Instrument: Illumina HiSeq 1500
Strategy: ChIP-Seq
Source: GENOMIC
Selection: ChIP
Layout: SINGLE
Construction protocol: For ChIP-seq assays, cells were fixed in 1.5% formaldehyde (Sigma F8775) for 10 min at room temperature, the reaction was stopped by the addition of glycine (100 mM). Cells were lysed in lysis buffer (150 mM Tris-HCl pH 8.1, 10 mM EDTA, 0.5% Empigen BB, 1% SDS, protease inhibitor cocktail (Roche 5056489) and sonicated using a bioruptor (Diagenode, 15 min 30 sec ON /30 sec OFF). Sonicated chromatin was incubated at 4°C overnight with antibodies (ERa: mix of TE111.5D11 from Abcam and HC-20 from Santa Cruz Biotechnology, H3K4me3: 04-745 from Millipore, H3K27me3: 07-449 from Millipore) in IP buffer (2.8 ng/mL yeast tRNA, 20 mM Tris-HCl, 2 mM EDTA, 150 mM NaCl, 1% Triton X-100, proteases inhibitor cocktail). Complexes were recovered after 4h incubation with 45 mL protein A- and 15 mL protein G-conjugated sepharose beads slurry at 4°C. Beads were washed in washing buffers WB1 (20 mM Tris-HCl pH 8, 2 mM EDTA, 150 mM NaCl, 0.1% SDS, 1 % Triton X-100), WB2 (20 mM Tris-HCl pH 8, 2 mM EDTA, 500 mM NaCl, 0.1% SDS, 1 % Triton X-100), WB3 (10 mM Tris-HCl pH 8, 1 mM EDTA, 250 mM LiCl, 1 % deoxycholate, 1 % NP-40), WB4 (10 mM Tris-HCl pH 8, 1mM EDTA) and DNA fragments were eluted in extraction buffer (1% SDS, 0.1 M NaHCO3). For RNA-seq, total RNAs were extracted with the RNeasy Plus kit from QIAGEN including a DNase digestion step, and mRNA were enriched by selection with poly-dT beads. For SCL-exo-seq, genomic DNA was extracted using reagents from the DNeasy Blood and Tissue kit (QIAGEN). ChIP-seq libraries (2 replicates) were generated with DNA fragments from 6 to 9 pooled individual ChIP experiments and the TruSeq kit from Illumina according to the manufacturer's protocol. For RNA-seq, three replicate libraries of each condition (TruSeq stranded mRNA, Illumina) were prepared and sequenced (single reads of 75 bases) at the Genomic Paris Center facility (Paris, France). For each SCL-exo experiment, 8 micrograms of gDNA were sonicated two times 7 min (30 sec ON /30 sec OFF) and two times 14 min (30 sec ON /30 sec OFF) with a bioruptor (Diagenode). Glucosylation and biotinylation of 5hmC were performed with the Hydroxymethyl Collector kit (Active Motif), followed by on beads-exonuclease digestion of the captured fragments and library preparation (TrueSeq library preparation kit, Ilumina). For normalization purpose, 400 pg of 5hmC Control DNA provided by the Hydroxymethyl Collector kit were added to each sample as spike-in. Libraries from 3 independent SCL-exo experiments were sequenced with a HiSeq 1500 (Illumina) by the GEH facility (Rennes, France).