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Updated: Jun 28, 2026
10:59
Visualizing and Quantifying Endonuclease-Based Site-Specific DNA Damage
Published on: August 21, 2021
DNA double-strand break processing: the beginning of the end
Steven Raynard1, Hengyao Niu, Patrick Sung
1Department of Molecular Biophysics and Biochemistry, Yale University School of Medicine, New Haven, Connecticut 06520, USA.
Genes & Development
|November 5, 2008
Summary
DNA double-strand breaks (DSBs) are processed by nucleolytic enzymes to create 3' single-stranded DNA (ssDNA) tails. These tails are crucial for DNA damage signaling and repair complex assembly, involving multiple nucleases.
Area of Science:
- Molecular Biology
- Genetics
- Biochemistry
Background:
- DNA double-strand breaks (DSBs) trigger cellular responses for genome stability.
- Nucleolytic processing of DSBs generates 3' single-stranded DNA (ssDNA) tails.
- These ssDNA tails are critical for recruiting DNA damage checkpoint and repair proteins.
Discussion:
- Multiple nucleases participate in the intricate process of DSB end resection.
- Recent genetic studies are elucidating the specific roles of these nucleases.
- Understanding DSB resection is key to comprehending DNA repair pathways.
Key Insights:
- The generation of 3' ssDNA tails is a fundamental step in DSB repair.
- DSB end resection involves a complex interplay of enzymatic activities.
- New research is beginning to map the nucleases involved in this pathway.
Outlook:
- Further investigation into the nucleases responsible for DSB resection is warranted.
- Elucidating this process will enhance our understanding of genome maintenance.
- This knowledge could have implications for cancer therapy and aging research.
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