8-Oxo-deoxyadenosine (8-Oxo-dA) is classified as an oxidized nucleotide, and is primarily used in studies of oxidative DNA damage and associated repair mechanisms. In the cell, 8-Oxo-dA DNA lesions are formed by reaction with reactive oxygen species (ROS) generated either via normal oxidative metabolic processes, UV ionizing radiation, or 2-nitropropane (an industrial solvent and component of tobacco smoke) (1). 8-Oxo-dA can potentially mispair with G, but this potential is fairly limited (2). As a single-base lesion, 8-Oxo-dA is removed by the base excision repair (BER) mechanism and the native guanine base restored (3). In the cell, 8-Oxo-dA does not appear to be strongly mutagenic (4).
References
1. Feig, D.I., Sowers, L.C., Loeb, L.A. Reverse chemical mutagenesis: Identification of the mutagenic lesions resulting from reactive oxygen species-mediated damage to DNA. Proc. Natl. Acad. Sci. USA. (1994), 91: 6609-6613.
2. Shibutani, S., Bodepudi, V., Johnson, F., Grollman, A.P. Translesional Synthesis on DNA Templates Containing 8-Oxo-7,8-dihydrodeoxyadenosine. Biochem. (1993), 32: 4615-4621.
3. Nilsen, H., Krokan, H.E. Base excision repair in a network of defence and tolerance.Carcinogenesis (2001), 22: 987-998.
4. Kalam, M.A., Haraguchi, K., Chandani, S., Loechler, E.L., Moriya, M., Greenberg, M.M., Basu, A.K Genetic effects of oxidative DNA damages: comparative mutagenesis of the imidazole ring-opened formamidopyrimidines (Fapy lesions) and 8-oxo-purines in simian kidney cells. Nucleic Acids Res. (2006), 34: 2305-2315.
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