design: For Hi-C assays, paraformaldehyde was applied for cell crosslinking to maintain DNA conformation and structure. The cells were lysed with the digestion of restriction enzyme MboI to generate sticky ends, the biotin-14-dCTP was introduced and tagged at the end of oligonucleotide during DNA repairing. The DNA fragments were ligated with DNA ligase. The proteins were digested to release the cross-linking state with DNA, then the labeled DNA was purified and randomly sheared into fragments of 300~500 bp. The biotin-containing DNA fragments were captured and PCR-enriched to construct a Hi-C library. The library was sequenced on the BGI T7 platform according to the PE150 strategy.