Work

On the irrelevancy of hydroxyl radical to DNA damage from oxidative stress and implications for epigenetics

Year: 2020

Type: review

Abstract: Contrary to frequent reports in the literature, hydroxyl radical is not a key species participating in endogenous oxidative DNA damage. Instead, carbonate radical anion is formed from the Fenton reaction under cellular conditions and from decomposition of nitrosoperoxycarbonate generated during inflammation. Carbonate radical anion is a potent one-electron oxidant capable of generating base radical cations that can migrate over long distances in duplex DNA, ultimately generating 8-oxo-7,8-dihydroguanine at a redox-sensitive sequence such as GGG. Such a mechanism enables G-quadruplex-forming sequences to act as long-range sensors of oxidative stress, impacting gene expression via the DNA repair mechanism that reads and ultimately erases the oxidized base. With a writing, reading and erasing mechanism in place, oxidative 'damage' to DNA might be relabeled as 'epigenetic' modifications.

Source: Chemical Society Reviews

DOI: 10.1039/d0cs00579g

Authors: Aaron M. Fleming, Cynthia J. Burrows

Institution: University of Utah

Language: English

Topic: DNA and Nucleic Acid Chemistry

Subfield: Molecular Biology

Field: Biochemistry, Genetics and Molecular Biology

Domain: Life Sciences

Open Access status: green

Funder: National Cancer Institute

Award: Chemistry and Biology of Oxidized Purine Lesions in DNA