1. Academic Validation
  2. CENP-C directs a structural transition of CENP-A nucleosomes mainly through sliding of DNA gyres

CENP-C directs a structural transition of CENP-A nucleosomes mainly through sliding of DNA gyres

  • Nat Struct Mol Biol. 2016 Mar;23(3):204-208. doi: 10.1038/nsmb.3175.
Samantha J Falk # 1 Jaehyoun Lee # 2 Nikolina Sekulic 1 Michael A Sennett 2 Tae-Hee Lee 2 Ben E Black 1
Affiliations

Affiliations

  • 1 Department of Biochemistry and Biophysics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA.
  • 2 Department of Chemistry, The Pennsylvania State University, University Park, PA, USA.
  • # Contributed equally.
Abstract

The histone H3 variant CENP-A is incorporated into nucleosomes that mark centromere location. We have recently reported that CENP-A nucleosomes, compared with their H3 counterparts, confer an altered nucleosome shape. Here, using a single-molecule fluorescence resonance energy transfer (FRET) approach with recombinant human histones and centromere DNA, we found that the nucleosome shape change directed by CENP-A is dominated by lateral passing of two DNA gyres (gyre sliding). A nonhistone centromere protein, CENP-C, binds and reshapes the nucleosome, sliding the DNA gyres back to positions similar to those in canonical nucleosomes containing conventional histone H3. The model that we generated to explain the CENP-A-nucleosome transition provides an example of a shape change imposed by external binding proteins and has notable implications for understanding of the epigenetic basis of the faithful inheritance of centromere location on chromosomes.

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