Related Experiment Video
Updated: Aug 10, 2026
08:18
Application of Laser Micro-irradiation for Examination of Single and Double Strand Break Repair in Mammalian Cells
Published on: September 5, 2017
XRCC1 and DNA strand break repair
1Genome Damage and Stability Centre, University of Sussex, Science Park Road, BN1 9RQ, Falmer Brighton, UK. k.w.caldecott@sussex.ac.uk
DNA Repair
|September 12, 2003
Summary
DNA single-strand breaks threaten genetic integrity but are repaired by XRCC1 protein. This review details XRCC1
Area of Science:
- Molecular Biology
- Genetics
- Biochemistry
Background:
- DNA single-strand breaks (SSBs) are critical lesions.
- SSBs arise from endogenous reactive oxygen species and direct deoxyribose damage.
- These lesions pose a constant threat to genomic stability.
Purpose of the Study:
- To review the protein-protein interactions mediated by XRCC1.
- To elucidate the role of XRCC1 in DNA repair pathways.
- To present models for SSB repair mechanisms.
Main Methods:
- Literature review of protein-protein interactions.
- Analysis of XRCC1's role in DNA repair.
- Development of mechanistic models for SSB repair.
Main Results:
- XRCC1 facilitates SSB repair by interacting with multiple repair enzymes.
- These interactions are crucial for both base excision repair and direct break repair.
- Specific models illustrating these repair processes are presented.
Conclusions:
- XRCC1 is a key scaffold protein in mammalian SSB repair.
- Understanding XRCC1 interactions provides insight into maintaining genetic integrity.
- The presented models enhance comprehension of DNA repair pathways.
Related Concept Videos
01:08Nucleotide Excision Repair
Overview
02:04Fixing Double-strand Breaks
The double-stranded structure of DNA has two major advantages. First, it serves as a safe repository of genetic information where one strand serves as the back-up in case the other strand is damaged. Second, the double-helical structure can be wrapped around proteins called histones to form nucleosomes, which can then be tightly wound to form chromosomes. This way, DNA chains up to 2 inches long can be contained within microscopic structures in a cell. A double-stranded break not only damages...
02:31Homologous Recombination
The basic reaction of homologous recombination (HR) involves two chromatids that contain DNA sequences sharing a significant stretch of identity. One of these sequences uses a strand from another as a template to synthesize DNA in an enzyme-catalyzed reaction. The final product is a novel amalgamation of the two substrates. To ensure an accurate recombination of sequences, HR is restricted to the S and G2 phases of the cell cycle. At these stages, the DNA has been replicated already and the...
02:37Restarting Stalled Replication Forks
DNA replication is initiated at sites containing predefined DNA sequences known as origins of replication. DNA is unwound at these sites by the minichromosome maintenance (MCM) helicase and other factors such as Cdc45 and the associated GINS complex.The unwound single strands are protected by replication protein A (RPA) until DNA polymerase starts synthesizing DNA at the 5’ end of the strand in the same direction as the replication fork. To prevent the replication fork from falling apart, a...
02:04Fixing Double-strand Breaks
The double-stranded structure of DNA has two major advantages. First, it serves as a safe repository of genetic information where one strand serves as the back-up in case the other strand is damaged. Second, the double-helical structure can be wrapped around proteins called histones to form nucleosomes, which can then be tightly wound to form chromosomes. This way, DNA chains up to 2 inches long can be contained within microscopic structures in a cell. A double-stranded break not only damages...
02:31Homologous Recombination
The basic reaction of homologous recombination (HR) involves two chromatids that contain DNA sequences sharing a significant stretch of identity. One of these sequences uses a strand from another as a template to synthesize DNA in an enzyme-catalyzed reaction. The final product is a novel amalgamation of the two substrates. To ensure an accurate recombination of sequences, HR is restricted to the S and G2 phases of the cell cycle. At these stages, the DNA has been replicated already and the...