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Updated: Aug 9, 2026

Advanced Confocal Microscopy Techniques to Study Protein-protein Interactions and Kinetics at DNA Lesions
Published on: November 12, 2017
Formation and processing of UV photoproducts: effects of DNA sequence and chromatin environment
1Department of Biology, Beckman Institute of the City of Hope, Duarte, CA 91010, USA. gpfeifer@smtplink.coh.org
Abstract:
Cyclobutane pyrimidine dimers and (6-4) photoproducts are the two major classes of lesions produced in DNA by UVB and UVC irradiation. Their distribution along genes is nucleotide sequence-dependent. In vivo, the frequency of these lesions at specific sites is modulated by nucleosomes and other DNA binding proteins. Repair of UV photoproducts is dependent on the transcriptional status of the sequences to be repaired and on the chromatin environment. The formation of DNA photolesions by UV light is responsible for the induction of mutations and the development of skin cancer. To understand the mechanisms of UV mutagenesis, it is important to know how these lesions are formed, by which cellular pathways they are repaired and how they are dealt with by DNA polymerases.
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