title: Accelerated repair and reduced mutagenicity of oxidative DNA damage in human bladder cells expressing the E. coli FPG protein.
abstract: Repair of some oxidized purines such as 8-oxo-7,8-dihydroguanine (8-oxoG) is inefficient in human cells in comparison to repair of other major endogenous lesions (e.g. uracil, abasic sites or oxidized pyrimidines). This is due to the poor catalytic properties of hOGG1, the major DNA glycosylase involved in 8-oxoG removal. The formamidopyrimidine DNA glycosylase (FPG) protein from E. coli is endowed with a potent 8-oxoG glycolytic activity coupled with a beta,delta-AP lyase. In this study, we have expressed FPG fused to the enhanced green fluorescent protein (EGFP) in human bladder cells to accelerate the repair of oxidative DNA damage. Cells expressing the fusion protein EGFP-FPG repaired 8-oxoG and AP sites at accelerated rates, in particular via the single-nucleotide insertion base excision repair (BER) pathway and were resistant to mutagenicity of the oxidizing carcinogen potassium bromate. FPG may stably protect human cells from some harmful effects of oxidative DNA damage.
authors.affiliation: Department of Translational Oncology, Experimental Oncology B Laboratory, Istituto Nazionale Ricerca Cancro, Largo Rosanna Benzi n. 10, 16132 Genova, Italy.
authors.forename: Monica
authors.initials: M
authors.lastname: Ropolo
authors.forename: Alessandro
authors.initials: A
authors.lastname: Geroldi
authors.forename: Paolo
authors.initials: P
authors.lastname: Degan
authors.forename: Virginia
authors.initials: V
authors.lastname: Andreotti
authors.forename: Simona
authors.initials: S
authors.lastname: Zupo
authors.forename: Alessandro
authors.initials: A
authors.lastname: Poggi
authors.forename: April
authors.initials: A
authors.lastname: Reed
authors.forename: Mark R
authors.initials: MR
authors.lastname: Kelley
authors.forename: Guido
authors.initials: G
authors.lastname: Frosina
mesh_terms: D001959:Bromates / Q000633:toxicity; D002273:Carcinogens / Q000633:toxicity; D018929:Cell Culture Techniques; D004249:DNA Damage; D004260:DNA Repair; D043382:DNA-Formamidopyrimidine Glycosylase / Q000378:metabolism*; D029968:Escherichia coli Proteins / Q000378:metabolism*; D005347:Fibroblasts; D049452:Green Fluorescent Proteins; D006147:Guanine / Q000031:analogs & derivatives / Q000633:toxicity; D006801:Humans; D018384:Oxidative Stress; D017382:Reactive Oxygen Species; D001743:Urinary Bladder / Q000166:cytology*; D001749:Urinary Bladder Neoplasms / Q000503:physiopathology
chemical_list: D001959:Bromates; D002273:Carcinogens; D029968:Escherichia coli Proteins; D017382:Reactive Oxygen Species; C019536:potassium bromate; D049452:Green Fluorescent Proteins; C024829:8-hydroxyguanine; D006147:Guanine; D043382:DNA-Formamidopyrimidine Glycosylase; C468610:DNA-formamidopyrimidine glycosylase, E coli