Rif 1

The primary antibodies were: γH2AX (1:800, Upstate Technology, USA), 53BP1 (1:1000, Bethyl, Cambridge, UK), RPA (1:100 for IF, Calbiochem, USA), RAD51 (1:200 for IF and 1:500 for IB, Santa Cruz Biotechnology, USA), BRCA1 (1:100 for IF and 1:50 for IB, Santa Cruz), HP1(α,β,γ) (1:1000 for IB, Santa Cruz). HP1α (1:500 for IB, Santa Cruz), RIF-1 (1:1000 Bethyl, Cambridge, UK), SUV39H1/2 (1:300 for IB, Santa Cruz), SETDB1 (1:100 for IF, Abcam, UK, 1:1000 for IB, Cell Signalling Technology (CST), EXO1 and BLM (1:500, Santa Cruz), H3 (1:3000 Abcam, UK), H3K9 (1:3000 from Bethyl, Cambridge, UK), β-tubulin (1:3000, Sigma Aldrich, UK), HA tag (1:1000, Abcam) and mouse monoclonal anti-Actin (1:3000 from Sigma Aldrich, UK). The secondary antibodies were FITC (1:200, Sigma Aldrich, UK), Cy3 (1:200, Sigma Aldrich, UK) and Alexa Fluor 488 (1:400, Invitrogen, USA). Horseradish peroxidase (HRP) conjugated secondary antibodies were from Dako, UK.

Antibodies used in this study include: HA (C29F4, CST 3724), RIF1 (Santa Cruz, SC-65,191), EZH2 (CST, 5246), SETDB1 (Santa Cruz, sc-66,884), H3K9me3 (Abcam, ab8898), H3K4me3 (Active motif, 39,159), H3K27me3 (Active motif, 39,155), H3K9ac (Millipore, 07-352), H3K27ac (Active motif, 31,933), Suv39H1 (CST, 8729), EHMT2 (CST, 3306).