Basic surface features of nuclear FKBPs facilitate chromatin binding

Sci Rep. 2017 Jun 19;7(1):3795. doi: 10.1038/s41598-017-04194-7.

Abstract

The nucleoplasmin family of histone chaperones is identified by a pentamer-forming domain and multiple acidic tracts that mediate histone binding and chaperone activity. Within this family, a novel domain organization was recently discovered that consists of an N-terminal nucleoplasmin-like (NPL) domain and a C-terminal FKBP peptidyl-proline isomerase domain. Saccharomyces cerevisiae Fpr4 is one such protein. Here we report that in addition to its known histone prolyl isomerase activities, the Fpr4 FKBP domain binds to nucleosomes and nucleosome arrays in vitro. This ability is mediated by a collection of basic patches that enable the enzyme to stably associate with linker DNA. The interaction of the Fpr4 FKBP with recombinant chromatin complexes condenses nucleosome arrays independently of its catalytic activity. Based on phylogenetic comparisons we propose that the chromatin binding ability of 'basic' FKBPs is shared amongst related orthologues present in fungi, plants, and insects. Thus, a subclass of FKBP prolyl isomerase enzymes is recruited to linker regions of chromatin.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Histone Chaperones / chemistry*
  • Histone Chaperones / genetics
  • Histone Chaperones / metabolism
  • Humans
  • Nucleosomes / chemistry*
  • Nucleosomes / genetics
  • Nucleosomes / metabolism
  • Protein Domains
  • Saccharomyces cerevisiae / chemistry*
  • Saccharomyces cerevisiae / genetics
  • Saccharomyces cerevisiae / metabolism
  • Saccharomyces cerevisiae Proteins / chemistry*
  • Saccharomyces cerevisiae Proteins / genetics
  • Saccharomyces cerevisiae Proteins / metabolism
  • Tacrolimus Binding Proteins / chemistry*
  • Tacrolimus Binding Proteins / genetics
  • Tacrolimus Binding Proteins / metabolism

Substances

  • Histone Chaperones
  • Nucleosomes
  • Saccharomyces cerevisiae Proteins
  • Tacrolimus Binding Proteins
  • Fpr4 protein, S cerevisiae