Single-molecule studies on the mechanical interplay between DNA supercoiling and H-NS DNA architectural properties

Ci Ji Lim, Linda Kenney, Jie Yan

Research output: Contribution to journalArticle

20 Scopus citations


The Escherichia coli H-NS protein is a major nucleoid-associated protein that is involved in chromosomal DNA packaging and gene regulatory functions. These biological processes are intimately related to the DNA supercoiling state and thus suggest a direct relationship between H-NS binding and DNA supercoiling. Here, we show that H-NS, which has two distinct DNA-binding modes, is able to differentially regulate DNA supercoiling. H-NS DNA-stiffening mode caused by nucleoprotein filament formation is able to suppress DNA plectoneme formation during DNA supercoiling. In contrast, when H-NS is in its DNA-bridging mode, it is able to promote DNA plectoneme formation during DNA supercoiling. In addition, the DNA-bridging mode is able to block twists diffusion thus trapping DNA in supercoiled domains. Overall, this work reveals the mechanical interplay between H-NS and DNA supercoiling which provides insights to H-NS organization of chromosomal DNA based on its two distinct DNA architectural properties.

Original languageEnglish (US)
Pages (from-to)8369-8378
Number of pages10
JournalNucleic acids research
Issue number13
StatePublished - Jan 1 2014
Externally publishedYes


ASJC Scopus subject areas

  • Genetics

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