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Zahm JA, Harrison SC. A communication hub for phosphoregulation of kinetochore-microtubule attachment. Curr Biol 2024; 34:2308-2318.e6. [PMID: 38776904 DOI: 10.1016/j.cub.2024.04.067] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2023] [Revised: 04/06/2024] [Accepted: 04/29/2024] [Indexed: 05/25/2024]
Abstract
The Mps1 and Aurora B kinases regulate and monitor kinetochore attachment to spindle microtubules during cell division, ultimately ensuring accurate chromosome segregation. In yeast, the critical spindle attachment components are the Ndc80 and Dam1 complexes (Ndc80c and DASH/Dam1c, respectively). Ndc80c is a 600-Å-long heterotetramer that binds microtubules through a globular "head" at one end and centromere-proximal kinetochore components through a globular knob at the other end. Dam1c is a heterodecamer that forms a ring of 16-17 protomers around the shaft of the single kinetochore microtubule in point-centromere yeast. The ring coordinates the approximately eight Ndc80c rods per kinetochore. In published work, we showed that a site on the globular "head" of Ndc80c, including residues from both Ndc80 and Nuf2, binds a bipartite segment in the long C-terminal extension of Dam1. Results reported here show, both by in vitro binding experiments and by crystal structure determination, that the same site binds a conserved segment in the long N-terminal extension of Mps1. It also binds, less tightly, a conserved segment in the N-terminal extension of Ipl1 (yeast Aurora B). Together with results from experiments in yeast cells and from biochemical assays reported in two accompanying papers, the structures and graded affinities identify a communication hub for ensuring uniform bipolar attachment and for signaling anaphase onset.
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Affiliation(s)
- Jacob A Zahm
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA 02115, USA
| | - Stephen C Harrison
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA 02115, USA; Howard Hughes Medical Institute, Boston, MA 02115, USA.
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2
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Li S, Kasciukovic T, Tanaka TU. Kinetochore-microtubule error correction for biorientation: lessons from yeast. Biochem Soc Trans 2024; 52:29-39. [PMID: 38305688 PMCID: PMC10903472 DOI: 10.1042/bst20221261] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2023] [Revised: 01/11/2024] [Accepted: 01/15/2024] [Indexed: 02/03/2024]
Abstract
Accurate chromosome segregation in mitosis relies on sister kinetochores forming stable attachments to microtubules (MTs) extending from opposite spindle poles and establishing biorientation. To achieve this, erroneous kinetochore-MT interactions must be resolved through a process called error correction, which dissolves improper kinetochore-MT attachment and allows new interactions until biorientation is achieved. The Aurora B kinase plays key roles in driving error correction by phosphorylating Dam1 and Ndc80 complexes, while Mps1 kinase, Stu2 MT polymerase and phosphatases also regulate this process. Once biorientation is formed, tension is applied to kinetochore-MT interaction, stabilizing it. In this review article, we discuss the mechanisms of kinetochore-MT interaction, error correction and biorientation. We focus mainly on recent insights from budding yeast, where the attachment of a single MT to a single kinetochore during biorientation simplifies the analysis of error correction mechanisms.
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Affiliation(s)
- Shuyu Li
- Division of Molecular, Cell and Developmental Biology, School of Life Sciences, University of Dundee, Dow Street, Dundee DD1 5EH, U.K
| | - Taciana Kasciukovic
- Division of Molecular, Cell and Developmental Biology, School of Life Sciences, University of Dundee, Dow Street, Dundee DD1 5EH, U.K
| | - Tomoyuki U. Tanaka
- Division of Molecular, Cell and Developmental Biology, School of Life Sciences, University of Dundee, Dow Street, Dundee DD1 5EH, U.K
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3
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Muir KW, Batters C, Dendooven T, Yang J, Zhang Z, Burt A, Barford D. Structural mechanism of outer kinetochore Dam1-Ndc80 complex assembly on microtubules. Science 2023; 382:1184-1190. [PMID: 38060647 PMCID: PMC7615550 DOI: 10.1126/science.adj8736] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2023] [Accepted: 10/25/2023] [Indexed: 12/18/2023]
Abstract
Kinetochores couple chromosomes to the mitotic spindle to segregate the genome during cell division. An error correction mechanism drives the turnover of kinetochore-microtubule attachments until biorientation is achieved. The structural basis for how kinetochore-mediated chromosome segregation is accomplished and regulated remains an outstanding question. In this work, we describe the cryo-electron microscopy structure of the budding yeast outer kinetochore Ndc80 and Dam1 ring complexes assembled onto microtubules. Complex assembly occurs through multiple interfaces, and a staple within Dam1 aids ring assembly. Perturbation of key interfaces suppresses yeast viability. Force-rupture assays indicated that this is a consequence of impaired kinetochore-microtubule attachment. The presence of error correction phosphorylation sites at Ndc80-Dam1 ring complex interfaces and the Dam1 staple explains how kinetochore-microtubule attachments are destabilized and reset.
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Affiliation(s)
- Kyle W. Muir
- MRC Laboratory of Molecular Biology; Francis Crick Avenue, Cambridge, CB2 0QH, UK
| | - Christopher Batters
- MRC Laboratory of Molecular Biology; Francis Crick Avenue, Cambridge, CB2 0QH, UK
| | - Tom Dendooven
- MRC Laboratory of Molecular Biology; Francis Crick Avenue, Cambridge, CB2 0QH, UK
| | - Jing Yang
- MRC Laboratory of Molecular Biology; Francis Crick Avenue, Cambridge, CB2 0QH, UK
| | - Ziguo Zhang
- MRC Laboratory of Molecular Biology; Francis Crick Avenue, Cambridge, CB2 0QH, UK
| | - Alister Burt
- MRC Laboratory of Molecular Biology; Francis Crick Avenue, Cambridge, CB2 0QH, UK
| | - David Barford
- MRC Laboratory of Molecular Biology; Francis Crick Avenue, Cambridge, CB2 0QH, UK
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4
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Pandupuspitasari NS, Khan FA, Huang C, Ali A, Yousaf MR, Shakeel F, Putri EM, Negara W, Muktiani A, Prasetiyono BWHE, Kustiawan L, Wahyuni DS. Recent advances in chromosome capture techniques unraveling 3D genome architecture in germ cells, health, and disease. Funct Integr Genomics 2023; 23:214. [PMID: 37386239 DOI: 10.1007/s10142-023-01146-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2023] [Revised: 06/16/2023] [Accepted: 06/20/2023] [Indexed: 07/01/2023]
Abstract
In eukaryotes, the genome does not emerge in a specific shape but rather as a hierarchial bundle within the nucleus. This multifaceted genome organization consists of multiresolution cellular structures, such as chromosome territories, compartments, and topologically associating domains, which are frequently defined by architecture, design proteins including CTCF and cohesin, and chromatin loops. This review briefly discusses the advances in understanding the basic rules of control, chromatin folding, and functional areas in early embryogenesis. With the use of chromosome capture techniques, the latest advancements in technologies for visualizing chromatin interactions come close to revealing 3D genome formation frameworks with incredible detail throughout all genomic levels, including at single-cell resolution. The possibility of detecting variations in chromatin architecture might open up new opportunities for disease diagnosis and prevention, infertility treatments, therapeutic approaches, desired exploration, and many other application scenarios.
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Affiliation(s)
- Nuruliarizki Shinta Pandupuspitasari
- Laboratory of Animal Nutrition and Feed Science, Animal Science Department, Faculty of Animal and Agricultural Sciences, Universitas Diponegoro, Semarang, Indonesia.
| | - Faheem Ahmed Khan
- Research Center for Animal Husbandry, National Research and Innovation Agency, Bogor, Indonesia
| | - Chunjie Huang
- Institute of Reproductive Medicine, School of Medicine, Nantong University, Nantong, 226001, China
| | - Azhar Ali
- Laboratory of Molecular Biology and Genomics, Faculty of Science and Technology, University of Central Punjab, Lahore, Pakistan
| | - Muhammad Rizwan Yousaf
- Laboratory of Molecular Biology and Genomics, Faculty of Science and Technology, University of Central Punjab, Lahore, Pakistan
| | - Farwa Shakeel
- Laboratory of Molecular Biology and Genomics, Faculty of Science and Technology, University of Central Punjab, Lahore, Pakistan
| | - Ezi Masdia Putri
- Research Center for Animal Husbandry, National Research and Innovation Agency, Bogor, Indonesia
| | - Windu Negara
- Research Center for Animal Husbandry, National Research and Innovation Agency, Bogor, Indonesia
| | - Anis Muktiani
- Laboratory of Animal Nutrition and Feed Science, Animal Science Department, Faculty of Animal and Agricultural Sciences, Universitas Diponegoro, Semarang, Indonesia
| | - Bambang Waluyo Hadi Eko Prasetiyono
- Laboratory of Feed Technology, Animal Science Department, Faculty of Animal and Agricultural Sciences Universitas Diponegoro, Semarang, Indonesia
| | - Limbang Kustiawan
- Laboratory of Animal Nutrition and Feed Science, Animal Science Department, Faculty of Animal and Agricultural Sciences, Universitas Diponegoro, Semarang, Indonesia
| | - Dimar Sari Wahyuni
- Research Center for Animal Husbandry, National Research and Innovation Agency, Bogor, Indonesia
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Hinshaw SM, Quan Y, Cai J, Zhou AL, Zhou H. Multi-site phosphorylation of yeast Mif2/CENP-C promotes inner kinetochore assembly. Curr Biol 2023; 33:688-696.e6. [PMID: 36736323 PMCID: PMC9992315 DOI: 10.1016/j.cub.2023.01.012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2022] [Revised: 11/28/2022] [Accepted: 01/09/2023] [Indexed: 02/05/2023]
Abstract
Kinetochores control eukaryotic chromosome segregation by connecting chromosomal centromeres to spindle microtubules. Duplication of centromeric DNA necessitates kinetochore disassembly and subsequent reassembly on nascent sisters. To search for a regulatory mechanism that controls the earliest steps of this process, we studied Mif2/CENP-C, an essential basal component of the kinetochore. We found that phosphorylation of a central region of Mif2 (Mif2-PEST) enhances inner kinetochore assembly. Eliminating Mif2-PEST phosphorylation sites progressively impairs cellular fitness. The most severe Mif2-PEST mutations are lethal in cells lacking otherwise non-essential inner kinetochore factors. These data show that multi-site phosphorylation of Mif2/CENP-C controls inner kinetochore assembly.
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Affiliation(s)
- Stephen M Hinshaw
- Stanford Cancer Institute, Stanford School of Medicine, 1291 Welch Road, Stanford, CA 94305, USA.
| | - Yun Quan
- Department of Cellular and Molecular Medicine, University of California at San Diego, 9500 Gilman Drive, La Jolla, CA 92039, USA
| | - Jiaxi Cai
- Department of Cellular and Molecular Medicine, University of California at San Diego, 9500 Gilman Drive, La Jolla, CA 92039, USA
| | - Ann L Zhou
- Department of Cellular and Molecular Medicine, University of California at San Diego, 9500 Gilman Drive, La Jolla, CA 92039, USA
| | - Huilin Zhou
- Department of Cellular and Molecular Medicine, University of California at San Diego, 9500 Gilman Drive, La Jolla, CA 92039, USA.
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6
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Viñado AC, Calvo IA, Cenzano I, Olaverri D, Cocera M, San Martin-Uriz P, Romero JP, Vilas-Zornoza A, Vera L, Gomez-Cebrian N, Puchades-Carrasco L, Lisi-Vega LE, Apaolaza I, Valera P, Guruceaga E, Granero-Molto F, Ripalda-Cemborain P, Luck TJ, Bullinger L, Planes FJ, Rifon JJ, Méndez-Ferrer S, Yusuf RZ, Pardo-Saganta A, Prosper F, Saez B. The bone marrow niche regulates redox and energy balance in MLL::AF9 leukemia stem cells. Leukemia 2022; 36:1969-1979. [PMID: 35618797 PMCID: PMC7614282 DOI: 10.1038/s41375-022-01601-5] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2021] [Revised: 05/09/2022] [Accepted: 05/11/2022] [Indexed: 01/14/2023]
Abstract
Eradicating leukemia requires a deep understanding of the interaction between leukemic cells and their protective microenvironment. The CXCL12/CXCR4 axis has been postulated as a critical pathway dictating leukemia stem cell (LSC) chemoresistance in AML due to its role in controlling cellular egress from the marrow. Nevertheless, the cellular source of CXCL12 in the acute myeloid leukemia (AML) microenvironment and the mechanism by which CXCL12 exerts its protective role in vivo remain unresolved. Here, we show that CXCL12 produced by Prx1+ mesenchymal cells but not by mature osteolineage cells provide the necessary cues for the maintenance of LSCs in the marrow of an MLL::AF9-induced AML model. Prx1+ cells promote survival of LSCs by modulating energy metabolism and the REDOX balance in LSCs. Deletion of Cxcl12 leads to the accumulation of reactive oxygen species and DNA damage in LSCs, impairing their ability to perpetuate leukemia in transplantation experiments, a defect that can be attenuated by antioxidant therapy. Importantly, our data suggest that this phenomenon appears to be conserved in human patients. Hence, we have identified Prx1+ mesenchymal cells as an integral part of the complex niche-AML metabolic intertwining, pointing towards CXCL12/CXCR4 as a target to eradicate parenchymal LSCs in AML.
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Affiliation(s)
- Ana C Viñado
- Hematology-Oncology Program, CIMA Universidad de Navarra, Instituto de Investigación Sanitaria de Navarra (IdiSNA), 31008, Pamplona, Spain
- Centro de Investigación Biomédica en Red de Cáncer, CIBERONC, Madrid, Spain
| | - Isabel A Calvo
- Hematology-Oncology Program, CIMA Universidad de Navarra, Instituto de Investigación Sanitaria de Navarra (IdiSNA), 31008, Pamplona, Spain
- Centro de Investigación Biomédica en Red de Cáncer, CIBERONC, Madrid, Spain
| | - Itziar Cenzano
- Hematology-Oncology Program, CIMA Universidad de Navarra, Instituto de Investigación Sanitaria de Navarra (IdiSNA), 31008, Pamplona, Spain
| | - Danel Olaverri
- Tecnun Universidad de Navarra, School of Engineering, 20018, San Sebastian, Spain
| | - Miguel Cocera
- Hematology-Oncology Program, CIMA Universidad de Navarra, Instituto de Investigación Sanitaria de Navarra (IdiSNA), 31008, Pamplona, Spain
| | - Patxi San Martin-Uriz
- Hematology-Oncology Program, CIMA Universidad de Navarra, Instituto de Investigación Sanitaria de Navarra (IdiSNA), 31008, Pamplona, Spain
| | - Juan P Romero
- Hematology-Oncology Program, CIMA Universidad de Navarra, Instituto de Investigación Sanitaria de Navarra (IdiSNA), 31008, Pamplona, Spain
| | - Amaia Vilas-Zornoza
- Hematology-Oncology Program, CIMA Universidad de Navarra, Instituto de Investigación Sanitaria de Navarra (IdiSNA), 31008, Pamplona, Spain
| | - Laura Vera
- Regenerative Medicine Program, CIMA Universidad de Navarra, Instituto de Investigación Sanitaria de Navarra (IdiSNA), 31008, Pamplona, Spain
| | - Nuria Gomez-Cebrian
- Drug Discovery Unit, Instituto de Investigación Sanitaria La Fe, 46026, Valencia, Spain
| | | | - Livia E Lisi-Vega
- Wellcome-MRC Cambridge Stem Cell Institute, Department of Hematology, University of Cambridge, and NHS Blood and Transplant, Cambridge, CB2 0AW, UK
| | - Iñigo Apaolaza
- Tecnun Universidad de Navarra, School of Engineering, 20018, San Sebastian, Spain
- Universidad de Navarra, Centro de Ingeniería Biomédica and DATAI Instituto de Ciencia de los Datos e Inteligencia Artificial, 31008, Pamplona, Spain
| | - Pablo Valera
- Hematology-Oncology Program, CIMA Universidad de Navarra, Instituto de Investigación Sanitaria de Navarra (IdiSNA), 31008, Pamplona, Spain
| | - Elisabeth Guruceaga
- Hematology-Oncology Program, CIMA Universidad de Navarra, Instituto de Investigación Sanitaria de Navarra (IdiSNA), 31008, Pamplona, Spain
| | - Froilan Granero-Molto
- Regenerative Medicine Program, CIMA Universidad de Navarra, Instituto de Investigación Sanitaria de Navarra (IdiSNA), 31008, Pamplona, Spain
- Cell Therapy Area, Clínica Universidad de Navarra, 31008, Pamplona, Spain
- Department of Orthopaedic Surgery and Traumatology, Clínica Universidad de Navarra, 31008, Pamplona, Spain
| | - Purificacion Ripalda-Cemborain
- Regenerative Medicine Program, CIMA Universidad de Navarra, Instituto de Investigación Sanitaria de Navarra (IdiSNA), 31008, Pamplona, Spain
- Department of Orthopaedic Surgery and Traumatology, Clínica Universidad de Navarra, 31008, Pamplona, Spain
| | - Tamara J Luck
- Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Department of Hematology, Oncology, and Cancer Immunology, Berlin, Germany
- German Cancer Consortium (DKTK) and German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - Lars Bullinger
- Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Department of Hematology, Oncology, and Cancer Immunology, Berlin, Germany
- German Cancer Consortium (DKTK) and German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - Francisco J Planes
- Tecnun Universidad de Navarra, School of Engineering, 20018, San Sebastian, Spain
- Universidad de Navarra, Centro de Ingeniería Biomédica and DATAI Instituto de Ciencia de los Datos e Inteligencia Artificial, 31008, Pamplona, Spain
| | - José J Rifon
- Department of Hematology, Cell Therapy and Center of Cancer of the University of Navarra, Clínica Universidad de Navarra (CCUN), 31008, Pamplona, Spain
| | - Simón Méndez-Ferrer
- Wellcome-MRC Cambridge Stem Cell Institute, Department of Hematology, University of Cambridge, and NHS Blood and Transplant, Cambridge, CB2 0AW, UK
| | - Rushdia Z Yusuf
- Dana Farber Cancer Institute, 450 Brookline Ave, Boston, MA, 02215, USA
| | - Ana Pardo-Saganta
- Institute for Lung Health (ILH), Justus Liebig University Giessen, Giessen, 35392, Germany
- Universities of Giessen and Marburg Lung Center (UGMLC), Giessen, 35392, Germany
- German Center for Lung Research (DZL), Giessen, 35392, Germany
| | - Felipe Prosper
- Hematology-Oncology Program, CIMA Universidad de Navarra, Instituto de Investigación Sanitaria de Navarra (IdiSNA), 31008, Pamplona, Spain
- Centro de Investigación Biomédica en Red de Cáncer, CIBERONC, Madrid, Spain
- Department of Hematology, Cell Therapy and Center of Cancer of the University of Navarra, Clínica Universidad de Navarra (CCUN), 31008, Pamplona, Spain
| | - Borja Saez
- Hematology-Oncology Program, CIMA Universidad de Navarra, Instituto de Investigación Sanitaria de Navarra (IdiSNA), 31008, Pamplona, Spain.
- Centro de Investigación Biomédica en Red de Cáncer, CIBERONC, Madrid, Spain.
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Yeast Kinesin-5 Motor Protein CIN8 Promotes Accurate Chromosome Segregation. Cells 2022; 11:cells11142144. [PMID: 35883587 PMCID: PMC9316075 DOI: 10.3390/cells11142144] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2022] [Revised: 06/15/2022] [Accepted: 07/04/2022] [Indexed: 11/17/2022] Open
Abstract
Accurate chromosome segregation depends on bipolar chromosome–microtubule attachment and tension generation on chromosomes. Incorrect chromosome attachment results in chromosome missegregation, which contributes to genome instability. The kinetochore is a protein complex that localizes at the centromere region of a chromosome and mediates chromosome–microtubule interaction. Incorrect chromosome attachment leads to checkpoint activation to prevent anaphase onset. Kinetochore detachment activates the spindle assembly checkpoint (SAC), while tensionless kinetochore attachment relies on both the SAC and tension checkpoint. In budding yeast Saccharomyces cerevisiae, kinesin-5 motor proteins Cin8 and Kip1 are needed to separate spindle pole bodies for spindle assembly, and deletion of CIN8 causes lethality in the absence of SAC. To study the function of Cin8 and Kip1 in chromosome segregation, we constructed an auxin-inducible degron (AID) mutant, cin8-AID. With this conditional mutant, we first confirmed that cin8-AID kip1∆ double mutants were lethal when Cin8 is depleted in the presence of auxin. These cells arrested in metaphase with unseparated spindle pole bodies and kinetochores. We further showed that the absence of either the SAC or tension checkpoint was sufficient to abolish the cell-cycle delay in cin8-AID mutants, causing chromosome missegregation and viability loss. The tension checkpoint-dependent phenotype in cells with depleted Cin8 suggests the presence of tensionless chromosome attachment. We speculate that the failed spindle pole body separation in cin8 mutants could increase the chance of tensionless syntelic chromosome attachments, which depends on functional tension checkpoint for survival.
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SWAP, SWITCH, and STABILIZE: Mechanisms of Kinetochore–Microtubule Error Correction. Cells 2022; 11:cells11091462. [PMID: 35563768 PMCID: PMC9104000 DOI: 10.3390/cells11091462] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2022] [Revised: 04/20/2022] [Accepted: 04/21/2022] [Indexed: 11/17/2022] Open
Abstract
For correct chromosome segregation in mitosis, eukaryotic cells must establish chromosome biorientation where sister kinetochores attach to microtubules extending from opposite spindle poles. To establish biorientation, any aberrant kinetochore–microtubule interactions must be resolved in the process called error correction. For resolution of the aberrant interactions in error correction, kinetochore–microtubule interactions must be exchanged until biorientation is formed (the SWAP process). At initiation of biorientation, the state of weak kinetochore–microtubule interactions should be converted to the state of stable interactions (the SWITCH process)—the conundrum of this conversion is called the initiation problem of biorientation. Once biorientation is established, tension is applied on kinetochore–microtubule interactions, which stabilizes the interactions (the STABILIZE process). Aurora B kinase plays central roles in promoting error correction, and Mps1 kinase and Stu2 microtubule polymerase also play important roles. In this article, we review mechanisms of error correction by considering the SWAP, SWITCH, and STABILIZE processes. We mainly focus on mechanisms found in budding yeast, where only one microtubule attaches to a single kinetochore at biorientation, making the error correction mechanisms relatively simpler.
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de Regt AK, Clark CJ, Asbury CL, Biggins S. Tension can directly suppress Aurora B kinase-triggered release of kinetochore-microtubule attachments. Nat Commun 2022; 13:2152. [PMID: 35443757 PMCID: PMC9021268 DOI: 10.1038/s41467-022-29542-8] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2018] [Accepted: 03/03/2022] [Indexed: 11/09/2022] Open
Abstract
Chromosome segregation requires sister kinetochores to attach microtubules emanating from opposite spindle poles. Proper attachments come under tension and are stabilized, but defective attachments lacking tension are released, giving another chance for correct attachments to form. This error correction process depends on Aurora B kinase, which phosphorylates kinetochores to destabilize their microtubule attachments. However, the mechanism by which Aurora B distinguishes tense versus relaxed kinetochores remains unclear because it is difficult to detect kinase-triggered detachment and to manipulate kinetochore tension in vivo. To address these challenges, we apply an optical trapping-based assay using soluble Aurora B and reconstituted kinetochore-microtubule attachments. Strikingly, the tension on these attachments suppresses their Aurora B-triggered release, suggesting that tension-dependent changes in the conformation of kinetochores can regulate Aurora B activity or its outcome. Our work uncovers the basis for a key mechano-regulatory event that ensures accurate segregation and may inform studies of other mechanically regulated enzymes.
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Affiliation(s)
- Anna K de Regt
- Howard Hughes Medical Institute, Division of Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, WA, USA
| | - Cordell J Clark
- Howard Hughes Medical Institute, Division of Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, WA, USA
| | - Charles L Asbury
- Department of Physiology and Biophysics, University of Washington, Seattle, WA, USA.
| | - Sue Biggins
- Howard Hughes Medical Institute, Division of Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, WA, USA.
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10
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Doodhi H, Tanaka TU. Swap and stop - Kinetochores play error correction with microtubules: Mechanisms of kinetochore-microtubule error correction: Mechanisms of kinetochore-microtubule error correction. Bioessays 2022; 44:e2100246. [PMID: 35261042 PMCID: PMC9344824 DOI: 10.1002/bies.202100246] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2021] [Revised: 02/23/2022] [Accepted: 02/25/2022] [Indexed: 12/30/2022]
Abstract
Correct chromosome segregation in mitosis relies on chromosome biorientation, in which sister kinetochores attach to microtubules from opposite spindle poles prior to segregation. To establish biorientation, aberrant kinetochore–microtubule interactions must be resolved through the error correction process. During error correction, kinetochore–microtubule interactions are exchanged (swapped) if aberrant, but the exchange must stop when biorientation is established. In this article, we discuss recent findings in budding yeast, which have revealed fundamental molecular mechanisms promoting this “swap and stop” process for error correction. Where relevant, we also compare the findings in budding yeast with mechanisms in higher eukaryotes. Evidence suggests that Aurora B kinase differentially regulates kinetochore attachments to the microtubule end and its lateral side and switches relative strength of the two kinetochore–microtubule attachment modes, which drives the exchange of kinetochore–microtubule interactions to resolve aberrant interactions. However, Aurora B kinase, recruited to centromeres and inner kinetochores, cannot reach its targets at kinetochore–microtubule interface when tension causes kinetochore stretching, which stops the kinetochore–microtubule exchange once biorientation is established.
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Affiliation(s)
- Harinath Doodhi
- Centre for Gene Regulation and Expression, School of Life Sciences, University of Dundee, Dundee, UK
| | - Tomoyuki U Tanaka
- Centre for Gene Regulation and Expression, School of Life Sciences, University of Dundee, Dundee, UK
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11
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Abstract
The centromere serves as the binding site for the kinetochore and is essential for the faithful segregation of chromosomes throughout cell division. The point centromere in yeast is encoded by a ∼115 bp specific DNA sequence, whereas regional centromeres range from 6-10 kbp in fission yeast to 5-10 Mbp in humans. Understanding the physical structure of centromere chromatin (pericentromere in yeast), defined as the chromatin between sister kinetochores, will provide fundamental insights into how centromere DNA is woven into a stiff spring that is able to resist microtubule pulling forces during mitosis. One hallmark of the pericentromere is the enrichment of the structural maintenance of chromosome (SMC) proteins cohesin and condensin. Based on studies from population approaches (ChIP-seq and Hi-C) and experimentally obtained images of fluorescent probes of pericentromeric structure, as well as quantitative comparisons between simulations and experimental results, we suggest a mechanism for building tension between sister kinetochores. We propose that the centromere is a chromatin bottlebrush that is organized by the loop-extruding proteins condensin and cohesin. The bottlebrush arrangement provides a biophysical means to transform pericentromeric chromatin into a spring due to the steric repulsion between radial loops. We argue that the bottlebrush is an organizing principle for chromosome organization that has emerged from multiple approaches in the field.
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12
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Sarangapani KK, Koch LB, Nelson CR, Asbury CL, Biggins S. Kinetochore-bound Mps1 regulates kinetochore-microtubule attachments via Ndc80 phosphorylation. J Cell Biol 2021; 220:e202106130. [PMID: 34647959 PMCID: PMC8641409 DOI: 10.1083/jcb.202106130] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2021] [Revised: 08/03/2021] [Accepted: 09/09/2021] [Indexed: 12/22/2022] Open
Abstract
Dividing cells detect and correct erroneous kinetochore-microtubule attachments during mitosis, thereby avoiding chromosome missegregation. The Aurora B kinase phosphorylates microtubule-binding elements specifically at incorrectly attached kinetochores, promoting their release and providing another chance for proper attachments to form. However, growing evidence suggests that the Mps1 kinase is also required for error correction. Here we directly examine how Mps1 activity affects kinetochore-microtubule attachments using a reconstitution-based approach that allows us to separate its effects from Aurora B activity. When endogenous Mps1 that copurifies with kinetochores is activated in vitro, it weakens their attachments to microtubules via phosphorylation of Ndc80, a major microtubule-binding protein. This phosphorylation contributes to error correction because phospho-deficient Ndc80 mutants exhibit genetic interactions and segregation defects when combined with mutants in other error correction pathways. In addition, Mps1 phosphorylation of Ndc80 is stimulated on kinetochores lacking tension. These data suggest that Mps1 provides an additional mechanism for correcting erroneous kinetochore-microtubule attachments, complementing the well-known activity of Aurora B.
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Affiliation(s)
| | - Lori B. Koch
- Howard Hughes Medical Institute, Chevy Chase, MD
- Division of Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, WA
- Molecular and Cellular Biology Program, University of Washington, Seattle, WA
| | - Christian R. Nelson
- Howard Hughes Medical Institute, Chevy Chase, MD
- Division of Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, WA
| | - Charles L. Asbury
- Department of Physiology & Biophysics, University of Washington, Seattle, WA
| | - Sue Biggins
- Howard Hughes Medical Institute, Chevy Chase, MD
- Division of Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, WA
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13
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He Y, Lawrimore J, Cook D, Van Gorder EE, De Larimat SC, Adalsteinsson D, Forest MG, Bloom K. Statistical mechanics of chromosomes: in vivo and in silico approaches reveal high-level organization and structure arise exclusively through mechanical feedback between loop extruders and chromatin substrate properties. Nucleic Acids Res 2020; 48:11284-11303. [PMID: 33080019 PMCID: PMC7672462 DOI: 10.1093/nar/gkaa871] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2020] [Revised: 09/22/2020] [Accepted: 09/24/2020] [Indexed: 11/14/2022] Open
Abstract
The revolution in understanding higher order chromosome dynamics and organization derives from treating the chromosome as a chain polymer and adapting appropriate polymer-based physical principles. Using basic principles, such as entropic fluctuations and timescales of relaxation of Rouse polymer chains, one can recapitulate the dominant features of chromatin motion observed in vivo. An emerging challenge is to relate the mechanical properties of chromatin to more nuanced organizational principles such as ubiquitous DNA loops. Toward this goal, we introduce a real-time numerical simulation model of a long chain polymer in the presence of histones and condensin, encoding physical principles of chromosome dynamics with coupled histone and condensin sources of transient loop generation. An exact experimental correlate of the model was obtained through analysis of a model-matching fluorescently labeled circular chromosome in live yeast cells. We show that experimentally observed chromosome compaction and variance in compaction are reproduced only with tandem interactions between histone and condensin, not from either individually. The hierarchical loop structures that emerge upon incorporation of histone and condensin activities significantly impact the dynamic and structural properties of chromatin. Moreover, simulations reveal that tandem condensin–histone activity is responsible for higher order chromosomal structures, including recently observed Z-loops.
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Affiliation(s)
- Yunyan He
- Department of Mathematics, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Josh Lawrimore
- Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Diana Cook
- Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | | | | | - David Adalsteinsson
- Department of Mathematics, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - M Gregory Forest
- Department of Mathematics, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA.,Department of Applied Physical Sciences, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Kerry Bloom
- Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
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14
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Abstract
Until recently, our understanding of chromosome organization in higher eukaryotic cells has been based on analyses of large-scale, low-resolution changes in chromosomes structure. More recently, CRISPR-Cas9 technologies have allowed us to "zoom in" and visualize specific chromosome regions in live cells so that we can begin to examine in detail the dynamics of chromosome organization in individual cells. In this review, we discuss traditional methods of chromosome locus visualization and look at how CRISPR-Cas9 gene-targeting methodologies have helped improve their application. We also describe recent developments of the CRISPR-Cas9 technology that enable visualization of specific chromosome regions without the requirement for complex genetic manipulation.
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Affiliation(s)
- John K Eykelenboom
- Centre for Gene Regulation and Expression, School of Life Sciences, University of Dundee , Dundee, UK
| | - Tomoyuki U Tanaka
- Centre for Gene Regulation and Expression, School of Life Sciences, University of Dundee , Dundee, UK
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15
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Lawrimore CJ, Bloom K. Common Features of the Pericentromere and Nucleolus. Genes (Basel) 2019; 10:E1029. [PMID: 31835574 PMCID: PMC6947172 DOI: 10.3390/genes10121029] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2019] [Revised: 12/05/2019] [Accepted: 12/07/2019] [Indexed: 12/20/2022] Open
Abstract
Both the pericentromere and the nucleolus have unique characteristics that distinguish them amongst the rest of genome. Looping of pericentromeric DNA, due to structural maintenance of chromosome (SMC) proteins condensin and cohesin, drives its ability to maintain tension during metaphase. Similar loops are formed via condensin and cohesin in nucleolar ribosomal DNA (rDNA). Condensin and cohesin are also concentrated in transfer RNA (tRNA) genes, genes which may be located within the pericentromere as well as tethered to the nucleolus. Replication fork stalling, as well as downstream consequences such as genomic recombination, are characteristic of both the pericentromere and rDNA. Furthermore, emerging evidence suggests that the pericentromere may function as a liquid-liquid phase separated domain, similar to the nucleolus. We therefore propose that the pericentromere and nucleolus, in part due to their enrichment of SMC proteins and others, contain similar domains that drive important cellular activities such as segregation, stability, and repair.
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Affiliation(s)
| | - Kerry Bloom
- Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599-3280, USA;
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16
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Relax, Kinetochores Are Exquisitely Sensitive to Tension. Dev Cell 2019; 49:5-7. [PMID: 30965035 DOI: 10.1016/j.devcel.2019.03.019] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
By estimating the absolute levels of tension at kinetochores in dividing yeast cells and relating these measurements to kinetochore detachment probability, Mukherjee et al. (2019) quantify in this issue of Developmental Cell the force sensitivity of the mitotic error correction system.
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17
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Lawrimore J, Bloom K. The regulation of chromosome segregation via centromere loops. Crit Rev Biochem Mol Biol 2019; 54:352-370. [PMID: 31573359 PMCID: PMC6856439 DOI: 10.1080/10409238.2019.1670130] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2019] [Revised: 09/02/2019] [Accepted: 09/17/2019] [Indexed: 12/14/2022]
Abstract
Biophysical studies of the yeast centromere have shown that the organization of the centromeric chromatin plays a crucial role in maintaining proper tension between sister kinetochores during mitosis. While centromeric chromatin has traditionally been considered a simple spring, recent work reveals the centromere as a multifaceted, tunable shock absorber. Centromeres can differ from other regions of the genome in their heterochromatin state, supercoiling state, and enrichment of structural maintenance of chromosomes (SMC) protein complexes. Each of these differences can be utilized to alter the effective stiffness of centromeric chromatin. In budding yeast, the SMC protein complexes condensin and cohesin stiffen chromatin by forming and cross-linking chromatin loops, respectively, into a fibrous structure resembling a bottlebrush. The high density of the loops compacts chromatin while spatially isolating the tension from spindle pulling forces to a subset of the chromatin. Paradoxically, the molecular crowding of chromatin via cohesin and condensin also causes an outward/poleward force. The structure allows the centromere to act as a shock absorber that buffers the variable forces generated by dynamic spindle microtubules. Based on the distribution of SMCs from bacteria to human and the conserved distance between sister kinetochores in a wide variety of organisms (0.4 to 1 micron), we propose that the bottlebrush mechanism is the foundational principle for centromere function in eukaryotes.
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Affiliation(s)
- Josh Lawrimore
- Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Kerry Bloom
- Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
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18
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Lawrimore J, Doshi A, Friedman B, Yeh E, Bloom K. Geometric partitioning of cohesin and condensin is a consequence of chromatin loops. Mol Biol Cell 2018; 29:2737-2750. [PMID: 30207827 PMCID: PMC6249845 DOI: 10.1091/mbc.e18-02-0131] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2018] [Revised: 08/13/2018] [Accepted: 09/04/2018] [Indexed: 12/29/2022] Open
Abstract
SMC (structural maintenance of chromosomes) complexes condensin and cohesin are crucial for proper chromosome organization. Condensin has been reported to be a mechanochemical motor capable of forming chromatin loops, while cohesin passively diffuses along chromatin to tether sister chromatids. In budding yeast, the pericentric region is enriched in both condensin and cohesin. As in higher-eukaryotic chromosomes, condensin is localized to the axial chromatin of the pericentric region, while cohesin is enriched in the radial chromatin. Thus, the pericentric region serves as an ideal model for deducing the role of SMC complexes in chromosome organization. We find condensin-mediated chromatin loops establish a robust chromatin organization, while cohesin limits the area that chromatin loops can explore. Upon biorientation, extensional force from the mitotic spindle aggregates condensin-bound chromatin from its equilibrium position to the axial core of pericentric chromatin, resulting in amplified axial tension. The axial localization of condensin depends on condensin's ability to bind to chromatin to form loops, while the radial localization of cohesin depends on cohesin's ability to diffuse along chromatin. The different chromatin-tethering modalities of condensin and cohesin result in their geometric partitioning in the presence of an extensional force on chromatin.
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Affiliation(s)
- Josh Lawrimore
- Curriculum in Genetics and Molecular Biology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599
- Biology Department, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599
| | - Ayush Doshi
- Biology Department, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599
| | - Brandon Friedman
- Biology Department, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599
| | - Elaine Yeh
- Biology Department, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599
| | - Kerry Bloom
- Biology Department, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599
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19
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Ivanov MP, Ladurner R, Poser I, Beveridge R, Rampler E, Hudecz O, Novatchkova M, Hériché JK, Wutz G, van der Lelij P, Kreidl E, Hutchins JR, Axelsson-Ekker H, Ellenberg J, Hyman AA, Mechtler K, Peters JM. The replicative helicase MCM recruits cohesin acetyltransferase ESCO2 to mediate centromeric sister chromatid cohesion. EMBO J 2018; 37:e97150. [PMID: 29930102 PMCID: PMC6068434 DOI: 10.15252/embj.201797150] [Citation(s) in RCA: 38] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2017] [Revised: 02/27/2018] [Accepted: 04/09/2018] [Indexed: 11/09/2022] Open
Abstract
Chromosome segregation depends on sister chromatid cohesion which is established by cohesin during DNA replication. Cohesive cohesin complexes become acetylated to prevent their precocious release by WAPL before cells have reached mitosis. To obtain insight into how DNA replication, cohesion establishment and cohesin acetylation are coordinated, we analysed the interaction partners of 55 human proteins implicated in these processes by mass spectrometry. This proteomic screen revealed that on chromatin the cohesin acetyltransferase ESCO2 associates with the MCM2-7 subcomplex of the replicative Cdc45-MCM-GINS helicase. The analysis of ESCO2 mutants defective in MCM binding indicates that these interactions are required for proper recruitment of ESCO2 to chromatin, cohesin acetylation during DNA replication, and centromeric cohesion. We propose that MCM binding enables ESCO2 to travel with replisomes to acetylate cohesive cohesin complexes in the vicinity of replication forks so that these complexes can be protected from precocious release by WAPL Our results also indicate that ESCO1 and ESCO2 have distinct functions in maintaining cohesion between chromosome arms and centromeres, respectively.
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Affiliation(s)
| | - Rene Ladurner
- Research Institute of Molecular Pathology, Vienna, Austria
| | - Ina Poser
- Max Planck Institute of Molecular Cell Biology and Genetics, Dresden, Germany
| | | | - Evelyn Rampler
- Research Institute of Molecular Pathology, Vienna, Austria
| | - Otto Hudecz
- Institute of Molecular Biotechnology, Vienna, Austria
| | | | | | - Gordana Wutz
- Research Institute of Molecular Pathology, Vienna, Austria
| | | | - Emanuel Kreidl
- Research Institute of Molecular Pathology, Vienna, Austria
| | | | | | - Jan Ellenberg
- European Molecular Biology Laboratory, Heidelberg, Germany
| | - Anthony A Hyman
- Max Planck Institute of Molecular Cell Biology and Genetics, Dresden, Germany
| | - Karl Mechtler
- Research Institute of Molecular Pathology, Vienna, Austria
- Institute of Molecular Biotechnology, Vienna, Austria
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20
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Piskadlo E, Oliveira RA. A Topology-Centric View on Mitotic Chromosome Architecture. Int J Mol Sci 2017; 18:E2751. [PMID: 29258269 PMCID: PMC5751350 DOI: 10.3390/ijms18122751] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2017] [Revised: 12/14/2017] [Accepted: 12/15/2017] [Indexed: 02/04/2023] Open
Abstract
Mitotic chromosomes are long-known structures, but their internal organization and the exact process by which they are assembled are still a great mystery in biology. Topoisomerase II is crucial for various aspects of mitotic chromosome organization. The unique ability of this enzyme to untangle topologically intertwined DNA molecules (catenations) is of utmost importance for the resolution of sister chromatid intertwines. Although still controversial, topoisomerase II has also been proposed to directly contribute to chromosome compaction, possibly by promoting chromosome self-entanglements. These two functions raise a strong directionality issue towards topoisomerase II reactions that are able to disentangle sister DNA molecules (in trans) while compacting the same DNA molecule (in cis). Here, we review the current knowledge on topoisomerase II role specifically during mitosis, and the mechanisms that directly or indirectly regulate its activity to ensure faithful chromosome segregation. In particular, we discuss how the activity or directionality of this enzyme could be regulated by the SMC (structural maintenance of chromosomes) complexes, predominantly cohesin and condensin, throughout mitosis.
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Affiliation(s)
- Ewa Piskadlo
- Instituto Gulbenkian de Ciência, Rua da Quinta Grande 6, 2780-156 Oeiras, Portugal.
| | - Raquel A Oliveira
- Instituto Gulbenkian de Ciência, Rua da Quinta Grande 6, 2780-156 Oeiras, Portugal.
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21
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Wutz G, Várnai C, Nagasaka K, Cisneros DA, Stocsits RR, Tang W, Schoenfelder S, Jessberger G, Muhar M, Hossain MJ, Walther N, Koch B, Kueblbeck M, Ellenberg J, Zuber J, Fraser P, Peters JM. Topologically associating domains and chromatin loops depend on cohesin and are regulated by CTCF, WAPL, and PDS5 proteins. EMBO J 2017; 36:3573-3599. [PMID: 29217591 PMCID: PMC5730888 DOI: 10.15252/embj.201798004] [Citation(s) in RCA: 471] [Impact Index Per Article: 67.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2017] [Revised: 11/07/2017] [Accepted: 11/07/2017] [Indexed: 01/05/2023] Open
Abstract
Mammalian genomes are spatially organized into compartments, topologically associating domains (TADs), and loops to facilitate gene regulation and other chromosomal functions. How compartments, TADs, and loops are generated is unknown. It has been proposed that cohesin forms TADs and loops by extruding chromatin loops until it encounters CTCF, but direct evidence for this hypothesis is missing. Here, we show that cohesin suppresses compartments but is required for TADs and loops, that CTCF defines their boundaries, and that the cohesin unloading factor WAPL and its PDS5 binding partners control the length of loops. In the absence of WAPL and PDS5 proteins, cohesin forms extended loops, presumably by passing CTCF sites, accumulates in axial chromosomal positions (vermicelli), and condenses chromosomes. Unexpectedly, PDS5 proteins are also required for boundary function. These results show that cohesin has an essential genome-wide function in mediating long-range chromatin interactions and support the hypothesis that cohesin creates these by loop extrusion, until it is delayed by CTCF in a manner dependent on PDS5 proteins, or until it is released from DNA by WAPL.
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Affiliation(s)
- Gordana Wutz
- Research Institute of Molecular Pathology (IMP), Vienna Biocenter (VBC), Vienna, Austria
| | - Csilla Várnai
- Nuclear Dynamics Programme, The Babraham Institute, Babraham Research Campus, Cambridge, UK
| | - Kota Nagasaka
- Research Institute of Molecular Pathology (IMP), Vienna Biocenter (VBC), Vienna, Austria
| | - David A Cisneros
- Research Institute of Molecular Pathology (IMP), Vienna Biocenter (VBC), Vienna, Austria
| | - Roman R Stocsits
- Research Institute of Molecular Pathology (IMP), Vienna Biocenter (VBC), Vienna, Austria
| | - Wen Tang
- Research Institute of Molecular Pathology (IMP), Vienna Biocenter (VBC), Vienna, Austria
| | - Stefan Schoenfelder
- Nuclear Dynamics Programme, The Babraham Institute, Babraham Research Campus, Cambridge, UK
| | - Gregor Jessberger
- Research Institute of Molecular Pathology (IMP), Vienna Biocenter (VBC), Vienna, Austria
| | - Matthias Muhar
- Research Institute of Molecular Pathology (IMP), Vienna Biocenter (VBC), Vienna, Austria
| | - M Julius Hossain
- Cell Biology and Biophysics Unit, European Molecular Biology Laboratory, Heidelberg, Germany
| | - Nike Walther
- Cell Biology and Biophysics Unit, European Molecular Biology Laboratory, Heidelberg, Germany
| | - Birgit Koch
- Cell Biology and Biophysics Unit, European Molecular Biology Laboratory, Heidelberg, Germany
| | - Moritz Kueblbeck
- Cell Biology and Biophysics Unit, European Molecular Biology Laboratory, Heidelberg, Germany
| | - Jan Ellenberg
- Cell Biology and Biophysics Unit, European Molecular Biology Laboratory, Heidelberg, Germany
| | - Johannes Zuber
- Research Institute of Molecular Pathology (IMP), Vienna Biocenter (VBC), Vienna, Austria
| | - Peter Fraser
- Nuclear Dynamics Programme, The Babraham Institute, Babraham Research Campus, Cambridge, UK
- Department of Biological Science, Florida State University, Tallahassee, FL, USA
| | - Jan-Michael Peters
- Research Institute of Molecular Pathology (IMP), Vienna Biocenter (VBC), Vienna, Austria
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22
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Rad52 phosphorylation by Ipl1 and Mps1 contributes to Mps1 kinetochore localization and spindle assembly checkpoint regulation. Proc Natl Acad Sci U S A 2017; 114:E9261-E9270. [PMID: 29078282 DOI: 10.1073/pnas.1705261114] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Rad52 is well known as a key factor in homologous recombination. Here, we report that Rad52 has functions unrelated to homologous recombination in Saccharomyces cerevisiae; it plays a role in the recruitment of Mps1 to the kinetochores and the maintenance of spindle assembly checkpoint (SAC) activity. Deletion of RAD52 causes various phenotypes related to the dysregulation of chromosome biorientation. Rad52 directly affects efficient operation of the SAC and accurate chromosome segregation. Remarkably, by using an in vitro kinase assay, we found that Rad52 is a substrate of Ipl1/Aurora and Mps1 in yeast and humans. Ipl1-dependent phosphorylation of Rad52 facilitates the kinetochore accumulation of Mps1, and Mps1-dependent phosphorylation of Rad52 is important for the accurate regulation of the SAC under spindle damage conditions. Taken together, our data provide detailed insights into the regulatory mechanism of chromosome biorientation by mitotic kinases.
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23
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Tubman ES, Biggins S, Odde DJ. Stochastic Modeling Yields a Mechanistic Framework for Spindle Attachment Error Correction in Budding Yeast Mitosis. Cell Syst 2017; 4:645-650.e5. [PMID: 28601560 DOI: 10.1016/j.cels.2017.05.003] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2016] [Revised: 03/19/2017] [Accepted: 05/05/2017] [Indexed: 12/17/2022]
Abstract
Proper segregation of the replicated genome requires that kinetochores form and maintain bioriented, amphitelic attachments to microtubules from opposite spindle poles and eliminate erroneous, syntelic attachments to microtubules from the same spindle pole. Phosphorylation of kinetochore proteins destabilizes low-tension kinetochore-microtubule attachments, yet tension stabilizes bioriented attachments. This conundrum for forming high-tension amphitelic attachments is recognized as the "initiation problem of biorientation (IPBO)." A delay before kinetochore-microtubule detachment solves the IPBO, but it lacks a mechanistic framework. We developed a stochastic mathematical model for kinetochore-microtubule error correction in yeast that reveals: (1) under low chromatin tension, requiring a large number of phosphorylation events at multiple sites to achieve detachment provides the necessary delay; and (2) kinetochore-induced microtubule depolymerization generates tension in amphitelic, but not syntelic, attachments. With these requirements, the model provides a mechanistic framework for the delay before detachment to solve the IPBO and demonstrates the high degree of amphitely observed experimentally for wild-type spindles under optimal conditions.
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Affiliation(s)
- Emily S Tubman
- Department of Biomedical Engineering, University of Minnesota, Minneapolis, MN 55455, USA
| | - Sue Biggins
- Howard Hughes Medical Institute, Division of Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, WA 98109, USA
| | - David J Odde
- Department of Biomedical Engineering, University of Minnesota, Minneapolis, MN 55455, USA.
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24
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Fong KK, Sarangapani KK, Yusko EC, Riffle M, Llauró A, Graczyk B, Davis TN, Asbury CL. Direct measurement of the strength of microtubule attachment to yeast centrosomes. Mol Biol Cell 2017; 28:1853-1861. [PMID: 28331072 PMCID: PMC5541836 DOI: 10.1091/mbc.e17-01-0034] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2017] [Revised: 03/13/2017] [Accepted: 03/17/2017] [Indexed: 01/14/2023] Open
Abstract
Laser trapping is used to manipulate single attached microtubules in vitro. Direct mechanical measurement shows that attachment of microtubule minus ends to yeast spindle pole bodies is extraordinarily strong. Centrosomes, or spindle pole bodies (SPBs) in yeast, are vital mechanical hubs that maintain load-bearing attachments to microtubules during mitotic spindle assembly, spindle positioning, and chromosome segregation. However, the strength of microtubule-centrosome attachments is unknown, and the possibility that mechanical force might regulate centrosome function has scarcely been explored. To uncover how centrosomes sustain and regulate force, we purified SPBs from budding yeast and used laser trapping to manipulate single attached microtubules in vitro. Our experiments reveal that SPB–microtubule attachments are extraordinarily strong, rupturing at forces approximately fourfold higher than kinetochore attachments under identical loading conditions. Furthermore, removal of the calmodulin-binding site from the SPB component Spc110 weakens SPB–microtubule attachment in vitro and sensitizes cells to increased SPB stress in vivo. These observations show that calmodulin binding contributes to SPB mechanical integrity and suggest that its removal may cause pole delamination and mitotic failure when spindle forces are elevated. We propose that the very high strength of SPB–microtubule attachments may be important for spindle integrity in mitotic cells so that tensile forces generated at kinetochores do not cause microtubule detachment and delamination at SPBs.
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Affiliation(s)
- Kimberly K Fong
- Department of Biochemistry, University of Washington, Seattle, WA 98195
| | - Krishna K Sarangapani
- Department of Physiology and Biophysics, University of Washington, Seattle, WA 98195
| | - Erik C Yusko
- Department of Physiology and Biophysics, University of Washington, Seattle, WA 98195
| | - Michael Riffle
- Department of Biochemistry, University of Washington, Seattle, WA 98195
| | - Aida Llauró
- Department of Physiology and Biophysics, University of Washington, Seattle, WA 98195
| | - Beth Graczyk
- Department of Biochemistry, University of Washington, Seattle, WA 98195
| | - Trisha N Davis
- Department of Biochemistry, University of Washington, Seattle, WA 98195
| | - Charles L Asbury
- Department of Physiology and Biophysics, University of Washington, Seattle, WA 98195
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25
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Coordination of Cell Cycle Progression and Mitotic Spindle Assembly Involves Histone H3 Lysine 4 Methylation by Set1/COMPASS. Genetics 2016; 205:185-199. [PMID: 28049706 DOI: 10.1534/genetics.116.194852] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2016] [Accepted: 11/07/2016] [Indexed: 12/14/2022] Open
Abstract
Methylation of histone H3 lysine 4 (H3K4) by Set1 complex/COMPASS is a hallmark of eukaryotic chromatin, but it remains poorly understood how this post-translational modification contributes to the regulation of biological processes like the cell cycle. Here, we report a H3K4 methylation-dependent pathway in Saccharomyces cerevisiae that governs toxicity toward benomyl, a microtubule destabilizing drug. Benomyl-sensitive growth of wild-type cells required mono- and dimethylation of H3K4 and Pho23, a PHD-containing subunit of the Rpd3L complex. Δset1 and Δpho23 deletions suppressed defects associated with ipl1-2 aurora kinase mutant, an integral component of the spindle assembly checkpoint during mitosis. Benomyl resistance of Δset1 strains was accompanied by deregulation of all four tubulin genes and the phenotype was suppressed by tub2-423 and Δtub3 mutations, establishing a genetic link between H3K4 methylation and microtubule function. Most interestingly, sine wave fitting and clustering of transcript abundance time series in synchronized cells revealed a requirement for Set1 for proper cell-cycle-dependent gene expression and Δset1 cells displayed delayed entry into S phase. Disruption of G1/S regulation in Δmbp1 and Δswi4 transcription factor mutants duplicated both benomyl resistance and suppression of ipl1-2 as was observed with Δset1 Taken together our results support a role for H3K4 methylation in the coordination of cell-cycle progression and proper assembly of the mitotic spindle during mitosis.
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26
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Abstract
SUMMARYAll eukaryotic cells prepare for cell division by forming a "mitotic spindle"-a bipolar machine made from microtubules (MTs) and many associated proteins. This device organizes the already duplicated DNA so one copy of each chromosome attaches to each end of the spindle. Both formation and function of the spindle require controlled MT dynamics, as well as the actions of multiple motor enzymes. Spindle-driven motions separate the duplicated chromosomes into two distinct sets that are then moved toward opposite ends of the cell. The two cells that subsequently form by cytokinesis, therefore, contain all the genes needed to grow and divide again.
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Affiliation(s)
- J Richard McIntosh
- Department of Molecular, Cellular, and Developmental Biology, University of Colorado, Boulder, Colorado 80309-0347
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Tsabar M, Haase J, Harrison B, Snider CE, Eldridge B, Kaminsky L, Hine RM, Haber JE, Bloom K. A Cohesin-Based Partitioning Mechanism Revealed upon Transcriptional Inactivation of Centromere. PLoS Genet 2016; 12:e1006021. [PMID: 27128635 PMCID: PMC4851351 DOI: 10.1371/journal.pgen.1006021] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2015] [Accepted: 04/08/2016] [Indexed: 12/24/2022] Open
Abstract
Transcriptional inactivation of the budding yeast centromere has been a widely used tool in studies of chromosome segregation and aneuploidy. In haploid cells when an essential chromosome contains a single conditionally inactivated centromere (GAL-CEN), cell growth rate is slowed and segregation fidelity is reduced; but colony formation is nearly 100%. Pedigree analysis revealed that only 30% of the time both mother and daughter cell inherit the GAL-CEN chromosome. The reduced segregation capacity of the GAL-CEN chromosome is further compromised upon reduction of pericentric cohesin (mcm21∆), as reflected in a further diminishment of the Mif2 kinetochore protein at GAL-CEN. By redistributing cohesin from the nucleolus to the pericentromere (by deleting SIR2), there is increased presence of the kinetochore protein Mif2 at GAL-CEN and restoration of cell viability. These studies identify the ability of cohesin to promote chromosome segregation via kinetochore assembly, in a situation where the centromere has been severely compromised.
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Affiliation(s)
- Michael Tsabar
- Department of Biology and Rosenstiel Basic Medical Sciences Research Center, Brandeis University, Waltham, Massachusetts, United States of America
| | - Julian Haase
- Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina
| | - Benjamin Harrison
- Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina
| | - Chloe E. Snider
- Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina
| | - Brittany Eldridge
- Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina
| | - Lila Kaminsky
- Department of Biology and Rosenstiel Basic Medical Sciences Research Center, Brandeis University, Waltham, Massachusetts, United States of America
| | - Rebecca M. Hine
- Department of Biology and Rosenstiel Basic Medical Sciences Research Center, Brandeis University, Waltham, Massachusetts, United States of America
| | - James E. Haber
- Department of Biology and Rosenstiel Basic Medical Sciences Research Center, Brandeis University, Waltham, Massachusetts, United States of America
| | - Kerry Bloom
- Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina
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Ladurner R, Kreidl E, Ivanov MP, Ekker H, Idarraga-Amado MH, Busslinger GA, Wutz G, Cisneros DA, Peters JM. Sororin actively maintains sister chromatid cohesion. EMBO J 2016; 35:635-53. [PMID: 26903600 PMCID: PMC4801952 DOI: 10.15252/embj.201592532] [Citation(s) in RCA: 62] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2015] [Accepted: 01/17/2016] [Indexed: 11/26/2022] Open
Abstract
Cohesion between sister chromatids is established during DNA replication but needs to be maintained to enable proper chromosome–spindle attachments in mitosis or meiosis. Cohesion is mediated by cohesin, but also depends on cohesin acetylation and sororin. Sororin contributes to cohesion by stabilizing cohesin on DNA. Sororin achieves this by inhibiting WAPL, which otherwise releases cohesin from DNA and destroys cohesion. Here we describe mouse models which enable the controlled depletion of sororin by gene deletion or auxin‐induced degradation. We show that sororin is essential for embryonic development, cohesion maintenance, and proper chromosome segregation. We further show that the acetyltransferases ESCO1 and ESCO2 are essential for stabilizing cohesin on chromatin, that their only function in this process is to acetylate cohesin's SMC3 subunit, and that DNA replication is also required for stable cohesin–chromatin interactions. Unexpectedly, we find that sororin interacts dynamically with the cohesin complexes it stabilizes. This implies that sororin recruitment to cohesin does not depend on the DNA replication machinery or process itself, but on a property that cohesin acquires during cohesion establishment.
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Affiliation(s)
- Rene Ladurner
- IMP Research Institute of Molecular Pathology, Vienna, Austria
| | - Emanuel Kreidl
- IMP Research Institute of Molecular Pathology, Vienna, Austria
| | | | - Heinz Ekker
- Campus Science Support Facilities NGS Facility, Vienna, Austria
| | | | | | - Gordana Wutz
- IMP Research Institute of Molecular Pathology, Vienna, Austria
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29
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Lawrimore J, Vasquez PA, Falvo MR, Taylor RM, Vicci L, Yeh E, Forest MG, Bloom K. DNA loops generate intracentromere tension in mitosis. J Cell Biol 2015; 210:553-64. [PMID: 26283798 PMCID: PMC4539978 DOI: 10.1083/jcb.201502046] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The geometry and arrangement of DNA loops in the pericentric region of the budding yeast centromere create a DNA-based molecular shock absorber that serves as the basis for how tension is generated between sister centromeres in mitosis. The centromere is the DNA locus that dictates kinetochore formation and is visibly apparent as heterochromatin that bridges sister kinetochores in metaphase. Sister centromeres are compacted and held together by cohesin, condensin, and topoisomerase-mediated entanglements until all sister chromosomes bi-orient along the spindle apparatus. The establishment of tension between sister chromatids is essential for quenching a checkpoint kinase signal generated from kinetochores lacking microtubule attachment or tension. How the centromere chromatin spring is organized and functions as a tensiometer is largely unexplored. We have discovered that centromere chromatin loops generate an extensional/poleward force sufficient to release nucleosomes proximal to the spindle axis. This study describes how the physical consequences of DNA looping directly underlie the biological mechanism for sister centromere separation and the spring-like properties of the centromere in mitosis.
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Affiliation(s)
- Josh Lawrimore
- Department of Biology, University of North Carolina, Chapel Hill, NC 27599
| | - Paula A Vasquez
- Department of Mathematics, University of South Carolina, Columbia, SC 29208
| | - Michael R Falvo
- Department of Physics and Astronomy, University of North Carolina, Chapel Hill, NC 27599
| | - Russell M Taylor
- Department of Computer Science, University of North Carolina, Chapel Hill, NC 27599
| | - Leandra Vicci
- Department of Computer Science, University of North Carolina, Chapel Hill, NC 27599
| | - Elaine Yeh
- Department of Biology, University of North Carolina, Chapel Hill, NC 27599
| | - M Gregory Forest
- Department of Mathematics and Biomedical Engineering, University of North Carolina, Chapel Hill, NC 27599
| | - Kerry Bloom
- Department of Biology, University of North Carolina, Chapel Hill, NC 27599
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30
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Accurate chromosome segregation by probabilistic self-organisation. BMC Biol 2015; 13:65. [PMID: 26264961 PMCID: PMC4533937 DOI: 10.1186/s12915-015-0172-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2015] [Accepted: 06/25/2015] [Indexed: 11/16/2022] Open
Abstract
Background For faithful chromosome segregation during cell division, correct attachments must be established between sister chromosomes and microtubules from opposite spindle poles through kinetochores (chromosome bi-orientation). Incorrect attachments of kinetochore microtubules (kMTs) lead to chromosome mis-segregation and aneuploidy, which is often associated with developmental abnormalities such as Down syndrome and diseases including cancer. The interaction between kinetochores and microtubules is highly dynamic with frequent attachments and detachments. However, it remains unclear how chromosome bi-orientation is achieved with such accuracy in such a dynamic process. Results To gain new insight into this essential process, we have developed a simple mathematical model of kinetochore–microtubule interactions during cell division in general, i.e. both mitosis and meiosis. Firstly, the model reveals that the balance between attachment and detachment probabilities of kMTs is crucial for correct chromosome bi-orientation. With the right balance, incorrect attachments are resolved spontaneously into correct bi-oriented conformations while an imbalance leads to persistent errors. In addition, the model explains why errors are more commonly found in the first meiotic division (meiosis I) than in mitosis and how a faulty conformation can evade the spindle assembly checkpoint, which may lead to a chromosome loss. Conclusions The proposed model, despite its simplicity, helps us understand one of the primary causes of chromosomal instability—aberrant kinetochore–microtubule interactions. The model reveals that chromosome bi-orientation is a probabilistic self-organisation, rather than a sophisticated process of error detection and correction. Electronic supplementary material The online version of this article (doi:10.1186/s12915-015-0172-y) contains supplementary material, which is available to authorized users.
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31
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Abstract
Cells sense biochemical, electrical, and mechanical cues in their environment that affect their differentiation and behavior. Unlike biochemical and electrical signals, mechanical signals can propagate without the diffusion of proteins or ions; instead, forces are transmitted through mechanically stiff structures, flowing, for example, through cytoskeletal elements such as microtubules or filamentous actin. The molecular details underlying how cells respond to force are only beginning to be understood. Here we review tools for probing force-sensitive proteins and highlight several examples in which forces are transmitted, routed, and sensed by proteins in cells. We suggest that local unfolding and tension-dependent removal of autoinhibitory domains are common features in force-sensitive proteins and that force-sensitive proteins may be commonplace wherever forces are transmitted between and within cells. Because mechanical forces are inherent in the cellular environment, force is a signal that cells must take advantage of to maintain homeostasis and carry out their functions.
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Affiliation(s)
- Erik C Yusko
- Department of Physiology and Biophysics, University of Washington, Seattle, WA 98195-7290
| | - Charles L Asbury
- Department of Physiology and Biophysics, University of Washington, Seattle, WA 98195-7290
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Nasmyth K. A meiotic mystery: How sister kinetochores avoid being pulled in opposite directions during the first division. Bioessays 2015; 37:657-65. [PMID: 25874377 PMCID: PMC4683677 DOI: 10.1002/bies.201500006] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2014] [Revised: 03/12/2015] [Accepted: 03/12/2015] [Indexed: 12/21/2022]
Abstract
We now take for granted that despite the disproportionate contribution of females to initial growth of their progeny, there is little or no asymmetry in the contribution of males and females to the eventual character of their shared offspring. In fact, this key insight was only established towards the end of the eighteenth century by Joseph Koelreuter's pioneering plant breeding experiments. If males and females supply equal amounts of hereditary material, then the latter must double each time an embryo is conceived. How then does the amount of this mysterious stuff not multiply exponentially from generation to generation? A compensatory mechanism for diluting the hereditary material must exist, one that ensures that if each parent contributes one half, each grandparent contributes a quarter, and each great grandparent merely an eighth. An important piece of the puzzle of how hereditary material is diluted at each generation has been elucidated over the past ten years.
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Affiliation(s)
- Kim Nasmyth
- Department of Biochemistry, Oxford University, Oxford, UK
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33
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Yang X, Xu W, Hu Z, Zhang Y, Xu N. Chk1 is required for the metaphase-anaphase transition via regulating the expression and localization of Cdc20 and Mad2. Life Sci 2014; 106:12-8. [PMID: 24747134 DOI: 10.1016/j.lfs.2014.04.011] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2014] [Revised: 03/31/2014] [Accepted: 04/07/2014] [Indexed: 11/16/2022]
Abstract
AIMS The checkpoint kinase 1 (Chk1) functions not only in genotoxic stresses but also in normal cell cycle progression, particularly in the initiation, progression and fidelity of unperturbed mitosis. In this study, we investigated the role of Chk1 in regulating the metaphase-anaphase transition in mammalian cells. MAIN METHODS The mitotic progression was monitored by flow cytometry analysis. The levels of cyclin B1, Cdc20 and Mad2 were measured by Western blotting. Metaphase chromosome alignment and the subcellular localization of Cdc20 and Mad2 were analyzed by immunofluorescence and confocal microscopy. KEY FINDINGS Cyclin B1 degradation and the metaphase-anaphase transition were severely blocked by Chk1 siRNA. Depletion of Chk1 induced chromosome alignment defect in metaphase cells. The kinetochore localization of Cdc20, Mad2 was disrupted in Chk1 depleted cells. Chk1 abrogation also dramatically reduced the protein expression levels of Cdc20 and Mad2. SIGNIFICANCE These results strongly suggest that Chk1 is required for the metaphase-anaphase transition via regulating the subcellular localization and the expression of Cdc20 and Mad2.
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Affiliation(s)
- Xiaoyun Yang
- School of Life Sciences, Tsinghua University, Beijing 100084, PR China; Key Lab in Healthy Science and Technology, Division of Life Science, Graduate School at Shenzhen, Tsinghua University, Shenzhen, Guangdong Province, PR China
| | - Wei Xu
- School of Life Sciences, Tsinghua University, Beijing 100084, PR China; Key Lab in Healthy Science and Technology, Division of Life Science, Graduate School at Shenzhen, Tsinghua University, Shenzhen, Guangdong Province, PR China
| | - Zuowei Hu
- Department of Clinical Oncology, Wuhan No. 1 Hospital, Wuhan, Hubei Province, PR China
| | - Yaou Zhang
- Key Lab in Healthy Science and Technology, Division of Life Science, Graduate School at Shenzhen, Tsinghua University, Shenzhen, Guangdong Province, PR China
| | - Naihan Xu
- Key Lab in Healthy Science and Technology, Division of Life Science, Graduate School at Shenzhen, Tsinghua University, Shenzhen, Guangdong Province, PR China.
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34
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Catch and release: how do kinetochores hook the right microtubules during mitosis? Trends Genet 2014; 30:150-9. [PMID: 24631209 DOI: 10.1016/j.tig.2014.02.004] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2013] [Revised: 02/13/2014] [Accepted: 02/14/2014] [Indexed: 11/22/2022]
Abstract
Sport fishermen keep tension on their lines to prevent hooked fish from releasing. A molecular version of this angler's trick, operating at kinetochores, ensures accuracy during mitosis: the mitotic spindle attaches randomly to chromosomes and then correctly bioriented attachments are stabilized due to the tension exerted on them by opposing microtubules. Incorrect attachments, which lack tension, are unstable and release quickly, allowing another chance for biorientation. Stabilization of molecular interactions by tension also occurs in other physiological contexts, such as cell adhesion, motility, hemostasis, and tissue morphogenesis. Here, we review models for the stabilization of kinetochore attachments with an eye toward emerging models for other force-activated systems. Although attention in the mitosis field has focused mainly on one kinase-based mechanism, multiple mechanisms may act together to stabilize properly bioriented kinetochores and some principles governing other tension-sensitive systems may also apply to kinetochores.
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35
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Abstract
The propagation of all organisms depends on the accurate and orderly segregation of chromosomes in mitosis and meiosis. Budding yeast has long served as an outstanding model organism to identify the components and underlying mechanisms that regulate chromosome segregation. This review focuses on the kinetochore, the macromolecular protein complex that assembles on centromeric chromatin and maintains persistent load-bearing attachments to the dynamic tips of spindle microtubules. The kinetochore also serves as a regulatory hub for the spindle checkpoint, ensuring that cell cycle progression is coupled to the achievement of proper microtubule-kinetochore attachments. Progress in understanding the composition and overall architecture of the kinetochore, as well as its properties in making and regulating microtubule attachments and the spindle checkpoint, is discussed.
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36
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Zhang T, Oliveira RA, Schmierer B, Novák B. Dynamical scenarios for chromosome bi-orientation. Biophys J 2014; 104:2595-606. [PMID: 23790367 DOI: 10.1016/j.bpj.2013.05.005] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2013] [Revised: 04/05/2013] [Accepted: 05/01/2013] [Indexed: 02/08/2023] Open
Abstract
Chromosome bi-orientation at the metaphase spindle is essential for precise segregation of the genetic material. The process is error-prone, and error-correction mechanisms exist to switch misaligned chromosomes to the correct, bi-oriented configuration. Here, we analyze several possible dynamical scenarios to explore how cells might achieve correct bi-orientation in an efficient and robust manner. We first illustrate that tension-mediated feedback between the sister kinetochores can give rise to a bistable switch, which allows robust distinction between a loose attachment with low tension and a strong attachment with high tension. However, this mechanism has difficulties in explaining how bi-orientation is initiated starting from unattached kinetochores. We propose four possible mechanisms to overcome this problem (exploiting molecular noise; allowing an efficient attachment of kinetochores already in the absence of tension; a trial-and-error oscillation; and a stochastic bistable switch), and assess their impact on the bi-orientation process. Based on our results and supported by experimental data, we put forward a trial-and-error oscillation and a stochastic bistable switch as two elegant mechanisms with the potential to promote bi-orientation both efficiently and robustly.
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Affiliation(s)
- Tongli Zhang
- Oxford Centre for Integrative Systems Biology, Department of Biochemistry, University of Oxford, Oxford, United Kingdom
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37
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Mailhes JB, Marchetti F. Advances in understanding the genetic causes and mechanisms of female germ cell aneuploidy. ACTA ACUST UNITED AC 2014. [DOI: 10.1586/eog.10.62] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
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38
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Marston AL. Chromosome segregation in budding yeast: sister chromatid cohesion and related mechanisms. Genetics 2014; 196:31-63. [PMID: 24395824 PMCID: PMC3872193 DOI: 10.1534/genetics.112.145144] [Citation(s) in RCA: 69] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2013] [Accepted: 09/18/2013] [Indexed: 12/28/2022] Open
Abstract
Studies on budding yeast have exposed the highly conserved mechanisms by which duplicated chromosomes are evenly distributed to daughter cells at the metaphase-anaphase transition. The establishment of proteinaceous bridges between sister chromatids, a function provided by a ring-shaped complex known as cohesin, is central to accurate segregation. It is the destruction of this cohesin that triggers the segregation of chromosomes following their proper attachment to microtubules. Since it is irreversible, this process must be tightly controlled and driven to completion. Furthermore, during meiosis, modifications must be put in place to allow the segregation of maternal and paternal chromosomes in the first division for gamete formation. Here, I review the pioneering work from budding yeast that has led to a molecular understanding of the establishment and destruction of cohesion.
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Affiliation(s)
- Adele L Marston
- The Wellcome Trust Centre for Cell Biology, School of Biological Sciences, University of Edinburgh, Edinburgh EH9 3JR, United Kingdom
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39
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Tanaka TU, Clayton L, Natsume T. Three wise centromere functions: see no error, hear no break, speak no delay. EMBO Rep 2013; 14:1073-83. [PMID: 24232185 PMCID: PMC3849490 DOI: 10.1038/embor.2013.181] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2013] [Accepted: 10/18/2013] [Indexed: 12/17/2022] Open
Abstract
The main function of the centromere is to promote kinetochore assembly for spindle microtubule attachment. Two additional functions of the centromere, however, are becoming increasingly clear: facilitation of robust sister-chromatid cohesion at pericentromeres and advancement of replication of centromeric regions. The combination of these three centromere functions ensures correct chromosome segregation during mitosis. Here, we review the mechanisms of the kinetochore-microtubule interaction, focusing on sister-kinetochore bi-orientation (or chromosome bi-orientation). We also discuss the biological importance of robust pericentromeric cohesion and early centromere replication, as well as the mechanisms orchestrating these two functions at the microtubule attachment site.
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Affiliation(s)
- Tomoyuki U Tanaka
- Centre for Gene Regulation and Expression, College of Life Sciences, University of Dundee, Dow Street, Dundee DD1 5EH, UK
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40
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Akhshi TK, Wernike D, Piekny A. Microtubules and actin crosstalk in cell migration and division. Cytoskeleton (Hoboken) 2013; 71:1-23. [DOI: 10.1002/cm.21150] [Citation(s) in RCA: 110] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2013] [Revised: 10/02/2013] [Accepted: 10/06/2013] [Indexed: 12/22/2022]
Affiliation(s)
| | - Denise Wernike
- Department of Biology; Concordia University; Montreal Quebec Canada
| | - Alisa Piekny
- Department of Biology; Concordia University; Montreal Quebec Canada
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41
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Phosphoregulation promotes release of kinetochores from dynamic microtubules via multiple mechanisms. Proc Natl Acad Sci U S A 2013; 110:7282-7. [PMID: 23589891 DOI: 10.1073/pnas.1220700110] [Citation(s) in RCA: 63] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
During mitosis, multiprotein complexes called kinetochores orchestrate chromosome segregation by forming load-bearing attachments to dynamic microtubule tips, and by participating in phosphoregulatory error correction. The conserved kinase Aurora B phosphorylates the major microtubule-binding kinetochore subcomplexes, Ndc80 and (in yeast) Dam1, to promote release of erroneous attachments, giving another chance for proper attachments to form. It is unknown whether Aurora B phosphorylation promotes release directly, by increasing the rate of kinetochore detachment, or indirectly, by destabilizing the microtubule tip. Moreover, the relative importance of phosphorylation of Ndc80 vs. Dam1 in the context of whole kinetochores is unclear. To address these uncertainties, we isolated native yeast kinetochore particles carrying phosphomimetic mutations on Ndc80 and Dam1, and applied advanced laser-trapping techniques to measure the strength and stability of their attachments to individual dynamic microtubule tips. Rupture forces were reduced by phosphomimetic mutations on both subcomplexes, in an additive manner, indicating that both subcomplexes make independent contributions to attachment strength. Phosphomimetics on either subcomplex reduced attachment lifetimes under constant force, primarily by accelerating detachment during microtubule growth. Phosphomimetics on Dam1 also increased the likelihood of switches from microtubule growth into shortening, further promoting release in an indirect manner. Taken together, our results suggest that, in vivo, Aurora B releases kinetochores via at least two mechanisms: by weakening the kinetochore-microtubule interface and also by destabilizing the kinetochore-attached microtubule tip.
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43
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Carvalho TG, Doerig C, Reininger L. Nima- and Aurora-related kinases of malaria parasites. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2013; 1834:1336-45. [PMID: 23462523 DOI: 10.1016/j.bbapap.2013.02.022] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/08/2012] [Accepted: 02/14/2013] [Indexed: 10/27/2022]
Abstract
Completion of the life cycle of malaria parasite requires a succession of developmental stages which vary greatly with respect to proliferation status, implying a tightly regulated control of the parasite's cell cycle, which remains to be understood at the molecular level. Progression of the eukaryotic cell cycle is controlled by members of mitotic kinase of the families CDK (cyclin-dependent kinases), Aurora, Polo and NIMA. Plasmodium parasites possess cyclin-dependent protein kinases and cyclins, which strongly suggests that some of the principles underlying cell cycle control in higher eukaryotes also operate in this organism. However, atypical features of Plasmodium cell cycle organization and important divergences in the composition of the cell cycle machinery suggest the existence of regulatory mechanisms that are at variance with those of higher eukaryotes. This review focuses on several recently described Plasmodium protein kinases related to the NIMA and Aurora kinase families and discusses their functional involvement in parasite's biology. Given their demonstrated essential roles in the erythrocytic asexual cycle and/or sexual stages, these enzymes represent novel potential drug targets for antimalarial intervention aiming at inhibiting parasite replication and/or blocking transmission of the disease. This article is part of a Special Issue entitled: Inhibitors of Protein Kinases (2012).
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Affiliation(s)
- Teresa Gil Carvalho
- Department of Microbiology, Monash University, Wellington Road, Clayton, VIC 3800, Australia
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44
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Wu Q, Zhang W, Mu T, Song T, Li D. Aurora B kinase is required for cytokinesis through effecting spindle structure. Cell Biol Int 2013; 37:436-42. [PMID: 23584797 DOI: 10.1002/cbin.10057] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2012] [Accepted: 01/10/2013] [Indexed: 11/08/2022]
Abstract
The spindle, composed of microtubules and associated proteins, serves as major machinery for cell division. Aurora B is a chromosome passenger protein that has important functions in mitosis. Its dynamic distribution at mitosis goes along with spindle structure and dynamics. We used the siRNA technique to knockdown protein expression and immunofluorescence technique to follow Aurora B during mitosis. Aurora B regulates microtubule plus ends as mitosis progresses, including both kinetochore and polar microtubules. Interactions between Aurora B and polar microtubule plus ends lead to failure in cytokinesis and abnormal midbody structure. We think Aurora B may not only play a role as kinase, but regulate microtubule plus ends.
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Affiliation(s)
- Qiang Wu
- Department of Hepatobiliary Surgery, Tianjin Medical University Cancer Institute and Hospital, Key Laboratory of Cancer Prevention and Therapy, China
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45
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Tanaka K. Regulatory mechanisms of kinetochore-microtubule interaction in mitosis. Cell Mol Life Sci 2013; 70:559-79. [PMID: 22752158 PMCID: PMC11113415 DOI: 10.1007/s00018-012-1057-7] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2012] [Revised: 05/29/2012] [Accepted: 06/11/2012] [Indexed: 12/17/2022]
Abstract
Interaction of microtubules with kinetochores is fundamental to chromosome segregation. Kinetochores initially associate with lateral surfaces of microtubules and subsequently become attached to microtubule ends. During these interactions, kinetochores can move by sliding along microtubules or by moving together with depolymerizing microtubule ends. The interplay between kinetochores and microtubules leads to the establishment of bi-orientation, which is the attachment of sister kinetochores to microtubules from opposite spindle poles, and subsequent chromosome segregation. Molecular mechanisms underlying these processes have been intensively studied over the past 10 years. Emerging evidence suggests that the KNL1-Mis12-Ndc80 (KMN) network plays a central role in connecting kinetochores to microtubules, which is under fine regulation by a mitotic kinase, Aurora B. However, a growing number of additional molecules are being shown to be involved in the kinetochore-microtubule interaction. Here I overview the current range of regulatory mechanisms of the kinetochore-microtubule interaction, and discuss how these multiple molecules contribute cooperatively to allow faithful chromosome segregation.
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Affiliation(s)
- Kozo Tanaka
- Department of Molecular Oncology, Institute of Development, Aging and Cancer, Tohoku University, 4-1 Seiryo-machi, Aoba-ku, Sendai, 980-8575, Miyagi, Japan.
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46
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Vagnarelli P. Chromatin reorganization through mitosis. ADVANCES IN PROTEIN CHEMISTRY AND STRUCTURAL BIOLOGY 2013; 90:179-224. [PMID: 23582205 DOI: 10.1016/b978-0-12-410523-2.00006-7] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Chromosome condensation is one of the major chromatin-remodeling events that occur during cell division. The changes in chromatin compaction and higher-order structure organization are essential requisites for ensuring a faithful transmission of the replicated genome to daughter cells. Although the observation of mitotic chromosome condensation has fascinated Scientists for a century, we are still far away from understanding how the process works from a molecular point of view. In this chapter, I will analyze our current understanding of chromatin condensation during mitosis with particular attention to the major molecular players that trigger and maintain this particular chromatin conformation. However, within the chromosome, not all regions of the chromatin are organized in the same manner. I will address separately the structure and functions of particular chromatin domains such as the centromere. Finally, the transition of the chromatin through mitosis represents just an interlude for gene expression between two cell cycles. How the transcriptional information that governs cell linage identity is transmitted from mother to daughter represents a big and interesting question. I will present how cells take care of the aspect ensuring that mitotic chromosome condensation and the block of transcription does not wipe out the cell identity.
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Affiliation(s)
- Paola Vagnarelli
- Heinz Wolff Building, Brunel University, Uxbridge, United Kingdom.
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Moutinho-Santos T, Conde C, Sunkel CE. POLO ensures chromosome bi-orientation by preventing and correcting erroneous chromosome-spindle attachments. J Cell Sci 2012; 125:576-83. [PMID: 22389397 DOI: 10.1242/jcs.092445] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Correct chromosome segregation during cell division requires bi-orientation at the mitotic spindle. Cells possess mechanisms to prevent and correct inappropriate chromosome attachment. Sister kinetochores assume a 'back-to-back' geometry on chromosomes that favors amphitelic orientation but the regulation of this process and molecular components are unknown. Abnormal chromosome-spindle interactions do occur but are corrected through the activity of Aurora B, which destabilizes erroneous attachments. Here, we address the role of Drosophila POLO in chromosome-spindle interactions and show that, unlike inhibition of its activity, depletion of the protein results in bipolar spindles with most chromosomes forming stable attachments with both sister kinetochores bound to microtubules from the same pole in a syntelic orientation. This is partly the result of impaired localization and activity of Aurora B but also of an altered centromere organization with abnormal distribution of centromeric proteins and shorter interkinetochore distances. Our results suggests that POLO is required to promote amphitelic attachment and chromosome bi-orientation by regulating both the activity of the correction mechanism and the architecture of the centromere.
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Akiyoshi B, Biggins S. Reconstituting the kinetochore–microtubule interface: what, why, and how. Chromosoma 2012; 121:235-50. [PMID: 22289864 DOI: 10.1007/s00412-012-0362-0] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2011] [Revised: 01/15/2012] [Accepted: 01/16/2012] [Indexed: 10/14/2022]
Abstract
The kinetochore is the proteinaceous complex that governs the movement of duplicated chromosomes by interacting with spindle microtubules during mitosis and meiosis. Faithful chromosome segregation requires that kinetochores form robust load-bearing attachments to the tips of dynamic spindle microtubules, correct microtubule attachment errors, and delay the onset of anaphase until all chromosomes have made proper attachments. To understand how this macromolecular machine operates to segregate duplicated chromosomes with exquisite accuracy, it is critical to reconstitute and study kinetochore–microtubule interactions in vitro using defined components. Here, we review the current status of reconstitution as well as recent progress in understanding the microtubule-binding functions of kinetochores in vivo.
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Affiliation(s)
- Bungo Akiyoshi
- Sir William Dunn School of Pathology, University of Oxford, Oxford OX1 3RE, UK.
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Khong JH, Zhang T, Gunaratne J, Blackstock W, Surana U. "Reductional anaphase" in replication-defective cells is caused by ubiquitin-conjugating enzyme Cdc34-mediated deregulation of the spindle. Cell Cycle 2012; 11:2896-910. [PMID: 22805765 DOI: 10.4161/cc.21303] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Equal partitioning of the duplicated chromosomes into two daughter cells during cell division is a coordinated process and is initiated only after completion of DNA synthesis. However, this strict order of execution breaks down in CDC6-deficient cells. Cdc6, an evolutionarily conserved protein, is required for the assembly of pre-replicative complexes (pre-RCs) and is essential for the initiation of DNA replication. Yeast cells lacking Cdc6 function, though unable to initiate DNA replication, proceed to undergo "reductional anaphase" by partitioning the unreplicated chromosomes and lose viability rapidly. This extreme form of genomic instability in cdc6 cells is thought to be due to inactivation of a pre-RC based, Cdc6-dependent checkpoint mechanism that, during normal cell cycle, inhibits premature onset of mitosis until pre-RC is assembled. Here, we show that chromosome segregation in cdc6 mutant is caused not by precocious initiation of mitosis in the absence of a checkpoint, but by the deregulation of spindle dynamics induced via a regulatory network involving the ubiquitin-conjugating enzyme Cdc34, microtubule-associated proteins (MAPs) and the anaphase-promoting complex (APC) activator Cdh1. This regulatory circuit governs spindle behavior in the early part of the division cycle and precipitates catastrophic chromosome segregation in the absence of DNA replication.
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Affiliation(s)
- Jenn Hui Khong
- Institute of Molecular and Cell Biology, A*STAR (Agency for Science, Technology and Research), Singapore
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50
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Umbreit NT, Davis TN. Mitosis puts sisters in a strained relationship: force generation at the kinetochore. Exp Cell Res 2012; 318:1361-6. [PMID: 22564894 DOI: 10.1016/j.yexcr.2012.04.008] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2012] [Revised: 04/21/2012] [Accepted: 04/23/2012] [Indexed: 11/24/2022]
Abstract
During mitosis, kinetochores couple chromosomes to the dynamic tips of spindle microtubules. These attachments convert chemical energy stored in the microtubule lattice into mechanical energy, generating force to move chromosomes. In addition to mediating robust microtubule attachments, kinetochores also integrate and respond to regulatory signals that ensure the accuracy of chromosome segregation during each cell division. Signals for corrective detachment act specifically on kinetochore-microtubule attachments that fail to generate normal levels of tension, although it is unclear how tension is sensed and how the attachments are released. In this review, we discuss the mechanisms by which kinetochore-microtubule attachments generate force during chromosome biorientation, and the pathways of maturation and regulation that lead to the formation of correct attachments.
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Affiliation(s)
- Neil T Umbreit
- Department of Biochemistry, University of Washington, Seattle, WA 98195, USA
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