title: H-NS, Its Family Members and Their Regulation of Virulence Genes in Shigella Species.
abstract: The histone-like nucleoid structuring protein (H-NS) has played a key role in shaping the evolution ofShigellaspp., and provides the backdrop to the regulatory cascade that controls virulence by silencing many genes found on the large virulence plasmid. H-NS and its paralogue StpA are present in all fourShigellaspp., but a second H-NS paralogue, Sfh, is found in theShigella flexneritype strain 2457T, which is routinely used in studies ofShigellapathogenesis. While StpA and Sfh have been proposed to serve as "molecular backups" for H-NS, the apparent redundancy of these proteins is questioned by in vitro studies and work done inEscherichia coli. In this review, we describe the current understanding of the regulatory activities of the H-NS family members, the challenges associated with studying these proteins and their role in the regulation of virulence genes inShigella.
authors.affiliation: School of Life Sciences, University of Nevada Las Vegas, Las Vegas, NV 89154-4004, USA. pickerm3@unlv.nevada.edu.
authors.forename: Michael A
authors.initials: MA
authors.lastname: Picker
authors.affiliation: School of Life Sciences, University of Nevada Las Vegas, Las Vegas, NV 89154-4004, USA. helen.wing@unlv.edu.
authors.forename: Helen J
authors.initials: HJ
authors.lastname: Wing
keywords: H-NS; Shigella; anti-silencing mechanisms; silencing mechanisms; transcription; virulence gene expression; xenogeneic silencing