Topological domains in mammalian genomes identified by analysis of chromatin interactions.
|Title||Topological domains in mammalian genomes identified by analysis of chromatin interactions.|
|Publication Type||Journal Article|
|Year of Publication||2012|
|Authors||Dixon JR, Selvaraj S, Yue F, Kim A, Li Y, Shen Y, Hu M, Liu JS, Ren B|
|Date Published||2012 May 17|
|Keywords||Animals, Binding Sites, Cell Differentiation, Chromatin, Chromosomes, Embryonic Stem Cells, Evolution, Molecular, Female, Genes, Essential, Genome, Heterochromatin, Humans, Male, Mammals, Mice, Repressor Proteins, RNA, Transfer, Short Interspersed Nucleotide Elements|
The spatial organization of the genome is intimately linked to its biological function, yet our understanding of higher order genomic structure is coarse, fragmented and incomplete. In the nucleus of eukaryotic cells, interphase chromosomes occupy distinct chromosome territories, and numerous models have been proposed for how chromosomes fold within chromosome territories. These models, however, provide only few mechanistic details about the relationship between higher order chromatin structure and genome function. Recent advances in genomic technologies have led to rapid advances in the study of three-dimensional genome organization. In particular, Hi-C has been introduced as a method for identifying higher order chromatin interactions genome wide. Here we investigate the three-dimensional organization of the human and mouse genomes in embryonic stem cells and terminally differentiated cell types at unprecedented resolution. We identify large, megabase-sized local chromatin interaction domains, which we term 'topological domains', as a pervasive structural feature of the genome organization. These domains correlate with regions of the genome that constrain the spread of heterochromatin. The domains are stable across different cell types and highly conserved across species, indicating that topological domains are an inherent property of mammalian genomes. Finally, we find that the boundaries of topological domains are enriched for the insulator binding protein CTCF, housekeeping genes, transfer RNAs and short interspersed element (SINE) retrotransposons, indicating that these factors may have a role in establishing the topological domain structure of the genome.