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Histone H1 compacts DNA under force and during chromatin assembly
Histone H1 binds to linker DNA between nucleosomes, but the dynamics and biological ramifications of this interaction remain poorly understood. We performed single-molecule experiments using magnetic tweezers to determine the effects of H1 on naked DNA in buffer or during chromatin assembly in Xenop...
Autores principales: | , , , , |
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Formato: | Online Artículo Texto |
Lenguaje: | English |
Publicado: |
The American Society for Cell Biology
2012
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Materias: | |
Acceso en línea: | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3521692/ https://www.ncbi.nlm.nih.gov/pubmed/23097493 http://dx.doi.org/10.1091/mbc.E12-07-0518 |
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author | Xiao, Botao Freedman, Benjamin S. Miller, Kelly E. Heald, Rebecca Marko, John F. |
author_facet | Xiao, Botao Freedman, Benjamin S. Miller, Kelly E. Heald, Rebecca Marko, John F. |
author_sort | Xiao, Botao |
collection | PubMed |
description | Histone H1 binds to linker DNA between nucleosomes, but the dynamics and biological ramifications of this interaction remain poorly understood. We performed single-molecule experiments using magnetic tweezers to determine the effects of H1 on naked DNA in buffer or during chromatin assembly in Xenopus egg extracts. In buffer, nanomolar concentrations of H1 induce bending and looping of naked DNA at stretching forces below 0.6 pN, effects that can be reversed with 2.7-pN force or in 200 mM monovalent salt concentrations. Consecutive tens-of-nanometer bending events suggest that H1 binds to naked DNA in buffer at high stoichiometries. In egg extracts, single DNA molecules assemble into nucleosomes and undergo rapid compaction. Histone H1 at endogenous physiological concentrations increases the DNA compaction rate during chromatin assembly under 2-pN force and decreases it during disassembly under 5-pN force. In egg cytoplasm, histone H1 protects sperm nuclei undergoing genome-wide decondensation and chromatin assembly from becoming abnormally stretched or fragmented due to astral microtubule pulling forces. These results reveal functional ramifications of H1 binding to DNA at the single-molecule level and suggest an important physiological role for H1 in compacting DNA under force and during chromatin assembly. |
format | Online Article Text |
id | pubmed-3521692 |
institution | National Center for Biotechnology Information |
language | English |
publishDate | 2012 |
publisher | The American Society for Cell Biology |
record_format | MEDLINE/PubMed |
spelling | pubmed-35216922013-03-02 Histone H1 compacts DNA under force and during chromatin assembly Xiao, Botao Freedman, Benjamin S. Miller, Kelly E. Heald, Rebecca Marko, John F. Mol Biol Cell Articles Histone H1 binds to linker DNA between nucleosomes, but the dynamics and biological ramifications of this interaction remain poorly understood. We performed single-molecule experiments using magnetic tweezers to determine the effects of H1 on naked DNA in buffer or during chromatin assembly in Xenopus egg extracts. In buffer, nanomolar concentrations of H1 induce bending and looping of naked DNA at stretching forces below 0.6 pN, effects that can be reversed with 2.7-pN force or in 200 mM monovalent salt concentrations. Consecutive tens-of-nanometer bending events suggest that H1 binds to naked DNA in buffer at high stoichiometries. In egg extracts, single DNA molecules assemble into nucleosomes and undergo rapid compaction. Histone H1 at endogenous physiological concentrations increases the DNA compaction rate during chromatin assembly under 2-pN force and decreases it during disassembly under 5-pN force. In egg cytoplasm, histone H1 protects sperm nuclei undergoing genome-wide decondensation and chromatin assembly from becoming abnormally stretched or fragmented due to astral microtubule pulling forces. These results reveal functional ramifications of H1 binding to DNA at the single-molecule level and suggest an important physiological role for H1 in compacting DNA under force and during chromatin assembly. The American Society for Cell Biology 2012-12-15 /pmc/articles/PMC3521692/ /pubmed/23097493 http://dx.doi.org/10.1091/mbc.E12-07-0518 Text en © 2012 Xiao et al. This article is distributed by The American Society for Cell Biology under license from the author(s). Two months after publication it is available to the public under an Attribution–Noncommercial–Share Alike 3.0 Unported Creative Commons License (http://creativecommons.org/licenses/by-nc-sa/3.0). “ASCB®,” “The American Society for Cell Biology®,” and “Molecular Biology of the Cell®” are registered trademarks of The American Society of Cell BD; are registered trademarks of The American Society of Cell Biology. |
spellingShingle | Articles Xiao, Botao Freedman, Benjamin S. Miller, Kelly E. Heald, Rebecca Marko, John F. Histone H1 compacts DNA under force and during chromatin assembly |
title | Histone H1 compacts DNA under force and during chromatin assembly |
title_full | Histone H1 compacts DNA under force and during chromatin assembly |
title_fullStr | Histone H1 compacts DNA under force and during chromatin assembly |
title_full_unstemmed | Histone H1 compacts DNA under force and during chromatin assembly |
title_short | Histone H1 compacts DNA under force and during chromatin assembly |
title_sort | histone h1 compacts dna under force and during chromatin assembly |
topic | Articles |
url | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3521692/ https://www.ncbi.nlm.nih.gov/pubmed/23097493 http://dx.doi.org/10.1091/mbc.E12-07-0518 |
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