Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
2011-1-17
pubmed:abstractText
The response regulator SsrB activates expression of genes encoded within and outside of a pathogenicity island (SPI-2), which is required for systemic infection of Salmonella. SsrB binds upstream of the sifA, sifB, and sseJ effector genes and directly regulates transcription. SsrB also relieves gene silencing by the nucleoid protein H-NS. Single molecule experiments with magnetic tweezers demonstrated that SsrB displaces H-NS from DNA only when it is bound in a polymerization (stiffening) mode and not when H-NS is bound to DNA in the bridging mode. Thus, in contrast to previous views, the polymerization binding mode of H-NS is the relevant form for counter-silencing by SsrB. Our results reveal that response regulators can directly activate transcription and also relieve H-NS silencing. This study adds to the repertoire of mechanisms by which NarL/FixJ subfamily members regulate transcription. Because SsrB-dependent promoters are diversely organized, additional mechanisms of transcriptional activation at other loci are likely.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jan
pubmed:issn
1083-351X
pubmed:author
pubmed:issnType
Electronic
pubmed:day
21
pubmed:volume
286
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1895-902
pubmed:meshHeading
pubmed:year
2011
pubmed:articleTitle
Salmonella enterica response regulator SsrB relieves H-NS silencing by displacing H-NS bound in polymerization mode and directly activates transcription.
pubmed:affiliation
Department of Microbiology and Immunology, University of Illinois, Chicago, Illinois 60612, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, Non-P.H.S., Research Support, Non-U.S. Gov't, Research Support, N.I.H., Extramural