Enhancement of the in vitro transcription by T7 RNA polymerase of short DNA templates containing oxidative thymine lesions

C R Biol. 2005 Sep;328(9):794-801. doi: 10.1016/j.crvi.2005.07.003.

Abstract

5-(Hydroxymethyl)uracil, 5-formyluracil or 5-carboxyuracil can be formed in DNA upon exposure to ionizing radiations. We report the effect of the latter oxidative lesions on the in vitro transcription by T7 RNA polymerase using a single-stranded short model template. Kinetic experiments showed that the transcription yield was increased with the modified template. Due to the unforeseen presence of a hairpin structure within the transcribed RNA, we postulated that we are in the presence of a T7 RNA polymerase pausing signal and that the lesions within this critical DNA structure could interfere with normal regulation of RNA transcription.

MeSH terms

  • Bacteriophage T7 / enzymology
  • Bacteriophage T7 / genetics
  • Base Sequence
  • DNA Damage*
  • DNA Primers
  • DNA-Directed RNA Polymerases / genetics*
  • Kinetics
  • Molecular Sequence Data
  • Nucleic Acid Conformation
  • Oxidative Stress
  • Protozoan Proteins
  • RNA, Viral / chemistry
  • RNA, Viral / genetics
  • Templates, Genetic
  • Thymidine / analogs & derivatives*
  • Transcription, Genetic*
  • Viral Proteins / genetics*

Substances

  • D0295c protein, Plasmodium falciparum
  • DNA Primers
  • Protozoan Proteins
  • RNA, Viral
  • Viral Proteins
  • bacteriophage T7 RNA polymerase
  • DNA-Directed RNA Polymerases
  • Thymidine