Effect of salt on the binding of the linker histone HI to DNA and nucleosomes

Zeina Al-Natour, Ahmed H. Hassan

Research output: Contribution to journalArticlepeer-review

5 Citations (Scopus)

Abstract

The linker histones are involved in the salt-dependent folding of the nucleosomes into higher-order chromatin structures. To better understand the mechanism of action of these histones in chromatin, we studied the interactions of the linker histone H1 with DNA at various histone/DNA ratios and at different ionic strengths. In direct competition experiments, we have confirmed the binding of H1 to superhelical DNA in preference to linear or nicked circular DNA forms. We show that the electrophoretic mobility of the H1/supercoiled DNA complex decreases with increasing H1 concentrations and increases with ionic strengths. These results indicate that the interaction of the linker histone H1 with supercoiled DNA results in a soluble binding of H1 with DNA at low H1 or salt concentrations and aggregation at higher H1 concentrations. Moreover, we show that H1 dissociates from the DNA or nucleosomes at high salt concentrations. By the immobilized template pull-down assay, we confirm these data using the physiologically relevant nucleosome array template.

Original languageEnglish
Pages (from-to)445-452
Number of pages8
JournalDNA and Cell Biology
Volume26
Issue number6
DOIs
Publication statusPublished - Jun 2007

ASJC Scopus subject areas

  • Molecular Biology
  • Genetics
  • Cell Biology

Fingerprint

Dive into the research topics of 'Effect of salt on the binding of the linker histone HI to DNA and nucleosomes'. Together they form a unique fingerprint.

Cite this