library_construction_protocol: Lysates were clarified from sonicated nuclei and protein-DNA complexes were isolated with antibody. DNA samples were end-repaired, A tailed, and adaptor ligated using TruSeq Nano DNA Sample Prep Kit (#FC-121-4002, Illumina), following the manufacturer's instructions. ~200-1500 bp fragments were size selected using AMPure XP beads. The final size of the library was confirmed by Agilent 2100 Bioanalyzer.