Display Settings:

Format

Send to:

Choose Destination
See comment in PubMed Commons below
Nature. 2011 Apr 21;472(7343):370-4. doi: 10.1038/nature09872. Epub 2011 Apr 6.

Eutherian mammals use diverse strategies to initiate X-chromosome inactivation during development.

Author information

  • 1Mammalian Developmental Epigenetics Group, Institut Curie, CNRS UMR 3215, INSERM U934, Paris 75248, France.

Erratum in

  • Nature. 2011 Jun 9;474(7350):239-40.

Abstract

X-chromosome inactivation (XCI) in female mammals allows dosage compensation for X-linked gene products between the sexes. The developmental regulation of this process has been extensively investigated in mice, where the X chromosome of paternal origin (Xp) is silenced during early embryogenesis owing to imprinted expression of the regulatory RNA, Xist (X-inactive specific transcript). Paternal XCI is reversed in the inner cell mass of the blastocyst and random XCI subsequently occurs in epiblast cells. Here we show that other eutherian mammals have very different strategies for initiating XCI. In rabbits and humans, the Xist homologue is not subject to imprinting and XCI begins later than in mice. Furthermore, Xist is upregulated on both X chromosomes in a high proportion of rabbit and human embryo cells, even in the inner cell mass. In rabbits, this triggers XCI on both X chromosomes in some cells. In humans, chromosome-wide XCI has not initiated even by the blastocyst stage, despite the upregulation of XIST. The choice of which X chromosome will finally become inactive thus occurs downstream of Xist upregulation in both rabbits and humans, unlike in mice. Our study demonstrates the remarkable diversity in XCI regulation and highlights differences between mammals in their requirement for dosage compensation during early embryogenesis.

PMID:
21471966
[PubMed - indexed for MEDLINE]
PubMed Commons home

PubMed Commons

0 comments
How to join PubMed Commons

    Supplemental Content

    Icon for Nature Publishing Group
    Loading ...
    Write to the Help Desk