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Mutations induced by 2-hydroxy-dATP during in vitro replication with a HeLa extract.
Kazuya Satou1, Hideyoshi Harashima, Hiroyuki Kamiya
1Graduate School of Pharmaceutical Sciences, Hokkaido University, Kita-12, Nishi-6, Kita-ku, Sapporo 060-0812, Japan.
Nucleic Acids Research. Supplement (2001)
|September 27, 2003
Summary
Oxidized 2-hydroxydeoxyadenosine 5'-triphosphate (2-OH-dATP) causes DNA mutations, primarily G x C to A x T transitions. The MTH1 protein suppresses this mutagenicity in mammalian cells.
Area of Science:
- Molecular Biology
- Genetics
- Biochemistry
Background:
- Oxidative stress can damage DNA building blocks, potentially leading to mutations.
- 2-hydroxydeoxyadenosine 5 riphosphate (2-OH-dATP) is an oxidized form of dATP implicated in DNA damage.
- Understanding the mutagenic potential of 2-OH-dATP and its cellular repair mechanisms is crucial.
Purpose of the Study:
- To investigate the mutagenicity of 2-OH-dATP in a cellular replication system.
- To identify cellular factors that may mitigate the mutagenic effects of 2-OH-dATP.
Main Methods:
- Utilized an SV40 origin-dependent in vitro replication system.
- Employed a HeLa cell extract for the replication assay.
- Analyzed mutation types induced by 2-OH-dATP.
Main Results:
- 2-OH-dATP primarily induced G x C to A x T transitions.
- A lesser extent of G x C to T x A transversions was observed.
- Mutagenicity of 2-OH-dATP was increased by MTH1 inhibition, suggesting MTH1's role in 2-OH-dATP hydrolysis.
Conclusions:
- 2-OH-dATP is a mutagenic DNA lesion.
- The MTH1 protein plays a protective role by hydrolyzing 2-OH-dATP during replication in mammalian cells.
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