library_construction_protocol: Cells were crosslinked with formaldehyde for 10 minutes and quenched with glycine. After sonication, lysates were applied to pre-washed anti-FLAG magnetic beads and incuated for 3h. After washed, beads were washed and DNA-protein complex were eluted. After reverse crosslinking and proteinase K treatment at 65˚C overnight, ChIP DNA was cleaned up using Zymo ChIP DNA clean & concentrator kit. ChIP-seq libaray was prepared using Illumina DNA prep kit and IDT 10bp UDI indices