Miscoding during DNA synthesis on damaged DNA templates catalysed by mammalian cell extracts

Cancer Lett. 1994 Aug 15;83(1-2):315-22. doi: 10.1016/0304-3835(94)90335-2.

Abstract

Oligodeoxynucleotides, modified site-specifically with 7,8-dihydro-8-oxodeoxyguanosine (8-oxodG), 7,8-dihydro-8-oxoadenosine (8-oxodA) and 6-O-methyldeoxyguanosine (O6medG), were used as templates for DNA synthesis in primer-extension reactions catalysed by extracts prepared from human (HeLa) cells, simian kidney (COS-7) cells and various mouse tissues. Fully-extended reaction products were analysed by two-phase polyacrylamide gel electrophoresis (Shibutani, Chem. Res. Toxicol. 6, 625, 1993). Using extracts prepared from HeLa or COS-7 cells, dAMP was preferentially incorporated opposite 8-oxodG; dTMP was incorporated opposite 8-oxodA and dTMP, accompanied by small amounts of dCMP, was incorporated opposite O6medG. Translesional synthesis was strongly inhibited by N-ethylmaleimide and partially inhibited by N-butylphenyl-dGTP. This model system can be used to predict the mutagenic potential of selectively-damaged DNA in mammalian cells.

MeSH terms

  • Animals
  • Base Sequence
  • Chlorocebus aethiops
  • DNA / biosynthesis*
  • DNA Damage*
  • DNA Polymerase II / antagonists & inhibitors
  • DNA Replication*
  • Deoxyguanine Nucleotides / pharmacology
  • Ethylmaleimide / pharmacology
  • Female
  • HeLa Cells
  • Humans
  • In Vitro Techniques
  • Mice
  • Mice, Inbred C57BL
  • Mice, Inbred DBA
  • Molecular Sequence Data
  • Mutagenesis
  • Oligodeoxyribonucleotides / chemistry
  • Templates, Genetic

Substances

  • Deoxyguanine Nucleotides
  • Oligodeoxyribonucleotides
  • N(2)-(4-n-butylphenyl)-2'-deoxyguanosine 5'-triphosphate
  • DNA
  • DNA Polymerase II
  • Ethylmaleimide