ChIP for ETS1. Briefly, D0、D2、D5、D9、D14 of hESCs-derived cells were fixed using 1% formaldehyde for 10 min, and 0.125 M glycine was added to stop fixation. Cells were harvested, and DNA was fragmented to 300–500 bp by sonication with a Covaris S220 sonicator. Immunoprecipitation was performed with antibodies conjugated to Dynabeads Protein G beads (1004D, Life Technologies). ChIP DNA was eluted, reverse cross-linked, extracted with phenol/chloroform, and precipitated. For ChIP-Seq, 1 ng ChIP DNA or input DNA was used to generate sequencing libraries using the Nextera XT DNA sample preparation Kit (FC-131-1024,Illumina). Libraries were sequenced on the NextSeq500 sequencer (Illumina) using the 35nt paired-end sequencing protocol.