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10:24
Two- and Three-Dimensional Live Cell Imaging of DNA Damage Response Proteins
Published on: September 28, 2012
Rad51-deficient vertebrate cells accumulate chromosomal breaks prior to cell death
E Sonoda1, M S Sasaki, J M Buerstedde
1Bayer Chair, Department of Molecular Immunology and Allergology, Faculty of Medicine, Kyoto University, Japan.
The EMBO Journal
|February 28, 1998
Summary
Rad51 is essential for repairing DNA double-strand breaks in higher eukaryotes. Rad51- cells exhibit chromosome breaks and cell cycle arrest, confirming its vital role in proliferating cells.
Area of Science:
- Molecular Biology
- Genetics
- Cell Biology
Background:
- Yeast rad51 mutants are viable but sensitive to DNA damage, while murine RAD51 disruption is lethal, suggesting an essential role in vertebrates.
- RAD51 is crucial for DNA repair, particularly double-strand break repair, a process vital for maintaining genomic stability.
Purpose of the Study:
- To investigate the essential role of RAD51 in DNA double-strand break repair in higher eukaryotic proliferating cells.
- To characterize the cellular and chromosomal consequences of RAD51 deficiency in a chicken B lymphocyte model.
Main Methods:
- Generated chicken DT40 B lymphocyte clones with a repressible human RAD51 transgene.
- Disrupted endogenous RAD51 loci and inhibited transgene expression to create Rad51- cells.
- Analyzed cell cycle progression and chromosomal aberrations in Rad51- cells.
Main Results:
- Inhibition of RAD51 led to G2/M cell cycle arrest and cell death.
- Rad51- cells displayed a high frequency of isochromatid-type chromosome breaks.
- These findings highlight the critical role of RAD51 in maintaining chromosomal integrity.
Conclusions:
- RAD51 is essential for the repair of spontaneously occurring chromosome breaks in proliferating cells of higher eukaryotes.
- Deficiency in RAD51 results in genomic instability and cell death, underscoring its importance in cancer prevention and therapy.
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