Growth phase dependent stop codon readthrough and shift of translation reading frame in Escherichia coli

FEBS Lett. 1998 Jan 16;421(3):237-42. doi: 10.1016/s0014-5793(97)01570-6.

Abstract

Nonsense codon readthrough and changed translational reading frame were measured in different growth phases in E. coli. The strains used carry plasmid constructs with a translation assay reporter gene. This reporter gene contains an internal stop codon or a run of U-residues. Termination or frameshifting give rise to stable proteins that can be physically quantified on gels along with the complete protein products. Readthrough of the stop codon UGA by a nearcognate tRNA is several fold higher in active growth than in late exponential phase. In early exponential phase, about 7% of -1 frameshift at a U9 slippery sequence is detectable; upon entry to stationary phase this frameshifting increases to about 40% followed by a decrease in stationary phase. A similar increase is observed in the case of +1 reading frameshift at the U9 sequence, which increases from 13% in early exponential growth phase up to 38% at the beginning of stationary phase followed by a decrease. Thus, the levels of both stop codon readthrough and frameshifting are growth phase dependent, though not in an identical fashion.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Base Sequence
  • Codon, Terminator*
  • DNA, Bacterial
  • Escherichia coli / genetics*
  • Escherichia coli / growth & development
  • Frameshifting, Ribosomal*
  • Molecular Sequence Data
  • Reading Frames*

Substances

  • Codon, Terminator
  • DNA, Bacterial