H-NS mediates the silencing of laterally acquired genes in bacteria

S Lucchini, G Rowley, Martin Goldberg, D Hurd, M Harrison, John Hinton

Research output: Contribution to journalArticle

363 Citations (Scopus)

Abstract

Histone-like nucleoid structuring protein (H-NS) is a modular protein that is associated with the bacterial nucleoid. We used chromatin immunoprecipitation to determine the binding sites of H-NS and RNA polymerase on the Salmonella enterica serovar Typhimurium chromosome. We found that H-NS does not bind to actively transcribed genes and does not co-localize with RNA polymerase. This shows that H-NS principally silences gene expression by restricting the access of RNA polymerase to the DNA. H-NS had previously been shown to preferentially bind to curved DNA in vitro. In fact, at the genomic level we discovered that the level of H-NS binding correlates better with the AT-content of DNA. This is likely to have evolutionary consequences because we show that H-NS binds to many Salmonella genes acquired by lateral gene transfer, and functions as a gene silencer. The removal of H-NS from the cell causes un-controlled expression of several Salmonella pathogenicity islands, and we demonstrate that this has deleterious consequences for bacterial fitness. Our discovery of this novel role for H-NS may have implications for the acquisition of foreign genes by enteric bacteria.
Original languageEnglish
Pages (from-to)1-7
Number of pages7
JournalPLoS pathogens
Volume2
DOIs
Publication statusPublished - 1 Jan 2006

Fingerprint

Dive into the research topics of 'H-NS mediates the silencing of laterally acquired genes in bacteria'. Together they form a unique fingerprint.

Cite this