Related Experiment Video
Updated: May 4, 2026

Visualizing and Quantifying Endonuclease-Based Site-Specific DNA Damage
Published on: August 21, 2021
Structure-specific endonucleases: guardians of fragile site stability
Sheroy Minocherhomji1, Ian D Hickson1
1Nordea Center for Healthy Aging, Department of Cellular and Molecular Medicine, University of Copenhagen, Denmark.
Abstract:
Fragile sites are conserved loci predisposed to form breaks in metaphase chromosomes. The inherent instability of these loci is associated with chromosomal rearrangements in cancers and is a feature of cells from patients with chromosomal instability syndromes. One class of fragile sites, the common fragile sites (CFSs), have previously been shown to recruit several DNA repair proteins after the completion of bulk DNA synthesis in the cell, probably indicative of their inability to complete timely DNA replication. CFS loci are also prone to trigger mitotic non-disjunction of sister chromatids, leading to the formation of ultra-fine anaphase bridges (UFBs) and micronuclei. We discuss recent developments in the CFS field; in particular, the role of DNA structure-specific endonucleases in promoting cleavage at CFSs.
Related Concept Videos
Restriction Enzymes
The host bacteria protect their own genomic DNA from these enzymes by methylating these sites. Some...
Homologous Recombination
Nucleotide Excision Repair
Nucleotide Excision Repair
Cells are regularly exposed to mutagens—factors in the environment that can damage DNA and generate mutations. UV radiation is one of the most common mutagens and is estimated to introduce a significant number of changes in DNA. These include bends or kinks in the structure, which can block DNA replication or transcription. If these errors are not fixed, the damage can cause mutations, which in turn can result in cancer or disease depending on which sequences are...
Nucleotide Excision Repair
Conservative Site-specific Recombination and Phase Variation
The recognition sites for Cre recombinase called LoxP...

