A molecular mechanism for the repression of transcription by the H-NS protein.
The H-NS protein is a major component of the bacterial nucleoid and plays a crucial role in the global gene regulation of enteric bacteria. Although H-NS does not exhibit a high DNA sequence specificity, a number of H-NS-responsive promoters have been shown to contain regions of intrinsic DNA curvature located either upstream or downstream of the transcription start point. We have studied H-NS binding to DNA and in vitro transcriptional regulation by H-NS at several synthetic promoters with or without curved sequences inserted upstream of the Pribnow box. We show how such inserts determine the final organization of H-NS-containing nucleoprotein complexes and how this affects transcription. We refine a two-step mechanism for the constitution of H-NS assemblies that are efficient in regulation.
Rimsky
S
S
Unité de Physicochimie des Macromolécules Biologiques, URA 1773 du Centre National de la Recherche Scientifique, Institut Pasteur, F-75724 Paris Cedex 15, France. srimsky@igr.fr
Zuber
F
F
Buckle
M
M
Buc
H
H
D001426:Bacterial Proteins; D001483:Base Sequence; D017931:DNA Primers; D004268:DNA-Binding Proteins / Q000378:metabolism*; D004755:Enterobacteriaceae / Q000235:genetics*; D015964:Gene Expression Regulation, Bacterial; D007700:Kinetics; D011401:Promoter Regions, Genetic; D012097:Repressor Proteins / Q000378:metabolism*; D014158:Transcription, Genetic
D001426:Bacterial Proteins; D017931:DNA Primers; D004268:DNA-Binding Proteins; C031908:H-NS protein, bacteria; D012097:Repressor Proteins