Transcriptional repression in ES cells.

The dynamics of embryonic stem cell pluripotency is orchestrated by an interplay of transcriptional and epigenetic regulation in a systematic and modular manner. While the ES cell stage is marked by multiple loci with bivalent chromatin marks that prepare genes for imminent activation on differentiation, this open chromatin conformation is tempered by repressive machinery that prevent premature expression of key developmental genes. This review serves to highlight key ES transcription factors and their known links to the epigenetic machinery via known protein complexes.