title: Horizontally acquired homologues of the nucleoid-associated protein H-NS: implications for gene regulation.
abstract: H-NS is one of the most intensively studied members of the family of bacterial nucleoid-associated proteins. It is a DNA-binding protein with a preference for A+T-rich DNA sequences, and it represses the transcription of hundreds of genes in Gram-negative bacteria, including pathogens. In most cases where the issue has been investigated, the repressive activity of H-NS is opposed by the intervention of an antagonistically acting DNA-binding protein, a remodelling of local DNA structure, or a combination of these two. H-NS activity can also be modulated by protein-protein interaction with members of the Hha/YdgT protein family, molecules that share partial amino acid sequence similarity to the oligomerization domain of H-NS. Of particular interest is the ability of H-NS to interact with the full-length paralogue StpA or full-length orthologues that have been acquired by horizontal DNA transfer. In this issue of Molecular Microbiology, Müller et al. describe the H-NS orthologue Hfp and present evidence that in bacteria that acquire Hfp the range of activities of H-NS is modified with important implications for the physiology of the bacterium.
authors.affiliation: Department of Microbiology, Moyne Institute of Preventive Medicine, School of Genetics and Microbiology, Trinity College Dublin, Dublin 2, Ireland. cjdorman@tcd.ie
authors.forename: Charles J
authors.initials: CJ
authors.lastname: Dorman
mesh_terms: D001425:Bacterial Outer Membrane Proteins / Q000235:genetics / Q000378:metabolism; D001426:Bacterial Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D004269:DNA, Bacterial / Q000235:genetics; D004268:DNA-Binding Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D019281:Dimerization; D048168:Escherichia coli K12 / Q000235:genetics* / Q000254:growth & development / Q000472:pathogenicity; D029968:Escherichia coli Proteins / Q000235:genetics / Q000378:metabolism; D015964:Gene Expression Regulation, Bacterial; D018832:Molecular Chaperones / Q000235:genetics
chemical_list: D001425:Bacterial Outer Membrane Proteins; D001426:Bacterial Proteins; D004269:DNA, Bacterial; D004268:DNA-Binding Proteins; D029968:Escherichia coli Proteins; C031908:H-NS protein, bacteria; D018832:Molecular Chaperones; C090104:StpA protein, E coli