library_construction_protocol: ChIP experiments and ChIP-Seq libraries were prepared using Diagenode True MicroChIP kit according to the manufacturer's protocol. 0.2 million freshly sorted Oct4-GFP+/KIT- or Oct4-GFP+/KIT+ cells were cross-linked with 1% formaldehyde for 10 minutes. The crosslinking was stopped by incubation with 0.125M glycine at room temperature for 5 minutes. Chromatin was fragmented to 200 to 600 bp by sonication using a Bioruptor sonicator (Diagenode, Liège, Belgium). 1ug antibodies against H3K4me3 or H3K27me3 were used for ChIP. Half of the chromatin was used for each IP, and 10% of the chromatin solution was reserved as input control. The chromatin immunoprecipitated (ChIPed) DNA was subjected to library preparation using MicroPlex Library Preparation kit (Diagenode, Liège, Belgium). The prepared library was sequenced with single-end 50bp reads using the Illumina HiSeq 2000.