Integrated Analysis of DNA Methylation and Gene Expression in Porcine Placental Development

Abstract

Proper placental development is crucial for the conceptus to grow and survive, because the placenta is responsible for transporting nutrients and oxygen from the pregnant female to the developing fetus. However, the processes of placental morphogenesis and fold formation remain to be fully elucidated. In this study, we used whole-genome bisulfite sequencing and RNA sequencing to produce a global map of DNA methylation and gene expression changes in placentas from Tibetan pig fetuses 21, 28, and 35 days post-coitus. Substantial changes in morphology and histological structures at the uterine–placental interface were revealed via hematoxylin–eosin staining. Transcriptome analysis identified 3959 differentially expressed genes (DEGs) and revealed the key transcriptional properties in three stages. The DNA methylation level in the gene promoter was negatively correlated with gene expression. We identified a set of differentially methylated regions associated with placental developmental genes and transcription factors. The decrease in DNA methylation level in the promoter was associated with the transcriptional activation of 699 DEGs that were functionally enriched in cell adhesion and migration, extracellular matrix remodeling, and angiogenesis. Our analysis provides a valuable resource for understanding the mechanisms of DNA methylation in placental development. The methylation status of different genomic regions plays a key role in establishing transcriptional patterns from placental morphogenesis to fold formation.

Exploring maternal-fetal interface with in vitro placental and trophoblastic models

“…The placenta also secretes progesterone ( Kolatorova et al, 2022 ) and alpha-fetoprotein ( Melamed et al, 2023 ), synthesized by the fetal liver, which inhibit the maternal immune response, allowing normal development of the fetus in the uterus without causing rejection. Furthermore, the placenta is a dynamic and multifaceted organ that supports the development and survival of the embryo and fetus ( Tan et al, 2023 ). It possesses anti-inflammatory properties ( Aggarwal et al, 2019 ), as well as antibacterial and anti-scar activity.…”