A Complex Nucleoprotein Structure Involved in Activation of Transcription of Two Divergent Escherichia Coli Promoters

J Mol Biol. 1989 Feb 5;205(3):471-85. doi: 10.1016/0022-2836(89)90218-0.

Abstract

Initiation of transcription at malEp and malKp, two divergent Escherichia coli promoters, depends on the presence of both CRP, a pleiotropic activator, and MalT, the maltose regulon activator. We carried out in vivo genetic and functional analysis of these promoters and characterized their interaction with MalT and CRP using DNase I footprinting. The functional limits of the promoters are located about 240 base-pairs (bp) upstream of their transcription start sites, which are 271 bp apart. These promoters therefore overlap by about 210 bp. The overlapping region encompasses four CRP-binding sites and at least four MalT-binding sites. Insertions in the centre of this region are tolerated provided that they correspond to an integral number of DNA helix turns. In DNase I footprinting experiments performed on the complex formed by MalT with malEp-malKp, the DNA appears to be wrapped around the protein. We propose a model for the nucleoprotein structure that might be involved in transcription activation at these divergent promoters.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Bacterial Proteins / genetics*
  • Base Sequence
  • Chromosome Deletion
  • DNA Transposable Elements
  • DNA, Bacterial / genetics
  • DNA-Binding Proteins*
  • Escherichia coli
  • Escherichia coli Proteins*
  • Genes, Bacterial*
  • Molecular Sequence Data
  • Nucleoproteins / genetics*
  • Promoter Regions, Genetic*
  • Receptors, Cyclic AMP / genetics
  • Regulatory Sequences, Nucleic Acid
  • Transcription Factors*
  • Transcription, Genetic*

Substances

  • Bacterial Proteins
  • DNA Transposable Elements
  • DNA, Bacterial
  • DNA-Binding Proteins
  • Escherichia coli Proteins
  • MalT protein, E coli
  • Nucleoproteins
  • Receptors, Cyclic AMP
  • Transcription Factors