H-NS family members function coordinately in an opportunistic pathogen

Proc Natl Acad Sci U S A. 2008 Dec 2;105(48):18947-52. doi: 10.1073/pnas.0808215105. Epub 2008 Nov 21.

Abstract

The histone-like nucleoid structuring protein, H-NS, is a prominent global regulator of gene expression. Many Gram-negative bacteria contain multiple members of the H-NS family of proteins. Thus, a key question is whether H-NS family members have overlapping or distinct functions. To address this question we performed genome-wide location analyses with MvaT and MvaU, the two H-NS family members present in Pseudomonas aeruginosa. We show that MvaT and MvaU bind the same chromosomal regions, coregulating the expression of approximately 350 target genes. We show further that like H-NS in enteric bacteria, which functions as a transcriptional silencer of foreign DNA by binding to AT-rich elements, MvaT and MvaU bind preferentially to AT-rich regions of the chromosome. Our findings establish that H-NS paralogs can function coordinately to regulate expression of the same set of target genes, and suggest that MvaT and MvaU are involved in silencing foreign DNA elements in P. aeruginosa.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Bacterial Proteins / genetics
  • Bacterial Proteins / metabolism*
  • Chromosomes, Bacterial
  • DNA-Binding Proteins / genetics
  • DNA-Binding Proteins / metabolism*
  • Gene Expression Regulation, Bacterial*
  • Gene Silencing
  • Humans
  • Pseudomonas aeruginosa / genetics*
  • Pseudomonas aeruginosa / metabolism*
  • Pseudomonas aeruginosa / pathogenicity
  • Regulon
  • Trans-Activators / genetics
  • Trans-Activators / metabolism
  • Transcription, Genetic

Substances

  • Bacterial Proteins
  • DNA-Binding Proteins
  • H-NS protein, bacteria
  • MvaT protein, Pseudomonas
  • Trans-Activators