The transcriptional regulatory code of eukaryotic cells – insights from genome-wide analysis of chromatin organization and transcription factor binding

Control of eukaryotic gene expression involves combinatorial interactions between transcription factors and regulatory sequences in the genome. In addition, chromatin structure and modification states play key roles in determining the competence of transcription. The term ‘transcriptional regulatory code’ has been used to describe the interplay of these events in the complex control of transcription. With the maturation of methods for detecting in vivo protein–DNA interactions on a genome-wide scale, detailed maps of chromatin features and transcription factor localization over entire genomes of eukaryotic cells are enriching our understanding of the properties and nature of this transcriptional regulatory code. The rapidly growing number of maps has revealed the dynamic nature of nucleosome composition and chromatin remodeling at regulatory regions and highlighted some unexpected properties of transcriptional regulatory networks in eukaryotic cells.