library_construction_protocol: Cells were fixed with 1% formaldehyde for 10 min.After qunenching and cell lysis, chromatin was sonicated. ChIP-seq libraries were constructed with ChIP and input DNA using VATHS Universal DNA Library Prep Kit for Illumina (Vazyme ND606). Briefly, 50 μL of DNA (8-10 ng) was end-repaired for dA tailing, followed by adaptor ligation. Each adaptor was marked with an 8-bp DNA barcode. Adaptor-ligated DNA was purified by AMPure XP beads (1:1) and then amplified by PCR of 9 cycles with the primer matching with adaptor universal part. Amplified DNA was purified again using AMPure XP beads (1:1) in 35 μL EB elution buffer. For multiplexing, libraries with different barcodes were mixed with equal molar quantities (30-50 million reads per library). Libraries were sequenced by Illumina Nova-seq platform with pair-end reads of 150 bp.