Cells were crosslinked, flash frozen, and sent to Active Motif. According to Active Motif protocol, cells were lysed, sonicated, and then DNA-protein complexes were isolated with antibodies. Samples were reverse-crosslinked and DNA was purified. Illumina libraries were prepared by Active Motif using standard consecutive enzymatic steps of end-polishing, dA-addition, and adaptor ligation. After 15 cycles of PCR amplification, the resulting DNA libraries were quantified and sequenced on Illumina NextSeq 500.