E. coli Fis protein insulates the cbpA gene from uncontrolled transcription

Research output: Contribution to journalArticle

Authors

  • Shivani S. Singh
  • Rajesh Shahapure
  • Remus T. Dame

Colleges, School and Institutes

Abstract

The Escherichia coli curved DNA binding protein A (CbpA) is a poorly characterised nucleoid associated factor and co-chaperone. It is expressed at high levels as cells enter stationary phase. Using genetics, biochemistry, and genomics, we have examined regulation of, and DNA binding by, CbpA. We show that Fis, the dominant growth-phase nucleoid protein, prevents CbpA expression in growing cells. Regulation by Fis involves an unusual “insulation” mechanism. Thus, Fis protects cbpA from the effects of a distal promoter, located in an adjacent gene. In stationary phase, when Fis levels are low, CbpA binds the E. coli chromosome with a preference for the intrinsically curved Ter macrodomain. Disruption of the cbpA gene prompts dramatic changes in DNA topology. Thus, our work identifies a novel role for Fis and incorporates CbpA into the growing network of factors that mediate bacterial chromosome structure.

Details

Original languageEnglish
Article numbere1003152
JournalPLoS Genetics
Volume9
Issue number1
Publication statusPublished - 17 Jan 2013

Keywords

  • Bacterial genomics, Cell binding, Cell fusion, Chromosomes, DNA sequences, DNA transcription, DNA-binding proteins, RNA polymerase