Chromosomal silencing and localization are mediated by different domains of Xist RNA

@article{Wutz2002ChromosomalSA,
  title={Chromosomal silencing and localization are mediated by different domains of Xist RNA},
  author={Anton Wutz and Theodore P. Rasmussen and Rudolf Jaenisch},
  journal={Nature Genetics},
  year={2002},
  volume={30},
  pages={167-174}
}
The gene Xist initiates the chromosomal silencing process of X inactivation in mammals. Its product, a noncoding RNA, is expressed from and specifically associates with the inactive X chromosome in female cells. Here we use an inducible Xist expression system in mouse embryonic stem cells that recapitulates long-range chromosomal silencing to elucidate which Xist RNA sequences are necessary for chromosomal association and silencing. We show that chromosomal association and spreading of Xist RNA… 

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TLDR
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Xist RNA and the mechanism of X chromosome inactivation.
TLDR
The authors are on the threshold of discovering the factors that regulate and interact with Xist to control X-inactivation, and closer to an understanding of the molecular mechanisms that underlie this complex process.
Spen links RNA-mediated endogenous retrovirus silencing and X chromosome inactivation
TLDR
It is shown that Spen, an Xist-binding repressor protein essential for XCI , binds to ancient retroviral RNA, performing a surveillance role to recruit chromatin silencing machinery to these parasitic loci.
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