. Cell lysates were collected 1 h after IR, and Western blotting was performed using the indicated antibodies. For BIR efficiency analysis (E), shRNA-treated cells were infected with I-SceI-expressing lentiviruses to induce DSBs. The percentage of EGFP-positive cells was quantified by FACS analysis 5 days after I-SceI infection. Data are shown as mean ± SD of n = 3 biological replicates. (C) U2OS WT and SETX -KO EGFP-BIR reporter cells were infected with lentiviruses expressing XPF shRNA or vector. Three days later, cells were infected with I-SceI-expressing lentiviruses to induce DSBs. Inhibitor PFM01 (100 μM) or DMSO was applied to cells together with I-SceI lentiviruses. Two days after I-SceI infection, cells were harvested for the end-resection assay. Data are shown as mean ± SD of n = 3 biological replicates. (D) U2OS WT and SETX -KO EGFP-BIR reporter cells were infected with I-SceI-expressing lentiviruses to induce DSBs, and simultaneously treated with DMSO or inhibitor PFM39 (100 μM). Two days after I-SceI induction, cells were harvested for end resection assay, and the data are shown as mean ± SD of n = 3 biological replicates. (F and G) U2OS WT and SETX -KO EGFP-BIR reporter cells were infected with lentiviruses encoding BLM shRNA, DNA2 shRNA, EXO1 shRNA, or vector. Three days later, cells were then infected with I-SceI-expressing lentiviruses to induce DSBs for end resection assay (F), or treated with 10 Gy IR to examine the pRPA2 level (G). Data are shown as mean ± SD of n = 3 biological replicates. For the end resection assay shown in (A), (C), (D), and (F), ssDNA% was normalized to the I-SceI cleavage efficiency as indicated by γH2AX ChIP values.
Article Snippet: PFM39 , TargetMol Chemicals , T38709.
Techniques: Infection, Expressing, shRNA, Plasmid Preparation, Knockdown, Resection Assay, Western Blot