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Updated: Jun 26, 2026
08:00
Defining the Program of Maternal mRNA Translation during In vitro Maturation using a Single Oocyte Reporter Assay
Published on: June 16, 2021
An Overview of How Epigenetics, MicroRNA-21, and Endocrine Disrupting Compounds Affect Oocyte Maturation and
Monique Nasser1, Reem Sabry1, Laura A Favetta1
1Reproductive Health and Biotechnology Laboratory, Department of Biomedical Sciences, Ontario Veterinary College, University of Guelph, Guelph, ON N1G 2W1, Canada.
Journal of Developmental Biology
|June 25, 2026
Summary
Epigenetic factors like microRNA-21 are crucial for egg cell maturation and early embryo development. Environmental factors can disrupt these epigenetic processes, impacting reproductive health and development.
Area of Science:
- Reproductive biology and developmental science.
- Molecular and cellular biology.
- Environmental toxicology.
Background:
- Epigenetic regulation, including DNA methylation, histone modifications, and non-coding RNAs, is essential for reproductive processes.
- MicroRNA-21 (miR-21) plays a key role in oocyte maturation, apoptosis, and cumulus cell function, influencing oocyte competency.
- Dysregulation of miR-21 can result in impaired oocyte maturation and embryonic development, leading to developmental abnormalities.
Purpose of the Study:
- To review the intricate relationship between epigenetic mechanisms, microRNA regulation, and environmental influences on oocyte maturation and pre-implantation embryonic development.
- To highlight the significance of miR-21 in reproductive processes and the potential impact of its dysregulation.
- To underscore the role of epigenetic modifications in cellular reprogramming during early embryonic development.
Main Methods:
- Literature review focusing on epigenetic mechanisms (DNA methylation, histone modifications, non-coding RNAs) in reproduction.
- Analysis of the role of microRNA-21 in oocyte maturation and embryonic development.
- Examination of the impact of environmental factors, such as endocrine disruptors, on epigenetic regulation and reproductive outcomes.
Main Results:
- Epigenetic regulation is fundamental for successful oocyte maturation and pre-implantation development.
- miR-21 is a critical regulator of meiotic progression and oocyte competency; its dysregulation is linked to developmental defects.
- Environmental factors, particularly endocrine disruptors, can alter miR-21 expression, potentially disrupting reproductive health and developmental programming.
Conclusions:
- Epigenetics, miRNA regulation, and environmental factors are interconnected and critically influence oocyte maturation and early embryonic development.
- Understanding these interactions is vital for addressing reproductive health issues and developmental disorders.
- Further mechanistic and translational research in reproductive epigenetics is warranted to elucidate these complex pathways.
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