NEIL1 binding to DNA containing 2'-fluorothymidine glycol stereoisomers and the effect of editing.
Thymine glycol (Tg), one of the oxidized bases formed in DNA by reactive oxygen species, is repaired by the DNA glycosylases such as NEIL1, NTH1 and Endo III. In our recent studies, we showed that NEIL1's catalytic efficiency and lesion specificity are regulated by an RNA-editing adenosine deamination reaction. In this study, we synthesized oligodeoxynucleotides containing 2'-fluorothymidine glycol with either ribo or arabino configuration and investigated the binding of these modified DNAs with the unedited and edited forms of human NEIL1 along with E. coli Endo III. For the two forms of hNEIL1, binding affinities to FTg-containing DNA were similar indicating that the editing effect is more subtle than to simply alter substrate affinity. While the NEIL1-binding to FTg-containing DNAs was largely insensitive to C5 and 2' stereochemistry, a preference was observed for the FTg-G pair over the FTg-A pair. In addition, we found that optimal binding is observed with Endo III and duplex DNA with riboFTg(5S) paired with dG. The modified DNAs reported here will provide useful tools for further characterizing the interaction between DNA repair glycosylases and thymine glycol containing DNA.
Department of Chemistry, University of California, Davis, One Shields Avenue, Davis, CA 95616, USA.
Kazumitsu
K
Onizuka
Jongchan
J
Yeo
Sheila S
SS
David
Peter A
PA
Beal
D004247:DNA / Q000737:chemistry* / Q000378:metabolism*; D045647:DNA Glycosylases / Q000378:metabolism*; D043224:Deoxyribonuclease (Pyrimidine Dimer) / Q000378:metabolism; D029968:Escherichia coli Proteins / Q000378:metabolism; D006801:Humans; D009838:Oligodeoxyribonucleotides / Q000138:chemical synthesis / Q000737:chemistry / Q000378:metabolism; D009943:Organophosphorus Compounds / Q000138:chemical synthesis / Q000737:chemistry; D011485:Protein Binding; D017393:RNA Editing; D013237:Stereoisomerism; D013936:Thymidine / Q000031:analogs & derivatives* / Q000737:chemistry
C509335:1-(2-deoxy-2-fluororibofuranosyl)-5,6-dihydro-5,6-dihydroxythymine; D029968:Escherichia coli Proteins; D009838:Oligodeoxyribonucleotides; D009943:Organophosphorus Compounds; C434331:phosphoramidite; D004247:DNA; D043224:Deoxyribonuclease (Pyrimidine Dimer); C106403:NTH protein, E coli; D045647:DNA Glycosylases; C473634:NEIL1 protein, human; D013936:Thymidine