Journal: The Journal of Cell Biology
Article Title: HP1α recruitment to DNA damage by p150CAF-1 promotes homologous recombination repair
doi: 10.1083/jcb.201101030
Figure Lengend Snippet: HR-mediated DSB repair is impaired by depletion of p150CAF-1, HP1α, and KAP-1. (A) Defective recruitment of RAD51 after depletion of p150CAF-1, HP1α, or KAP-1. We transfected U2OS cells with the indicated siRNAs and treated the cells as in , with CSK + Triton X-100 permeabilization and fixation within 5 min after laser-induced DNA lesions. We subsequently performed immunostaining with antibodies against RAD51 and γH2AX. DNA was stained with DAPI. Bars, 10 µm. (B) HR-mediated gene conversion is impaired after depletion of p150CAF-1, HP1α, or KAP-1. We analyzed the frequency of HR-mediated DNA repair events in U2OS+DR-GFP cells transfected with the indicated siRNAs. Each value shown corresponds to the percentage of HR relative to the control (sicont) and represents the mean of three independent experiments. The error bars represent the standard deviation of the mean. (C) Cell cycle profile of siRNA-transfected cells. In parallel, we monitor the cell cycle status of the siRNA-treated cells by flow cytometry analysis. (D) Confirmation of siRNA-mediated depletion. We performed immunoblotting to confirm that the indicated siRNA-mediated depletions were efficient in experiments from B. We used RAD51 as loading control. (E) Phosphorylation of the middle subunit of RPA is affected after depletion of HP1α. We transfected U2OS cells with the indicated siRNAs. 48 h later, we treated the cells with 1 µM camptothecin (CPT). At the indicated time points, we harvested the cells and performed immunoblotting with antibodies against RPA32, RPA32 S4/S8, HP1α, and CtIP. We used α-tubulin as loading control. (F) Defective recruitment of BRCA1 after depletion of HP1α. We transfected U2OS cells with the indicated siRNAs and treated the cells as in , with CSK + Triton X-100 permeabilization and fixation within 5 min after laser irradiation. We subsequently performed immunostaining with antibodies against BRCA1 and γH2AX. DNA was stained with DAPI. Bars, 10 µm.
Article Snippet: Rabbit anti-53BP1 (IB and IF, 1:500; NB 100-304; Novus Biologicals; ); mouse anti–pyrimidine 6,4-pyrimidone photoproduct (6,4-PP; IF, 1:1,000; KTM50; Kamiya Biomedicals; ; ) after 10 min of denaturation in 4 M HCl at RT before blocking; rabbit anti-ATM phospho-Ser1981 (IB and IF, 1:500; 600-401-398; Rockland; ); mouse anti-BRCA1 (IF, 1:500; Ab-1 [EMD] and ab16781 [Abcam]; ); rabbit anti–mouse p60CAF-1 (IF, 1:500; AgroBIO; ); rabbit anti–human p60CAF-1 (IF, 1:250; AgroBIO; ); rabbit anti–mouse p150CAF-1 (IF, 1:1,000; AgroBIO; ); mouse anti–human p150CAF-1 (IB and IF, 1:1,000; ab7655; Abcam; ); mouse anti–cyclobutane pyrimidine dimer (CPD; IF, 1:2,000; KTM53; Kamiya Biomedicals; ; ) after 5 min of denaturation in 0.5 M NaOH at RT before blocking; mouse anti-Chk1 (IB, 1:500; sc-8408; tebu-bio); rabbit anti-Chk1 phospho-Ser317 (IB, 1:1,000; 2344; Cell Signaling Technology; ; ); mouse anti-Chk2 (IB, 1:500; ab3292; Abcam; ); rabbit anti-Chk2 phospho-Thr68 (IB, 1:1,000; 2661; Cell Signaling Technology; ); mouse anti-CtIP (IB, 1:50; provided by R. Baer; ); rabbit anti-FANCD2 (IB, 1:1,000; IF, 1:500; NB 100-182; Novus Biologicals; ; ); rabbit anti-FANCD2 (IB, 1:1,000; IF, 1:500; ab2187; Abcam; ); mouse anti-GFP (IF, 1:500; 11 814 460; Roche; ); rabbit anti-GFP (IF, 1:1,000; 8372; Takara Bio Inc.); mouse anti–H2A-ub (IF, 1:500; 05-678; Millipore; ; ); rat anti-HA (IF, 1:250; 11 867 431 001; Roche); mouse anti-γH2AX (IF- 1:2,000; 05-636; Millipore; ); rabbit anti-γH2AX (1:500; 07-164; Millipore; ; ); rabbit anti-H3K9me3 (IF, 1:500; 07-442; Millipore; ; ); mouse anti-HP1α (IF, 1:1,000; 2HP-1H5-AS; Euromedex; ); rabbit anti-HP1α (IB, 1:1,000; IF, 1:2,000; H-2164, Sigma-Aldrich; ); mouse anti-HP1β (IF, 1:1,000; 1MOD-1A9; Euromedex; ; ); mouse anti-HP1γ (IF, 1:1,000; 2MOD-1G6; Euromedex; ; ); rabbit anti–KAP-1 (IB and IF, 1:500; A300-274; Bethyl Laboratories, Inc.; ); goat anti-Ku80 (IF, 1:500; sc-1484; Santa Cruz Biotechnology, Inc.; ; ); sheep anti-MDC1 (IF, 1:500; GTX 10948; GeneTex; ; ); rabbit anti-NBS1 phospho-Ser343 (IF, 1:500; NB 100-284; Novus Biologicals; ); rabbit anti-p53 phospho-Ser15 (IB, 1:500; 9284; Cell Signaling Technology; ; ); rabbit anti–human RAD51 (IB, 1:1,000; IF, 1:500; PC130; EMD; ); rabbit anti-RPA32 (IB, 1:500; 691-P1ABX; Neomarkers); rabbit anti-RPA32 phospho-Ser4/Ser8 (IB, 1:1,000; A300-245A; Bethyl Laboratories Inc.); rabbit anti-XRCC4 (IF, 1:500; ab2857; Abcam; ); rabbit anti-XRCC4 (IB, 1:1,000; AHP387; Serotec; ); and mouse α-tubulin (IB, 1:20,000; T 9026; Sigma-Aldrich), which was used as loading control.
Techniques: Transfection, Immunostaining, Staining, Standard Deviation, Flow Cytometry, Western Blot, Irradiation