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Proc Natl Acad Sci U S A
2017 Jan 10;1142:334-339. doi: 10.1073/pnas.1611118114.
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Asymmetric unwrapping of nucleosomal DNA propagates asymmetric opening and dissociation of the histone core.
Chen Y
,
Tokuda JM
,
Topping T
,
Meisburger SP
,
Pabit SA
,
Gloss LM
,
Pollack L
.
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The nucleosome core particle (NCP) is the basic structural unit for genome packaging in eukaryotic cells and consists of DNA wound around a core of eight histone proteins. DNA access is modulated through dynamic processes of NCP disassembly. Partly disassembled structures, such as the hexasome (containing six histones) and the tetrasome (four histones), are important for transcription regulation in vivo. However, the pathways for their formation have been difficult to characterize. We combine time-resolved (TR) small-angle X-ray scattering and TR-FRET to correlate changes in the DNA conformations with composition of the histone core during salt-induced disassembly of canonical NCPs. We find that H2A-H2B histone dimers are released sequentially, with the first dimer being released after the DNA has formed an asymmetrically unwrapped, teardrop-shape DNA structure. This finding suggests that the octasome-to-hexasome transition is guided by the asymmetric unwrapping of the DNA. The link between DNA structure and histone composition suggests a potential mechanism for the action of proteins that alter nucleosome configurations such as histone chaperones and chromatin remodeling complexes.
Andrews,
Nucleosome structure(s) and stability: variations on a theme.
2011, Pubmed
Andrews,
Nucleosome structure(s) and stability: variations on a theme.
2011,
Pubmed
Arimura,
Structural analysis of the hexasome, lacking one histone H2A/H2B dimer from the conventional nucleosome.
2012,
Pubmed
Banks,
Equilibrium folding of the core histones: the H3-H4 tetramer is less stable than the H2A-H2B dimer.
2003,
Pubmed
Beechem,
Global analysis of biochemical and biophysical data.
1992,
Pubmed
Bell,
Determinants and dynamics of genome accessibility.
2011,
Pubmed
Belotserkovskaya,
FACT facilitates transcription-dependent nucleosome alteration.
2003,
Pubmed
Bernadó,
Structural characterization of flexible proteins using small-angle X-ray scattering.
2007,
Pubmed
Blose,
Effects of a protecting osmolyte on the ion atmosphere surrounding DNA duplexes.
2011,
Pubmed
Bowman,
Mechanisms of ATP-dependent nucleosome sliding.
2010,
Pubmed
Brower-Toland,
Mechanical disruption of individual nucleosomes reveals a reversible multistage release of DNA.
2002,
Pubmed
Böhm,
Nucleosome accessibility governed by the dimer/tetramer interface.
2011,
Pubmed
Chen,
Revealing transient structures of nucleosomes as DNA unwinds.
2014,
Pubmed
,
Xenbase
Chua,
The mechanics behind DNA sequence-dependent properties of the nucleosome.
2012,
Pubmed
,
Xenbase
Gloss,
The effect of salts on the stability of the H2A-H2B histone dimer.
2002,
Pubmed
,
Xenbase
González,
Interaction of RNA polymerase II with structurally altered nucleosomal particles. Transcription is facilitated by loss of one H2A.H2B dimer.
1989,
Pubmed
Hall,
High-resolution dynamic mapping of histone-DNA interactions in a nucleosome.
2009,
Pubmed
Hazan,
Nucleosome Core Particle Disassembly and Assembly Kinetics Studied Using Single-Molecule Fluorescence.
2015,
Pubmed
,
Xenbase
Hoch,
Protein-protein Förster resonance energy transfer analysis of nucleosome core particles containing H2A and H2A.Z.
2007,
Pubmed
,
Xenbase
Katan,
Dynamics of nucleosomal structures measured by high-speed atomic force microscopy.
2015,
Pubmed
Kireeva,
Nucleosome remodeling induced by RNA polymerase II: loss of the H2A/H2B dimer during transcription.
2002,
Pubmed
Li,
Rapid spontaneous accessibility of nucleosomal DNA.
2005,
Pubmed
Li,
Nucleosomes facilitate their own invasion.
2004,
Pubmed
,
Xenbase
Lowary,
New DNA sequence rules for high affinity binding to histone octamer and sequence-directed nucleosome positioning.
1998,
Pubmed
Luger,
Crystal structure of the nucleosome core particle at 2.8 A resolution.
1997,
Pubmed
Luger,
Dynamic nucleosomes.
2006,
Pubmed
Mazurkiewicz,
On the mechanism of nucleosome assembly by histone chaperone NAP1.
2006,
Pubmed
Miyagi,
Dynamics of nucleosomes assessed with time-lapse high-speed atomic force microscopy.
2011,
Pubmed
Ngo,
Asymmetric unwrapping of nucleosomes under tension directed by DNA local flexibility.
2015,
Pubmed
,
Xenbase
Oohara,
Spectroscopic studies on histone-DNA interactions. I. The interaction of histone (H2A, H2B) dimer with DNA: DNA sequence dependence.
1987,
Pubmed
Oohara,
Spectroscopic studies on histone-DNA interactions. II. Three transitions in nucleosomes resolved by salt-titration.
1987,
Pubmed
Park,
A new fluorescence resonance energy transfer approach demonstrates that the histone variant H2AZ stabilizes the histone octamer within the nucleosome.
2004,
Pubmed
,
Xenbase
Pelikan,
Structure and flexibility within proteins as identified through small angle X-ray scattering.
2009,
Pubmed
Tims,
Dynamics of nucleosome invasion by DNA binding proteins.
2011,
Pubmed
Tria,
Advanced ensemble modelling of flexible macromolecules using X-ray solution scattering.
2015,
Pubmed
Yen,
SWR-C and INO80 chromatin remodelers recognize nucleosome-free regions near +1 nucleosomes.
2013,
Pubmed
Zlatanova,
The nucleosome family: dynamic and growing.
2009,
Pubmed
