1
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Anjur-Dietrich MI, Gomez Hererra V, Farhadifar R, Wu H, Merta H, Bahmanyar S, Shelley MJ, Needleman DJ. Mechanics of spindle orientation in human mitotic cells is determined by pulling forces on astral microtubules and clustering of cortical dynein. Dev Cell 2024:S1534-5807(24)00340-X. [PMID: 38866013 DOI: 10.1016/j.devcel.2024.05.022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2023] [Revised: 04/03/2024] [Accepted: 05/17/2024] [Indexed: 06/14/2024]
Abstract
The forces that orient the spindle in human cells remain poorly understood due to a lack of direct mechanical measurements in mammalian systems. We use magnetic tweezers to measure the force on human mitotic spindles. Combining the spindle's measured resistance to rotation, the speed at which it rotates after laser ablating astral microtubules, and estimates of the number of ablated microtubules reveals that each microtubule contacting the cell cortex is subject to ∼5 pN of pulling force, suggesting that each is pulled on by an individual dynein motor. We find that the concentration of dynein at the cell cortex and extent of dynein clustering are key determinants of the spindle's resistance to rotation, with little contribution from cytoplasmic viscosity, which we explain using a biophysically based mathematical model. This work reveals how pulling forces on astral microtubules determine the mechanics of spindle orientation and demonstrates the central role of cortical dynein clustering.
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Affiliation(s)
- Maya I Anjur-Dietrich
- School of Engineering and Applied Sciences, Harvard University, Cambridge, MA 02138, USA.
| | - Vicente Gomez Hererra
- Courant Institute of Mathematical Sciences, New York University, New York, NY 10012, USA
| | - Reza Farhadifar
- Center for Computational Biology, Flatiron Institute, New York, NY 10010, USA
| | - Haiyin Wu
- Department of Physics, Harvard University, Cambridge, MA 02138, USA; Department of Molecular and Cellular Biology, Harvard University, Cambridge, MA 02138, USA
| | - Holly Merta
- Department of Molecular, Cellular, and Developmental Biology, Yale University, New Haven, CT 06520, USA
| | - Shirin Bahmanyar
- Department of Molecular, Cellular, and Developmental Biology, Yale University, New Haven, CT 06520, USA
| | - Michael J Shelley
- Courant Institute of Mathematical Sciences, New York University, New York, NY 10012, USA; Center for Computational Biology, Flatiron Institute, New York, NY 10010, USA
| | - Daniel J Needleman
- School of Engineering and Applied Sciences, Harvard University, Cambridge, MA 02138, USA; Department of Molecular and Cellular Biology, Harvard University, Cambridge, MA 02138, USA; Center for Computational Biology, Flatiron Institute, New York, NY 10010, USA
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2
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Sen A, Chowdhury D, Kunwar A. Coordination, cooperation, competition, crowding and congestion of molecular motors: Theoretical models and computer simulations. ADVANCES IN PROTEIN CHEMISTRY AND STRUCTURAL BIOLOGY 2024; 141:563-650. [PMID: 38960486 DOI: 10.1016/bs.apcsb.2023.12.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/05/2024]
Abstract
Cytoskeletal motor proteins are biological nanomachines that convert chemical energy into mechanical work to carry out various functions such as cell division, cell motility, cargo transport, muscle contraction, beating of cilia and flagella, and ciliogenesis. Most of these processes are driven by the collective operation of several motors in the crowded viscous intracellular environment. Imaging and manipulation of the motors with powerful experimental probes have been complemented by mathematical analysis and computer simulations of the corresponding theoretical models. In this article, we illustrate some of the key theoretical approaches used to understand how coordination, cooperation and competition of multiple motors in the crowded intra-cellular environment drive the processes that are essential for biological function of a cell. In spite of the focus on theory, experimentalists will also find this article as an useful summary of the progress made so far in understanding multiple motor systems.
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Affiliation(s)
- Aritra Sen
- Department of Biosciences and Bioengineering, Indian Institute of Technology Bombay, Mumbai, Maharashtra, India
| | - Debashish Chowdhury
- Department of Physics, Indian Institute of Technology Kanpur, Kanpur, Uttar Pradesh, India
| | - Ambarish Kunwar
- Department of Biosciences and Bioengineering, Indian Institute of Technology Bombay, Mumbai, Maharashtra, India.
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3
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Yamamoto T, Uehara R. Cell shape instability during cytokinesis in tetraploid HCT116 cells. Biochem Biophys Res Commun 2023; 678:39-44. [PMID: 37619310 DOI: 10.1016/j.bbrc.2023.08.038] [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: 08/05/2023] [Accepted: 08/16/2023] [Indexed: 08/26/2023]
Abstract
Tetraploidy is a hallmark of broad cancer types, but it remains largely unknown which aspects of cellular processes are influenced by tetraploidization in human cells. Here, we found that tetraploid HCT116 cells manifested severe cell shape instability during cytokinesis, unlike their diploid counterparts. The cell shape instability accompanied the formation of protrusive deformation at the cell poles, indicating ectopic contractile activity of the cell cortex. While cytokinesis regulators such as RhoA and anillin correctly accumulated at the equatorial cortex, myosin II was over-accumulated at the cell poles, specifically in tetraploid cells. Suppression of myosin II activity by Y27632 treatment restored smooth cell shape in tetraploids during cytokinesis, indicating dysregulation of myosin II as a primary cause of the cell shape instability in the tetraploid state. Our results demonstrate a new aspect of the dynamic cellular process profoundly affected by tetraploidization in human cells, which provides a clue to molecular mechanisms of tetraploidy-driven pathogenic processes.
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Affiliation(s)
| | - Ryota Uehara
- Graduate School of Life Science, Hokkaido University, Japan; Faculty of Advanced Life Science, Hokkaido University, Japan.
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4
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Anjur-Dietrich MI, Hererra VG, Farhadifar R, Wu H, Merta H, Bahmanyar S, Shelley MJ, Needleman DJ. Clustering of cortical dynein regulates the mechanics of spindle orientation in human mitotic cells. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.09.11.557210. [PMID: 37745442 PMCID: PMC10515834 DOI: 10.1101/2023.09.11.557210] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/26/2023]
Abstract
The forces which orient the spindle in human cells remain poorly understood due to a lack of direct mechanical measurements in mammalian systems. We use magnetic tweezers to measure the force on human mitotic spindles. Combining the spindle's measured resistance to rotation, the speed it rotates after laser ablating astral microtubules, and estimates of the number of ablated microtubules reveals that each microtubule contacting the cell cortex is subject to ~1 pN of pulling force, suggesting that each is pulled on by an individual dynein motor. We find that the concentration of dynein at the cell cortex and extent of dynein clustering are key determinants of the spindle's resistance to rotation, with little contribution from cytoplasmic viscosity, which we explain using a biophysically based mathematical model. This work reveals how pulling forces on astral microtubules determine the mechanics of spindle orientation and demonstrates the central role of cortical dynein clustering.
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Affiliation(s)
- Maya I. Anjur-Dietrich
- School of Engineering and Applied Sciences, Harvard University, Cambridge, MA 02138, USA
| | - Vicente Gomez Hererra
- Courant Institute of Mathematical Sciences, New York University, New York, NY 10012, USA
| | - Reza Farhadifar
- Center for Computational Biology, Flatiron Institute, New York, NY 10010, USA
| | - Haiyin Wu
- Department of Physics, Harvard University, Cambridge, MA 02138, USA
- Department of Molecular and Cellular Biology, Harvard University, Cambridge, MA 02138, USA
| | - Holly Merta
- Department of Molecular, Cellular, and Developmental Biology, Yale University, New Haven, CT 06520, USA
| | - Shirin Bahmanyar
- Department of Molecular, Cellular, and Developmental Biology, Yale University, New Haven, CT 06520, USA
| | - Michael J. Shelley
- Courant Institute of Mathematical Sciences, New York University, New York, NY 10012, USA
- Center for Computational Biology, Flatiron Institute, New York, NY 10010, USA
| | - Daniel J. Needleman
- School of Engineering and Applied Sciences, Harvard University, Cambridge, MA 02138, USA
- Department of Molecular and Cellular Biology, Harvard University, Cambridge, MA 02138, USA
- Center for Computational Biology, Flatiron Institute, New York, NY 10010, USA
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5
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McHugh T, Welburn JPI. Potent microtubule-depolymerizing activity of a mitotic Kif18b-MCAK-EB network. J Cell Sci 2023; 136:275263. [PMID: 35502670 DOI: 10.1242/jcs.260144] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2022] [Accepted: 04/21/2022] [Indexed: 11/20/2022] Open
Abstract
The precise regulation of microtubule length during mitosis is essential to assemble and position the mitotic spindle and segregate chromosomes. The kinesin-13 Kif2C or MCAK acts as a potent microtubule depolymerase that diffuses short distances on microtubules, whereas the kinesin-8 Kif18b is a processive motor with weak depolymerase activity. However, the individual activities of these factors cannot explain the dramatic increase in microtubule dynamics in mitosis. Using in vitro reconstitution and single-molecule imaging, we demonstrate that Kif18b, MCAK and the plus-end tracking protein EB3 (also known as MAPRE3) act in an integrated manner to potently promote microtubule depolymerization at very low concentrations. We find that Kif18b can transport EB3 and MCAK and promotes their accumulation to microtubule plus ends through multivalent weak interactions. Together, our work defines the mechanistic basis for a cooperative Kif18b-MCAK-EB network at microtubule plus ends, that acts to efficiently shorten and regulate microtubules in mitosis, essential for correct chromosome segregation.
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Affiliation(s)
- Toni McHugh
- Wellcome Trust Centre for Cell Biology, School of Biological Sciences, University of Edinburgh, Edinburgh EH9 3BF, Scotland, UK
| | - Julie P I Welburn
- Wellcome Trust Centre for Cell Biology, School of Biological Sciences, University of Edinburgh, Edinburgh EH9 3BF, Scotland, UK
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6
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Shindo N, Kumada K, Iemura K, Yasuda J, Fujimori H, Mochizuki M, Tamai K, Tanaka K, Hirota T. Autocleavage of separase suppresses its premature activation by promoting binding to cyclin B1. Cell Rep 2022; 41:111723. [PMID: 36450246 DOI: 10.1016/j.celrep.2022.111723] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2022] [Revised: 09/25/2022] [Accepted: 11/03/2022] [Indexed: 12/02/2022] Open
Abstract
Accurate chromosome segregation requires timely activation of separase, a protease that cleaves cohesin during the metaphase-to-anaphase transition. However, the mechanism that maintains the inactivity of separase prior to this event remains unclear. We provide evidence that separase autocleavage plays an essential role in this process. We show that the inhibition of separase autocleavage results in premature activity before the onset of anaphase, accompanied by the formation of chromosomal bridges and spindle rocking. This deregulation is attributed to the reduced binding of cyclin B1 to separase that occurs during the metaphase-to-anaphase transition. Furthermore, when separase is mutated to render the regulation by cyclin B1 irrelevant, which keeps separase in securin-binding form, the deregulation induced by autocleavage inhibition is rescued. Our results reveal a physiological role of separase autocleavage in regulating separase, which ensures faithful chromosome segregation.
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Affiliation(s)
- Norihisa Shindo
- Division of Molecular and Cellular Oncology, Miyagi Cancer Center Research Institute, Natori, Japan.
| | - Kazuki Kumada
- Tohoku Medical Megabank Organization, Tohoku University, Sendai, Japan
| | - Kenji Iemura
- Department of Molecular Oncology, Institute of Development, Aging and Cancer, Tohoku University, Sendai, Japan
| | - Jun Yasuda
- Division of Molecular and Cellular Oncology, Miyagi Cancer Center Research Institute, Natori, Japan
| | - Haruna Fujimori
- Division of Cancer Stem Cell, Miyagi Cancer Center Research Institute, Natori, Japan
| | - Mai Mochizuki
- Division of Cancer Stem Cell, Miyagi Cancer Center Research Institute, Natori, Japan
| | - Keiichi Tamai
- Division of Cancer Stem Cell, Miyagi Cancer Center Research Institute, Natori, Japan
| | - Kozo Tanaka
- Department of Molecular Oncology, Institute of Development, Aging and Cancer, Tohoku University, Sendai, Japan
| | - Toru Hirota
- Division of Experimental Pathology, Cancer Institute of the Japanese Foundation for Cancer Research (JFCR), Tokyo, Japan
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7
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Inhibition of polar actin assembly by astral microtubules is required for cytokinesis. Nat Commun 2021; 12:2409. [PMID: 33893302 PMCID: PMC8065111 DOI: 10.1038/s41467-021-22677-0] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2020] [Accepted: 03/19/2021] [Indexed: 02/07/2023] Open
Abstract
During cytokinesis, the actin cytoskeleton is partitioned into two spatially distinct actin isoform specific networks: a β-actin network that generates the equatorial contractile ring, and a γ-actin network that localizes to the cell cortex. Here we demonstrate that the opposing regulation of the β- and γ-actin networks is required for successful cytokinesis. While activation of the formin DIAPH3 at the cytokinetic furrow underlies β-actin filament production, we show that the γ-actin network is specifically depleted at the cell poles through the localized deactivation of the formin DIAPH1. During anaphase, CLIP170 is delivered by astral microtubules and displaces IQGAP1 from DIAPH1, leading to formin autoinhibition, a decrease in cortical stiffness and localized membrane blebbing. The contemporaneous production of a β-actin contractile ring at the cell equator and loss of γ-actin from the poles is required to generate a stable cytokinetic furrow and for the completion of cell division. During cell division, the actin cytoskeletal network at both the equatorial contractile ring and cell cortex are known to play a role, but the regulation of γ-actin during cytokinesis is less well understood. Here, the authors show that recruitment of β-actin to the contractile ring and loss of γ-actin from the cell poles is required for completion of cell division.
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8
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Bozal-Basterra L, Gonzalez-Santamarta M, Muratore V, Martín-Martín N, Ercilla A, Rodríguez JA, Carracedo A, Sutherland JD, Barrio R. LUZP1 Controls Cell Division, Migration and Invasion Through Regulation of the Actin Cytoskeleton. Front Cell Dev Biol 2021; 9:624089. [PMID: 33869174 PMCID: PMC8049182 DOI: 10.3389/fcell.2021.624089] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2020] [Accepted: 03/03/2021] [Indexed: 12/21/2022] Open
Abstract
LUZP1 is a centrosomal and actin cytoskeleton-localizing protein that regulates both ciliogenesis and actin filament bundling. As the cytoskeleton and cilia are implicated in metastasis and tumor suppression, we examined roles for LUZP1 in the context of cancer. Here we show that LUZP1 exhibits frequent genomic aberrations in cancer, with a predominance of gene deletions. Furthermore, we demonstrate that CRISPR/Cas9-mediated loss of Luzp1 in mouse fibroblasts promotes cell migration and invasion features, reduces cell viability, and increases cell apoptosis, centriole numbers, and nuclear size while altering the actin cytoskeleton. Loss of Luzp1 also induced changes to ACTR3 (Actin Related Protein 3, also known as ARP3) and phospho-cofilin ratios, suggesting regulatory roles in actin polymerization, beyond its role in filament bundling. Our results point to an unprecedented role for LUZP1 in the regulation of cancer features through the control of actin cytoskeleton.
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Affiliation(s)
- Laura Bozal-Basterra
- Center for Cooperative Research in Biosciences (CIC BioGUNE), Basque Research and Technology Alliance, Bizkaia Technology Park, Derio, Spain
| | - María Gonzalez-Santamarta
- Center for Cooperative Research in Biosciences (CIC BioGUNE), Basque Research and Technology Alliance, Bizkaia Technology Park, Derio, Spain
| | - Veronica Muratore
- Center for Cooperative Research in Biosciences (CIC BioGUNE), Basque Research and Technology Alliance, Bizkaia Technology Park, Derio, Spain
| | - Natalia Martín-Martín
- Center for Cooperative Research in Biosciences (CIC BioGUNE), Basque Research and Technology Alliance, Bizkaia Technology Park, Derio, Spain
| | - Amaia Ercilla
- Center for Cooperative Research in Biosciences (CIC BioGUNE), Basque Research and Technology Alliance, Bizkaia Technology Park, Derio, Spain.,Centro de Investigación Biomédica en Red de Cáncer (CIBERONC), Instituto de Salud Carlos III, Madrid, Spain
| | - Jose A Rodríguez
- Department of Genetics, Physical Anthropology and Animal Physiology, University of the Basque Country Universidad del País Vasco/Euskal Herriko Unibertsitatea (UPV/EHU), Leioa, Spain
| | - Arkaitz Carracedo
- Center for Cooperative Research in Biosciences (CIC BioGUNE), Basque Research and Technology Alliance, Bizkaia Technology Park, Derio, Spain.,Centro de Investigación Biomédica en Red de Cáncer (CIBERONC), Instituto de Salud Carlos III, Madrid, Spain.,Ikerbasque, Basque Foundation for Science, Bilbao, Spain.,Biochemistry and Molecular Biology Department, University of the Basque Country (UPV/EHU), Leioa, Spain
| | - James D Sutherland
- Center for Cooperative Research in Biosciences (CIC BioGUNE), Basque Research and Technology Alliance, Bizkaia Technology Park, Derio, Spain
| | - Rosa Barrio
- Center for Cooperative Research in Biosciences (CIC BioGUNE), Basque Research and Technology Alliance, Bizkaia Technology Park, Derio, Spain
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9
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Chapa-Y-Lazo B, Hamanaka M, Wray A, Balasubramanian MK, Mishima M. Polar relaxation by dynein-mediated removal of cortical myosin II. J Cell Biol 2021; 219:151836. [PMID: 32497213 PMCID: PMC7401816 DOI: 10.1083/jcb.201903080] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2019] [Revised: 02/03/2020] [Accepted: 05/04/2020] [Indexed: 12/24/2022] Open
Abstract
Nearly six decades ago, Lewis Wolpert proposed the relaxation of the polar cell cortex by the radial arrays of astral microtubules as a mechanism for cleavage furrow induction. While this mechanism has remained controversial, recent work has provided evidence for polar relaxation by astral microtubules, although its molecular mechanisms remain elusive. Here, using C. elegans embryos, we show that polar relaxation is achieved through dynein-mediated removal of myosin II from the polar cortexes. Mutants that position centrosomes closer to the polar cortex accelerated furrow induction, whereas suppression of dynein activity delayed furrowing. We show that dynein-mediated removal of myosin II from the polar cortexes triggers a bidirectional cortical flow toward the cell equator, which induces the assembly of the actomyosin contractile ring. These results provide a molecular mechanism for the aster-dependent polar relaxation, which works in parallel with equatorial stimulation to promote robust cytokinesis.
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Affiliation(s)
- Bernardo Chapa-Y-Lazo
- Centre for Mechanochemical Cell Biology & Division of Biomedical Sciences, Warwick Medical School, Coventry, UK
| | - Motonari Hamanaka
- Centre for Mechanochemical Cell Biology & Division of Biomedical Sciences, Warwick Medical School, Coventry, UK.,Hokkaido University, Sapporo, Japan
| | - Alexander Wray
- Centre for Mechanochemical Cell Biology & Division of Biomedical Sciences, Warwick Medical School, Coventry, UK.,University of Nottingham, Nottingham, UK
| | - Mohan K Balasubramanian
- Centre for Mechanochemical Cell Biology & Division of Biomedical Sciences, Warwick Medical School, Coventry, UK
| | - Masanori Mishima
- Centre for Mechanochemical Cell Biology & Division of Biomedical Sciences, Warwick Medical School, Coventry, UK
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10
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Schneid S, Wolff F, Buchner K, Bertram N, Baygün S, Barbosa P, Mangal S, Zanin E. The BRCT domains of ECT2 have distinct functions during cytokinesis. Cell Rep 2021; 34:108805. [PMID: 33657383 DOI: 10.1016/j.celrep.2021.108805] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2020] [Revised: 12/18/2020] [Accepted: 02/08/2021] [Indexed: 12/28/2022] Open
Abstract
During cell division, the guanine nucleotide exchange factor (GEF) ECT2 activates RhoA in a narrow zone at the cell equator in anaphase. ECT2 consists of three BRCT domains (BRCT0, 1, and 2), a catalytic GEF, and a pleckstrin homology (PH) domain. How the conserved BRCT domains spatially and temporally control ECT2 activity remains unclear. We reveal that each BRCT domain makes distinct contributions to the ECT2 function. We find that BRCT0 contributes to, and BRCT1 is essential for, ECT2 activation in anaphase. BRCT2 integrates two functions: GEF inhibition and RACGAP1 binding, which together limit ECT2 activity to a narrow zone at the cell equator. BRCT2-dependent control of active RhoA zone dimension functions in addition to the inhibitory signal of the astral microtubules. Our analysis provides detailed mechanistic insights into how ECT2 activity is regulated and how that regulation ensures, together with other signaling pathways, successful cell division.
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Affiliation(s)
- Sandra Schneid
- Department Biology II, Ludwig-Maximilians University, Planegg-Martinsried, Munich 82152, Germany
| | - Friederike Wolff
- Department Biology II, Ludwig-Maximilians University, Planegg-Martinsried, Munich 82152, Germany
| | - Kristina Buchner
- Department Biology II, Ludwig-Maximilians University, Planegg-Martinsried, Munich 82152, Germany
| | - Nils Bertram
- Department Biology II, Ludwig-Maximilians University, Planegg-Martinsried, Munich 82152, Germany
| | - Seren Baygün
- Department Biology II, Ludwig-Maximilians University, Planegg-Martinsried, Munich 82152, Germany
| | - Pedro Barbosa
- Department Biology II, Ludwig-Maximilians University, Planegg-Martinsried, Munich 82152, Germany
| | - Sriyash Mangal
- Department Biology II, Ludwig-Maximilians University, Planegg-Martinsried, Munich 82152, Germany
| | - Esther Zanin
- Department Biology II, Ludwig-Maximilians University, Planegg-Martinsried, Munich 82152, Germany.
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11
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Beaudet D, Pham N, Skaik N, Piekny A. Importin binding mediates the intramolecular regulation of anillin during cytokinesis. Mol Biol Cell 2020; 31:1124-1139. [PMID: 32238082 PMCID: PMC7353161 DOI: 10.1091/mbc.e20-01-0006] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Cytokinesis occurs by the ingression of an actomyosin ring that cleaves a cell into two daughters. This process is tightly controlled to avoid aneuploidy, and we previously showed that active Ran coordinates ring positioning with chromatin. Active Ran is high around chromatin, and forms an inverse gradient to cargo-bound importins. We found that the ring component anillin contains a nuclear localization signal (NLS) that binds to importin and is required for its function during cytokinesis. Here we reveal the mechanism whereby importin binding favors a conformation required for anillin's recruitment to the equatorial cortex. Active RhoA binds to the RhoA-binding domain causing an increase in accessibility of the nearby C2 domain containing the NLS. Importin binding subsequently stabilizes a conformation that favors interactions for cortical recruitment. In addition to revealing a novel mechanism for the importin-mediated regulation of a cortical protein, we also show how importin binding positively regulates protein function.
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Affiliation(s)
- Daniel Beaudet
- Department of Bioengineering, McGill University, Montreal, QC, Canada, H3A 0G4
| | - Nhat Pham
- Department of Biology, Concordia University, Montreal, QC, Canada, H4B 1R6
| | - Noha Skaik
- Department of Biology, Concordia University, Montreal, QC, Canada, H4B 1R6
| | - Alisa Piekny
- Department of Biology, Concordia University, Montreal, QC, Canada, H4B 1R6
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12
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Moon HM, Hippenmeyer S, Luo L, Wynshaw-Boris A. LIS1 determines cleavage plane positioning by regulating actomyosin-mediated cell membrane contractility. eLife 2020; 9:51512. [PMID: 32159512 PMCID: PMC7112955 DOI: 10.7554/elife.51512] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2019] [Accepted: 03/10/2020] [Indexed: 11/16/2022] Open
Abstract
Heterozygous loss of human PAFAH1B1 (coding for LIS1) results in the disruption of neurogenesis and neuronal migration via dysregulation of microtubule (MT) stability and dynein motor function/localization that alters mitotic spindle orientation, chromosomal segregation, and nuclear migration. Recently, human- induced pluripotent stem cell (iPSC) models revealed an important role for LIS1 in controlling the length of terminal cell divisions of outer radial glial (oRG) progenitors, suggesting cellular functions of LIS1 in regulating neural progenitor cell (NPC) daughter cell separation. Here, we examined the late mitotic stages NPCs in vivo and mouse embryonic fibroblasts (MEFs) in vitro from Pafah1b1-deficient mutants. Pafah1b1-deficient neocortical NPCs and MEFs similarly exhibited cleavage plane displacement with mislocalization of furrow-associated markers, associated with actomyosin dysfunction and cell membrane hyper-contractility. Thus, it suggests LIS1 acts as a key molecular link connecting MTs/dynein and actomyosin, ensuring that cell membrane contractility is tightly controlled to execute proper daughter cell separation.
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Affiliation(s)
- Hyang Mi Moon
- Department of Pediatrics, Institute for Human Genetics, Eli and Edythe Broad Center of Regenerative Medicine and Stem Cell Research, University of California, San Francisco, San Francisco, United States
| | - Simon Hippenmeyer
- Howard Hughes Medical Institute and Department of Biology, Stanford University, Stanford, United States
| | - Liqun Luo
- Howard Hughes Medical Institute and Department of Biology, Stanford University, Stanford, United States
| | - Anthony Wynshaw-Boris
- Department of Pediatrics, Institute for Human Genetics, Eli and Edythe Broad Center of Regenerative Medicine and Stem Cell Research, University of California, San Francisco, San Francisco, United States.,Department of Genetics and Genome Sciences, Case Western Reserve University, School of Medicine, Cleveland, United States
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13
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Estrem C, Moore JK. Help or hindrance: how do microtubule-based forces contribute to genome damage and repair? Curr Genet 2019; 66:303-311. [PMID: 31501990 DOI: 10.1007/s00294-019-01033-2] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2019] [Revised: 08/27/2019] [Accepted: 08/27/2019] [Indexed: 10/26/2022]
Abstract
Forces generated by molecular motors and the cytoskeleton move the nucleus and genome during many cellular processes, including cell migration and division. How these forces impact the genome, and whether cells regulate cytoskeletal forces to preserve genome integrity is unclear. We recently demonstrated that, in budding yeast, mutants that stabilize the microtubule cytoskeleton cause excessive movement of the mitotic spindle and nucleus. We found that increased nuclear movement results in DNA damage and increased time to repair the damage through homology-directed repair. Our results indicate that nuclear movement impairs DNA repair through increased tension on chromosomes and nuclear deformation. However, the previous studies have shown genome mobility, driven by cytoskeleton-based forces, aids in homology-directed DNA repair. This sets up an apparent paradox, where genome mobility may prevent or promote DNA repair. Hence, this review explores how the genome is affected by nuclear movement and how genome mobility could aid or hinder homology-directed repair.
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Affiliation(s)
- Cassi Estrem
- Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Jeffrey K Moore
- Department of Cell and Developmental Biology, University of Colorado School of Medicine, Aurora, CO, USA.
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14
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Centromere Dysfunction Compromises Mitotic Spindle Pole Integrity. Curr Biol 2019; 29:3072-3080.e5. [DOI: 10.1016/j.cub.2019.07.052] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2018] [Revised: 06/21/2019] [Accepted: 07/17/2019] [Indexed: 12/20/2022]
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15
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Estrem C, Moore JK. Astral microtubule forces alter nuclear organization and inhibit DNA repair in budding yeast. Mol Biol Cell 2019; 30:2000-2013. [PMID: 31067146 PMCID: PMC6727761 DOI: 10.1091/mbc.e18-12-0808] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/02/2022] Open
Abstract
Dividing cells must balance the maintenance of genome integrity with the generation of cytoskeletal forces that control chromosome position. In this study, we investigate how forces on astral microtubules impact the genome during cell division by using live-cell imaging of the cytoskeleton, chromatin, and DNA damage repair in budding yeast. Our results demonstrate that dynein-dependent forces on astral microtubules are propagated through the spindle during nuclear migration and when in excess can increase the frequency of double-stranded breaks (DSBs). Under these conditions, we find that homology-directed repair of DSBs is delayed, indicating antagonism between nuclear migration and the mechanism of homology-directed repair. These effects are partially rescued by mutants that weaken pericentric cohesion or mutants that decrease constriction on the nucleus as it moves through the bud neck. We propose that minimizing nuclear movement aids in finding a donor strand for homologous recombination.
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Affiliation(s)
- Cassi Estrem
- Department of Cell and Developmental Biology, University of Colorado School of Medicine, Aurora, CO 80045
| | - Jeffrey K Moore
- Department of Cell and Developmental Biology, University of Colorado School of Medicine, Aurora, CO 80045
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16
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Michaux JB, Robin FB, McFadden WM, Munro EM. Excitable RhoA dynamics drive pulsed contractions in the early C. elegans embryo. J Cell Biol 2018; 217:4230-4252. [PMID: 30275107 PMCID: PMC6279378 DOI: 10.1083/jcb.201806161] [Citation(s) in RCA: 74] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2018] [Revised: 08/30/2018] [Accepted: 09/05/2018] [Indexed: 12/17/2022] Open
Abstract
Pulsed actomyosin contractility underlies many morphogenetic processes. Here, Michaux et al. show that, in early C. elegans embryos, pulsed contractions are generated by intrinsically excitable RhoA dynamics, involving fast autoactivation of RhoA and delayed negative feedback through local actin-dependent recruitment of the RhoGAPs RGA-3/4. Pulsed actomyosin contractility underlies diverse modes of tissue morphogenesis, but the underlying mechanisms remain poorly understood. Here, we combined quantitative imaging with genetic perturbations to identify a core mechanism for pulsed contractility in early Caenorhabditis elegans embryos. We show that pulsed accumulation of actomyosin is governed by local control of assembly and disassembly downstream of RhoA. Pulsed activation and inactivation of RhoA precede, respectively, the accumulation and disappearance of actomyosin and persist in the absence of Myosin II. We find that fast (likely indirect) autoactivation of RhoA drives pulse initiation, while delayed, F-actin–dependent accumulation of the RhoA GTPase-activating proteins RGA-3/4 provides negative feedback to terminate each pulse. A mathematical model, constrained by our data, suggests that this combination of feedbacks is tuned to generate locally excitable RhoA dynamics. We propose that excitable RhoA dynamics are a common driver for pulsed contractility that can be tuned or coupled differently to actomyosin dynamics to produce a diversity of morphogenetic outcomes.
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Affiliation(s)
- Jonathan B Michaux
- Department of Molecular Genetics and Cell Biology, University of Chicago, Chicago, IL
| | - François B Robin
- Department of Molecular Genetics and Cell Biology, University of Chicago, Chicago, IL
| | | | - Edwin M Munro
- Department of Molecular Genetics and Cell Biology, University of Chicago, Chicago, IL .,Institute for Biophysical Dynamics, University of Chicago, Chicago, IL
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17
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McHugh T, Gluszek AA, Welburn JPI. Microtubule end tethering of a processive kinesin-8 motor Kif18b is required for spindle positioning. J Cell Biol 2018; 217:2403-2416. [PMID: 29661912 PMCID: PMC6028548 DOI: 10.1083/jcb.201705209] [Citation(s) in RCA: 47] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2017] [Revised: 11/22/2017] [Accepted: 03/29/2018] [Indexed: 11/22/2022] Open
Abstract
Mitotic spindle positioning specifies the plane of cell division during anaphase. Spindle orientation and positioning are therefore critical to ensure symmetric division in mitosis and asymmetric division during development. The control of astral microtubule length plays an essential role in positioning the spindle. In this study, using gene knockout, we show that the kinesin-8 Kif18b controls microtubule length to center the mitotic spindle at metaphase. Using in vitro reconstitution, we reveal that Kif18b is a highly processive plus end-directed motor that uses a C-terminal nonmotor microtubule-binding region to accumulate at growing microtubule plus ends. This region is regulated by phosphorylation to spatially control Kif18b accumulation at plus ends and is essential for Kif18b-dependent spindle positioning and regulation of microtubule length. Finally, we demonstrate that Kif18b shortens microtubules by increasing the catastrophe rate of dynamic microtubules. Overall, our work reveals that Kif18b uses its motile properties to reach microtubule ends, where it regulates astral microtubule length to ensure spindle centering.
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Affiliation(s)
- Toni McHugh
- Wellcome Trust Centre for Cell Biology, School of Biological Sciences, University of Edinburgh, Edinburgh, Scotland, UK
| | - Agata A Gluszek
- Wellcome Trust Centre for Cell Biology, School of Biological Sciences, University of Edinburgh, Edinburgh, Scotland, UK
| | - Julie P I Welburn
- Wellcome Trust Centre for Cell Biology, School of Biological Sciences, University of Edinburgh, Edinburgh, Scotland, UK
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18
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Okumura M, Natsume T, Kanemaki MT, Kiyomitsu T. Dynein-Dynactin-NuMA clusters generate cortical spindle-pulling forces as a multi-arm ensemble. eLife 2018; 7:36559. [PMID: 29848445 PMCID: PMC6037482 DOI: 10.7554/elife.36559] [Citation(s) in RCA: 90] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2018] [Accepted: 05/26/2018] [Indexed: 01/24/2023] Open
Abstract
To position the mitotic spindle within the cell, dynamic plus ends of astral microtubules are pulled by membrane-associated cortical force-generating machinery. However, in contrast to the chromosome-bound kinetochore structure, how the diffusion-prone cortical machinery is organized to generate large spindle-pulling forces remains poorly understood. Here, we develop a light-induced reconstitution system in human cells. We find that induced cortical targeting of NuMA, but not dynein, is sufficient for spindle pulling. This spindle-pulling activity requires dynein-dynactin recruitment by NuMA’s N-terminal long arm, dynein-based astral microtubule gliding, and NuMA’s direct microtubule-binding activities. Importantly, we demonstrate that cortical NuMA assembles specialized focal structures that cluster multiple force-generating modules to generate cooperative spindle-pulling forces. This clustering activity of NuMA is required for spindle positioning, but not for spindle-pole focusing. We propose that cortical Dynein-Dynactin-NuMA (DDN) clusters act as the core force-generating machinery that organizes a multi-arm ensemble reminiscent of the kinetochore. Almost every time a cell divides, it must share copies of its genetic material between two new daughter cells. A large molecular machine called the mitotic spindle makes this happen. The spindle is made of protein filaments known as microtubules that radiate out from two points at opposite ends of the cell. Some of these filaments attach to the genetic material in the center of the cell; some extend in the other direction and anchor the spindle to the cell membrane. The anchoring filaments – also known as astral microtubules – can position the mitotic spindle, which controls whether the cell splits straight down the middle (to give two identically sized cells) or off-center (which gives cells of different sizes). The force required to move the spindle comes from complexes of proteins under the cell membrane that contain a molecular motor called dynein, its partner dynactin, and three other proteins – including one called NuMA. The astral microtubules interact with this force-generating machinery, but it was unclear how these proteins are arranged at the membrane. One way to explore interactions in a protein complex is to use a light-induced reconstitution system. This technique involves molecules that will bind together whenever a light shines on them. Fusing these molecules with different proteins means that experimenters can control exactly where, and when, those proteins interact. Okumura et al. have now used a light-induced reconstitution system to understand how the force-generating machinery positions the spindle in human cells. One of the system’s molecules was fused to a protein located at the cell membrane; the other was fused to either the dynein motor or NuMA protein. Using light to move dynein around on the membrane did not move the spindle. Yet, changing the position of NuMA, by moving the light, was enough to rotate the spindle inside the cell. Understanding how these complexes of proteins work increases our understanding of how cells divide. Using the light-induced system to move the spindle could also reveal more about the role of symmetric and asymmetric cell division in organizing tissues. In particular, being able to manipulate the position and size of daughter cells will provide insight into how cell division shapes and maintains tissues during animal development.
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Affiliation(s)
- Masako Okumura
- Division of Biological Science, Graduate School of Science, Nagoya University, Nagoya, Japan
| | - Toyoaki Natsume
- Division of Molecular Cell Engineering, National Institute of Genetics, Research Organization of Information and Systems, Shizuoka, Japan.,Department of Genetics, SOKENDAI, Shizuoka, Japan
| | - Masato T Kanemaki
- Division of Molecular Cell Engineering, National Institute of Genetics, Research Organization of Information and Systems, Shizuoka, Japan.,Department of Genetics, SOKENDAI, Shizuoka, Japan
| | - Tomomi Kiyomitsu
- Division of Biological Science, Graduate School of Science, Nagoya University, Nagoya, Japan.,Precursory Research for Embryonic Science and Technology (PRESTO) Program, Japan Science and Technology Agency, Saitama, Japan
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19
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Jiang P, Zheng S, Lu L. Mitotic-Spindle Organizing Protein MztA Mediates Septation Signaling by Suppressing the Regulatory Subunit of Protein Phosphatase 2A-ParA in Aspergillus nidulans. Front Microbiol 2018; 9:988. [PMID: 29774021 PMCID: PMC5951981 DOI: 10.3389/fmicb.2018.00988] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2018] [Accepted: 04/27/2018] [Indexed: 12/20/2022] Open
Abstract
The proper timing and positioning of cytokinesis/septation is crucial for hyphal growth and conidiation in Aspergillus nidulans. The septation initiation network (SIN) components are a conserved spindle pole body (SPB) localized signaling cascade and the terminal kinase complex SidB-MobA, which must localize on the SPB in this pathway to trigger septation/cytokinesis. The regulatory subunit of phosphatase PP2A-ParA has been identified to be a negative regulator capable of inactivating the SIN. However, little is known about how ParA regulates the SIN pathway and whether ParA regulates the septum formation process through affecting the SPB-localized SIN proteins. In this study, through RNA-Seq and genetic approaches, we identified a new positive septation regulator, a putative mitotic-spindle organizing protein and a yeast Mzt1 homolog MztA, which acts antagonistically toward PP2A-ParA to coordinately regulate the SPB-localized SIN proteins SidB-MobA during septation. These findings imply that regulators, phosphatase PP2A-ParA and MztA counteract the septation function probably through balancing the polymerization and depolymerization of microtubules at the SPB.
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Affiliation(s)
- Ping Jiang
- Jiangsu Key Laboratory for Microbes and Functional Genomics, Jiangsu Engineering and Technology Research Center for Microbiology, College of Life Sciences, Nanjing Normal University, Nanjing, China
| | - Shujun Zheng
- Jiangsu Key Laboratory for Microbes and Functional Genomics, Jiangsu Engineering and Technology Research Center for Microbiology, College of Life Sciences, Nanjing Normal University, Nanjing, China
| | - Ling Lu
- Jiangsu Key Laboratory for Microbes and Functional Genomics, Jiangsu Engineering and Technology Research Center for Microbiology, College of Life Sciences, Nanjing Normal University, Nanjing, China
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20
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Benoit MPMH, Asenjo AB, Sosa H. Cryo-EM reveals the structural basis of microtubule depolymerization by kinesin-13s. Nat Commun 2018; 9:1662. [PMID: 29695795 PMCID: PMC5916938 DOI: 10.1038/s41467-018-04044-8] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2017] [Accepted: 03/27/2018] [Indexed: 11/25/2022] Open
Abstract
Kinesin-13s constitute a distinct group within the kinesin superfamily of motor proteins that promote microtubule depolymerization and lack motile activity. The molecular mechanism by which kinesin-13s depolymerize microtubules and are adapted to perform a seemingly very different activity from other kinesins is still unclear. To address this issue, here we report the near atomic resolution cryo-electron microscopy (cryo-EM) structures of Drosophila melanogaster kinesin-13 KLP10A protein constructs bound to curved or straight tubulin in different nucleotide states. These structures show how nucleotide induced conformational changes near the catalytic site are coupled with movement of the kinesin-13-specific loop-2 to induce tubulin curvature leading to microtubule depolymerization. The data highlight a modular structure that allows similar kinesin core motor-domains to be used for different functions, such as motility or microtubule depolymerization. Kinesin-13s are microtubule depolymerases that lack motile activity. Here the authors present the cryo-EM structures of kinesin-13 microtubule complexes in different nucleotide bound states, which reveal how ATP hydrolysis is linked to conformational changes and propose a model for kinesin induced depolymerisation.
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Affiliation(s)
- Matthieu P M H Benoit
- Department of Physiology and Biophysics, Albert Einstein College of Medicine, Bronx, NY, 10461, USA
| | - Ana B Asenjo
- Department of Physiology and Biophysics, Albert Einstein College of Medicine, Bronx, NY, 10461, USA
| | - Hernando Sosa
- Department of Physiology and Biophysics, Albert Einstein College of Medicine, Bronx, NY, 10461, USA.
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21
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Baudoin NC, Cimini D. A guide to classifying mitotic stages and mitotic defects in fixed cells. Chromosoma 2018; 127:215-227. [PMID: 29411093 DOI: 10.1007/s00412-018-0660-2] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2017] [Revised: 01/07/2018] [Accepted: 01/08/2018] [Indexed: 12/12/2022]
Abstract
Cell division is fundamental to life and its perturbation can disrupt organismal development, alter tissue homeostasis, and cause disease. Analysis of mitotic abnormalities provides insight into how certain perturbations affect the fidelity of cell division and how specific cellular structures, molecules, and enzymatic activities contribute to the accuracy of this process. However, accurate classification of mitotic defects is instrumental for correct interpretation of data and formulation of new hypotheses. In this article, we provide guidelines for identifying specific mitotic stages and for classifying normal and deviant mitotic phenotypes. We hope this will clarify confusion about how certain defects are classified and help investigators avoid misnomers, misclassification, and/or misinterpretation, thus leading to a unified and standardized system to classify mitotic defects.
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Affiliation(s)
- Nicolaas C Baudoin
- Department of Biological Sciences and Biocomplexity Institute, Virginia Tech, 1015 Life Science Circle, Blacksburg, VA, 24061, USA
| | - Daniela Cimini
- Department of Biological Sciences and Biocomplexity Institute, Virginia Tech, 1015 Life Science Circle, Blacksburg, VA, 24061, USA.
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22
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Zöllner SK, Selvanathan SP, Graham GT, Commins RMT, Hong SH, Moseley E, Parks S, Haladyna JN, Erkizan HV, Dirksen U, Hogarty MD, Üren A, Toretsky JA. Inhibition of the oncogenic fusion protein EWS-FLI1 causes G 2-M cell cycle arrest and enhanced vincristine sensitivity in Ewing's sarcoma. Sci Signal 2017; 10:10/499/eaam8429. [PMID: 28974650 DOI: 10.1126/scisignal.aam8429] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Ewing's sarcoma (ES) is a rare and highly malignant cancer that grows in the bones or surrounding tissues mostly affecting adolescents and young adults. A chimeric fusion between the RNA binding protein EWS and the ETS family transcription factor FLI1 (EWS-FLI1), which is generated from a chromosomal translocation, is implicated in driving most ES cases by modulation of transcription and alternative splicing. The small-molecule YK-4-279 inhibits EWS-FLI1 function and induces apoptosis in ES cells. We aimed to identify both the underlying mechanism of the drug and potential combination therapies that might enhance its antitumor activity. We tested 69 anticancer drugs in combination with YK-4-279 and found that vinca alkaloids exhibited synergy with YK-4-279 in five ES cell lines. The combination of YK-4-279 and vincristine reduced tumor burden and increased survival in mice bearing ES xenografts. We determined that independent drug-induced events converged to cause this synergistic therapeutic effect. YK-4-279 rapidly induced G2-M arrest, increased the abundance of cyclin B1, and decreased EWS-FLI1-mediated generation of microtubule-associated proteins, which rendered cells more susceptible to microtubule depolymerization by vincristine. YK-4-279 reduced the expression of the EWS-FLI1 target gene encoding the ubiquitin ligase UBE2C, which, in part, contributed to the increase in cyclin B1. YK-4-279 also increased the abundance of proapoptotic isoforms of MCL1 and BCL2, presumably through inhibition of alternative splicing by EWS-FLI1, thus promoting cell death in response to vincristine. Thus, a combination of vincristine and YK-4-279 might be therapeutically effective in ES patients.
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Affiliation(s)
- Stefan K Zöllner
- Department of Oncology and Pediatrics, Georgetown University, 3970 Reservoir Road Northwest, Washington, DC 20057, USA.,Department of Pediatric Hematology and Oncology, University Hospital Münster, Albert-Schweitzer-Campus 1, Gebäude A1, 48149 Münster, Germany
| | - Saravana P Selvanathan
- Department of Oncology and Pediatrics, Georgetown University, 3970 Reservoir Road Northwest, Washington, DC 20057, USA
| | - Garrett T Graham
- Department of Oncology and Pediatrics, Georgetown University, 3970 Reservoir Road Northwest, Washington, DC 20057, USA
| | - Ryan M T Commins
- Department of Oncology and Pediatrics, Georgetown University, 3970 Reservoir Road Northwest, Washington, DC 20057, USA
| | - Sung Hyeok Hong
- Department of Oncology and Pediatrics, Georgetown University, 3970 Reservoir Road Northwest, Washington, DC 20057, USA
| | - Eric Moseley
- Department of Oncology and Pediatrics, Georgetown University, 3970 Reservoir Road Northwest, Washington, DC 20057, USA
| | - Sydney Parks
- Department of Oncology and Pediatrics, Georgetown University, 3970 Reservoir Road Northwest, Washington, DC 20057, USA
| | - Jessica N Haladyna
- Department of Oncology and Pediatrics, Georgetown University, 3970 Reservoir Road Northwest, Washington, DC 20057, USA
| | - Hayriye V Erkizan
- Department of Oncology and Pediatrics, Georgetown University, 3970 Reservoir Road Northwest, Washington, DC 20057, USA
| | - Uta Dirksen
- Department of Pediatric Hematology and Oncology, University Hospital Münster, Albert-Schweitzer-Campus 1, Gebäude A1, 48149 Münster, Germany
| | - Michael D Hogarty
- Division of Oncology, Children's Hospital of Philadelphia, Colket Translational Research Building, Room 3020, 3501 Civic Center Boulevard, Philadelphia, PA 19014, USA
| | - Aykut Üren
- Department of Oncology and Pediatrics, Georgetown University, 3970 Reservoir Road Northwest, Washington, DC 20057, USA
| | - Jeffrey A Toretsky
- Department of Oncology and Pediatrics, Georgetown University, 3970 Reservoir Road Northwest, Washington, DC 20057, USA.
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23
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Landino J, Norris SR, Li M, Ballister ER, Lampson MA, Ohi R. Two mechanisms coordinate the recruitment of the chromosomal passenger complex to the plane of cell division. Mol Biol Cell 2017; 28:3634-3646. [PMID: 28954866 PMCID: PMC5706991 DOI: 10.1091/mbc.e17-06-0399] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2017] [Revised: 09/18/2017] [Accepted: 09/22/2017] [Indexed: 11/11/2022] Open
Abstract
Proper positioning of the chromosomal passenger complex (CPC) at the cell division plane is required for cytokinesis. We show here that CPC targeting to the equatorial cortex depends on both the kinesin MKlp2 and a direct interaction with actin. These recruitment mechanisms converge to promote successful cleavage furrow ingression. During cytokinesis, the chromosomal passenger complex (CPC) promotes midzone organization, specifies the cleavage plane, and regulates furrow contractility. The localizations of the CPC are coupled to its cytokinetic functions. At the metaphase-to-anaphase transition, the CPC dissociates from centromeres and localizes to midzone microtubules and the equatorial cortex. CPC relocalization to the cell middle is thought to depend on MKlp2-driven, plus end–directed transport. In support of this idea, MKlp2 depletion impairs cytokinesis; however, cytokinesis failure stems from furrow regression rather than failed initiation of furrowing. This suggests that an alternative mechanism(s) may concentrate the CPC at the division plane. We show here that direct actin binding, via the inner centromere protein (INCENP), enhances CPC enrichment at the equatorial cortex, thus acting in tandem with MKlp2. INCENP overexpression rescues furrowing in MKlp2-depleted cells in an INCENP-actin binding–dependent manner. Using live-cell imaging, we also find that MKlp2-dependent targeting of the CPC is biphasic. MKlp2 targets the CPC to the anti-parallel microtubule overlap of the midzone, after which the MKlp2-CPC complex moves in a nondirected manner. Collectively, our work suggests that both actin binding and MKlp2-dependent midzone targeting cooperate to precisely position the CPC during mitotic exit, and that these pathways converge to ensure successful cleavage furrow ingression.
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Affiliation(s)
- Jennifer Landino
- Department of Cell and Developmental Biology, Vanderbilt University Medical Center, Nashville, TN 37232
| | - Stephen R Norris
- Department of Cell and Developmental Biology, Vanderbilt University Medical Center, Nashville, TN 37232
| | - Muyi Li
- Department of Biology, University of Pennsylvania, Philadelphia, PA 19104
| | - Edward R Ballister
- Department of Biology, University of Pennsylvania, Philadelphia, PA 19104
| | - Michael A Lampson
- Department of Biology, University of Pennsylvania, Philadelphia, PA 19104
| | - Ryoma Ohi
- Department of Cell and Developmental Biology, Vanderbilt University Medical Center, Nashville, TN 37232 .,Department of Cell and Developmental Biology and Life Sciences Institute, University of Michigan Medical School, Ann Arbor, MI 48109
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24
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Chatterjee C, Benoit MPMH, DePaoli V, Diaz-Valencia JD, Asenjo AB, Gerfen GJ, Sharp DJ, Sosa H. Distinct Interaction Modes of the Kinesin-13 Motor Domain with the Microtubule. Biophys J 2016; 110:1593-1604. [PMID: 27074684 DOI: 10.1016/j.bpj.2016.02.029] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2015] [Revised: 01/28/2016] [Accepted: 02/16/2016] [Indexed: 01/12/2023] Open
Abstract
Kinesins-13s are members of the kinesin superfamily of motor proteins that depolymerize microtubules (MTs) and have no motile activity. Instead of generating unidirectional movement over the MT lattice, like most other kinesins, kinesins-13s undergo one-dimensional diffusion (ODD) and induce depolymerization at the MT ends. To understand the mechanism of ODD and the origin of the distinct kinesin-13 functionality, we used ensemble and single-molecule fluorescence polarization microscopy to analyze the behavior and conformation of Drosophila melanogaster kinesin-13 KLP10A protein constructs bound to the MT lattice. We found that KLP10A interacts with the MT in two coexisting modes: one in which the motor domain binds with a specific orientation to the MT lattice and another where the motor domain is very mobile and able to undergo ODD. By comparing the orientation and dynamic behavior of mutated and deletion constructs we conclude that 1) the Kinesin-13 class specific neck domain and loop-2 help orienting the motor domain relative to the MT. 2) During ODD the KLP10A motor-domain changes orientation rapidly (rocks or tumbles). 3) The motor domain alone is capable of undergoing ODD. 4) A second tubulin binding site in the KLP10A motor domain is not critical for ODD. 5) The neck domain is not the element preventing KLP10A from binding to the MT lattice like motile kinesins.
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Affiliation(s)
- Chandrima Chatterjee
- Departments of Physiology and Biophysics, Albert Einstein College of Medicine, Bronx, New York
| | - Matthieu P M H Benoit
- Departments of Physiology and Biophysics, Albert Einstein College of Medicine, Bronx, New York
| | - Vania DePaoli
- Departments of Physiology and Biophysics, Albert Einstein College of Medicine, Bronx, New York
| | - Juan D Diaz-Valencia
- Departments of Physiology and Biophysics, Albert Einstein College of Medicine, Bronx, New York
| | - Ana B Asenjo
- Departments of Physiology and Biophysics, Albert Einstein College of Medicine, Bronx, New York
| | - Gary J Gerfen
- Departments of Physiology and Biophysics, Albert Einstein College of Medicine, Bronx, New York
| | - David J Sharp
- Departments of Physiology and Biophysics, Albert Einstein College of Medicine, Bronx, New York
| | - Hernando Sosa
- Departments of Physiology and Biophysics, Albert Einstein College of Medicine, Bronx, New York.
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25
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Zhao J, Wang Q. Modeling cytokinesis of eukaryotic cells driven by the actomyosin contractile ring. INTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN BIOMEDICAL ENGINEERING 2016; 32. [PMID: 26891069 DOI: 10.1002/cnm.2774] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/11/2015] [Revised: 02/11/2016] [Accepted: 02/12/2016] [Indexed: 06/05/2023]
Abstract
A three-dimensional (3D) hydrodynamic model for cytokinesis of eukaryotic cells is developed, in which we model dynamics of actomyosins in the cell cortex, in particular, along the cytokinetic ring formed in the cortex and in the neighborhood of the cell's division plane explicitly. Specifically, the active force actuated by the actomyosin's activity along the cytokinetic ring is modeled by a surface force whose strength is proportional to the actomyosin concentration while the cell morphology is tracked by a phase field model. The model is then solved in 3D space and time using a finite difference method on graphic processing units. Dynamical morphological patterns of eukaryotic cells during cytokinesis are numerically simulated with the model. These simulated morphological patterns agree quantitatively with experimental observations. Copyright © 2016 John Wiley & Sons, Ltd.
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Affiliation(s)
- Jia Zhao
- Department of Mathematics, University of South Carolina, Columbia, 29028, SC, USA
| | - Qi Wang
- Department of Mathematics, Interdisciplinary Mathematics Institute and NanoCenter at USC, University of South Carolina, Columbia, SC 29028; School of Mathematical Sciences, Nankai University, Tianjin, China 300071; Beijing Computational Science Research Center, Beijing, China 100193
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26
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Bendre S, Rondelet A, Hall C, Schmidt N, Lin YC, Brouhard GJ, Bird AW. GTSE1 tunes microtubule stability for chromosome alignment and segregation by inhibiting the microtubule depolymerase MCAK. J Cell Biol 2016; 215:631-647. [PMID: 27881713 PMCID: PMC5147003 DOI: 10.1083/jcb.201606081] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2016] [Revised: 10/04/2016] [Accepted: 10/21/2016] [Indexed: 12/21/2022] Open
Abstract
The microtubule depolymerase MCAK influences chromosomal instability (CIN), but what controls its activity remains unclear. Bendre et al. show that GTSE1, a protein found overexpressed in tumors, regulates microtubule stability and chromosome alignment during mitosis by inhibiting MCAK. High levels of GTSE1 are linked to chromosome missegregation and CIN. The dynamic regulation of microtubules (MTs) during mitosis is critical for accurate chromosome segregation and genome stability. Cancer cell lines with hyperstabilized kinetochore MTs have increased segregation errors and elevated chromosomal instability (CIN), but the genetic defects responsible remain largely unknown. The MT depolymerase MCAK (mitotic centromere-associated kinesin) can influence CIN through its impact on MT stability, but how its potent activity is controlled in cells remains unclear. In this study, we show that GTSE1, a protein found overexpressed in aneuploid cancer cell lines and tumors, regulates MT stability during mitosis by inhibiting MCAK MT depolymerase activity. Cells lacking GTSE1 have defects in chromosome alignment and spindle positioning as a result of MT instability caused by excess MCAK activity. Reducing GTSE1 levels in CIN cancer cell lines reduces chromosome missegregation defects, whereas artificially inducing GTSE1 levels in chromosomally stable cells elevates chromosome missegregation and CIN. Thus, GTSE1 inhibition of MCAK activity regulates the balance of MT stability that determines the fidelity of chromosome alignment, segregation, and chromosomal stability.
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Affiliation(s)
- Shweta Bendre
- Max Planck Institute of Molecular Physiology, 44227 Dortmund, Germany
| | - Arnaud Rondelet
- Max Planck Institute of Molecular Physiology, 44227 Dortmund, Germany
| | - Conrad Hall
- Department of Biology, McGill University, Montreal H3A 1B1, Quebec, Canada
| | - Nadine Schmidt
- Max Planck Institute of Molecular Physiology, 44227 Dortmund, Germany
| | - Yu-Chih Lin
- Max Planck Institute of Molecular Physiology, 44227 Dortmund, Germany
| | - Gary J Brouhard
- Department of Biology, McGill University, Montreal H3A 1B1, Quebec, Canada
| | - Alexander W Bird
- Max Planck Institute of Molecular Physiology, 44227 Dortmund, Germany
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27
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Po'uha ST, Kavallaris M. Gamma-actin is involved in regulating centrosome function and mitotic progression in cancer cells. Cell Cycle 2016; 14:3908-19. [PMID: 26697841 DOI: 10.1080/15384101.2015.1120920] [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] [Indexed: 12/24/2022] Open
Abstract
Reorganization of the actin cytoskeleton during mitosis is crucial for regulating cell division. A functional role for γ-actin in mitotic arrest induced by the microtubule-targeted agent, paclitaxel, has recently been demonstrated. We hypothesized that γ-actin plays a role in mitosis. Herein, we investigated the effect of γ-actin in mitosis and demonstrated that γ-actin is important in the distribution of β-actin and formation of actin-rich retraction fibers during mitosis. The reduced ability of paclitaxel to induce mitotic arrest as a result of γ-actin depletion was replicated with a range of mitotic inhibitors, suggesting that γ-actin loss reduces the ability of broad classes of anti-mitotic agents to induce mitotic arrest. In addition, partial depletion of γ-actin enhanced centrosome amplification in cancer cells and caused a significant delay in prometaphase/metaphase. This prolonged prometaphase/metaphase arrest was due to mitotic defects such as uncongressed and missegregated chromosomes, and correlated with an increased presence of mitotic spindle abnormalities in the γ-actin depleted cells. Collectively, these results demonstrate a previously unknown role for γ-actin in regulating centrosome function, chromosome alignment and maintenance of mitotic spindle integrity.
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Affiliation(s)
- Sela T Po'uha
- a Children's Cancer Institute; Lowy Cancer Research Center; University of New South Wales ; Randwick , NSW , Australia
| | - Maria Kavallaris
- a Children's Cancer Institute; Lowy Cancer Research Center; University of New South Wales ; Randwick , NSW , Australia.,b ARC Center of Excellence in Convergent Bio-Nano Science and Technology; Australian Center for Nanomedicine; University of New South Wales ; Sydney , Australia
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28
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van Heesbeen RGHP, Raaijmakers JA, Tanenbaum ME, Halim VA, Lelieveld D, Lieftink C, Heck AJR, Egan DA, Medema RH. Aurora A, MCAK, and Kif18b promote Eg5-independent spindle formation. Chromosoma 2016; 126:473-486. [PMID: 27354041 PMCID: PMC5509784 DOI: 10.1007/s00412-016-0607-4] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2016] [Revised: 06/19/2016] [Accepted: 06/21/2016] [Indexed: 11/28/2022]
Abstract
Inhibition of the microtubule (MT) motor protein Eg5 results in a mitotic arrest due to the formation of monopolar spindles, making Eg5 an attractive target for anti-cancer therapies. However, Eg5-independent pathways for bipolar spindle formation exist, which might promote resistance to treatment with Eg5 inhibitors. To identify essential components for Eg5-independent bipolar spindle formation, we performed a genome-wide siRNA screen in Eg5-independent cells (EICs). We find that the kinase Aurora A and two kinesins, MCAK and Kif18b, are essential for bipolar spindle assembly in EICs and in cells with reduced Eg5 activity. Aurora A promotes bipolar spindle assembly by phosphorylating Kif15, hereby promoting Kif15 localization to the spindle. In turn, MCAK and Kif18b promote bipolar spindle assembly by destabilizing the astral MTs. One attractive way to interpret our data is that, in the absence of MCAK and Kif18b, excessive astral MTs generate inward pushing forces on centrosomes at the cortex that inhibit centrosome separation. Together, these data suggest a novel function for astral MTs in force generation on spindle poles and how proteins involved in regulating microtubule length can contribute to bipolar spindle assembly.
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Affiliation(s)
| | - Jonne A Raaijmakers
- Division of Cell Biology, The Netherlands Cancer Institute, Amsterdam, The Netherlands
| | - Marvin E Tanenbaum
- Hubrecht Institute, The Royal Netherlands Academy of Arts and Sciences (KNAW) and University Medical Center Utrecht, Utrecht, the Netherlands
| | - Vincentius A Halim
- Division of Cell Biology, The Netherlands Cancer Institute, Amsterdam, The Netherlands.,Biomolecular Mass Spectrometry and Proteomics Group, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, Utrecht University, Utrecht, The Netherlands
| | - Daphne Lelieveld
- Cell Screening Core, Department of Cell Biology, Center for Molecular Medicine, University Medical Centre, Utrecht, The Netherlands
| | - Cor Lieftink
- Division of Molecular Carcinogenesis, The Netherlands Cancer Institute, Amsterdam, The Netherlands
| | - Albert J R Heck
- Biomolecular Mass Spectrometry and Proteomics Group, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, Utrecht University, Utrecht, The Netherlands
| | - David A Egan
- Cell Screening Core, Department of Cell Biology, Center for Molecular Medicine, University Medical Centre, Utrecht, The Netherlands
| | - René H Medema
- Division of Cell Biology, The Netherlands Cancer Institute, Amsterdam, The Netherlands.
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29
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An Overview of Alternating Electric Fields Therapy (NovoTTF Therapy) for the Treatment of Malignant Glioma. Curr Neurol Neurosci Rep 2016; 16:8. [PMID: 26739692 PMCID: PMC4703612 DOI: 10.1007/s11910-015-0606-5] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
As with many cancer treatments, tumor treating fields (TTFields) target rapidly dividing tumor cells. During mitosis, TTFields-exposed cells exhibit uncontrolled membrane blebbing at the onset of anaphase, resulting in aberrant mitotic exit. Based on these criteria, at least two protein complexes have been proposed as TTFields’ molecular targets, including α/β-tubulin and the septin 2, 6, 7 heterotrimer. After aberrant mitotic exit, cells exhibited abnormal nuclei and signs of cellular stress, including decreased cellular proliferation and p53 dependence, and exhibit the hallmarks of immunogenic cell death, suggesting that TTFields treatment may induce an antitumor immune response. Clinical trials lead to Food and Drug Administration approval for their treatment of recurrent glioblastoma. Detailed modeling of TTFields within the brain suggests that the location of the tumor may affect treatment efficacy. These observations have a profound impact on the use of TTFields in the clinic, including what co-therapies may be best applied to boost its efficacy.
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30
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Mishima M. Centralspindlin in Rappaport’s cleavage signaling. Semin Cell Dev Biol 2016; 53:45-56. [DOI: 10.1016/j.semcdb.2016.03.006] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2015] [Accepted: 03/02/2016] [Indexed: 02/07/2023]
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31
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Uehara R, Kamasaki T, Hiruma S, Poser I, Yoda K, Yajima J, Gerlich DW, Goshima G. Augmin shapes the anaphase spindle for efficient cytokinetic furrow ingression and abscission. Mol Biol Cell 2016; 27:812-27. [PMID: 26764096 PMCID: PMC4803307 DOI: 10.1091/mbc.e15-02-0101] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2015] [Revised: 01/05/2016] [Accepted: 01/07/2016] [Indexed: 11/11/2022] Open
Abstract
During anaphase, distinct populations of microtubules (MTs) form by either centrosome-dependent or augmin-dependent nucleation. It remains largely unknown whether these different MT populations contribute distinct functions to cytokinesis. Here we show that augmin-dependent MTs are required for the progression of both furrow ingression and abscission. Augmin depletion reduced the accumulation of anillin, a contractile ring regulator at the cell equator, yet centrosomal MTs were sufficient to mediate RhoA activation at the furrow. This defect in contractile ring organization, combined with incomplete spindle pole separation during anaphase, led to impaired furrow ingression. During the late stages of cytokinesis, astral MTs formed bundles in the intercellular bridge, but these failed to assemble a focused midbody structure and did not establish tight linkage to the plasma membrane, resulting in furrow regression. Thus augmin-dependent acentrosomal MTs and centrosomal MTs contribute to nonredundant targeting mechanisms of different cytokinesis factors, which are required for the formation of a functional contractile ring and midbody.
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Affiliation(s)
- Ryota Uehara
- Creative Research Institution, Hokkaido University, Sapporo 001-0021, Japan Department of Life Sciences, School of Arts and Sciences, University of Tokyo, Tokyo 153-8902, Japan Division of Biological Science, Graduate School of Science, Nagoya University, Nagoya 464-8602, Japan
| | - Tomoko Kamasaki
- Division of Biological Science, Graduate School of Science, Nagoya University, Nagoya 464-8602, Japan
| | - Shota Hiruma
- Creative Research Institution, Hokkaido University, Sapporo 001-0021, Japan
| | - Ina Poser
- Max Planck Institute of Molecular Cell Biology and Genetics, 01307 Dresden, Germany
| | - Kinya Yoda
- Division of Biological Science, Graduate School of Science, Nagoya University, Nagoya 464-8602, Japan
| | - Junichiro Yajima
- Department of Life Sciences, School of Arts and Sciences, University of Tokyo, Tokyo 153-8902, Japan
| | - Daniel W Gerlich
- Institute of Molecular Biotechnology of the Austrian Academy of Sciences, Vienna Biocenter Campus, 1030 Vienna, Austria
| | - Gohta Goshima
- Division of Biological Science, Graduate School of Science, Nagoya University, Nagoya 464-8602, Japan
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32
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de Castro IJ, Gokhan E, Vagnarelli P. Resetting a functional G1 nucleus after mitosis. Chromosoma 2016; 125:607-19. [PMID: 26728621 PMCID: PMC5023730 DOI: 10.1007/s00412-015-0561-6] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2015] [Accepted: 11/13/2015] [Indexed: 12/21/2022]
Abstract
The maintenance of the correct cellular information goes beyond the simple transmission of an intact genetic code from one generation to the next. Epigenetic changes, topological cues and correct protein-protein interactions need to be re-established after each cell division to allow the next cell cycle to resume in the correct regulated manner. This process begins with mitotic exit and re-sets all the changes that occurred during mitosis thus restoring a functional G1 nucleus in preparation for the next cell cycle. Mitotic exit is triggered by inactivation of mitotic kinases and the reversal of their phosphorylation activities on many cellular components, from nuclear lamina to transcription factors and chromatin itself. To reverse all these phosphorylations, phosphatases act during mitotic exit in a timely and spatially controlled manner directing the events that lead to a functional G1 nucleus. In this review, we will summarise the recent developments on the control of phosphatases and their known substrates during mitotic exit, and the key steps that control the restoration of chromatin status, nuclear envelope reassembly and nuclear body re-organisation. Although pivotal work has been conducted in this area in yeast, due to differences between the mitotic exit network between yeast and vertebrates, we will mainly concentrate on the vertebrate system.
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Affiliation(s)
- Ines J de Castro
- College of Health and Life Science, Research Institute of Environment Health and Society, Brunel University London, Uxbridge, UB8 3PH, UK
| | - Ezgi Gokhan
- College of Health and Life Science, Research Institute of Environment Health and Society, Brunel University London, Uxbridge, UB8 3PH, UK
| | - Paola Vagnarelli
- College of Health and Life Science, Research Institute of Environment Health and Society, Brunel University London, Uxbridge, UB8 3PH, UK.
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33
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Cytoskeletal Symmetry Breaking and Chirality: From Reconstituted Systems to Animal Development. Symmetry (Basel) 2015. [DOI: 10.3390/sym7042062] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
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Abstract
A metaphase spindle is a complex structure consisting of microtubules and a myriad of different proteins that modulate microtubule dynamics together with chromatin and kinetochores. A decade ago, a full description of spindle formation and function seemed a lofty goal. Here, we describe how work in the last 10 years combining cataloging of spindle components, the characterization of their biochemical activities using single-molecule techniques, and theory have advanced our knowledge. Taken together, these advances suggest that a full understanding of spindle assembly and function may soon be possible.
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Affiliation(s)
- Simone Reber
- Max Planck Institute of Molecular Cell Biology and Genetics, 01307 Dresden, Germany Integrative Research Institute (IRI) for the Life Sciences, Humboldt-Universität zu Berlin, 10115 Berlin, Germany
| | - Anthony A Hyman
- Max Planck Institute of Molecular Cell Biology and Genetics, 01307 Dresden, Germany
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35
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Mitosis, microtubule dynamics and the evolution of kinesins. Exp Cell Res 2015; 334:61-9. [PMID: 25708751 DOI: 10.1016/j.yexcr.2015.02.010] [Citation(s) in RCA: 58] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2015] [Accepted: 02/10/2015] [Indexed: 12/20/2022]
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36
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Nawaz M, Camussi G, Valadi H, Nazarenko I, Ekström K, Wang X, Principe S, Shah N, Ashraf NM, Fatima F, Neder L, Kislinger T. The emerging role of extracellular vesicles as biomarkers for urogenital cancers. Nat Rev Urol 2014; 11:688-701. [PMID: 25403245 DOI: 10.1038/nrurol.2014.301] [Citation(s) in RCA: 224] [Impact Index Per Article: 22.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
The knowledge gained from comprehensive profiling projects that aim to define the complex genomic alterations present within cancers will undoubtedly improve our ability to detect and treat those diseases, but the influence of these resources on our understanding of basic cancer biology is still to be demonstrated. Extracellular vesicles have gained considerable attention in past years, both as mediators of intercellular signalling and as potential sources for the discovery of novel cancer biomarkers. In general, research on extracellular vesicles investigates either the basic mechanism of vesicle formation and cargo incorporation, or the isolation of vesicles from available body fluids for biomarker discovery. A deeper understanding of the cargo molecules present in extracellular vesicles obtained from patients with urogenital cancers, through high-throughput proteomics or genomics approaches, will aid in the identification of novel diagnostic and prognostic biomarkers, and can potentially lead to the discovery of new therapeutic targets.
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Affiliation(s)
| | | | - Hadi Valadi
- BIOMATCELL VINN Excellence Center of Biomaterials and Cell Therapy, University of Gothenburg, Sweden
| | | | - Karin Ekström
- BIOMATCELL VINN Excellence Center of Biomaterials and Cell Therapy, University of Gothenburg, Sweden
| | - Xiaoqin Wang
- BIOMATCELL VINN Excellence Center of Biomaterials and Cell Therapy, University of Gothenburg, Sweden
| | - Simona Principe
- Princess Margaret Cancer Center, 101 College Street, TMDT 9-807, Toronto, ON M5G 1L7, Canada
| | | | | | | | | | - Thomas Kislinger
- Princess Margaret Cancer Center, 101 College Street, TMDT 9-807, Toronto, ON M5G 1L7, Canada
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37
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Tanenbaum ME, Medema RH, Akhmanova A. Regulation of localization and activity of the microtubule depolymerase MCAK. BIOARCHITECTURE 2014; 1:80-87. [PMID: 21866268 DOI: 10.4161/bioa.1.2.15807] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/05/2011] [Accepted: 04/09/2011] [Indexed: 12/29/2022]
Abstract
Mitotic Centromere Associated Kinesin (MCAK) is a potent microtubule depolymerizing and catastrophe-inducing factor, which uses the energy of ATP hydrolysis to destabilize microtubule ends. MCAK is localized to inner centromeres, kinetochores and spindle poles of mitotic cells, and is also present in the cytoplasm. Both in interphase and in mitosis, MCAK can specifically accumulate at the growing microtubule ends. Here we discuss the mechanisms, which modulate subcellular localization and activity of MCAK through the interaction with the End Binding (EB) proteins and phosphorylation.
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Affiliation(s)
- Marvin E Tanenbaum
- Department of Medical Oncology and Cancer Genomics Center; University Medical Center; Utrecht, The Netherlands
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38
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Ferreira JG, Pereira AL, Maiato H. Microtubule plus-end tracking proteins and their roles in cell division. INTERNATIONAL REVIEW OF CELL AND MOLECULAR BIOLOGY 2014; 309:59-140. [PMID: 24529722 DOI: 10.1016/b978-0-12-800255-1.00002-8] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Microtubules are cellular components that are required for a variety of essential processes such as cell motility, mitosis, and intracellular transport. This is possible because of the inherent dynamic properties of microtubules. Many of these properties are tightly regulated by a number of microtubule plus-end-binding proteins or +TIPs. These proteins recognize the distal end of microtubules and are thus in the right context to control microtubule dynamics. In this review, we address how microtubule dynamics are regulated by different +TIP families, focusing on how functionally diverse +TIPs spatially and temporally regulate microtubule dynamics during animal cell division.
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Affiliation(s)
- Jorge G Ferreira
- Chromosome Instability & Dynamics Laboratory, Instituto de Biologia Molecular e Celular, University of Porto, Porto, Portugal; Cell Division Unit, Department of Experimental Biology, University of Porto, Porto, Portugal
| | - Ana L Pereira
- Chromosome Instability & Dynamics Laboratory, Instituto de Biologia Molecular e Celular, University of Porto, Porto, Portugal
| | - Helder Maiato
- Chromosome Instability & Dynamics Laboratory, Instituto de Biologia Molecular e Celular, University of Porto, Porto, Portugal; Cell Division Unit, Department of Experimental Biology, University of Porto, Porto, Portugal.
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39
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Turlier H, Audoly B, Prost J, Joanny JF. Furrow constriction in animal cell cytokinesis. Biophys J 2014; 106:114-23. [PMID: 24411243 DOI: 10.1016/j.bpj.2013.11.014] [Citation(s) in RCA: 108] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2013] [Revised: 11/08/2013] [Accepted: 11/11/2013] [Indexed: 10/25/2022] Open
Abstract
Cytokinesis is the process of physical cleavage at the end of cell division; it proceeds by ingression of an acto-myosin furrow at the equator of the cell. Its failure leads to multinucleated cells and is a possible cause of tumorigenesis. Here, we calculate the full dynamics of furrow ingression and predict cytokinesis completion above a well-defined threshold of equatorial contractility. The cortical acto-myosin is identified as the main source of mechanical dissipation and active forces. Thereupon, we propose a viscous active nonlinear membrane theory of the cortex that explicitly includes actin turnover and where the active RhoA signal leads to an equatorial band of myosin overactivity. The resulting cortex deformation is calculated numerically, and reproduces well the features of cytokinesis such as cell shape and cortical flows toward the equator. Our theory gives a physical explanation of the independence of cytokinesis duration on cell size in embryos. It also predicts a critical role of turnover on the rate and success of furrow constriction. Scaling arguments allow for a simple interpretation of the numerical results and unveil the key mechanism that generates the threshold for cytokinesis completion: cytoplasmic incompressibility results in a competition between the furrow line tension and the cell poles' surface tension.
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Affiliation(s)
- Hervé Turlier
- Physicochimie Curie (Centre National de la Recherche Scientifique-UMR168), Institut Curie, Section de Recherche, Paris, France.
| | - Basile Audoly
- Institut Jean Le Rond d'Alembert (Centre National de la Recherche Scientifique-UMR7190), Université Pierre-et-Marie-Curie, Université Paris VI, Paris, France
| | - Jacques Prost
- Physicochimie Curie (Centre National de la Recherche Scientifique-UMR168), Institut Curie, Section de Recherche, Paris, France; École Supérieure de Physique et de Chimie Industrielles de la Ville de Paris-ParisTech, Paris, France
| | - Jean-François Joanny
- Physicochimie Curie (Centre National de la Recherche Scientifique-UMR168), Institut Curie, Section de Recherche, Paris, France
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40
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van Oostende Triplet C, Jaramillo Garcia M, Haji Bik H, Beaudet D, Piekny A. Anillin interacts with microtubules and is part of the astral pathway that defines cortical domains. J Cell Sci 2014; 127:3699-710. [DOI: 10.1242/jcs.147504] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
Cytokinesis occurs by the ingression of an actomyosin ring that separates the cell into two daughter cells. The mitotic spindle, comprised of astral and central spindle microtubules, couples contractile ring ingression with DNA segregation. Cues from the central spindle activate RhoA, the upstream regulator of the contractile ring. However, additional cues from the astral microtubules also reinforce the localization of active RhoA. Using human cells, we show that astral and central spindle microtubules independently control the localization of contractile proteins during cytokinesis. Astral microtubules restrict the accumulation and localization of contractile proteins during mitosis, while the central spindle forms a discrete ring by directing RhoA activation in the equatorial plane. Anillin stabilizes the contractile ring during cytokinesis. We show that human anillin interacts with astral microtubules, which is competed by its cortical recruitment by active RhoA. Anillin restricts the localization of myosin at the equatorial cortex, and NuMA (part of the microtubule-tethering complex that regulates spindle position) at the polar cortex. The sequestration of anillin by astral microtubules may alter the organization of cortical proteins to polarize cells for cytokinesis.
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41
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Nawaz M, Fatima F, Zanetti BR, Martins IDL, Schiavotelo NL, Mendes ND, Silvestre RN, Neder L. Microvesicles in Gliomas and Medulloblastomas: An Overview. ACTA ACUST UNITED AC 2014. [DOI: 10.4236/jct.2014.52023] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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42
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Uehara R, Tsukada Y, Kamasaki T, Poser I, Yoda K, Gerlich DW, Goshima G. Aurora B and Kif2A control microtubule length for assembly of a functional central spindle during anaphase. ACTA ACUST UNITED AC 2013; 202:623-36. [PMID: 23960144 PMCID: PMC3747305 DOI: 10.1083/jcb.201302123] [Citation(s) in RCA: 60] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
A gradient of Aurora B activity determines the distribution of the microtubule depolymerase Kif2A at the central spindle and specifies the subsequent spindle structure necessary for proper cytokinesis. The central spindle is built during anaphase by coupling antiparallel microtubules (MTs) at a central overlap zone, which provides a signaling scaffold for the regulation of cytokinesis. The mechanisms underlying central spindle morphogenesis are still poorly understood. In this paper, we show that the MT depolymerase Kif2A controls the length and alignment of central spindle MTs through depolymerization at their minus ends. The distribution of Kif2A was limited to the distal ends of the central spindle through Aurora B–dependent phosphorylation and exclusion from the spindle midzone. Overactivation or inhibition of Kif2A affected interchromosomal MT length and disorganized the central spindle, resulting in uncoordinated cell division. Experimental data and model simulations suggest that the steady-state length of the central spindle and its symmetric position between segregating chromosomes are predominantly determined by the Aurora B activity gradient. On the basis of these results, we propose a robust self-organization mechanism for central spindle formation.
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Affiliation(s)
- Ryota Uehara
- Division of Biological Science, Graduate School of Science, Nagoya University, Chikusa-ku, Nagoya 464-8602, Japan.
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43
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Zanin E, Desai A, Poser I, Toyoda Y, Andree C, Moebius C, Bickle M, Conradt B, Piekny A, Oegema K. A conserved RhoGAP limits M phase contractility and coordinates with microtubule asters to confine RhoA during cytokinesis. Dev Cell 2013; 26:496-510. [PMID: 24012485 DOI: 10.1016/j.devcel.2013.08.005] [Citation(s) in RCA: 76] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2012] [Revised: 05/22/2013] [Accepted: 08/07/2013] [Indexed: 12/27/2022]
Abstract
During animal cell cytokinesis, the spindle directs contractile ring assembly by activating RhoA in a narrow equatorial zone. Rapid GTPase activating protein (GAP)-mediated inactivation (RhoA flux) is proposed to limit RhoA zone dimensions. Testing the significance of RhoA flux has been hampered by the fact that the GAP targeting RhoA is not known. Here, we identify M phase GAP (MP-GAP) as the primary GAP targeting RhoA during mitosis and cytokinesis. MP-GAP inhibition caused excessive RhoA activation in M phase, leading to the uncontrolled formation of large cortical protrusions and late cytokinesis failure. RhoA zone width was broadened by attenuation of the centrosomal asters but was not affected by MP-GAP inhibition alone. Simultaneous aster attenuation and MP-GAP inhibition led to RhoA accumulation around the entire cell periphery. These results identify the major GAP restraining RhoA during cell division and delineate the relative contributions of RhoA flux and centrosomal asters in controlling RhoA zone dimensions.
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Affiliation(s)
- Esther Zanin
- Department of Cellular and Molecular Medicine, Ludwig Institute for Cancer Research, University of California, San Diego, La Jolla, CA 92093, USA; Center for Integrated Protein Science CIPSM, Department Biology II, Ludwig-Maximilians University, Munich, 82152 Planegg-Martinsried, Germany
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44
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A second tubulin binding site on the kinesin-13 motor head domain is important during mitosis. PLoS One 2013; 8:e73075. [PMID: 24015286 PMCID: PMC3755979 DOI: 10.1371/journal.pone.0073075] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2013] [Accepted: 07/15/2013] [Indexed: 01/03/2023] Open
Abstract
Kinesin-13s are microtubule (MT) depolymerases different from most other kinesins that move along MTs. Like other kinesins, they have a motor or head domain (HD) containing a tubulin and an ATP binding site. Interestingly, kinesin-13s have an additional binding site (Kin-Tub-2) on the opposite side of the HD that contains several family conserved positively charged residues. The role of this site in kinesin-13 function is not clear. To address this issue, we investigated the in-vitro and in-vivo effects of mutating Kin-Tub-2 family conserved residues on the Drosophila melanogaster kinesin-13, KLP10A. We show that the Kin-Tub-2 site enhances tubulin cross-linking and MT bundling properties of KLP10A in-vitro. Disruption of the Kin-Tub-2 site, despite not having a deleterious effect on MT depolymerization, results in abnormal mitotic spindles and lagging chromosomes during mitosis in Drosophila S2 cells. The results suggest that the additional Kin-Tub-2 tubulin biding site plays a direct MT attachment role in-vivo.
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45
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Abstract
The microtubule (MT) cytoskeleton supports a broad range of cellular functions, from providing tracks for intracellular transport, to supporting movement of cilia and flagella, to segregating chromosomes in mitosis. These functions are facilitated by the organizational and dynamic plasticity of MT networks. An important class of enzymes that alters MT dynamics is the depolymerizing kinesin-like proteins, which use their catalytic activities to regulate MT end dynamics. In this review, we discuss four topics surrounding these MT-depolymerizing kinesins. We provide a historical overview of studies focused on these motors and discuss their phylogeny. In the second half, we discuss their enzymology and biophysics and give an overview of their known cellular functions. This discussion highlights the fact that MT-depolymerizing kinesins exhibit a diverse range of design principles, which in turn increases their functional versatility in cells.
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Affiliation(s)
- Claire E Walczak
- Medical Sciences, Indiana University, Bloomington, Indiana 47405;
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Asenjo AB, Chatterjee C, Tan D, DePaoli V, Rice WJ, Diaz-Avalos R, Silvestry M, Sosa H. Structural model for tubulin recognition and deformation by kinesin-13 microtubule depolymerases. Cell Rep 2013; 3:759-68. [PMID: 23434508 DOI: 10.1016/j.celrep.2013.01.030] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2012] [Revised: 12/12/2012] [Accepted: 01/24/2013] [Indexed: 10/27/2022] Open
Abstract
To elucidate the structural basis of the mechanism of microtubule depolymerization by kinesin-13s, we analyzed complexes of tubulin and the Drosophila melanogaster kinesin-13 KLP10A by electron microscopy (EM) and fluorescence polarization microscopy. We report a nanometer-resolution (1.1 nm) cryo-EM three-dimensional structure of the KLP10A head domain (KLP10AHD) bound to curved tubulin. We found that binding of KLP10AHD induces a distinct tubulin configuration with displacement (shear) between tubulin subunits in addition to curvature. In this configuration, the kinesin-binding site differs from that in straight tubulin, providing an explanation for the distinct interaction modes of kinesin-13s with the microtubule lattice or its ends. The KLP10AHD-tubulin interface comprises three areas of interaction, suggesting a crossbow-type tubulin-bending mechanism. These areas include the kinesin-13 family conserved KVD residues, and as predicted from the crossbow model, mutating these residues changes the orientation and mobility of KLP10AHDs interacting with the microtubule.
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Affiliation(s)
- Ana B Asenjo
- Department of Physiology and Biophysics, Albert Einstein College of Medicine, Bronx, NY 10461, USA
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Mak M, Reinhart-King CA, Erickson D. Elucidating mechanical transition effects of invading cancer cells with a subnucleus-scaled microfluidic serial dimensional modulation device. LAB ON A CHIP 2013; 13:340-8. [PMID: 23212313 PMCID: PMC3750734 DOI: 10.1039/c2lc41117b] [Citation(s) in RCA: 77] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
Mechanical boundaries that define and regulate biological processes, such as cell-cell junctions and dense extracellular matrix networks, exist throughout the physiological landscape. During metastasis, cancer cells are able to invade across these barriers and spread to distant tissues. While transgressing boundaries is a necessary step for distal colonies to form, little is known about interface effects on cell behavior during invasion. Here we introduce a device and metric to assess cell transition effects across mechanical barriers. Using MDA-MB-231 cells, a highly metastatic breast adenocarcinoma cell line, our results demonstrate that dimensional modulation in confined spaces with mechanical barriers smaller than the cell nucleus can induce distinct invasion phases and elongated morphological states. Further investigations on the impact of microtubule stabilization and drug resistance reveal that taxol-treated cells have reduced ability in invading across tight spaces and lose their super-diffusive migratory state and taxol-resistant cells exhibit asymmetric cell division at barrier interfaces. These results illustrate that subnucleus-scaled confinement modulation can play a distinctive role in inducing behavioral responses in invading cells and can help reveal the mechanical elements of non-proteolytic invasion.
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Affiliation(s)
- Michael Mak
- Biomedical Engineering Department, Cornell University, Ithaca, NY, United States
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Interplay Between Spindle Architecture and Function. INTERNATIONAL REVIEW OF CELL AND MOLECULAR BIOLOGY 2013; 306:83-125. [DOI: 10.1016/b978-0-12-407694-5.00003-1] [Citation(s) in RCA: 63] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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Roubinet C, Tran PT, Piel M. Common mechanisms regulating cell cortex properties during cell division and cell migration. Cytoskeleton (Hoboken) 2012; 69:957-72. [PMID: 23125194 DOI: 10.1002/cm.21086] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2012] [Revised: 09/28/2012] [Accepted: 10/02/2012] [Indexed: 12/14/2022]
Abstract
Single cell morphogenesis results from a balance of forces involving internal pressure (also called turgor pressure in plants and fungi) and the plastic and dynamic outer shell of the cell. Dominated by the cell wall in plants and fungi, mechanical properties of the outer shell of animal cells arise from the cell cortex, which is mostly composed of the plasma membrane (and membrane proteins) and the underlying meshwork of actin filaments and myosin motors (and associated proteins). In this review, following Bray and White [1988; Science 239:883-889], we draw a parallel between the regulation of the cell cortex during cell division and cell migration in animal cells. Starting from the similarities in shape changes and underlying mechanical properties, we further propose that the analogy between cell division and cell migration might run deeper, down to the basic molecular mechanisms driving cell cortex remodeling. We focus our attention on how an heterogeneous and dynamic cortex can be generated to allow cell shape changes while preserving cell integrity.
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Affiliation(s)
- Chantal Roubinet
- Université de Toulouse, UPS, Centre de Biologie du Développement, Bâtiment 4R3, 118 route de Narbonne, F-31062 Toulouse, France.
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Gardner MK, Zanic M, Howard J. Microtubule catastrophe and rescue. Curr Opin Cell Biol 2012; 25:14-22. [PMID: 23092753 DOI: 10.1016/j.ceb.2012.09.006] [Citation(s) in RCA: 107] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2012] [Revised: 09/25/2012] [Accepted: 09/27/2012] [Indexed: 11/28/2022]
Abstract
Microtubules are long cylindrical polymers composed of tubulin subunits. In cells, microtubules play an essential role in architecture and motility. For example, microtubules give shape to cells, serve as intracellular transport tracks, and act as key elements in important cellular structures such as axonemes and mitotic spindles. To accomplish these varied functions, networks of microtubules in cells are very dynamic, continuously remodeling through stochastic length fluctuations at the ends of individual microtubules. The dynamic behavior at the end of an individual microtubule is termed 'dynamic instability'. This behavior manifests itself by periods of persistent microtubule growth interrupted by occasional switching to rapid shrinkage (called microtubule 'catastrophe'), and then by switching back from shrinkage to growth (called microtubule 'rescue'). In this review, we summarize recent findings which provide new insights into the mechanisms of microtubule catastrophe and rescue, and discuss the impact of these findings in regards to the role of microtubule dynamics inside of cells.
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Affiliation(s)
- Melissa K Gardner
- Department of Genetics, Cell Biology, and Development, University of Minnesota, Minneapolis, MN 55455, USA.
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