The Escherichia coli regulator of sigma 70 protein, Rsd, can up-regulate some stress-dependent promoters by sequestering sigma 70 Academic Article uri icon


MeSH Major

  • DNA-Directed RNA Polymerases
  • Escherichia coli
  • Escherichia coli Proteins
  • Gene Expression Regulation, Bacterial
  • Promoter Regions, Genetic
  • Repressor Proteins
  • Sigma Factor


  • The Escherichia coli Rsd protein forms complexes with the RNA polymerase sigma(70) factor, but its biological role is not understood. Transcriptome analysis shows that overexpression of Rsd causes increased expression from some promoters whose expression depends on the alternative sigma(38) factor, and this was confirmed by experiments with lac fusions at selected promoters. The LP18 substitution in Rsd increases the Rsd-dependent stimulation of these promoter-lac fusions. Analysis with a bacterial two-hybrid system shows that the LP18 substitution in Rsd increases its interaction with sigma(70). Our experiments support a model in which the role of Rsd is primarily to sequester sigma(70), thereby increasing the levels of RNA polymerase containing the alternative sigma(38) factor.

publication date

  • May 2007



  • Academic Article



  • eng

PubMed Central ID

  • PMC1855875

Digital Object Identifier (DOI)

  • 10.1128/JB.00019-07

PubMed ID

  • 17351046

Additional Document Info

start page

  • 3489

end page

  • 95


  • 189


  • 9