Repair of Oxidative Damage to Nuclear and Mitochondrial DNA in Mammalian Cells

Reactive oxygen species (ROS) 1The abbreviations used are: ROS, reactive oxygen species; BER, base excision repair; NER, nucleotide excision repair; AD, Alzheimer's disease; endo, endonuclease; TCR, transcription-coupled repair; 8-oxoG, 8-hydroxyguanine; 8-oxodG, 8-hydroxydeoxyguanine; TG, thymine glycol; AP, apurinic/apyrimidinc; GSR, gene-specific repair assay; XP, xeroderma pigmentosum; CS, Cockayne's syndrome; FapyG, 2,6-diamino-4hydroxyl-5-methylformamidopyrimidine. 1The abbreviations used are: ROS, reactive oxygen species; BER, base excision repair; NER, nucleotide excision repair; AD, Alzheimer's disease; endo, endonuclease; TCR, transcription-coupled repair; 8-oxoG, 8-hydroxyguanine; 8-oxodG, 8-hydroxydeoxyguanine; TG, thymine glycol; AP, apurinic/apyrimidinc; GSR, gene-specific repair assay; XP, xeroderma pigmentosum; CS, Cockayne's syndrome; FapyG, 2,6-diamino-4hydroxyl-5-methylformamidopyrimidine. are generated in cells as a by-product of cellular metabolism. ROS react with proteins, lipids, and DNA. DNA base modifications, abasic sites, deoxyribose damage, and single and double strand breaks are all induced following various forms of oxidative stress. This review will focus on DNA repair of oxidative lesions by base excision repair (BER) and nucleotide excision repair (NER). We will focus on the mammalian BER enzymes that have recently been cloned and characterized. 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BER, base excision repair; NER, nucleotide excision repair; AD, Alzheimer's disease; endo, endonuclease; TCR, transcription-coupled repair; 8-oxoG, 8-hydroxyguanine; 8-oxodG, 8-hydroxydeoxyguanine; TG, thymine glycol; AP, apurinic/apyrimidinc; GSR, gene-specific repair assay; XP, xeroderma pigmentosum; CS, Cockayne's syndrome; FapyG, 2,6-diamino-4hydroxyl-5-methylformamidopyrimidine. 1The abbreviations used are: ROS, reactive oxygen species; BER, base excision repair; NER, nucleotide excision repair; AD, Alzheimer's disease; endo, endonuclease; TCR, transcription-coupled repair; 8-oxoG, 8-hydroxyguanine; 8-oxodG, 8-hydroxydeoxyguanine; TG, thymine glycol; AP, apurinic/apyrimidinc; GSR, gene-specific repair assay; XP, xeroderma pigmentosum; CS, Cockayne's syndrome; FapyG, 2,6-diamino-4hydroxyl-5-methylformamidopyrimidine. are generated in cells as a by-product of cellular metabolism. ROS react with proteins, lipids, and DNA. DNA base modifications, abasic sites, deoxyribose damage, and single and double strand breaks are all induced following various forms of oxidative stress. This review will focus on DNA repair of oxidative lesions by base excision repair (BER) and nucleotide excision repair (NER). We will focus on the mammalian BER enzymes that have recently been cloned and characterized. 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