A role for non-coding Tsix transcription in partitioning chromatin domains within the mouse X-inactivation centre.
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ABSTRACT: Background
Delimiting distinct chromatin domains is essential for temporal and spatial regulation of gene expression. Within the X-inactivation centre region (Xic), the Xist locus, which triggers X-inactivation, is juxtaposed to a large domain of H3K27 trimethylation (H3K27me3).Results
We describe here that developmentally regulated transcription of Tsix, a crucial non-coding antisense to Xist, is required to block the spreading of the H3K27me3 domain to the adjacent H3K4me2-rich Xist region. Analyses of a series of distinct Tsix mutations suggest that the underlying mechanism involves the RNA Polymerase II accumulating at the Tsix 3'-end. Furthermore, we report additional unexpected long-range effects of Tsix on the distal sub-region of the Xic, involved in Xic-Xic trans-interactions.Conclusion
These data point toward a role for transcription of non-coding RNAs as a developmental strategy for the establishment of functionally distinct domains within the mammalian genome.
SUBMITTER: Navarro P
PROVIDER: S-EPMC2720958 | biostudies-literature |
REPOSITORIES: biostudies-literature
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