Resource,Source,Identifier Anti-phospho-Histone H2A.X (Ser139) Antibody, clone JBW301,Millipore,RRID:AB_309864 Rabbit anti-PPP2R1A Antibody, Affinity Purified,Bethyl,RRID:AB_805812 Go-ChIP-Grade(TM) Purified anti-RNA Polymerase II RPB1,BioLegend,RRID:AB_2650945 Rabbit anti-INT3 Antibody, Affinity Purified,Bethyl,RRID:AB_1604271 DICE1 (H-6),Santa Cruz Biotechnology,RRID:AB_11151226 Anti-beta Tubulin antibody - Loading Control,Abcam,RRID:AB_2210370 Go-ChIP-Grade(TM) Purified anti-Histone H3 (C-terminus),BioLegend,RRID:AB_2832857 Rabbit anti-SSB1 Antibody, Affinity Purified,Bethyl,RRID:AB_1548027 Monoclonal Mouse anti‑Human NABP2 Antibody (clone OTI1E11),LSBio (LifeSpan),RRID:AB_3075492 U2OS,Cellosaurus,RRID:CVCL_0042 HEK293,Cellosaurus,RRID:CVCL_0045 HeLa,Cellosaurus,RRID:CVCL_0030 pFastBac-M2,Addgene,RRID:Addgene_135583 pGex4T1-JET,Addgene,RRID:Addgene_136245 pFastBac His6 MBP Asn10 TEV cloning vector with BioBrick PolyPromoter LIC Subcloning (438-C),Addgene,RRID:Addgene_55220 pCBASceI,Addgene,RRID:Addgene_26477 sigma-tau,http://www.sigma-tau.it/eng/,RRID:SCR_000488 Fiji,http://fiji.sc,RRID:SCR_002285 BEDTools,https://github.com/arq5x/bedtools2,RRID:SCR_006646 python-bx,https://github.com/bxlab/bx-python,RRID:SCR_024202 SciPy,http://www.scipy.org/,RRID:SCR_008058 ChIP-seq,https://gitlab.sib.swiss/EPD/chipseq,RRID:SCR_001237 SAMTOOLS,http://htslib.org/,RRID:SCR_002105 FlowJo,https://www.flowjo.com/solutions/flowjo,RRID:SCR_008520 ImageJ,https://imagej.net/,RRID:SCR_003070