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Internal modifications in the CENP-A nucleosome modulate centromeric dynamics

BACKGROUND: Posttranslational modifications of core histones are correlated with changes in transcriptional status, chromatin fiber folding, and nucleosome dynamics. However, within the centromere-specific histone H3 variant CENP-A, few modifications have been reported, and their functions remain la...

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Autores principales: Bui, Minh, Pitman, Mary, Nuccio, Arthur, Roque, Serene, Donlin-Asp, Paul Gregory, Nita-Lazar, Aleksandra, Papoian, Garegin A., Dalal, Yamini
Formato: Online Artículo Texto
Lenguaje:English
Publicado: BioMed Central 2017
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5379712/
https://www.ncbi.nlm.nih.gov/pubmed/28396698
http://dx.doi.org/10.1186/s13072-017-0124-6
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author Bui, Minh
Pitman, Mary
Nuccio, Arthur
Roque, Serene
Donlin-Asp, Paul Gregory
Nita-Lazar, Aleksandra
Papoian, Garegin A.
Dalal, Yamini
author_facet Bui, Minh
Pitman, Mary
Nuccio, Arthur
Roque, Serene
Donlin-Asp, Paul Gregory
Nita-Lazar, Aleksandra
Papoian, Garegin A.
Dalal, Yamini
author_sort Bui, Minh
collection PubMed
description BACKGROUND: Posttranslational modifications of core histones are correlated with changes in transcriptional status, chromatin fiber folding, and nucleosome dynamics. However, within the centromere-specific histone H3 variant CENP-A, few modifications have been reported, and their functions remain largely unexplored. In this multidisciplinary report, we utilize in silico computational and in vivo approaches to dissect lysine 124 of human CENP-A, which was previously reported to be acetylated in advance of replication. RESULTS: Computational modeling demonstrates that acetylation of K124 causes tightening of the histone core and hinders accessibility to its C-terminus, which in turn diminishes CENP-C binding. Additionally, CENP-A K124ac/H4 K79ac containing nucleosomes are prone to DNA sliding. In vivo experiments using a CENP-A acetyl or unacetylatable mimic (K124Q and K124A, respectively) reveal alterations in CENP-C levels and a modest increase in mitotic errors. Furthermore, mutation of K124 results in alterations in centromeric replication timing. Purification of native CENP-A proteins followed by mass spectrometry analysis reveals that while CENP-A K124 is acetylated at G1/S, it switches to monomethylation during early S and mid-S phases. Finally, we provide evidence implicating the histone acetyltransferase (HAT) p300 in this cycle. CONCLUSIONS: Taken together, our data suggest that cyclical modifications within the CENP-A nucleosome contribute to the binding of key kinetochore proteins, the integrity of mitosis, and centromeric replication. These data support the paradigm that modifications in histone variants can influence key biological processes. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1186/s13072-017-0124-6) contains supplementary material, which is available to authorized users.
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spelling pubmed-53797122017-04-10 Internal modifications in the CENP-A nucleosome modulate centromeric dynamics Bui, Minh Pitman, Mary Nuccio, Arthur Roque, Serene Donlin-Asp, Paul Gregory Nita-Lazar, Aleksandra Papoian, Garegin A. Dalal, Yamini Epigenetics Chromatin Research BACKGROUND: Posttranslational modifications of core histones are correlated with changes in transcriptional status, chromatin fiber folding, and nucleosome dynamics. However, within the centromere-specific histone H3 variant CENP-A, few modifications have been reported, and their functions remain largely unexplored. In this multidisciplinary report, we utilize in silico computational and in vivo approaches to dissect lysine 124 of human CENP-A, which was previously reported to be acetylated in advance of replication. RESULTS: Computational modeling demonstrates that acetylation of K124 causes tightening of the histone core and hinders accessibility to its C-terminus, which in turn diminishes CENP-C binding. Additionally, CENP-A K124ac/H4 K79ac containing nucleosomes are prone to DNA sliding. In vivo experiments using a CENP-A acetyl or unacetylatable mimic (K124Q and K124A, respectively) reveal alterations in CENP-C levels and a modest increase in mitotic errors. Furthermore, mutation of K124 results in alterations in centromeric replication timing. Purification of native CENP-A proteins followed by mass spectrometry analysis reveals that while CENP-A K124 is acetylated at G1/S, it switches to monomethylation during early S and mid-S phases. Finally, we provide evidence implicating the histone acetyltransferase (HAT) p300 in this cycle. CONCLUSIONS: Taken together, our data suggest that cyclical modifications within the CENP-A nucleosome contribute to the binding of key kinetochore proteins, the integrity of mitosis, and centromeric replication. These data support the paradigm that modifications in histone variants can influence key biological processes. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1186/s13072-017-0124-6) contains supplementary material, which is available to authorized users. BioMed Central 2017-04-04 /pmc/articles/PMC5379712/ /pubmed/28396698 http://dx.doi.org/10.1186/s13072-017-0124-6 Text en © The Author(s) 2017 Open AccessThis article is distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated.
spellingShingle Research
Bui, Minh
Pitman, Mary
Nuccio, Arthur
Roque, Serene
Donlin-Asp, Paul Gregory
Nita-Lazar, Aleksandra
Papoian, Garegin A.
Dalal, Yamini
Internal modifications in the CENP-A nucleosome modulate centromeric dynamics
title Internal modifications in the CENP-A nucleosome modulate centromeric dynamics
title_full Internal modifications in the CENP-A nucleosome modulate centromeric dynamics
title_fullStr Internal modifications in the CENP-A nucleosome modulate centromeric dynamics
title_full_unstemmed Internal modifications in the CENP-A nucleosome modulate centromeric dynamics
title_short Internal modifications in the CENP-A nucleosome modulate centromeric dynamics
title_sort internal modifications in the cenp-a nucleosome modulate centromeric dynamics
topic Research
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5379712/
https://www.ncbi.nlm.nih.gov/pubmed/28396698
http://dx.doi.org/10.1186/s13072-017-0124-6
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