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Ion counting demonstrates a high electrostatic field generated by the nucleosome
In eukaryotes, a first step towards the nuclear DNA compaction process is the formation of a nucleosome, which is comprised of negatively charged DNA wrapped around a positively charged histone protein octamer. Often, it is assumed that the complexation of the DNA into the nucleosome completely atte...
Autores principales: | , , , |
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Formato: | Online Artículo Texto |
Lenguaje: | English |
Publicado: |
eLife Sciences Publications, Ltd
2019
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Materias: | |
Acceso en línea: | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6584128/ https://www.ncbi.nlm.nih.gov/pubmed/31184587 http://dx.doi.org/10.7554/eLife.44993 |
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author | Gebala, Magdalena Johnson, Stephanie L Narlikar, Geeta J Herschlag, Dan |
author_facet | Gebala, Magdalena Johnson, Stephanie L Narlikar, Geeta J Herschlag, Dan |
author_sort | Gebala, Magdalena |
collection | PubMed |
description | In eukaryotes, a first step towards the nuclear DNA compaction process is the formation of a nucleosome, which is comprised of negatively charged DNA wrapped around a positively charged histone protein octamer. Often, it is assumed that the complexation of the DNA into the nucleosome completely attenuates the DNA charge and hence the electrostatic field generated by the molecule. In contrast, theoretical and computational studies suggest that the nucleosome retains a strong, negative electrostatic field. Despite their fundamental implications for chromatin organization and function, these opposing views of nucleosome electrostatics have not been experimentally tested. Herein, we directly measure nucleosome electrostatics and find that while nucleosome formation reduces the complex charge by half, the nucleosome nevertheless maintains a strong negative electrostatic field. Our studies highlight the importance of considering the polyelectrolyte nature of the nucleosome and its impact on processes ranging from factor binding to DNA compaction. |
format | Online Article Text |
id | pubmed-6584128 |
institution | National Center for Biotechnology Information |
language | English |
publishDate | 2019 |
publisher | eLife Sciences Publications, Ltd |
record_format | MEDLINE/PubMed |
spelling | pubmed-65841282019-06-21 Ion counting demonstrates a high electrostatic field generated by the nucleosome Gebala, Magdalena Johnson, Stephanie L Narlikar, Geeta J Herschlag, Dan eLife Chromosomes and Gene Expression In eukaryotes, a first step towards the nuclear DNA compaction process is the formation of a nucleosome, which is comprised of negatively charged DNA wrapped around a positively charged histone protein octamer. Often, it is assumed that the complexation of the DNA into the nucleosome completely attenuates the DNA charge and hence the electrostatic field generated by the molecule. In contrast, theoretical and computational studies suggest that the nucleosome retains a strong, negative electrostatic field. Despite their fundamental implications for chromatin organization and function, these opposing views of nucleosome electrostatics have not been experimentally tested. Herein, we directly measure nucleosome electrostatics and find that while nucleosome formation reduces the complex charge by half, the nucleosome nevertheless maintains a strong negative electrostatic field. Our studies highlight the importance of considering the polyelectrolyte nature of the nucleosome and its impact on processes ranging from factor binding to DNA compaction. eLife Sciences Publications, Ltd 2019-06-11 /pmc/articles/PMC6584128/ /pubmed/31184587 http://dx.doi.org/10.7554/eLife.44993 Text en © 2019, Gebala et al http://creativecommons.org/licenses/by/4.0/ http://creativecommons.org/licenses/by/4.0/This article is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0/) , which permits unrestricted use and redistribution provided that the original author and source are credited. |
spellingShingle | Chromosomes and Gene Expression Gebala, Magdalena Johnson, Stephanie L Narlikar, Geeta J Herschlag, Dan Ion counting demonstrates a high electrostatic field generated by the nucleosome |
title | Ion counting demonstrates a high electrostatic field generated by the nucleosome |
title_full | Ion counting demonstrates a high electrostatic field generated by the nucleosome |
title_fullStr | Ion counting demonstrates a high electrostatic field generated by the nucleosome |
title_full_unstemmed | Ion counting demonstrates a high electrostatic field generated by the nucleosome |
title_short | Ion counting demonstrates a high electrostatic field generated by the nucleosome |
title_sort | ion counting demonstrates a high electrostatic field generated by the nucleosome |
topic | Chromosomes and Gene Expression |
url | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6584128/ https://www.ncbi.nlm.nih.gov/pubmed/31184587 http://dx.doi.org/10.7554/eLife.44993 |
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