The method for chromatin immunoprecipitation was described as ChIP assay kit (Cell Signaling Technology), while the agarose beads were replaced by magnetic beads. Indexed libraries were prepared from 6ng-20ng of Diagenode Biorupter sheared ChIP DNA using the KAPA Hyper Library Preparation Kit (Kapa Biosystems, Inc). Libraries were amplified by 6 cycles of PCR then assessed for quality using the Fragment Analyzer High Sensitivity NGS Fragment Analysis Kit (Advanced Analyticals) and quantified using the Qubit dsDNA HS Assay Kit (ThermoFisher).