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An Xist-activating antisense RNA required for X-chromosome inactivation.

ABSTRACT: The transcriptional imbalance due to the difference in the number of X chromosomes between male and female mammals is remedied through X-chromosome inactivation, the epigenetic transcriptional silencing of one of the two X chromosomes in females. The X-linked Xist long non-coding RNA functions as an X inactivation master regulator; Xist is selectively upregulated from the prospective inactive X chromosome and is required in cis for X inactivation. Here we discover an Xist antisense long non-coding RNA, XistAR (Xist Activating RNA), which is encoded within exon 1 of the mouse Xist gene and is transcribed only from the inactive X chromosome. Selective truncation of XistAR, while sparing the overlapping Xist RNA, leads to a deficiency in Xist RNA expression in cis during the initiation of X inactivation. Thus, the Xist gene carries within its coding sequence an antisense RNA that drives Xist expression.

SUBMITTER: Sarkar MK

PROVIDER: S-EPMC4616153 | biostudies-literature |

REPOSITORIES: biostudies-literature

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Xist-mediated Chromosome Inactivation

Project description:This SuperSeries is composed of the SubSeries listed below.

2019-06-17 | GSE119607 | GEO

Xist-mediated Chromosome Inactivation

Project description:Xist-mediated Chromosome Inactivation

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