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PubMed · 11479595

Imprinted X inactivation maintained by a mouse Polycomb group gene.

J Wang·J Mager·Y Chen·E Schneider·J C Cross·A Nagy·T Magnuson
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Abstract

In mammals, dosage compensation of X-linked genes is achieved by the transcriptional silencing of one X chromosome in the female (reviewed in ref. 1). This process, called X inactivation, is usually random in the embryo proper. In marsupials and the extra-embryonic region of the mouse, however, X inactivation is imprinted: the paternal X chromosome is preferentially inactivated whereas the maternal X is always active. Having more than one active X chromosome is deleterious to extra-embryonic development in the mouse. Here we show that the gene eed (embryonic ectoderm development), a member of the mouse Polycomb group (Pc-G) of genes, is required for primary and secondary trophoblast giant cell development in female embryos. Results from mice carrying a paternally inherited X-linked green fluorescent protein (GFP) transgene implicate eed in the stable maintenance of imprinted X inactivation in extra-embryonic tissues. Based on the recent finding that the Eed protein interacts with histone deacetylases, we suggest that this maintenance activity involves hypoacetylation of the inactivated paternal X chromosome in the extra-embryonic tissues.

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AcetylationAnimalsCell CountCrosses, GeneticDosage Compensation, GeneticFemaleGenomic ImprintingGreen Fluorescent ProteinsHistone DeacetylasesHomozygoteLuminescent ProteinsMaleMiceMice, TransgenicMultigene FamilyPlacentaPlacental LactogenPolycomb Repressive Complex 2Polycomb-Group ProteinsRepressor ProteinsSex FactorsTransgenesTrophoblastsJournal ArticleResearch Support, U.S. Gov't, P.H.S.

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J Wang, J Mager, Y Chen, E Schneider, J C Cross, A Nagy, T Magnuson. 2001. Imprinted X inactivation maintained by a mouse Polycomb group gene.. https://doi.org/10.1038/ng574

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