Cultured cells were fixed with 1% formaldehyde. Nuclei were isolated and the DNA was sheared to 200 to 300 bp fragments. Histon-bound DNA was precipitated using antibodies H3K27Ac (#4729, Abcam) and H3K4me3 (#04-745, Millipore). De-crosslinked DNA was purified using Qiagen PCR purification kit (Qiagen) and quantified with Quant-IT Picogreen (Invitrogen). The DNA was used to generate sequencing libraries according to the manufactures procedure (Life Technologies): The DNA was end-polished, dA-tailed and adaptors with barcodes were ligated. The fragments were amplified (8 cycles) and quantified with a Bioanalyzer (Agilent). The libraries were prepped with the 5500W Flowchip v2 kit (Life Technologies) and sequenced on the SOLiD Wildfire (Illumina) resulting in 50 bp reads. Alternatively, the libraries were sequenced using the HiSeq PE cluster kit v4 (Illumina) with the HiSeq2500 (Illumina) resulting in 125 bp reads.