For ChIP-Seq, 5×107 ES cells (V6.5) were used per immunoprecipitation according to previously described protocols (Lee et al., 2006). ChIP-Seq libraries were prepared with Illumina's kit.For RNA-seq, ES cells (V6.5) were infected with lentivirus carrying either Non-targeting shRNA, Zic2, Mbd3 or Mta2 shRNA in the presence of 8 ug/ml of polybrene. 24 hours later, ES cells were selected with 2 ug/ml of puromycin for additional 48 hours and then were grown one passage off feeders for 30 min before harvesting. Total RNA was isolated with the RNeasy (74106 Qiagen) kit, treated with DNase I (M0303L NEB), and re-purified with RNeasy. For total RNA-seq analyses, total RNA was depleted of ribosomal RNA using Ribozero (Illumina) before library preparation performing Tru-seq sample prep (Illumina). ChIP-seq and RNA-seq libraries were prepared for sequencing using standard Illumina protocols