title: Induction of the human oxidized base-specific DNA glycosylase NEIL1 by reactive oxygen species.
abstract: NEIL1, a mammalian DNA glycosylase and ortholog of Escherichia coli Nei/Fpg, is involved in the repair of oxidatively damaged bases in mammalian cells. Exposure of HCT116 human colon carcinoma cells to reactive oxygen species, generated by glucose oxidase (GO), enhanced the levels of NEIL1 mRNA and polypeptide by 2-4-fold by 6 h after GO treatment. A similar oxidative stress-induced increase in human NEIL1 (hNEIL1) promoter-dependent luciferase expression in HCT116 cells indicates that reactive oxygen species activates NEIL1 transcription. The transcriptional start site of hNEIL1 was mapped, and the upstream promoter sequence was characterized via luciferase reporter assay. Two identical CRE/AP-1-binding sites were identified in the promoter that binds transcription factors c-Jun and CREB/ATF2. This binding was significantly enhanced in extracts of cells treated with GO. Furthermore, a simultaneous increase in the level of phosphorylated c-Jun suggests its involvement in up-regulating the NEIL1 promoter. Oxidative stress-induced activation of NEIL1 appears to be involved in the feedback regulation of cellular repair activity needed to handle an increase in the level of oxidative base damage.
authors.affiliation: Sealy Center for Molecular Science and Department of Human Biological Chemistry and Genetics, University of Texas Medical Branch, Galveston 77555, USA.
authors.forename: Aditi
authors.initials: A
authors.lastname: Das
authors.forename: Tapas K
authors.initials: TK
authors.lastname: Hazra
authors.forename: Istvan
authors.initials: I
authors.lastname: Boldogh
authors.forename: Sankar
authors.initials: S
authors.lastname: Mitra
authors.forename: Kishor K
authors.initials: KK
authors.lastname: Bhakat
mesh_terms: D001483:Base Sequence; D001665:Binding Sites; D015153:Blotting, Western; D045744:Cell Line, Tumor; D003001:Cloning, Molecular; D017362:Cyclic AMP Response Element-Binding Protein / Q000378:metabolism; D045647:DNA Glycosylases / Q000737:chemistry* / Q000502:physiology; D017931:DNA Primers / Q000737:chemistry; D006801:Humans; D008156:Luciferases / Q000378:metabolism; D008969:Molecular Sequence Data; D018384:Oxidative Stress; D010100:Oxygen / Q000378:metabolism*; D010766:Phosphorylation; D010957:Plasmids / Q000378:metabolism; D011401:Promoter Regions, Genetic; D011485:Protein Binding; D016755:Proto-Oncogene Proteins c-jun / Q000378:metabolism; D017382:Reactive Oxygen Species; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013997:Time Factors; D014158:Transcription, Genetic; D015533:Transcriptional Activation; D014162:Transfection; D015854:Up-Regulation
chemical_list: D017362:Cyclic AMP Response Element-Binding Protein; D017931:DNA Primers; D016755:Proto-Oncogene Proteins c-jun; D017382:Reactive Oxygen Species; D008156:Luciferases; D045647:DNA Glycosylases; C473634:NEIL1 protein, human; D010100:Oxygen