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Updated: Jun 11, 2026
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Analysis of Chromosome Segregation, Histone Acetylation, and Spindle Morphology in Horse Oocytes
Published on: May 11, 2017
Effects of oocyte vitrification on histone modifications
Li-Ying Yan1, Jie Yan, Jie Qiao
1Center of Reproductive Medicine, Department of Obstetrics and Gynecology, Peking University Third Hospital, Beijing, China.
Reproduction, Fertility, and Development
|July 2, 2010
Summary
Oocyte vitrification affects key histone modifications, specifically increasing H3K9 methylation and H4K5 acetylation. These epigenetic changes highlight oocyte sensitivity and offer markers for optimizing cryopreservation.
Area of Science:
- Reproductive biology
- Epigenetics
- Cryobiology
Background:
- Vitrification is a common assisted reproductive technology.
- Its impact on oocyte survival and epigenetic modifications requires evaluation.
Purpose of the Study:
- To assess the survival of mouse MII oocytes post-vitrification.
- To investigate changes in specific histone modifications (H3K9, H4K5, H3K14) after vitrification.
Main Methods:
- Mouse MII oocytes were subjected to vitrification and warming.
- Histone modifications, including H3K9 dimethylation, H4K5 acetylation, and H3K14 acetylation, were analyzed.
Main Results:
- Oocyte survival rates were evaluated post-vitrification.
- Vitrification led to increased H3K9 methylation and H4K5 acetylation.
- H3K14 acetylation was undetectable in both non-vitrified and vitrified oocytes.
Conclusions:
- Oocytes exhibit sensitivity to vitrification-induced changes in H3K9 and H4K5 modifications.
- These histone modifications can serve as markers for epigenetic perturbations during cryopreservation.
- Monitoring these markers may aid in optimizing human oocyte cryopreservation protocols.
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