FIGURE 7.

ATRX activity regulates imprinted genes. In germ cells into the Igf2/H19 locus, Igf2 gene is silenced through insulator establishment by CTCF and only the H19 gene is expressed in maternal alleles. Whereas in the paternal allele the DMR is methylated preventing CTCF binding and impairing insulator activity allowing Igf2 transcription. On the other hand, in forebrain cells of postnatal mice, in the maternal allele, the H19 gene is silenced. MECP2 directs ATRX and cohesin recruitment to the DMR. MECP2 or ATRX depletion increases histones H3 and H4 acetylation which lead to changes in nucleosome occupancy and CTCF binding, causing an aberrant transcription of the H19 gene.