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Updated: Jul 22, 2026
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Defining the Program of Maternal mRNA Translation during In vitro Maturation using a Single Oocyte Reporter Assay
Published on: June 16, 2021
Mechanisms underlying oocyte activation and postovulatory ageing
Rafael A Fissore1, Manabu Kurokawa, Jason Knott
1Department of Veterinary and Animal Sciences, University of Massachusetts, Amherst, MA 01003, USA. rfissore@vasci.umass.edu
Reproduction (Cambridge, England)
|January 18, 2003
Summary
Mammalian oocytes mature to optimize development post-fertilization. However, aging oocytes undergo fragmentation, suggesting a need to understand calcium signaling and cellular changes during oocyte aging.
Area of Science:
- Reproductive Biology
- Cellular Biology
- Developmental Biology
Background:
- Mammalian oocytes undergo maturation before ovulation to ensure successful fertilization and development.
- Sperm entry triggers calcium oscillations ([Ca(2+)](i)) crucial for oocyte activation and initiating development.
- Mature oocytes have transient optimizing changes that rapidly deteriorate, leading to aging-related fragmentation.
Purpose of the Study:
- To review mechanisms by which sperm initiate calcium oscillations in oocytes.
- To explore cellular and molecular changes causing postovulatory oocyte fragmentation in aging mammalian oocytes.
Main Methods:
- Literature review of oocyte maturation, fertilization, calcium signaling, and aging.
- Analysis of cellular and molecular events during oocyte aging and fragmentation.
Main Results:
- Spermatozoa initiate persistent [Ca(2+)](i) oscillations, triggering distinct developmental programs.
- Aging mammalian oocytes exhibit rapid deterioration of maturation-induced changes.
- Extended oocyte aging leads to fragmentation, programmed cell death, and abnormal development.
Conclusions:
- Understanding sperm-induced calcium signaling is key to oocyte activation.
- Investigating the mechanisms of oocyte aging and fragmentation is crucial for improving reproductive success and developmental outcomes.
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