Imprinting and X chromosome counting mechanisms determine Xist expression in early mouse development

摘要: In mice, X inactivation is preceded by in cis Xist expression. Initially, normal female embryos express the paternal allele exclusively, preceding imprinted trophectoderm. Later expression of alleles random, random epiblast lineage. this study using uniparental embryos, we demonstrate that initially dictated solely parental imprinting, causing all alleles. Maternal remain repressed, irrespective chromosome number. At compacting morula stage, imprint erased, and mechanism counting chromosomes imposes appropriate with respect to Our results also suggest may itself be regulated a novel maternally expressed gene.