An in vitro ES cell imprinting model shows that imprinted expression of the Igf2r gene arises from an allele-specific expression bias.

摘要: Genomic imprinting is an epigenetic process that results in parental-specific gene expression. Advances understanding the mechanism regulates imprinted expression mammals have largely depended on generating targeted manipulations embryonic stem (ES) cells are analysed vivo mice. However, genomic consists of distinct developmental steps, some which occur post-implantation embryos, indicating they could be studied vitro ES cells. The mouse Igf2r shows only stages, when repression paternal allele has been shown to require cis-expression Airn non-coding (nc) RNA and correlate with gain DNA methylation repressive histone modifications. Here we follow during cell differentiation show it coincides onset paternal-specific ncRNA. Notably, although ncRNA leads, as predicted, marks promoter, unexpectedly find promoter expressed at similar low levels throughout differentiation. Our further maternal promoters equally undifferentiated cells, but increases up 10-fold, while from remains constant. This indicates, contrary expectation, induces not by silencing bias between two parental alleles.