Methylation of the mouse Xist gene in sperm and eggs correlates with imprinted Xist expression and paternal X-inactivation.
Preferential paternal X-inactivation in the extra-embryonic tissues of the female mouse embryo is correlated with imprinted expression of the paternal allele of the Xist gene in pre-implantation development. Here we examine 11 CpG sites in Xist to determine whether differential methylation might be the molecular basis for imprinting. We find that three sites in the promoter region are methylated in eggs but not in sperm and that this differential methylation is maintained to the blastocyst stage when the paternal X-inactivation occurs. This is the first example of a primary gametic methylation imprint governing differential expression of parental alleles in pre-implantation embryos.
Zuccotti
M
M
Molecular Embryology Unit, University of London, UK.
Monk
M
M
D000818:Animals; D001483:Base Sequence; D001755:Blastocyst / Q000378:metabolism; D004247:DNA / Q000235:genetics / Q000378:metabolism; D017931:DNA Primers / Q000235:genetics; D004303:Dosage Compensation, Genetic; D005260:Female; D018507:Gene Expression Regulation, Developmental; D018392:Genomic Imprinting; D008297:Male; D008745:Methylation; D051379:Mice; D008969:Molecular Sequence Data; D010063:Ovum / Q000378:metabolism; D016133:Polymerase Chain Reaction; D011247:Pregnancy; D062085:RNA, Long Noncoding; D022661:RNA, Untranslated; D013094:Spermatozoa / Q000378:metabolism; D014157:Transcription Factors / Q000235:genetics*
D017931:DNA Primers; D062085:RNA, Long Noncoding; D022661:RNA, Untranslated; D014157:Transcription Factors; C077885:XIST non-coding RNA; D004247:DNA