Epigenetic dynamics of imprinted X inactivation during early mouse development.
The initiation of X-chromosome inactivation is thought to be tightly correlated with early differentiation events during mouse development. Here, we show that although initially active, the paternal X chromosome undergoes imprinted inactivation from the cleavage stages, well before cellular differentiation. A reversal of the inactive state, with a loss of epigenetic marks such as histone modifications and polycomb proteins, subsequently occurs in cells of the inner cell mass (ICM), which give rise to the embryo-proper in which random X inactivation is known to occur. This reveals the remarkable plasticity of the X-inactivation process during preimplantation development and underlines the importance of the ICM in global reprogramming of epigenetic marks in the early embryo.
Okamoto
Ikuhiro
I
CNRS UMR218, Curie Institute, 26 rue d'Ulm, Paris 75005, France.
Otte
Arie P
AP
Allis
C David
CD
Reinberg
Danny
D
Heard
Edith
E
D000107:Acetylation; D000818:Animals; D001755:Blastocyst / Q000502:physiology; D001757:Blastomeres / Q000502:physiology; D002843:Chromatin / Q000378:metabolism; D033481:Chromosomes, Mammalian / Q000502:physiology; D004303:Dosage Compensation, Genetic; D004622:Embryo, Mammalian / Q000502:physiology*; D005314:Embryonic and Fetal Development; D044127:Epigenesis, Genetic; D005260:Female; D018392:Genomic Imprinting; D006657:Histones / Q000378:metabolism; D008297:Male; D008745:Methylation; D051379:Mice; D009028:Morula / Q000502:physiology; D062085:RNA, Long Noncoding; D022661:RNA, Untranslated / Q000378:metabolism; D014158:Transcription, Genetic; D014960:X Chromosome / Q000502:physiology*
D002843:Chromatin; D006657:Histones; D062085:RNA, Long Noncoding; D022661:RNA, Untranslated; C077885:XIST non-coding RNA