Transcriptional Regulatory Networks in Embryonic Stem Cells

摘要

Embryonic stem (ES) cells are characterized by their ability to self-renew and remain pluripotent. Transcription factors havecritical roles in the maintenance of ES cells through specifying an ES-cell-specific gene expression program. Deciphering thetranscriptional regulatory network that describes the specific interactions of these transcription factors with the genomic tem-plate is crucial for understanding the design and key components of this network. Recent advances in genomic technologieshave facilitated genome-wide disclosure of the repertoire of transcription-factor-binding sites. Transcription factor colocal-ization hot spots targeted by multiple transcription factors have been identified. These are sites that integrate the external sig-naling pathways to the transcriptional regulatory circuitry governed by Oct4, Sox2, and Nanog. In addition, these sites mayserve as focal points for the assembly of nucleoprotein complexes known as enhanceosomes. Studying the properties of ES-cell-specific enhanceosomes in different pluripotent cells will shed light on the composition and regulation of their activity.Knowledge of the transcriptional regulatory networks in different pluripotent cells will also help to distinguish the core andperipheral parts of the networks. Collectively, these studies will facilitate the understanding of molecular mechanisms behindtranscription-factor-mediated regulation of pluripotent stem cells.