title: A metastable structure for the compact 30-nm chromatin fibre.
abstract: The structure of compact 30-nm chromatin fibres is still debated. We present here a novel unified model that reconciles all experimental observations into a single framework. We propose that compact fibres are formed by the interdigitation of the two nucleosome stacks in a 2-start crossed-linker structure to form a single stack. This process requires that the dyad orientation of successive nucleosomes relative to the helical axis alternates. The model predicts that, as observed experimentally, the fibre-packing density should increase in a stepwise manner with increasing linker length. This model structure can also incorporate linker DNA of varying lengths.
authors.affiliation: Molecular Biophysics Laboratories, School of Biological Sciences, University of Portsmouth, UK.
authors.forename: Chenyi
authors.initials: C
authors.lastname: Wu
authors.affiliation: Molecular Biophysics Laboratories, School of Biological Sciences, University of Portsmouth, UK.
authors.forename: John E
authors.initials: JE
authors.lastname: McGeehan
authors.affiliation: MRC Laboratory of Molecular Biology, Cambridge, UK.|Department of Biochemistry, University of Cambridge, UK.
authors.forename: Andrew
authors.initials: A
authors.lastname: Travers
mesh_terms: D000818:Animals; D002843:Chromatin / Q000737:chemistry* / Q000378:metabolism; D043171:Chromosomal Instability; D004278:DNA, Superhelical / Q000737:chemistry / Q000378:metabolism; D019281:Dimerization; D006801:Humans; D008958:Models, Molecular; D008968:Molecular Conformation; D009707:Nucleosomes / Q000737:chemistry / Q000378:metabolism
chemical_list: D002843:Chromatin; D004278:DNA, Superhelical; D009707:Nucleosomes
keywords: 30-nm fibre; DNA supercoiling; chromatin structure; interdigitation; nucleosome