30 million cells were cross-linked with 1% formaldehyde for 10 min at room temperature, and reactions were stopped by adding glycine to a final concentration of 0.2 M. Chromatin was extracted and sonicated to 500 bp. EBF1 (sc-137065, Santa Cruz Biotechnology; H00001879-M01, Abnova) and EZH2 (#5246, Cell Signaling) antibodies were used for chromatin immunoprecipitation (ChIP). Input DNA from cells prior to immunoprecipitation were used to normalize ChIP-seq peak calling. ChIPed DNA (10 ng) was used for ChIP with DNA sequencing (ChIP-seq) library construction following manufacturer protocols (New England Biolabs).