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A Unified Linear Viscoelastic Model of the Cell Nucleus Defines the Mechanical Contributions of Lamins and Chromatin
The cell nucleus is constantly subjected to externally applied forces. During metazoan evolution, the nucleus has been optimized to allow physical deformability while protecting the genome under load. Aberrant nucleus mechanics can alter cell migration across narrow spaces in cancer metastasis and i...
Autores principales: | , , , , , , , |
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Formato: | Online Artículo Texto |
Lenguaje: | English |
Publicado: |
John Wiley and Sons Inc.
2020
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Materias: | |
Acceso en línea: | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7175345/ https://www.ncbi.nlm.nih.gov/pubmed/32328409 http://dx.doi.org/10.1002/advs.201901222 |
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author | Wintner, Oren Hirsch‐Attas, Nivi Schlossberg, Miriam Brofman, Fani Friedman, Roy Kupervaser, Meital Kitsberg, Danny Buxboim, Amnon |
author_facet | Wintner, Oren Hirsch‐Attas, Nivi Schlossberg, Miriam Brofman, Fani Friedman, Roy Kupervaser, Meital Kitsberg, Danny Buxboim, Amnon |
author_sort | Wintner, Oren |
collection | PubMed |
description | The cell nucleus is constantly subjected to externally applied forces. During metazoan evolution, the nucleus has been optimized to allow physical deformability while protecting the genome under load. Aberrant nucleus mechanics can alter cell migration across narrow spaces in cancer metastasis and immune response and disrupt nucleus mechanosensitivity. Uncovering the mechanical roles of lamins and chromatin is imperative for understanding the implications of physiological forces on cells and nuclei. Lamin‐knockout and ‐rescue fibroblasts and probed nucleus response to physiologically relevant stresses are generated. A minimal viscoelastic model is presented that captures dynamic resistance across different cell types, lamin composition, phosphorylation states, and chromatin condensation. The model is conserved at low and high loading and is validated by micropipette aspiration and nanoindentation rheology. A time scale emerges that separates between dominantly elastic and dominantly viscous regimes. While lamin‐A and lamin‐B1 contribute to nucleus stiffness, viscosity is specified mostly by lamin‐A. Elastic and viscous association of lamin‐B1 and lamin‐A is supported by transcriptional and proteomic profiling analyses. Chromatin decondensation quantified by electron microscopy softens the nucleus unless lamin‐A is expressed. A mechanical framework is provided for assessing nucleus response to applied forces in health and disease. |
format | Online Article Text |
id | pubmed-7175345 |
institution | National Center for Biotechnology Information |
language | English |
publishDate | 2020 |
publisher | John Wiley and Sons Inc. |
record_format | MEDLINE/PubMed |
spelling | pubmed-71753452020-04-23 A Unified Linear Viscoelastic Model of the Cell Nucleus Defines the Mechanical Contributions of Lamins and Chromatin Wintner, Oren Hirsch‐Attas, Nivi Schlossberg, Miriam Brofman, Fani Friedman, Roy Kupervaser, Meital Kitsberg, Danny Buxboim, Amnon Adv Sci (Weinh) Full Papers The cell nucleus is constantly subjected to externally applied forces. During metazoan evolution, the nucleus has been optimized to allow physical deformability while protecting the genome under load. Aberrant nucleus mechanics can alter cell migration across narrow spaces in cancer metastasis and immune response and disrupt nucleus mechanosensitivity. Uncovering the mechanical roles of lamins and chromatin is imperative for understanding the implications of physiological forces on cells and nuclei. Lamin‐knockout and ‐rescue fibroblasts and probed nucleus response to physiologically relevant stresses are generated. A minimal viscoelastic model is presented that captures dynamic resistance across different cell types, lamin composition, phosphorylation states, and chromatin condensation. The model is conserved at low and high loading and is validated by micropipette aspiration and nanoindentation rheology. A time scale emerges that separates between dominantly elastic and dominantly viscous regimes. While lamin‐A and lamin‐B1 contribute to nucleus stiffness, viscosity is specified mostly by lamin‐A. Elastic and viscous association of lamin‐B1 and lamin‐A is supported by transcriptional and proteomic profiling analyses. Chromatin decondensation quantified by electron microscopy softens the nucleus unless lamin‐A is expressed. A mechanical framework is provided for assessing nucleus response to applied forces in health and disease. John Wiley and Sons Inc. 2020-03-05 /pmc/articles/PMC7175345/ /pubmed/32328409 http://dx.doi.org/10.1002/advs.201901222 Text en © 2020 The Authors. Published by WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim This is an open access article under the terms of the http://creativecommons.org/licenses/by/4.0/ License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited. |
spellingShingle | Full Papers Wintner, Oren Hirsch‐Attas, Nivi Schlossberg, Miriam Brofman, Fani Friedman, Roy Kupervaser, Meital Kitsberg, Danny Buxboim, Amnon A Unified Linear Viscoelastic Model of the Cell Nucleus Defines the Mechanical Contributions of Lamins and Chromatin |
title | A Unified Linear Viscoelastic Model of the Cell Nucleus Defines the Mechanical Contributions of Lamins and Chromatin |
title_full | A Unified Linear Viscoelastic Model of the Cell Nucleus Defines the Mechanical Contributions of Lamins and Chromatin |
title_fullStr | A Unified Linear Viscoelastic Model of the Cell Nucleus Defines the Mechanical Contributions of Lamins and Chromatin |
title_full_unstemmed | A Unified Linear Viscoelastic Model of the Cell Nucleus Defines the Mechanical Contributions of Lamins and Chromatin |
title_short | A Unified Linear Viscoelastic Model of the Cell Nucleus Defines the Mechanical Contributions of Lamins and Chromatin |
title_sort | unified linear viscoelastic model of the cell nucleus defines the mechanical contributions of lamins and chromatin |
topic | Full Papers |
url | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7175345/ https://www.ncbi.nlm.nih.gov/pubmed/32328409 http://dx.doi.org/10.1002/advs.201901222 |
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