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Mutations induced by reactive nitrogen oxide species in the supF forward mutation assay
1Department of Biological Sciences, De Montfort University, The Hawthorn Building, The Gateway, LE1 9BH, Leicester, UK. mnr1@le.ac.uk
Mutation Research
|June 6, 2000
Summary
Reactive nitrogen oxides, including nitric oxide, can damage DNA and cause mutations. This review examines the mutagenicity of various reactive nitrogen species and their DNA lesions, comparing findings from the supF assay in human and E. coli cells.
Area of Science:
- Biochemistry
- Molecular Biology
- Genetics
Background:
- Nitric oxide (NO) is a crucial bioregulatory molecule.
- NO can react with oxygen species to form reactive nitrogen oxides (RNOS).
- RNOS can cause DNA damage, leading to mutations.
Purpose of the Study:
- To review the mutagenicity of various RNOS and DNA damaging agents.
- To analyze the DNA lesions responsible for induced mutations.
- To compare mutations induced by NO and other agents in the supF assay.
Main Methods:
- Utilizing the supF forward mutation assay.
- Investigating DNA lesions caused by NO, N(2)O(3), nitrous acid, peroxynitrite, and reactive oxygen species.
- Comparing mutation profiles in human and Escherichia coli cells after plasmid replication.
Main Results:
- RNOS induce mutations through specific DNA base sequence alterations.
- The nature of DNA lesions varies depending on the specific RNOS.
- Replication in different cellular systems (human vs. E. coli) can influence mutation outcomes.
Conclusions:
- RNOS are significant mutagens capable of inducing diverse DNA lesions.
- Understanding these lesions is key to comprehending NO-mediated genotoxicity.
- Cellular replication context impacts the mutagenic potential of RNOS-induced DNA damage.
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