PEG3 domain gene expression in maternal and foetal placenta in intrauterine growth restricted bovine foetuses.

We used a genetic (MIMT1(Del)) model of intrauterine growth restriction to investigate dysregulation of PEG3 domain gene expression in bovine foetal and maternal placenta. ZIM2, APEG3 and PEG3 expressions were similarly reduced in MIMT1(Del/) (WT) foetal placenta, suggesting coordinated regulation. Methylation of DNA CpG sites associated with these genes showed no differences, but differences in the levels of MIMT1 RNA methylation at three CpG sites were found in foetal placenta. Our data are consistent with the presence of a bidirectional promoter 5' of MIMT1 and suggest a regulatory role for the MIMT1 non-coding transcript. PEG3 domain expression on the maternal placenta side was not affected by the foetal mutation.