Fetal growth delay caused by loss of non-canonical imprinting is resolved late in pregnancy and culminates in offspring overgrowth
- Monash University, Australia
- University of Adelaide, Australia
- University of Melbourne, Australia
- La Trobe University, Australia
- St. Vincent's Hospital, Australia
Abstract
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.
Data availability
All RNA sequencing and RRBS data have been deposited to the Gene Expression Omnibus (GEO) and are publicly available with accession number GSE210398. The metabolomics data are available at the NIH Common Fund's National Metabolomics Data Repository (NMDR) website, the Metabolomics Workbench, https://www.metabolomicsworkbench.org where it has been assigned Study ID ST003211. The data can be accessed directly via its Project DOI: http://doi.org/10.21228/M8TR5T. Data for Figures 6 and 8 are included in Supplementary file 1.
Article and author information
Author details
David Louis Adelson
Funding
National Health and Medical Research Council (1144966)
- Maarten van den Buuse
- David K Gardner
- David Louis Adelson
- Patrick S Western
National Health and Medical Research Council (1144887)
- David K Gardner
- David Louis Adelson
- Patrick S Western
National Health and Medical Research Council (2021247)
- David Louis Adelson
- Patrick S Western
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Reviewing Editor
- Adèle L Marston, University of Edinburgh, United Kingdom
Ethics
Animal experimentation: All animal work was undertaken in accordance with Monash University Animal Ethics Committee (AEC) approvals issued by Monash University and Hudson Institute Animal Ethics Committees (AEC), approval numbers MMCB/2018/16 and MMCB/2020/37
Version history
- Received: July 14, 2022
- Preprint posted: August 11, 2022 (view preprint)
- Accepted: May 2, 2024
- Accepted Manuscript published: May 30, 2024 (version 1)
- Version of Record published: May 30, 2024 (version 2)
Copyright
© 2024, Oberin et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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Fetal growth delay caused by loss of non-canonical imprinting is resolved late in pregnancy and culminates in offspring overgrowth
eLife 13:e81875.
https://doi.org/10.7554/eLife.81875
Further reading
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