Global gene-expression analyses of the Eset knock-down ES cells

The histone H3 lysine 9 (H3K9) methyltransferase Eset is an epigenetic regulator critical for the development of the inner cell mass (ICM). Although ICM-derived embryonic stem (ES) cells are normally unable to contribute to the trophectoderm (TE) in blastocysts, we find that depletion of Eset by shRNAs leads to differentiation with the formation of trophoblast-like cells and induction of trophoblast-associated gene expression. Using ChIP-seq analyses, we identified Eset target genes with Eset-dependent H3K9 trimethylation. We confirmed that genes that are preferentially expressed in the TE (Tcfap2a and Cdx2) are bound and repressed by Eset. Single cell PCR analysis shows that the expression of Cdx2 and Tcfap2a is also induced in Eset-depleted morula cells. Importantly, Eset-depleted cells can incorporate into the TE of a blastocyst and subsequently placental tissues. Co-immunoprecipitation and ChIP assays further demonstrates that Eset interacts with Oct4, which in turn recruits Eset to silence these trophoblast-associated genes. Our result suggests that Eset restricts the extraembryonic trophoblast lineage potential of pluripotent cells and links an epigenetic regulator to key cell fate decision through a pluripotency factor.

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Yuan P, Han J, Guo G, Orlov YL, Huss M, Loh YH, Yaw LP, Robson P, Lim B, Ng HH