title: The H-NS dimerization domain defines a new fold contributing to DNA recognition.
abstract: H-NS, a protein found in Gram-negative bacteria, is involved in structuring the bacterial chromosome and acts as a global regulator for the expression of a wide variety of genes. These functions are correlated with both its DNA-binding and oligomerization properties. We have identified the minimal dimerization domain of H-NS, a 46 amino acid-long N-terminal fragment, and determined its structure using heteronuclear NMR spectroscopy. The highly intertwined structure of the dimer, reminiscent of a handshake, defines a new structural fold, which may offer a possibility for discriminating prokaryotic from eukaryotic proteins in drug design. Using mutational analysis, we also show that this N-terminal domain actively contributes to DNA binding, conversely to the current paradigm. Together, our data allows us to propose a model for the action of full length H-NS.
authors.affiliation: Centre de Biochimie Structurale, CNRS-UMR 5048, INSERM-U554, Université de Montpellier I, 29 rue de Navacelles, 34090 Montpellier, France.
authors.forename: Vanessa
authors.initials: V
authors.lastname: Bloch
authors.forename: Yinshan
authors.initials: Y
authors.lastname: Yang
authors.forename: Emmanuel
authors.initials: E
authors.lastname: Margeat
authors.forename: Alain
authors.initials: A
authors.lastname: Chavanieu
authors.forename: Marie Thérèse
authors.initials: MT
authors.lastname: Augé
authors.forename: Bruno
authors.initials: B
authors.lastname: Robert
authors.forename: Stefan
authors.initials: S
authors.lastname: Arold
authors.forename: Sylvie
authors.initials: S
authors.lastname: Rimsky
authors.forename: Michel
authors.initials: M
authors.lastname: Kochoyan
mesh_terms: D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D017124:Conserved Sequence; D004247:DNA / Q000378:metabolism*; D004268:DNA-Binding Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D019281:Dimerization; D005454:Fluorescence Polarization; D009682:Magnetic Resonance Spectroscopy; D008958:Models, Molecular; D008969:Molecular Sequence Data; D009154:Mutation; D010446:Peptide Fragments / Q000737:chemistry; D011487:Protein Conformation; D017510:Protein Folding; D017434:Protein Structure, Tertiary
chemical_list: D001426:Bacterial Proteins; D004268:DNA-Binding Proteins; C031908:H-NS protein, bacteria; D010446:Peptide Fragments; D004247:DNA