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The A-repeat links ASF/SF2-dependent Xist RNA processing with random choice during X inactivation.

ABSTRACT: One X chromosome, selected at random, is silenced in each female mammalian cell. Xist encodes a noncoding RNA that influences the probability that the cis-linked X chromosome will be silenced. We found that the A-repeat, a highly conserved element within Xist, is required for the accumulation of spliced Xist RNA. In addition, the A-repeat is necessary for X-inactivation to occur randomly. In combination, our data suggest that normal Xist RNA processing is important in the regulation of random X-inactivation. We propose that modulation of Xist RNA processing may be part of the stochastic process that determines which X chromosome will be inactivated.

SUBMITTER: Royce-Tolland ME

PROVIDER: S-EPMC4336797 | biostudies-literature | 2010 Aug

REPOSITORIES: biostudies-literature

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The A-repeat links ASF/SF2-dependent Xist RNA processing with random choice during X inactivation.

Royce-Tolland Morgan E ME Andersen Angela A AA Koyfman Hannah R HR Talbot Dale J DJ Wutz Anton A Tonks Ian D ID Kay Graham F GF Panning Barbara B

Nature structural & molecular biology 20100725 8

One X chromosome, selected at random, is silenced in each female mammalian cell. Xist encodes a noncoding RNA that influences the probability that the cis-linked X chromosome will be silenced. We found that the A-repeat, a highly conserved element within Xist, is required for the accumulation of spliced Xist RNA. In addition, the A-repeat is necessary for X-inactivation to occur randomly. In combination, our data suggest that normal Xist RNA processing is important in the regulation of random X- ...[more]

PMID: 20657585

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