# Dnmt3b activities in mouse development

> **NIH NIH R01** · UNIVERSITY OF FLORIDA · 2024 · $58,098

## Abstract

PROJECT SUMMARY
Project title: Dnmt3b activities in mouse development
DNA methylation is an epigenetic modification involved in the transcriptional regulation of genes
involved in development and differentiation, and its deregulation contributes to human
pathogenesis. It is catalyzed by the family of DNA methyltransferases including catalytically
active Dnmt1, Dnmt3a, and Dnmt3b. DNA methylation plays a major role in preimplantation
development in mice. To establish a new epigenome, the mouse zygotic genome undergoes
epigenetic reprogramming, including global DNA demethylation at the 8-cell stage. Upon
implantation, a wave of de novo methylation in epiblast cells mediated by de novo enzymes
Dnmt3a and Dnmt3b results in new methylation patterns maintained by Dnmt1 that form a basis
for tissue-specific expression and differentiation. Dnmt3b regulates developmental and
imprinted genes, X chromosome inactivation, pericentromeric regions, gene bodies, and other
genomic regions. Its importance in mouse development was demonstrated by the embryonic
lethality of Dnmt3b-/- mice. We recently found that Dnmt3bCI/CI mice expressing catalytically
inactive Dnmt3bCI protein survived both pre-and postnatal development. Molecular analysis
suggested that the accessory function - the ability to recruit other Dnmts to proper genomic loci
– of Dnmt3b rather than its catalytic activity, is important for methylation and survival. Here we
hypothesize that Dnmt3b is a multifaceted protein whose various activities affect pre-and
postnatal development and disease formation in mice. In Aim 1, we analyze global methylation
and expression at different stages of development in mice lacking various Dnmt activities to
determine the scope of Dnmt3b’s accessory function in Dnmt3a-mediated de novo methylation
in vivo. In Aim 2, will test the ability of Dnmt3b to complex with other Dnmts and contribute to de
novo methylation induced by other Dnmts in Dnmt1-/-;Dnmt3a-/-;Dnmt3b-/- mouse embryonic
stem cells. In addition, we will test the importance of Dnmt3a and Dnmt3l for Dnmt3b’s
accessory function and validate our data in a human cell line. In Aim 3, we will assess disease
development in mice conceived through the use of in vitro fertilization techniques to analyze
disease development, Dnmt levels, the rate of methylation and gene expression errors, as well
as their persistence over time. Collectively, our studies will reveal the physiological relevance of
Dnmt3b activities in mouse development, and uncover basic mechanisms utilizing Dnmt3b
functions and their involvement in IVF. Our results could result in a changed focus of preventive
care for individuals conceived by Assisted Reproductive Technologies.

## Key facts

- **NIH application ID:** 10913857
- **Project number:** 3R01GM145745-03S1
- **Recipient organization:** UNIVERSITY OF FLORIDA
- **Principal Investigator:** Rene Opavsky
- **Activity code:** R01 (R01, R21, SBIR, etc.)
- **Funding institute:** NIH
- **Fiscal year:** 2024
- **Award amount:** $58,098
- **Award type:** 3
- **Project period:** 2022-06-01 → 2026-04-30

## Primary source

NIH RePORTER: https://reporter.nih.gov/project-details/10913857

## Citation

> US National Institutes of Health, RePORTER application 10913857, Dnmt3b activities in mouse development (3R01GM145745-03S1). Retrieved via AI Analytics 2026-05-25 from https://api.ai-analytics.org/grant/nih/10913857. Licensed CC0.

---

*[NIH grants dataset](/datasets/nih-grants) · CC0 1.0*