Silencing of the gene coding for the epsilon subunit of DNA polymerase III slows down the growth rate of Escherichia coli populations

FEBS Lett. 2003 Jul 10;546(2-3):295-9. doi: 10.1016/s0014-5793(03)00604-5.

Abstract

Chromosome replication in Escherichia coli is accomplished by the multimeric enzyme DNA polymerase III; the relevance, in vivo, of the epsilon subunit (encoded by dnaQ) for processivity and fidelity of DNA polymerase III has been evaluated. To this aim, dnaQ has been conditionally silenced by means of in vivo expression of different antisense RNAs. Unexpectedly, the presence of the Shine-Dalgarno sequence is essential for the effectiveness of antisense constructs. Silencing of dnaQ induces a severe decrease in growth rate not paralleled by high mutation frequencies, suggesting that the epsilon subunit primarily affects the processivity of DNA polymerase III.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Base Sequence
  • Blotting, Northern
  • Cloning, Molecular
  • DNA Polymerase III*
  • Escherichia coli / growth & development*
  • Escherichia coli Proteins*
  • Exodeoxyribonuclease V
  • Exodeoxyribonucleases / genetics*
  • Gene Silencing*
  • Genes, Bacterial*
  • Molecular Sequence Data
  • Nucleic Acid Conformation
  • RNA, Antisense / chemistry

Substances

  • Escherichia coli Proteins
  • RNA, Antisense
  • DNA Polymerase III
  • dnaQ protein, E coli
  • Exodeoxyribonucleases
  • Exodeoxyribonuclease V