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Analysis of Apoptosis in Zebrafish Embryos by Whole-mount Immunofluorescence to Detect Activated Caspase 3
Published on: December 20, 2013
Postmeiotic unfertilized starfish eggs die by apoptosis
1Department of Molecular Biology and Genetics, Bosphorus University, Bebek, 80815, Istanbul, Turkey.
Developmental Biology
|August 24, 2001
Summary
Unfertilized starfish eggs undergo apoptosis after a 16-20 hour arrest. This programmed cell death is protein synthesis-dependent and calcium-inhibited, offering a model for developmental apoptosis.
Area of Science:
- Developmental Biology
- Cell Biology
- Apoptosis Research
Background:
- Fertilization triggers rapid starfish egg development post-meiosis.
- Unfertilized eggs arrest in postmeiotic interphase before death.
- The mechanism of death in unfertilized eggs was previously unknown.
Purpose of the Study:
- To characterize the mechanism of death in unfertilized, postmeiotic starfish eggs.
- To investigate the molecular events and signaling pathways involved in egg death.
- To establish starfish eggs as a model for studying developmentally regulated apoptosis.
Main Methods:
- Observation of unfertilized starfish eggs over time.
- Analysis of cellular morphology and DNA fragmentation (TUNEL assay).
- Investigation of protein synthesis and intracellular calcium (Ca2+) levels.
Main Results:
- Unfertilized eggs arrest for 16-20 hours before synchronous death.
- Dying eggs exhibit apoptotic features: blebbing, contraction, fragmentation, and DNA fragmentation.
- Apoptosis requires protein synthesis and is inhibited by increased intracellular Ca2+.
Conclusions:
- Postmeiotic unfertilized starfish eggs undergo apoptosis.
- Starfish eggs provide a valuable model for studying the regulation of developmentally programmed cell death.
- Fertilization signaling, particularly Ca2+ influx, inhibits apoptosis in these cells.
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