H-NS forms a superhelical protein scaffold for DNA condensation

Stefan Arold, Paul G. Leonard, Gary N. Parkinson, John E. Ladbury

Research output: Contribution to journalArticlepeer-review

123 Scopus citations

Abstract

The histone-like nucleoid structuring (H-NS) protein plays a fundamental role in DNA condensation and is a key regulator of enterobacterial gene expression in response to changes in osmolarity, pH, and temperature. The protein is capable of high-order self-association via interactions of its oligomerization domain. Using crystallography, we have solved the structure of this complete domain in an oligomerized state. The observed superhelical structure establishes a mechanism for the self-association of H-NS via both an N-terminal antiparallel coiled-coil and a second, hitherto unidentified, helix-turn-helix dimerization interface at the C-terminal end of the oligomerization domain. The helical scaffold suggests the formation of a H-NS:plectonemic DNA nucleoprotein complex that is capable of explaining published biophysical and functional data, and establishes a unifying structural basis for coordinating the DNA packaging and transcription repression functions of H-NS.

Original languageEnglish (US)
Pages (from-to)15728-15732
Number of pages5
JournalProceedings of the National Academy of Sciences of the United States of America
Volume107
Issue number36
DOIs
StatePublished - Sep 7 2010

Keywords

  • Chromatin
  • DNA binding
  • Nucleoid
  • Supercoil
  • Transcriptional regulation

ASJC Scopus subject areas

  • General

Cite this