The Effect Of Meg8-DMR On Mouse Placenta Development

The Dlk1-Dio3 imprinted interval is one of the important imprinted gene clusters in the genome,and its location is at the end of chromosome 12 in mice.This imprinted interval is an important epigenetic regulatory region with three patriarchal marked protein-coding genes and multiple non-coding RNA genes expressed by mather.This area plays an important role in embryonic development,cell proliferation and differentiation,angiogenesis,and placental development..There are three differential methylation region of paternal methylation in this interval,namely Dlk1-DMR,Gtl2-DMR and IG-DMR,and a differential methylation Meg8-DMR of maternal methylation.The specific function of Meg8-DMR is still unknown,so exploring the regulatory role of Meg8-DMR in the Dlk1-Dio3 imprinted interval is extremely important for understanding the function of Meg8-DMR.The placenta,as a bridge between the mother and the fetus,is often affected by imprinted genes.Therefore,studying the effect of Meg8-DMR deletion on the placenta can be used as an important indicator to explore the regulatory mechanism of Meg8-DMR.This subject is based on the knockout mouse model constructed by the research group in the early stage using CRISPR / Cas9 technology,and four genotype mouse placenta,including the wild type(Meg8-DMR +/+),paternal deletion(Meg8-DMR +/-),maternal deletion(Meg8-DMR-/+)and homozygous type(Meg8-DMR-/-).First,the collected placenta tissue was fixed,embedded,sectioned,and HE stained to observe the morphological changes of the mouse placenta after Meg8-DMR knockout.Through statistical analysis,it was found that compared with the wild type,the paternal deletion group placenta of E12.5 days was lighter in weight,while the homozygous group in E15.5 days was heavier in weight,and the absence of Meg8-DMR has no significant effect on the distribution and morphology of the placenta.Secondly,RNA from placental tissue was extracted,and its c DNA was synthesized by reverse transcription.Semi-quantitative PCR and q RT-PCR were used to detect the expression levels of the relevant imprinted genes in the Dlk1-Dio3 imprinted interval.It can be seen that the Irm of the maternal deletion group and the homozygous group increased significantly.In summary,the absence of Meg8-DMR will have a certain effect on the placental weight of mice,and there is a certain time difference.At the molecular level,the deletion of Meg8-DMR does not affect the expression of major imprinted genes in the region,but it can be seen that the expression of Irm is significantly upregulated in Meg8-DMR-/+ and Meg8-DMR-/-mice.Studies have shown that Meg8-DMR may be used as a regulatory region of Rian to regulate the expression of neighboring genes.This study is helpful to understand the biological function of Meg8-DMR during development,and to further clarify the epigenetic regulatory mechanism of Meg8-DMR.