The Parental Non-Equivalence of Imprinting Control Regions during Mammalian Development and Evolution
Figure 1
Methylation patterns in maternal-imprint free 0P and complete-imprint free 00 embryos at 8.5dpc.
A, Bisulfite genomic sequencing of ICRs associated with the H19 and Kcnq1ot1 loci. The paternally methylated H19 ICR was methylated in wildtype (MP) and in maternal imprint-free (0P) but unmethylated in imprint-free (00) visceral yolk sacs. The maternal Kcnq1ot1 ICR was hypomethylated in both 0P and 00 material, in agreement with the lack of maternal imprints in these embryos. Nucleotide positions are reported in reference to the gene transcription start (+1). B, Normal methylation of LINE1 and IAP retrotransposons in MP, 0P, and 00 8.5dpc embryos as established by DNA blot hybridization after cleavage with the methylation-insensitive restriction endonuclease MspI or the methylation sensitive isoschizomer HpaII.