Jove
Visualize
Contact Us
JoVE
x logofacebook logolinkedin logoyoutube logo
ABOUT JoVE
OverviewLeadershipBlogJoVE Help Center
AUTHORS
Publishing ProcessEditorial BoardScope & PoliciesPeer ReviewFAQSubmit
LIBRARIANS
TestimonialsSubscriptionsAccessResourcesLibrary Advisory BoardFAQ
RESEARCH
JoVE JournalMethods CollectionsJoVE Encyclopedia of ExperimentsArchive
EDUCATION
JoVE CoreJoVE BusinessJoVE Science EducationJoVE Lab ManualFaculty Resource CenterFaculty Site
Terms & Conditions of Use
Privacy Policy
Policies

Related Experiment Videos

The histone octamer, a conformationally flexible structure.

K Park1, G D Fasman

  • 1Graduate Department of Biochemistry, Brandeis University, Waltham, Massachusetts 02254.

Biochemistry
|December 15, 1987
PubMed
Summary

Histone octamer structure changes with salt concentration and type. Circular dichroism reveals distinct alpha-helix and beta-sheet percentages in different salt solutions, explaining X-ray crystallography discrepancies.

Related Concept Videos

You might also read

Related Articles

Articles linked to this work by shared authors, journal, and citation graph.

Sort by
Same author

The interaction of bacteriophage P2 B protein with Escherichia coli DnaB helicase.

Journal of virology·2001
Same author

Connexin26 mutations associated with nonsyndromic hearing loss.

The Laryngoscope·2000
Same author

Functional roles of Na+/H+ exchanger isoforms in saliva secretion.

Journal of Korean medical science·2000
Same author

Expression of volume-activated anion channels in exocrine acinar cells.

Journal of Korean medical science·2000
Same author

Race and sex influence clearance of nifedipine: results of a population study.

Clinical pharmacology and therapeutics·2000
Same author

Formulation and in vivo evaluation of omeprazole buccal adhesive tablet.

Journal of controlled release : official journal of the Controlled Release Society·2000

Area of Science:

  • Biochemistry
  • Structural Biology
  • Biophysics

Background:

  • The histone octamer is a core component of chromatin, essential for DNA packaging.
  • Understanding its solution conformation is crucial for elucidating DNA-protein interactions.
  • Previous X-ray crystallography studies yielded conflicting structural data.

Purpose of the Study:

  • To investigate the solution conformation of the histone octamer complex.
  • To determine the influence of salt concentration and type on histone octamer structure.
  • To reconcile discrepancies observed in X-ray crystallographic analyses.

Main Methods:

  • Circular dichroism (CD) spectroscopy was employed to analyze protein secondary structure.
  • Histone octamer complex was studied in varying salt concentrations and types, specifically NaCl and (NH4)2SO4.
  • Spectroscopic data were analyzed to quantify percentages of alpha-helix, beta-sheet, and random coil structures.

Main Results:

  • Histone octamer conformation is highly sensitive to salt milieu and concentration.
  • In 2 M NaCl, the complex exhibited 43.5% alpha-helix, 16% beta-sheet, and 40.5% random structure.
  • In 2.3 M (NH4)2SO4, the octamer showed 49.0% alpha-helix and 51% random structure.

Conclusions:

  • Solution conditions, particularly salt type and concentration, significantly alter histone octamer conformation.
  • Observed structural changes provide a partial explanation for variable results in X-ray crystallography.
  • These findings highlight the importance of considering solution environment in structural studies of the histone octamer.

Related Experiment Videos