Transcriptional supercoiling boosts topoisomerase II-mediated knotting of intracellular DNA
| Autor: | Ofelia Díaz-Ingelmo, Sílvia Dyson, Joana Segura, Cristian Micheletti, Antonio Valdés, Belén Martínez-García, Joaquim Roca, Lucia Coronel |
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| Přispěvatelé: | Ministerio de Economía y Competitividad (España), Ministero dell'Istruzione, dell'Università e della Ricerca |
| Jazyk: | angličtina |
| Rok vydání: | 2019 |
| Předmět: |
Saccharomyces cerevisiae Proteins
Transcription Genetic Type I Saccharomyces cerevisiae Type II Settore FIS/03 - Fisica della Materia chemistry.chemical_compound Prophase Genetic stomatognathic system Genetics Nucleosome Humans DNA Fungal Chromatin DNA Topoisomerases Type I DNA Topoisomerases Type II DNA Superhelical Nucleosomes Nucleic Acid Conformation biology Nucleic Acid Enzymes Topoisomerase DNA replication food and beverages DNA Cell biology Fungal surgical procedures operative chemistry biology.protein DNA supercoil Transcription DNA Topoisomerases Superhelical Intracellular |
| Zdroj: | Nucleic Acids Research Digital.CSIC. Repositorio Institucional del CSIC instname |
| ISSN: | 1362-4962 0305-1048 |
| Popis: | Recent studies have revealed that the DNA cross-inversion mechanism of topoisomerase II (topo II) not only removes DNA supercoils and DNA replication intertwines, but also produces small amounts of DNA knots within the clusters of nucleosomes that conform to eukaryotic chromatin. Here, we examine how transcriptional supercoiling of intracellular DNA affects the occurrence of these knots. We show that although (−) supercoiling does not change the basal DNA knotting probability, (+) supercoiling of DNA generated in front of the transcribing complexes increases DNA knot formation over 25-fold. The increase of topo II-mediated DNA knotting occurs both upon accumulation of (+) supercoiling in topoisomerase-deficient cells and during normal transcriptional supercoiling of DNA in TOP1 TOP2 cells. We also show that the high knotting probability (Pkn ≥ 0.5) of (+) supercoiled DNA reflects a 5-fold volume compaction of the nucleosomal fibers in vivo. Our findings indicate that topo II-mediated DNA knotting could be inherent to transcriptional supercoiling of DNA and other chromatin condensation processes and establish, therefore, a new crucial role of topoisomerase II in resetting the knotting–unknotting homeostasis of DNA during chromatin dynamics. Plan Estatal de Investigación Científica y Técnica of Spain [BFU2015-67007-P, MDM-2014-0435-02 to J.R., BES-2015-071597 to A.V.]; Italian Ministry of Education to C.M. Funding for open access charge: Plan Estatal de Investigación Científica y Técnica of Spain [BFU2015-67007-P]. |
| Databáze: | OpenAIRE |
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