Involvement of specialized DNA polymerases in mutagenesis by 8-hydroxy-dGTP in human cells

DNA Repair (Amst). 2009 May 1;8(5):637-42. doi: 10.1016/j.dnarep.2008.12.009.

Abstract

The mutagenicity of an oxidized form of dGTP, 8-hydroxy-2'-deoxyguanosine 5'-triphosphate (8-OH-dGTP), was examined using human 293T cells. Shuttle plasmid DNA containing the supF gene was first transfected into the cells, and then 8-OH-dGTP was introduced by means of osmotic pressure. The DNAs replicated in the cells were recovered and then transfected into Escherichia coli. 8-OH-dGTP induced A:T-->C:G substitution mutations in the cells. The knock-downs of DNA polymerases eta and zeta, and REV1 by siRNAs reduced the A:T-->C:G substitution mutations, suggesting that these DNA polymerases are involved in the misincorporation of 8-OH-dGTP opposite A in human cells. In contrast, the knock-down of DNA polymerase iota did not affect the 8-OH-dGTP-induced mutations. The decrease in the induced mutation frequency was more evident by double knock-downs of DNA pols eta plus zeta and REV1 plus DNA pol zeta (but not by that of DNA pol eta plus REV1), suggesting that REV1-DNA pol eta and DNA pol zeta work in different steps. These results indicate that specialized DNA polymerases are involved in the mutagenesis induced by the oxidized dGTP.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • 8-Hydroxy-2'-Deoxyguanosine
  • Cell Line
  • Cells, Cultured
  • DNA-Directed DNA Polymerase / genetics
  • DNA-Directed DNA Polymerase / metabolism*
  • Deoxyguanine Nucleotides / pharmacology*
  • Escherichia coli / genetics
  • Humans
  • Kidney / metabolism
  • Mutagenesis
  • Mutation / genetics*
  • Nuclear Proteins / antagonists & inhibitors
  • Nuclear Proteins / genetics
  • Nuclear Proteins / metabolism*
  • Nucleic Acid Synthesis Inhibitors
  • Nucleotidyltransferases / antagonists & inhibitors
  • Nucleotidyltransferases / genetics
  • Nucleotidyltransferases / metabolism*
  • RNA, Messenger / genetics
  • RNA, Messenger / metabolism
  • RNA, Small Interfering / pharmacology
  • Reverse Transcriptase Polymerase Chain Reaction
  • Transfection

Substances

  • 8-hydroxy-2'-deoxyguanosine 5'-triphosphate
  • Deoxyguanine Nucleotides
  • Nuclear Proteins
  • Nucleic Acid Synthesis Inhibitors
  • RNA, Messenger
  • RNA, Small Interfering
  • 8-Hydroxy-2'-Deoxyguanosine
  • DNA polymerase iota
  • DNA polymerase zeta
  • Nucleotidyltransferases
  • REV1 protein, human
  • DNA-Directed DNA Polymerase