Effect of hyperoxidized guanine on DNA primer-template structures: spiroiminodihydantoin leads to strand slippage.
Oxidation of guanine in DNA can lead to mutagenic lesions such as 7-hydro-8-oxoguanine (oG). Upon further oxidation, a more mutagenic lesion, spirominodihydantoin (Sp), can occur. In this study, nuclear magnetic resonance (NMR) investigations were performed to determine the structural features of DNA primer-template models with 5'-GG, 5'-G(oG), 5'-G(Sp) and 5'-T(Sp) templates, that mimic the situation in which the downstream G of the template has been oxidized to oG or hyperoxidized to Sp. Our results show that misalignment occurs only in the 5'-G(Sp) and 5'-T(Sp) templates, providing structural insights into the observed differences in mutagenicity of Sp and oG during DNA replication.
Fenn
Dickson
D
Department of Chemistry, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong.
Chi
Lai Man
LM
Lam
Sik Lok
SL
D001483:Base Sequence; D017931:DNA Primers / Q000737:chemistry*; D004261:DNA Replication; D006151:Guanosine / Q000031:analogs & derivatives* / Q000737:chemistry; D008956:Models, Chemical; D015394:Molecular Structure; D016296:Mutagenesis; D019906:Nuclear Magnetic Resonance, Biomolecular; D010084:Oxidation-Reduction; D010087:Oxides / Q000737:chemistry*; D013141:Spiro Compounds / Q000737:chemistry*; D013698:Templates, Genetic; D013816:Thermodynamics
D017931:DNA Primers; D010087:Oxides; D013141:Spiro Compounds; C408822:spiroiminodihydantoin; D006151:Guanosine