ABSTRACT: Severe damage on placental fetal capillary network causes mid to late fetal lethality and reduction of placental size in Peg11/Rtl1 KO mice [day 10.5]
Project description:Paternally expressed 11/Retrotransposon-like 1 (Peg11/Rtl1) knockout (KO) mice exhibited mid to late fetal lethality or late fetal growth retardation associated with frequent neonatal lethality. The lethal phenotype was largely dependent on genetic background and became more severe with each succeeding generation in the course of backcross experiments to C57BL/6 (B6). We previously suggested these lethal and growth phenotypes were due to severe defects in placental fetal capillaries in labyrinth layer. In this study, we reexamined KO fetuses exhibiting mid fetal lethality with internal bleeding. Importantly, basal region of fetal capillary network was specially damaged, therefore, also leading to poor expansion of the labyrinth layer and placental size reduction in later stage. Apparent up-regulation of Guanine nucleotide binding protein, alpha 2 (Gnai2) and decrement of Transmembrane protein 100 (Tmem100), Mesenchyme homeobox 2 (Meox2) and Lymphatic vessel hyaluronan Receptor 1 (LYVE1) expression were observed in earlier stage of placentas even before apparent morphological changes occurred, suggesting that these genes are involved in the maintenance of fetal capillaries associated with Peg11/Rtl1 in development.
Project description:Paternally expressed 11/Retrotransposon-like 1 (Peg11/Rtl1) knockout (KO) mice exhibited mid to late fetal lethality or late fetal growth retardation associated with frequent neonatal lethality. The lethal phenotype was largely dependent on genetic background and became more severe with each succeeding generation in the course of backcross experiments to C57BL/6 (B6). We previously suggested these lethal and growth phenotypes were due to severe defects in placental fetal capillaries in labyrinth layer. In this study, we reexamined KO fetuses exhibiting mid fetal lethality with internal bleeding. Importantly, basal region of fetal capillary network was specially damaged, therefore, also leading to poor expansion of the labyrinth layer and placental size reduction in later stage. Apparent up-regulation of Guanine nucleotide binding protein, alpha 2 (Gnai2) and decrement of Transmembrane protein 100 (Tmem100), Mesenchyme homeobox 2 (Meox2) and Lymphatic vessel hyaluronan Receptor 1 (LYVE1) expression were observed in earlier stage of placentas even before apparent morphological changes occurred, suggesting that these genes are involved in the maintenance of fetal capillaries associated with Peg11/Rtl1 in development.
Project description:Severe damage on placental fetal capillary network causes mid to late fetal lethality and reduction of placental size in Peg11/Rtl1 KO mice
Project description:Severe damage on placental fetal capillary network causes mid to late fetal lethality and reduction of placental size in Peg11/Rtl1 KO mice [day 12.5]
Project description:Germline epigenetic programming, including genomic imprinting, substantially influences offspring development. Polycomb Repressive Complex 2 (PRC2) plays an important role in Histone 3 Lysine 27 trimethylation (H3K27me3)-dependent imprinting, loss of which leads to growth and developmental changes in mouse offspring. In this study, we show that offspring from mouse oocytes lacking the PRC2 protein Embryonic Ectoderm Development (EED) were initially developmentally delayed, characterised by low blastocyst cell counts and substantial growth delay in mid-gestation embryos. This initial developmental delay was resolved as offspring underwent accelerated fetal development and growth in late gestation resulting in offspring that were similar stage and weight to controls at birth. The accelerated development and growth in offspring from Eed-null oocytes was associated with remodelling of the placenta, which involved an increase in fetal and maternal tissue size, conspicuous expansion of the glycogen enriched cell population and delayed parturition. Despite placental remodelling and accelerated offspring fetal growth and development, placental efficiency and fetal blood glucose levels were low, and the fetal blood metabolome was unchanged. Moreover, while expression of the H3K27me3-imprinted gene and amino acid transporter Slc38a4 was increased, fetal blood levels of individual amino acids were similar to controls, indicating that placental amino acid transport was not enhanced. Genome-wide analyses identified extensive transcriptional dysregulation and DNA methylation changes in affected placentas, including a range of imprinted and non-imprinted genes. Together, while deletion of Eed in growing oocytes resulted in fetal growth and developmental delay and placental hyperplasia, our data indicate a remarkable capacity for offspring fetal growth to be normalised despite inefficient placental function and the loss of H3K27me3-dependent genomic imprinting.
Project description:Sexual dimorphism in placental physiology during development affects the functionality of placental adaptation during adverse pregnancy, affecting fetal growth, development, and eventually fetal programming, which have long-term effects on the offspring’s adult life. However, studies focusing on the phenomenon and relationship between sex-specific placental adaptation and consequent altered fetal development are still elusive. Here, we established a prenatal maternal stress model by administering lipopolysaccharide (LPS) to pregnant ICR mice at the mid-gestational stage. To verify the appropriateness of the animal model to study sex differences in the sub-optimal uterus milieu, pregnancy complications were examined. To elucidate global transcriptomic changes occurring in the placenta, total RNA sequencing was performed in female and male placentas. LPS exposure at the mid-gestational stage induced placental inflammation in both sexes. In utero inflammatory conditions resulted in intrauterine fetal growth restriction and impaired placental development in a sex-specific manner depending on the dose of LPS. Sex-biased placental pathology was observed in the junctional zone and the labyrinth layer. Placental transcriptome analysis revealed widespread disparity in protein-coding and long non-coding genes between female and male placentas, presenting the relationship between morphology and function in a sex-specific IUGR model.
Project description:Microarray analysis of human fetal microglia from the mid-trimester period was performed. DEGs were identified between early and late stages of the mid-trimester gestation. Genes expressed in the human fetal microglia were also compared with mouse microglia core signature.
Project description:The goal of this study was to transciprtionally profile the three layers of the human placenta (decidua, fetal membrane and placental villi) from the mid-gestation healthy human placenta.
Project description:Folate is important for fetal development and growth, yet its role in placentation is understudied. Here we report that disrupting folate metabolism by the hypomorphic Mtrr mutation in mice causes morphological and functional defects in their placentas that correspond with early- and late-onset fetal growth restriction. Remarkably, Mtrr heterozygous males initiate inheritance of similar placenta phenotypes and fetal growth defects in their wildtype grandprogeny. An integrated genome-wide approach shows placental transcriptional change and epigenetic instability is caused by an intrinsic or ancestral Mtrr mutation, affecting genes important for placenta development and function (e.g., pregnancy specific glycoprotein (Psg)/Ceacams). Crucially, we establish a functional association between mouse placenta transcript levels and fetal size and identify a human PSG gene variant linked to birthweight. This study provides molecular insight into how folate metabolism influences placental development and attributes a potential multigenerational epigenetic mechanism to unexplained cases of fetal growth defects.
Project description:A family of vertebrate-specific microRNAs called the ESCC microRNAs regulates proliferation and differentiation of embryonic stem cells. The ESCC microRNAs arise from two genetic loci in mammals, the miR-290/miR-371 and miR-302 loci. While the miR-302 locus is found broadly among vertebrates, the miR-290/miR-371 locus is unique to eutherian species, suggesting a role in placental development. Here, we evaluate that role. A knockin reporter for the mouse miR-290 gene is expressed throughout the embryo until gastrulation, at which time it becomes specifically expressed in extraembryonic tissues and the germline. In the placenta, expression is limited to the trophoblast lineage, where it remains highly expressed until birth. Deletion of the miR-290 gene results in reduced trophoblast progenitor cell proliferation and a reduced DNA content in endoreduplicating trophoblast giant cells. A reduction in placental size precedes a reduction in fetal size and prenatal death of most knockout embryos. The vascular labyrinth shows disorganization with thickening of the barrier between maternal and fetal blood associated with reduced diffusion of a radioactive tracer. Multiple mRNA targets of the cluster miRNAs are upregulated. Together, these data uncover a critical function for the miR-290 in the regulation of a network of genes required for normal placental development, suggesting a central role for this microRNA cluster in the evolution of eutherian species.