Similar-sized daughter-strand gaps are produced in the leading and lagging strands of DNA in UV-irradiated E. coli uvrA cells

Biochem Biophys Res Commun. 1992 May 15;184(3):1496-503. doi: 10.1016/s0006-291x(05)80052-x.

Abstract

The nascent DNA synthesized after UV irradiation contained discontinuity, i.e., daughter-strand gaps. The sizes of these gaps produced in the leading and lagging strands of UV-irradiated Escherichia coli cells were determined by using strand-specific DNA probes. The DNA isolated from irradiated uvrA delta(lac-pro) cells was hybridized with the 32P-labeled single-stranded DNA probes. After digestion with S1 nuclease, the sizes of the bound radioactive DNA fragments were determined by electrophoresis in an alkaline agarose gel. It was found that the average size of gaps produced in the leading strand was about 0.12 kb, whereas those produced in the lagging strand was slightly smaller than 0.12 kb. No gaps larger than 0.5 kb were detected.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Coliphages / metabolism
  • DNA Damage*
  • DNA Probes
  • DNA Replication / radiation effects
  • DNA, Bacterial / genetics
  • DNA, Bacterial / isolation & purification
  • DNA, Bacterial / radiation effects*
  • Electrophoresis, Agar Gel
  • Escherichia coli / genetics
  • Escherichia coli / radiation effects*
  • Molecular Weight
  • Nucleic Acid Hybridization
  • Restriction Mapping
  • Thymine / metabolism
  • Ultraviolet Rays*

Substances

  • DNA Probes
  • DNA, Bacterial
  • Thymine