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Published on: November 1, 2011
Hypersensitivity to DNA damage leads to increased apoptosis during early mouse development
B S Heyer1, A MacAuley, O Behrendtsen
1Department of Anatomy, University of California, San Francisco, San Francisco, California 94143-0452 USA. Babette@itsa.ucsf.edu
Genes & Development
|August 19, 2000
Summary
Early mouse embryos undergoing gastrulation eliminate cells damaged by radiation through apoptosis. This novel surveillance mechanism ensures genomic integrity during rapid development.
Area of Science:
- Developmental biology
- Genomics
- Cellular stress response
Background:
- Gastrulation in mice involves rapid cell proliferation and differentiation.
- High proliferation rates can lead to increased production of damaged cells.
- Embryonic development requires mechanisms to maintain genomic integrity.
Purpose of the Study:
- To investigate a novel surveillance mechanism for eliminating radiation-damaged cells during mouse gastrulation.
- To understand the embryo's response to genotoxic stress during a critical developmental window.
Main Methods:
- Exposing mouse embryos to low-dose ionizing radiation (<0.5 Gy) during gastrulation.
- Observing cellular responses, including apoptosis and cell cycle arrest.
- Analyzing the involvement of Atm and p53 pathways in the apoptotic response.
Main Results:
- Mouse embryos exhibit hypersensitivity to DNA damage during gastrulation.
- Irradiated embryonic cells, including germ cell progenitors, undergo apoptosis without cell cycle arrest.
- This hypersensitivity is dependent on Atm and p53 pathways.
- Extraembryonic cells do not exhibit this hypersensitivity.
Conclusions:
- A novel, cell fate-dependent apoptosis mechanism eliminates DNA-damaged cells during mouse gastrulation.
- This mechanism ensures genomic integrity in embryonic cells, particularly germ cell progenitors, during rapid proliferation and differentiation.
- The findings highlight a critical quality control process in early mammalian development.
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