ASF1 binds to a heterodimer of histones H3 and H4: a two-step mechanism for the assembly of the H3-H4 heterotetramer on DNA

Biochemistry. 2005 Oct 25;44(42):13673-82. doi: 10.1021/bi051333h.


The first step in the formation of the nucleosome is commonly assumed to be the deposition of a histone H3-H4 heterotetramer onto DNA. Antisilencing function 1 (ASF1) is a major histone H3-H4 chaperone that deposits histones H3 and H4 onto DNA. With a goal of understanding the mechanism of deposition of histones H3 and H4 onto DNA, we have determined the stoichiometry of the Asf1-H3-H4 complex. We have established that a single molecule of Asf1 binds to an H3-H4 heterodimer using gel filtration, amino acid, reversed-phase chromatography, and analytical ultracentrifugation analyses. We demonstrate that Asf1 blocks formation of the H3-H4 heterotetramer by a mechanism that likely involves occlusion of the H3-H3 dimerization interface.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Cell Cycle Proteins / chemistry
  • Cell Cycle Proteins / metabolism*
  • Chromatography, Gel
  • Chromatography, High Pressure Liquid
  • DNA / metabolism*
  • Dimerization
  • Histones / chemistry
  • Histones / metabolism*
  • Molecular Chaperones
  • Molecular Weight
  • Nucleosomes / metabolism
  • Saccharomyces cerevisiae Proteins / chemistry
  • Saccharomyces cerevisiae Proteins / metabolism*
  • Ultracentrifugation


  • ASF1 protein, S cerevisiae
  • Cell Cycle Proteins
  • Histones
  • Molecular Chaperones
  • Nucleosomes
  • Saccharomyces cerevisiae Proteins
  • DNA