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Dynamics of human DNA topoisomerases IIα and IIβ in living cells

DNA topoisomerase (topo) II catalyses topological genomic changes essential for many DNA metabolic processes. It is also regarded as a structural component of the nuclear matrix in interphase and the mitotic chromosome scaffold. Mammals have two isoforms (α and β) with similar properties in vitro. H...

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Autores principales: Christensen, Morten O., Larsen, Morten K., Barthelmes, Hans Ullrich, Hock, Robert, Andersen, Claus L., Kjeldsen, Eigil, Knudsen, Birgitta R., Westergaard, Ole, Boege, Fritz, Mielke, Christian
Formato: Texto
Lenguaje:English
Publicado: The Rockefeller University Press 2002
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2173268/
https://www.ncbi.nlm.nih.gov/pubmed/11927602
http://dx.doi.org/10.1083/jcb.200112023
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author Christensen, Morten O.
Larsen, Morten K.
Barthelmes, Hans Ullrich
Hock, Robert
Andersen, Claus L.
Kjeldsen, Eigil
Knudsen, Birgitta R.
Westergaard, Ole
Boege, Fritz
Mielke, Christian
author_facet Christensen, Morten O.
Larsen, Morten K.
Barthelmes, Hans Ullrich
Hock, Robert
Andersen, Claus L.
Kjeldsen, Eigil
Knudsen, Birgitta R.
Westergaard, Ole
Boege, Fritz
Mielke, Christian
author_sort Christensen, Morten O.
collection PubMed
description DNA topoisomerase (topo) II catalyses topological genomic changes essential for many DNA metabolic processes. It is also regarded as a structural component of the nuclear matrix in interphase and the mitotic chromosome scaffold. Mammals have two isoforms (α and β) with similar properties in vitro. Here, we investigated their properties in living and proliferating cells, stably expressing biofluorescent chimera of the human isozymes. Topo IIα and IIβ behaved similarly in interphase but differently in mitosis, where only topo IIα was chromosome associated to a major part. During interphase, both isozymes joined in nucleolar reassembly and accumulated in nucleoli, which seemed not to involve catalytic DNA turnover because treatment with teniposide (stabilizing covalent catalytic DNA intermediates of topo II) relocated the bulk of the enzymes from the nucleoli to nucleoplasmic granules. Photobleaching revealed that the entire complement of both isozymes was completely mobile and free to exchange between nuclear subcompartments in interphase. In chromosomes, topo IIα was also completely mobile and had a uniform distribution. However, hypotonic cell lysis triggered an axial pattern. These observations suggest that topo II is not an immobile, structural component of the chromosomal scaffold or the interphase karyoskeleton, but rather a dynamic interaction partner of such structures.
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spelling pubmed-21732682008-05-01 Dynamics of human DNA topoisomerases IIα and IIβ in living cells Christensen, Morten O. Larsen, Morten K. Barthelmes, Hans Ullrich Hock, Robert Andersen, Claus L. Kjeldsen, Eigil Knudsen, Birgitta R. Westergaard, Ole Boege, Fritz Mielke, Christian J Cell Biol Article DNA topoisomerase (topo) II catalyses topological genomic changes essential for many DNA metabolic processes. It is also regarded as a structural component of the nuclear matrix in interphase and the mitotic chromosome scaffold. Mammals have two isoforms (α and β) with similar properties in vitro. Here, we investigated their properties in living and proliferating cells, stably expressing biofluorescent chimera of the human isozymes. Topo IIα and IIβ behaved similarly in interphase but differently in mitosis, where only topo IIα was chromosome associated to a major part. During interphase, both isozymes joined in nucleolar reassembly and accumulated in nucleoli, which seemed not to involve catalytic DNA turnover because treatment with teniposide (stabilizing covalent catalytic DNA intermediates of topo II) relocated the bulk of the enzymes from the nucleoli to nucleoplasmic granules. Photobleaching revealed that the entire complement of both isozymes was completely mobile and free to exchange between nuclear subcompartments in interphase. In chromosomes, topo IIα was also completely mobile and had a uniform distribution. However, hypotonic cell lysis triggered an axial pattern. These observations suggest that topo II is not an immobile, structural component of the chromosomal scaffold or the interphase karyoskeleton, but rather a dynamic interaction partner of such structures. The Rockefeller University Press 2002-04-01 /pmc/articles/PMC2173268/ /pubmed/11927602 http://dx.doi.org/10.1083/jcb.200112023 Text en Copyright © 2002, The Rockefeller University Press This article is distributed under the terms of an Attribution–Noncommercial–Share Alike–No Mirror Sites license for the first six months after the publication date (see http://www.rupress.org/terms). After six months it is available under a Creative Commons License (Attribution–Noncommercial–Share Alike 4.0 Unported license, as described at http://creativecommons.org/licenses/by-nc-sa/4.0/).
spellingShingle Article
Christensen, Morten O.
Larsen, Morten K.
Barthelmes, Hans Ullrich
Hock, Robert
Andersen, Claus L.
Kjeldsen, Eigil
Knudsen, Birgitta R.
Westergaard, Ole
Boege, Fritz
Mielke, Christian
Dynamics of human DNA topoisomerases IIα and IIβ in living cells
title Dynamics of human DNA topoisomerases IIα and IIβ in living cells
title_full Dynamics of human DNA topoisomerases IIα and IIβ in living cells
title_fullStr Dynamics of human DNA topoisomerases IIα and IIβ in living cells
title_full_unstemmed Dynamics of human DNA topoisomerases IIα and IIβ in living cells
title_short Dynamics of human DNA topoisomerases IIα and IIβ in living cells
title_sort dynamics of human dna topoisomerases iiα and iiβ in living cells
topic Article
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2173268/
https://www.ncbi.nlm.nih.gov/pubmed/11927602
http://dx.doi.org/10.1083/jcb.200112023
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