Characterization of chromoshadow domain-mediated binding of heterochromatin protein 1α (HP1α) to histone H3

J Biol Chem. 2012 May 25;287(22):18730-7. doi: 10.1074/jbc.M111.337204. Epub 2012 Apr 9.

Abstract

The chromoshadow domain (CSD) of heterochromatin protein 1 (HP1) was recently shown to contribute to chromatin binding and transcriptional regulation through interaction with histone H3. Here, we demonstrate the structural basis of this interaction for the CSD of HP1α. This mode of H3 binding is dependent on dimerization of the CSD and recognition of a PxVxL-like motif, as for other CSD partners. NMR chemical shift mapping showed that the H3 residues that mediate the CSD interaction occur in and adjacent to the αN helix just within the nucleosome core. Access to the binding region would require some degree of unwrapping of the DNA near the nucleosomal DNA entry/exit site.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Dimerization
  • Heterochromatin / chemistry
  • Heterochromatin / metabolism*
  • Histones / metabolism*
  • Humans
  • Models, Molecular
  • Molecular Sequence Data

Substances

  • Heterochromatin
  • Histones