Related Experiment Video
Updated: Feb 6, 2026
Analysis of DNA Double-strand Break DSB Repair in Mammalian Cells
Published on: September 8, 2010
Single-Strand Break End Resection in Genome Integrity: Mechanism and Regulation by APE2
Md Akram Hossain1, Yunfeng Lin2, Shan Yan3
1Department of Biological Sciences, University of North Carolina at Charlotte, Charlotte, NC 28223, USA. mhossai5@uncc.edu.
Abstract:
DNA single-strand breaks (SSBs) occur more than 10,000 times per mammalian cell each day, representing the most common type of DNA damage. Unrepaired SSBs compromise DNA replication and transcription programs, leading to genome instability. Unrepaired SSBs are associated with diseases such as cancer and neurodegenerative disorders. Although canonical SSB repair pathway is activated to repair most SSBs, it remains unclear whether and how unrepaired SSBs are sensed and signaled. In this review, we propose a new concept of SSB end resection for genome integrity. We propose a four-step mechanism of SSB end resection: SSB end sensing and processing, as well as initiation, continuation, and termination of SSB end resection. We also compare different mechanisms of SSB end resection and DSB end resection in DNA repair and DNA damage response (DDR) pathways. We further discuss how SSB end resection contributes to SSB signaling and repair. We focus on the mechanism and regulation by APE2 in SSB end resection in genome integrity. Finally, we identify areas of future study that may help us gain further mechanistic insight into the process of SSB end resection. Overall, this review provides the first comprehensive perspective on SSB end resection in genome integrity.
Insights
DNA single-strand breaks (SSBs) are common. This review introduces SSB end resection, a new mechanism for sensing and repairing these breaks, crucial for maintaining genome integrity and preventing disease.
Area of Science:
- Molecular Biology
- Genetics
- Cell Biology
Background:
- DNA single-strand breaks (SSBs) are the most frequent DNA damage, occurring over 10,000 times daily in mammalian cells.
- Unrepaired SSBs can lead to genome instability, impacting DNA replication and transcription, and are linked to diseases like cancer and neurodegenerative disorders.
- The sensing and signaling mechanisms for unrepaired SSBs remain incompletely understood, despite the activation of canonical SSB repair pathways.
Purpose of the Study:
- To propose and detail a novel concept of SSB end resection as a critical process for maintaining genome integrity.
- To elucidate a proposed four-step mechanism of SSB end resection: sensing/processing and initiation/continuation/termination.
- To compare SSB end resection with double-strand break (DSB) end resection within DNA repair and DNA damage response (DDR) pathways.
Main Methods:
- Review and synthesis of existing literature on DNA repair and damage response pathways.
- Comparative analysis of SSB end resection and DSB end resection mechanisms.
- Focus on the role and regulation of APE2 in SSB end resection.
Main Results:
- Proposal of a novel four-step mechanism for SSB end resection.
- Comparison highlighting similarities and differences between SSB and DSB end resection.
- Discussion on the contribution of SSB end resection to SSB signaling and repair.
Conclusions:
- SSB end resection is a key process for maintaining genome integrity.
- APE2 plays a significant role in the mechanism and regulation of SSB end resection.
- Further research is needed to fully understand the mechanistic insights into SSB end resection.
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