Other
12 Authors
- Ramani V,
- Yang F,
- Ma W,
- Hill A,
- Disteche CM,
- Duan Z,
- Ay F,
- Noble WS,
- Deng X,
- Blau CA,
- Berletch JB,
- Shendure J
First Author | Deng X | Year | 2015 |
Journal | Genome Biol | Volume | 16 |
Pages | 152 | PubMed ID | 26248554 |
Mgi Jnum | J:355972 | Mgi Id | MGI:7762064 |
Doi | 10.1186/s13059-015-0728-8 | Citation | Deng X, et al. (2015) Bipartite structure of the inactive mouse X chromosome. Genome Biol 16(1):152 |
abstractText | BACKGROUND: In mammals, one of the female X chromosomes and all imprinted genes are expressed exclusively from a single allele in somatic cells. To evaluate structural changes associated with allelic silencing, we have applied a recently developed Hi-C assay that uses DNase I for chromatin fragmentation to mouse F1 hybrid systems. RESULTS: We find radically different conformations for the two female mouse X chromosomes. The inactive X has two superdomains of frequent intrachromosomal contacts separated by a boundary region. Comparison with the recently reported two-superdomain structure of the human inactive X shows that the genomic content of the superdomains differs between species, but part of the boundary region is conserved and located near the Dxz4/DXZ4 locus. In mouse, the boundary region also contains a minisatellite, Ds-TR, and both Dxz4 and Ds-TR appear to be anchored to the nucleolus. Genes that escape X inactivation do not cluster but are located near the periphery of the 3D structure, as are regions enriched in CTCF or RNA polymerase. Fewer short-range intrachromosomal contacts are detected for the inactive alleles of genes subject to X inactivation compared with the active alleles and with genes that escape X inactivation. This pattern is also evident for imprinted genes, in which more chromatin contacts are detected for the expressed allele. CONCLUSIONS: By applying a novel Hi-C method to map allelic chromatin contacts, we discover a specific bipartite organization of the mouse inactive X chromosome that probably plays an important role in maintenance of gene silencing. |