The ATAC-seq assay was performed on 50,000 FACS-purified Purified cells were lysed in ATAC lysis buffer for 5 min to get nuclei and then transposed with Tn5 transposase (Illumina) for 30 min. Fractionated DNA was used for amplification and library preparation Illumina, Illumina HiSeq 4000, 150 bp-paired end sequencing