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Examining DNA Double-Strand Break Repair in a Cell Cycle-Dependent Manner
Janapriya Saha1, Shih-Ya Wang1, Anthony J Davis1
1University of Texas Southwestern Medical Center, Dallas, TX, United States.
Methods in Enzymology
|June 25, 2017
Summary
This study presents methods to measure DNA double-strand break (DSB) repair pathways, nonhomologous end joining (NHEJ) and homologous recombination (HR), across the cell cycle. These assays help understand how cells choose between these crucial genome stability mechanisms.
Area of Science:
- Molecular Biology
- Genetics
- Cell Biology
Background:
- DNA double-strand breaks (DSBs) are critical DNA lesions impacting genome stability.
- Both exogenous and endogenous factors induce daily DSBs in mammalian cells.
- Two primary repair pathways, nonhomologous end joining (NHEJ) and homologous recombination (HR), counteract DSBs.
Purpose of the Study:
- To describe assays for measuring DNA repair pathway contributions.
- To differentiate between NHEJ and HR activities.
- To analyze repair pathway usage across different cell cycle phases.
Main Methods:
- Development of assays to distinguish between NHEJ and HR.
- Application of methods to various mammalian cell lines.
- Monitoring of DNA repair pathway activity throughout the cell cycle.
Main Results:
- Established methods allow for the measurement of DSB repair pathway contributions.
- The assays can differentiate between NHEJ and HR.
- Cell cycle-dependent repair pathway usage can be monitored.
Conclusions:
- The described methods are simple and broadly applicable to mammalian cell lines.
- These assays provide a utility for studying cell cycle-dependent DNA double-strand break repair.
- Understanding DSB repair pathway choice is essential for maintaining genome stability.
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