Cells were lysed in ChIP buffer (50 mM Tris-HCl pH 7.9, 150 mM NaCl, 1% Triron X-100, 0.5% NP-40, 5 mM EDTA pH 8.0, 1 mM PMSF and protease inhibitor) and chromatin was sonicated to ~200 bp with a Diagenode Bioruptor Libraries were prepared according to manufacturer's instructions (Illumina). Immunoprecipitated DNA was first end-repaired using End-It Repair Kit (Epicenter), tailed with an A using Klenow exo minus (NEB M0212), and ligated to custom adapters. Fragments of 300±100 bp were size-selected and subjected to ligation-mediated PCR amplification (LM-PCR), using Q5 polymerase (NEB M0530).