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Updated: May 29, 2026
06:44
Assessment of Global DNA Double-Strand End Resection using BrdU-DNA Labeling coupled with Cell Cycle Discrimination Imaging
Published on: April 28, 2021
Double-strand break end resection and repair pathway choice
Lorraine S Symington1, Jean Gautier
1Department of Microbiology & Immunology, Columbia University Medical Center, New York, New York 10032, USA. lss5@columbia.edu
Annual Review of Genetics
|September 14, 2011
Summary
DNA double-strand breaks (DSBs) are repaired by distinct pathways, including nonhomologous end joining (NHEJ) and homologous recombination (HR). DNA end resection critically influences this choice, directing repair towards HR and away from NHEJ.
Area of Science:
- Molecular Biology
- Genetics
- Cell Biology
Background:
- DNA double-strand breaks (DSBs) pose a significant threat to genomic stability, potentially leading to mutations or cell death.
- Two primary repair mechanisms exist: nonhomologous end joining (NHEJ) and homologous recombination (HR).
Purpose of the Study:
- To review the molecular machinery involved in DNA end resection.
- To elucidate the factors influencing DSB repair pathway choice, focusing on the role of resection.
Main Methods:
- Literature review of DNA repair pathways.
- Analysis of factors affecting DNA end processing.
Main Results:
- DNA end resection is a key event that directs DSB repair towards homologous recombination.
- The cell cycle phase and the nature of DSB ends influence the initiation and extent of resection.
- Cross-talk between end processing and NHEJ is crucial for appropriate repair.
Conclusions:
- Understanding DNA end resection is vital for comprehending DSB repair pathway selection.
- Factors like cell cycle and end structure modulate resection, impacting the balance between NHEJ and HR.
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