library_construction_protocol: For ChIP-seq,cells were crosslinked with 1% formaldehyde for 10 min and quenched with glycine for 5 min at the room temperature. Fixed cells were sonicated and immunoprecipitated with the mixture of beads and antibody overnight at 4 ℃. ChIP-DNA was purified using PCR purification kit (Qiagen) and performed for qPCR using iTaq™ Universal SYBR® Green Supermix (Bio-Rad) on CFX96 (Bio-Rad). ChIP-seq libraries were prepared with Illumina's ChIP-seq sample prep kit (0801-0303). NEBNext® DNA Library Prep Master Mix Set for Illumina.