1
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Wang Y, Liu YR, Wang PY, Xie P. Computational Studies Reveal How Passive Cross-Linkers Regulate Anaphase Spindle Elongation. J Phys Chem B 2024; 128:1194-1204. [PMID: 38287918 DOI: 10.1021/acs.jpcb.3c07655] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2024]
Abstract
In eukaryotic cell division, a series of events are organized to produce two daughter cells. The spindle elongation in anaphase B is essential for providing enough space to maintain cell size and distribute sister chromatids properly, which is associated with microtubules and microtubule-associated proteins such as kinesin-5 Eg5 and the Ase1-related protein, PRC1. The available experimental data indicated that after the start of anaphase B more PRC1 proteins can bind to the antiparallel microtubule pairs in the spindle but the excess amount of PRC1 proteins can lead to the failure of cell division, indicating that PRC1 proteins can regulate the spindle elongation in a concentration-dependent manner. However, the underlying mechanism of the PRC1 proteins regulating the spindle elongation has not been explained up to now. Here, we use a simplified model, where only the two important participants (kinesin-5 Eg5 motors and PRC1 proteins) are considered, to study the spindle elongation during anaphase B. We first show that only in the appropriate range of the PRC1 concentration can the spindle elongation complete properly. Furthermore, we explore the underlying mechanism of PRC1 as a regulator for spindle elongation.
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Affiliation(s)
- Yao Wang
- Key Laboratory of Soft Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yu-Ru Liu
- Key Laboratory of Soft Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Peng-Ye Wang
- Key Laboratory of Soft Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Ping Xie
- Key Laboratory of Soft Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
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2
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LaFountain JR, Seaman CE, Cohan CS, Oldenbourg R. Sliding of antiparallel microtubules drives bipolarization of monoastral spindles. Cytoskeleton (Hoboken) 2024; 81:167-183. [PMID: 37812128 PMCID: PMC11172411 DOI: 10.1002/cm.21800] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2023] [Revised: 09/21/2023] [Accepted: 09/23/2023] [Indexed: 10/10/2023]
Abstract
Time-lapse imaging with liquid crystal polarized light (LC-PolScope) and fluorescent speckle microscopy (FSM) enabled this study of spindle microtubules in monoastral spindles that were produced in crane-fly spermatocytes through flattening-induced centrosome displacement. Monoastral spindles are found in several other contexts: after laser ablation of one of a cell's two centrosomes (in the work of Khodjakov et al.), in Drosophila "urchin" mutants (in the works of Heck et al. and of Wilson et al.), in Sciara males (in the works of Fuge and of Metz), and in RNAi variants of Drosophila S2 cells (in the work of Goshima et al.). In all cases, just one pole has a centrosome (the astral pole); the other lacks a centrosome (the anastral pole). Thus, the question: How is the anastral half-spindle, lacking a centrosome, constructed? We learned that monoastral spindles are assembled in two phases: Phase I assembles the astral half-spindle composed of centrosomal microtubules, and Phase II assembles microtubules of the anastral half through extension of new microtubule polymerization outward from the spindle's equatorial mid-zone. That process uses plus ends of existing centrosomal microtubules as guiding templates to assemble anastral microtubules of opposite polarity. Anastral microtubules slide outward with their minus ends leading, thereby establishing proper bipolarity just like in normal biastral spindles that have two centrosomes.
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Affiliation(s)
- James R LaFountain
- Department of Biological Sciences, University at Buffalo, Buffalo, New York, USA
| | - Catherine E Seaman
- Department of Biological Sciences, University at Buffalo, Buffalo, New York, USA
| | - Christopher S Cohan
- Department of Pathology and Anatomy, University at Buffalo, Buffalo, New York, USA
| | - Rudolf Oldenbourg
- Eugene Bell Center, Marine Biological Laboratory, Woods Hole, Massachusetts, USA
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3
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Zhang Y, Fan B, Li X, Tang Y, Shao J, Liu L, Ren Y, Yang Y, Xu B. Phosphorylation of adducin-1 by TPX2 promotes interpolar microtubule homeostasis and precise chromosome segregation in mouse oocytes. Cell Biosci 2022; 12:205. [PMID: 36539904 PMCID: PMC9769001 DOI: 10.1186/s13578-022-00943-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2022] [Accepted: 12/16/2022] [Indexed: 12/24/2022] Open
Abstract
BACKGROUND ADD1 (adducin-1) and TPX2 (targeting protein for Xklp2) are centrosomal proteins and regulate mitotic spindle assembly. Mammalian oocytes that segregate homologous chromosomes in Meiosis I and sister chromatids in Meiosis II with a spindle lacking centrosomes are more prone to chromosome segregation errors than in mitosis. However, the regulatory mechanisms of oocyte spindle assembly and the functions of ADD1 and TPX2 in this process remain elusive. RESULT We found that the expression levels and localization of ADD1, S726 phosphorylated ADD1 (p-ADD1), and TPX2 proteins exhibited spindle assembly-dependent dynamic changes during mouse oocyte meiosis. Taxol treatment, which stabilizes the microtubule polymer and protects it from disassembly, made the signals of ADD1, p-ADD1, and TPX2 present in the microtubule organizing centers of small asters and spindles. Knockdown of approximately 60% of ADD1 protein levels destabilized interpolar microtubules in the meiotic spindle, resulting in aberrant chromosome alignment, reduced first polar body extrusion, and increased aneuploidy in metaphase II oocytes, but did not affect K-fiber homeostasis and the expression and localization of TPX2. Strikingly, TPX2 deficiency caused increased protein content of ADD1, but decreased expression and detachment of p-ADD1 from the spindle, thereby arresting mouse oocytes at the metaphase I stage with collapsed spindles. CONCLUSION Phosphorylation of ADD1 at S726 by TPX2 mediates acentriolar spindle assembly and precise chromosome segregation in mouse oocytes.
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Affiliation(s)
- Ying Zhang
- grid.410727.70000 0001 0526 1937Institute of Special Animal and Plant Sciences, Chinese Academy of Agricultural Sciences, #4899 Juye Street, Jingyue District, Changchun, 130112 Jilin China ,grid.410727.70000 0001 0526 1937State Key Laboratory for Molecular Biology of Special Economic Animals, Institute of Special Animal and Plant Sciences, Chinese Academy of Agricultural Sciences, Changchun, Jilin China
| | - Bingfeng Fan
- grid.410727.70000 0001 0526 1937Institute of Special Animal and Plant Sciences, Chinese Academy of Agricultural Sciences, #4899 Juye Street, Jingyue District, Changchun, 130112 Jilin China ,grid.410727.70000 0001 0526 1937State Key Laboratory for Molecular Biology of Special Economic Animals, Institute of Special Animal and Plant Sciences, Chinese Academy of Agricultural Sciences, Changchun, Jilin China
| | - Xiaoxia Li
- grid.410727.70000 0001 0526 1937Institute of Special Animal and Plant Sciences, Chinese Academy of Agricultural Sciences, #4899 Juye Street, Jingyue District, Changchun, 130112 Jilin China ,grid.410727.70000 0001 0526 1937State Key Laboratory for Molecular Biology of Special Economic Animals, Institute of Special Animal and Plant Sciences, Chinese Academy of Agricultural Sciences, Changchun, Jilin China ,College of Animal Science and Technology, Jilin Agriculture Science and Technology University, Jilin, China
| | - Yu Tang
- grid.410727.70000 0001 0526 1937Institute of Special Animal and Plant Sciences, Chinese Academy of Agricultural Sciences, #4899 Juye Street, Jingyue District, Changchun, 130112 Jilin China ,grid.410727.70000 0001 0526 1937State Key Laboratory for Molecular Biology of Special Economic Animals, Institute of Special Animal and Plant Sciences, Chinese Academy of Agricultural Sciences, Changchun, Jilin China
| | - Jing Shao
- grid.410727.70000 0001 0526 1937Institute of Special Animal and Plant Sciences, Chinese Academy of Agricultural Sciences, #4899 Juye Street, Jingyue District, Changchun, 130112 Jilin China ,grid.410727.70000 0001 0526 1937State Key Laboratory for Molecular Biology of Special Economic Animals, Institute of Special Animal and Plant Sciences, Chinese Academy of Agricultural Sciences, Changchun, Jilin China
| | - Lixiang Liu
- grid.410727.70000 0001 0526 1937Institute of Special Animal and Plant Sciences, Chinese Academy of Agricultural Sciences, #4899 Juye Street, Jingyue District, Changchun, 130112 Jilin China ,grid.410727.70000 0001 0526 1937State Key Laboratory for Molecular Biology of Special Economic Animals, Institute of Special Animal and Plant Sciences, Chinese Academy of Agricultural Sciences, Changchun, Jilin China
| | - Yuhe Ren
- grid.410727.70000 0001 0526 1937Institute of Special Animal and Plant Sciences, Chinese Academy of Agricultural Sciences, #4899 Juye Street, Jingyue District, Changchun, 130112 Jilin China
| | - Yifeng Yang
- grid.410727.70000 0001 0526 1937Institute of Special Animal and Plant Sciences, Chinese Academy of Agricultural Sciences, #4899 Juye Street, Jingyue District, Changchun, 130112 Jilin China ,grid.410727.70000 0001 0526 1937State Key Laboratory for Molecular Biology of Special Economic Animals, Institute of Special Animal and Plant Sciences, Chinese Academy of Agricultural Sciences, Changchun, Jilin China
| | - Baozeng Xu
- grid.410727.70000 0001 0526 1937Institute of Special Animal and Plant Sciences, Chinese Academy of Agricultural Sciences, #4899 Juye Street, Jingyue District, Changchun, 130112 Jilin China ,grid.410727.70000 0001 0526 1937State Key Laboratory for Molecular Biology of Special Economic Animals, Institute of Special Animal and Plant Sciences, Chinese Academy of Agricultural Sciences, Changchun, Jilin China
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Hotta T, Lee YRJ, Higaki T, Hashimoto T, Liu B. Two Kinesin-14A Motors Oligomerize to Drive Poleward Microtubule Convergence for Acentrosomal Spindle Morphogenesis in Arabidopsis thaliana. Front Cell Dev Biol 2022; 10:949345. [PMID: 35982853 PMCID: PMC9380777 DOI: 10.3389/fcell.2022.949345] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2022] [Accepted: 06/16/2022] [Indexed: 11/13/2022] Open
Abstract
Plant cells form acentrosomal spindles with microtubules (MTs) converged toward two structurally undefined poles by employing MT minus end-directed Kinesin-14 motors. To date, it is unclear whether the convergent bipolar MT array assumes unified poles in plant spindles, and if so, how such a goal is achieved. Among six classes of Kinesin-14 motors in Arabidopsis thaliana, the Kinesin-14A motors ATK1 (KatA) and ATK5 share the essential function in spindle morphogenesis. To understand how the two functionally redundant Kinesin-14A motors contributed to the spindle assembly, we had ATK1-GFP and ATK5-GFP fusion proteins expressed in their corresponding null mutants and found that they were functionally comparable to their native forms. Although ATK1 was a nuclear protein and ATK5 cytoplasmic prior to nuclear envelop breakdown, at later mitotic stages, the two motors shared similar localization patterns of uniform association with both spindle and phragmoplast MTs. We found that ATK1 and ATK5 were rapidly concentrated toward unified polar foci when cells were under hyperosmotic conditions. Concomitantly, spindle poles became perfectly focused as if there were centrosome-like MT-organizing centers where ATK1 and ATK5 were highly enriched and at which kinetochore fibers pointed. The separation of ATK1/ATK5-highlighted MTs from those of kinetochore fibers suggested that the motors translocated interpolar MTs. Our protein purification and live-cell imaging results showed that ATK1 and ATK5 are associated with each other in vivo. The stress-induced spindle pole convergence was also accompanied by poleward accumulation of the MT nucleator γ-tubulin. These results led to the conclusion that the two Kinesin-14A motors formed oligomeric motor complexes that drove MT translocation toward the spindle pole to establish acentrosomal spindles with convergent poles.
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Affiliation(s)
- Takashi Hotta
- Department of Plant Biology, College of Biological Sciences, University of California, Davis, Davis, CA, United States
- Department of Cell and Developmental Biology, University of Michigan Medical School, Ann Arbor, MI, United States
- Division of Biological Science, Nara Institute of Science and Technology, Ikoma, Japan
| | - Yuh-Ru Julie Lee
- Department of Plant Biology, College of Biological Sciences, University of California, Davis, Davis, CA, United States
| | - Takumi Higaki
- Faculty of Advanced Science and Technology, Kumamoto University, Kumamoto, Japan
- International Research Organization for Advanced Science and Technology, Kumamoto University, Kumamoto, Japan
| | - Takashi Hashimoto
- Division of Biological Science, Nara Institute of Science and Technology, Ikoma, Japan
| | - Bo Liu
- Department of Plant Biology, College of Biological Sciences, University of California, Davis, Davis, CA, United States
- *Correspondence: Bo Liu,
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Batman U, Deretic J, Firat-Karalar EN. The ciliopathy protein CCDC66 controls mitotic progression and cytokinesis by promoting microtubule nucleation and organization. PLoS Biol 2022; 20:e3001708. [PMID: 35849559 PMCID: PMC9333452 DOI: 10.1371/journal.pbio.3001708] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2021] [Revised: 07/28/2022] [Accepted: 06/14/2022] [Indexed: 11/23/2022] Open
Abstract
Precise spatiotemporal control of microtubule nucleation and organization is critical for faithful segregation of cytoplasmic and genetic material during cell division and signaling via the primary cilium in quiescent cells. Microtubule-associated proteins (MAPs) govern assembly, maintenance, and remodeling of diverse microtubule arrays. While a set of conserved MAPs are only active during cell division, an emerging group of MAPs acts as dual regulators in dividing and nondividing cells. Here, we elucidated the nonciliary functions and molecular mechanism of action of the ciliopathy-linked protein CCDC66, which we previously characterized as a regulator of ciliogenesis in quiescent cells. We showed that CCDC66 dynamically localizes to the centrosomes, the bipolar spindle, the spindle midzone, the central spindle, and the midbody in dividing cells and interacts with the core machinery of centrosome maturation and MAPs involved in cell division. Loss-of-function experiments revealed its functions during mitotic progression and cytokinesis. Specifically, CCDC66 depletion resulted in defective spindle assembly and orientation, kinetochore fiber stability, chromosome alignment in metaphase as well as central spindle and midbody assembly and organization in anaphase and cytokinesis. Notably, CCDC66 regulates mitotic microtubule nucleation via noncentrosomal and centrosomal pathways via recruitment of gamma-tubulin to the centrosomes and the spindle. Additionally, CCDC66 bundles microtubules in vitro and in cells by its C-terminal microtubule-binding domain. Phenotypic rescue experiments showed that the microtubule and centrosome-associated pools of CCDC66 individually or cooperatively mediate its mitotic and cytokinetic functions. Collectively, our findings identify CCDC66 as a multifaceted regulator of the nucleation and organization of the diverse mitotic and cytokinetic microtubule arrays and provide new insight into nonciliary defects that underlie ciliopathies. The ciliopathy-linked protein CCDC66 is only known for its ciliary functions. This study reveals that CCDC66 also has extensive non-ciliary functions, localizing to the spindle poles, spindle midzone, central spindle and midbody throughout cell division, where it regulates mitosis and cytokinesis by promoting microtubule nucleation and organization.
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Affiliation(s)
- Umut Batman
- Department of Molecular Biology and Genetics, Koç University, Istanbul, Turkey
| | - Jovana Deretic
- Department of Molecular Biology and Genetics, Koç University, Istanbul, Turkey
| | - Elif Nur Firat-Karalar
- Department of Molecular Biology and Genetics, Koç University, Istanbul, Turkey
- Koç University School of Medicine, Istanbul, Turkey
- * E-mail:
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6
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Kouznetsova A, Liu JG, Valentiniene S, Brismar H, Höög C. Age-dependent aneuploidy in mammalian oocytes instigated at the second meiotic division. Aging Cell 2022; 21:e13649. [PMID: 35665589 PMCID: PMC9282850 DOI: 10.1111/acel.13649] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2021] [Revised: 02/07/2022] [Accepted: 05/18/2022] [Indexed: 11/08/2022] Open
Abstract
Ageing severely affects the chromosome segregation process in human oocytes resulting in aneuploidy, infertility and developmental disorders. A considerable amount of segregation errors in humans are introduced at the second meiotic division. We have here compared the chromosome segregation process in young adult and aged female mice during the second meiotic division. More than half of the oocytes in aged mice displayed chromosome segregation irregularities at anaphase II, resulting in dramatically increased level of aneuploidy in haploid gametes, from 4% in young adult mice to 30% in aged mice. We find that the post‐metaphase II process that efficiently corrects aberrant kinetochore‐microtubule attachments in oocytes in young adult mice is approximately 10‐fold less efficient in aged mice, in particular affecting chromosomes that show small inter‐centromere distances at the metaphase II stage in aged mice. Our results reveal that post‐metaphase II processes have critical impact on age‐dependent aneuploidy in mammalian eggs.
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Affiliation(s)
- Anna Kouznetsova
- Department of Cell and Molecular Biology Karolinska Institutet Stockholm Sweden
| | - Jian Guo Liu
- Department of Cell and Molecular Biology Karolinska Institutet Stockholm Sweden
| | - Sonata Valentiniene
- Department of Cell and Molecular Biology Karolinska Institutet Stockholm Sweden
| | - Hjalmar Brismar
- Science for Life Laboratory, Department of Applied Physics Royal Institute of Technology Solna Sweden
| | - Christer Höög
- Department of Cell and Molecular Biology Karolinska Institutet Stockholm Sweden
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7
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The chirality of the mitotic spindle provides a mechanical response to forces and depends on microtubule motors and augmin. Curr Biol 2022; 32:2480-2493.e6. [PMID: 35537456 PMCID: PMC9235856 DOI: 10.1016/j.cub.2022.04.035] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2021] [Revised: 02/17/2022] [Accepted: 04/13/2022] [Indexed: 12/24/2022]
Abstract
Forces produced by motor proteins and microtubule dynamics within the mitotic spindle are crucial for proper chromosome segregation. In addition to linear forces, rotational forces or torques are present in the spindle, which are reflected in the left-handed twisted shapes of microtubule bundles that make the spindle chiral. However, the biological role and molecular origins of spindle chirality are unknown. By developing methods for measuring the spindle twist, we show that spindles are most chiral near the metaphase-to-anaphase transition. To assess the role of chirality in spindle mechanics, we compressed the spindles along their axis. This resulted in a stronger left-handed twist, suggesting that the twisted shape allows for a mechanical response to forces. Inhibition or depletion of motor proteins that perform chiral stepping, Eg5/kinesin-5, Kif18A/kinesin-8, MKLP1/kinesin-6, and dynein, decreased the left-handed twist or led to right-handed twist, implying that these motors regulate the twist by rotating microtubules within their antiparallel overlaps or at the spindle pole. A right-handed twist was also observed after the depletion of the microtubule nucleator augmin, indicating its contribution to the twist through the nucleation of antiparallel bridging microtubules. The uncovered switch from left-handed to right-handed twist reveals the existence of competing mechanisms that promote twisting in opposite directions. As round spindles are more twisted than the elongated ones are, we infer that bending and twisting moments are generated by similar molecular mechanisms and propose a physiological role for spindle chirality in allowing the spindle to absorb mechanical load. Video abstract
Spindle twist depends on torque-generating motors Eg5, Kif18A, MKLP1, and dynein Without the microtubule nucleator augmin, spindles show right-handed twist Compression of the spindle along the axis increases the left-handed twist Rounder spindles are more twisted than elongated ones are
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8
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Wei YL, Fan XJ, Diao YY, She ZY, Wang XR. Kinesin-14 KIFC1 modulates spindle assembly and chromosome segregation in mouse spermatocytes. Exp Cell Res 2022; 414:113095. [DOI: 10.1016/j.yexcr.2022.113095] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2021] [Revised: 03/02/2022] [Accepted: 03/03/2022] [Indexed: 11/04/2022]
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9
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Pomp O, Lim HYG, Skory RM, Moverley AA, Tetlak P, Bissiere S, Plachta N. A monoastral mitotic spindle determines lineage fate and position in the mouse embryo. Nat Cell Biol 2022; 24:155-167. [PMID: 35102267 DOI: 10.1038/s41556-021-00826-3] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2021] [Accepted: 11/30/2021] [Indexed: 12/11/2022]
Abstract
During mammalian development, the first asymmetric cell divisions segregate cells into inner and outer positions of the embryo to establish the pluripotent and trophectoderm lineages. Typically, polarity components differentially regulate the mitotic spindle via astral microtubule arrays to trigger asymmetric division patterns. However, early mouse embryos lack centrosomes, the microtubule-organizing centres (MTOCs) that usually generate microtubule asters. Thus, it remains unknown whether spindle organization regulates lineage segregation. Here we find that heterogeneities in cell polarity in the early 8-cell-stage mouse embryo trigger the assembly of a highly asymmetric spindle organization. This spindle arises in an unusual modular manner, forming a single microtubule aster from an apically localized, non-centrosomal MTOC, before joining it to the rest of the spindle apparatus. When fully assembled, this 'monoastral' spindle triggers spatially asymmetric division patterns to segregate cells into inner and outer positions. Moreover, the asymmetric inheritance of spindle components causes differential cell polarization to determine pluripotent versus trophectoderm lineage fate.
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Affiliation(s)
- Oz Pomp
- Department of Cell and Developmental Biology, Institute for Regenerative Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Hui Yi Grace Lim
- Institute of Molecular and Cell Biology, ASTAR, Singapore, Singapore
| | - Robin M Skory
- Department of Cell and Developmental Biology, Institute for Regenerative Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Adam A Moverley
- Department of Cell and Developmental Biology, Institute for Regenerative Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Piotr Tetlak
- Department of Cell and Developmental Biology, Institute for Regenerative Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Stephanie Bissiere
- Department of Cell and Developmental Biology, Institute for Regenerative Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Nicolas Plachta
- Department of Cell and Developmental Biology, Institute for Regenerative Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA.
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10
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Nabi D, Drechsler H, Pschirer J, Korn F, Schuler N, Diez S, Jessberger R, Chacón M. CENP-V is required for proper chromosome segregation through interaction with spindle microtubules in mouse oocytes. Nat Commun 2021; 12:6547. [PMID: 34764261 PMCID: PMC8586017 DOI: 10.1038/s41467-021-26826-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2020] [Accepted: 10/21/2021] [Indexed: 11/08/2022] Open
Abstract
Proper chromosome segregation is essential to avoid aneuploidy, yet this process fails with increasing age in mammalian oocytes. Here we report a role for the scarcely described protein CENP-V in oocyte spindle formation and chromosome segregation. We show that depending on the oocyte maturation state, CENP-V localizes to centromeres, to microtubule organizing centers, and to spindle microtubules. We find that Cenp-V-/- oocytes feature severe deficiencies, including metaphase I arrest, strongly reduced polar body extrusion, increased numbers of mis-aligned chromosomes and aneuploidy, multipolar spindles, unfocused spindle poles and loss of kinetochore spindle fibres. We also show that CENP-V protein binds, diffuses along, and bundles microtubules in vitro. The spindle assembly checkpoint arrests about half of metaphase I Cenp-V-/- oocytes from young adults only. This finding suggests checkpoint weakening in ageing oocytes, which mature despite carrying mis-aligned chromosomes. Thus, CENP-V is a microtubule bundling protein crucial to faithful oocyte meiosis, and Cenp-V-/- oocytes reveal age-dependent weakening of the spindle assembly checkpoint.
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Affiliation(s)
- Dalileh Nabi
- Institute of Physiological Chemistry, Medical Faculty Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany
- Department of Neuropediatrics Charité-Universitätsmedizin Berlin, Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Berlin, Germany
| | - Hauke Drechsler
- B CUBE-Center for Molecular Bioengineering, Technische Universität Dresden, Dresden, Germany
| | - Johannes Pschirer
- Institute of Physiological Chemistry, Medical Faculty Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany
| | - Franz Korn
- Institute of Physiological Chemistry, Medical Faculty Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany
| | - Nadine Schuler
- Institute of Physiological Chemistry, Medical Faculty Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany
| | - Stefan Diez
- B CUBE-Center for Molecular Bioengineering, Technische Universität Dresden, Dresden, Germany
- Cluster of Excellence Physics of Life, Technische Universität Dresden, Dresden, Germany
- Max Planck Institute of Molecular Cell Biology and Genetics, Dresden, Germany
| | - Rolf Jessberger
- Institute of Physiological Chemistry, Medical Faculty Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany.
| | - Mariola Chacón
- Institute of Physiological Chemistry, Medical Faculty Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany.
- CABIMER, Centro Andaluz de Biología Molecular & Medicina Regenerativa, Sevilla, Spain.
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11
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Vukušić K, Tolić IM. Anaphase B: Long-standing models meet new concepts. Semin Cell Dev Biol 2021; 117:127-139. [PMID: 33849764 PMCID: PMC8406420 DOI: 10.1016/j.semcdb.2021.03.023] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2021] [Revised: 03/26/2021] [Accepted: 03/28/2021] [Indexed: 12/16/2022]
Abstract
Mitotic cell divisions ensure stable transmission of genetic information from a mother to daughter cells in a series of generations. To ensure this crucial task is accomplished, the cell forms a bipolar structure called the mitotic spindle that divides sister chromatids to the opposite sides of the dividing mother cell. After successful establishment of stable attachments of microtubules to chromosomes and inspection of connections between them, at the heart of mitosis, the cell starts the process of segregation. This spectacular moment in the life of a cell is termed anaphase, and it involves two distinct processes: depolymerization of microtubules bound to chromosomes, which is also known as anaphase A, and elongation of the spindle or anaphase B. Both processes ensure physical separation of disjointed sister chromatids. In this chapter, we review the mechanisms of anaphase B spindle elongation primarily in mammalian systems, combining different pioneering ideas and concepts with more recent findings that shed new light on the force generation and regulation of biochemical modules operating during spindle elongation. Finally, we present a comprehensive model of spindle elongation that includes structural, biophysical, and molecular aspects of anaphase B.
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Affiliation(s)
- Kruno Vukušić
- Division of Molecular Biology, Ruđer Bošković Institute, Bijenička cesta 54, 10000 Zagreb, Croatia.
| | - Iva M Tolić
- Division of Molecular Biology, Ruđer Bošković Institute, Bijenička cesta 54, 10000 Zagreb, Croatia.
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12
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Chemical tools for dissecting cell division. Nat Chem Biol 2021; 17:632-640. [PMID: 34035515 PMCID: PMC10157795 DOI: 10.1038/s41589-021-00798-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2020] [Accepted: 04/13/2021] [Indexed: 02/03/2023]
Abstract
Components of the cell division machinery typically function at varying cell cycle stages and intracellular locations. To dissect cellular mechanisms during the rapid division process, small-molecule probes act as complementary approaches to genetic manipulations, with advantages of temporal and in some cases spatial control and applicability to multiple model systems. This Review focuses on recent advances in chemical probes and applications to address select questions in cell division. We discuss uses of both enzyme inhibitors and chemical inducers of dimerization, as well as emerging techniques to promote future investigations. Overall, these concepts may open new research directions for applying chemical probes to advance cell biology.
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13
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Risteski P, Jagrić M, Pavin N, Tolić IM. Biomechanics of chromosome alignment at the spindle midplane. Curr Biol 2021; 31:R574-R585. [PMID: 34033791 DOI: 10.1016/j.cub.2021.03.082] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
During metaphase, chromosomes are aligned in a lineup at the equatorial plane of the spindle to ensure synchronous poleward movement of chromatids in anaphase and proper nuclear reformation at the end of mitosis. Chromosome alignment relies on microtubules, several types of motor protein and numerous other microtubule-associated and regulatory proteins. Because of the multitude of players involved, the mechanisms of chromosome alignment are still under debate. Here, we discuss the current models of alignment based on poleward pulling forces exerted onto sister kinetochores by kinetochore microtubules, which show length-dependent dynamics and undergo poleward flux, and polar ejection forces that push the chromosome arms away from the pole. We link these models with the recent ideas based on mechanical coupling between bridging and kinetochore microtubules, where sliding of bridging microtubules promotes overlap length-dependent sliding of kinetochore fibers and thus the alignment of sister kinetochores at the spindle equator. Finally, we discuss theoretical models of forces acting on chromosomes during metaphase.
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Affiliation(s)
- Patrik Risteski
- Division of Molecular Biology, Ruđer Bošković Institute, Bijenička cesta 54, 10000 Zagreb, Croatia
| | - Mihaela Jagrić
- Division of Molecular Biology, Ruđer Bošković Institute, Bijenička cesta 54, 10000 Zagreb, Croatia
| | - Nenad Pavin
- Department of Physics, Faculty of Science, University of Zagreb, Bijenička cesta 32, 10000 Zagreb, Croatia
| | - Iva M Tolić
- Division of Molecular Biology, Ruđer Bošković Institute, Bijenička cesta 54, 10000 Zagreb, Croatia.
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14
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McIntosh JR. Anaphase A. Semin Cell Dev Biol 2021; 117:118-126. [PMID: 33781672 DOI: 10.1016/j.semcdb.2021.03.009] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2021] [Revised: 03/16/2021] [Accepted: 03/16/2021] [Indexed: 10/21/2022]
Abstract
Anaphase A is the motion of recently separated chromosomes to the spindle pole they face. It is accompanied by the shortening of kinetochore-attached microtubules. The requisite tubulin depolymerization may occur at kinetochores, at poles, or both, depending on the species and/or the time in mitosis. These depolymerization events are local and suggest that cells regulate microtubule dynamics in specific places, presumably by the localization of relevant enzymes and microtubule-associated proteins to specific loci, such as pericentriolar material and outer kinetochores. Motor enzymes can contribute to anaphase A, both by altering microtubule stability and by pushing or pulling microtubules through the cell. The generation of force on chromosomes requires couplings that can both withstand the considerable force that spindles can generate and simultaneously permit tubulin addition and loss. This chapter reviews literature on the molecules that regulate anaphase microtubule dynamics, couple dynamic microtubules to kinetochores and poles, and generate forces for microtubule and chromosome motion.
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Affiliation(s)
- J Richard McIntosh
- Dept. of Molecular, Cellular, and Developmental Biology University of Colorado, Boulder, CO 80309-0347, USA.
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15
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Tolic´ IM, Pavin N. Mitotic spindle: lessons from theoretical modeling. Mol Biol Cell 2021; 32:218-222. [PMID: 33507108 PMCID: PMC8098832 DOI: 10.1091/mbc.e20-05-0335] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2020] [Revised: 11/23/2020] [Accepted: 11/24/2020] [Indexed: 11/16/2022] Open
Abstract
Cell biology is immensely complex. To understand how cells work, we try to find patterns and suggest hypotheses to identify underlying mechanisms. However, it is not always easy to create a coherent picture from a huge amount of experimental data on biological systems, where the main players have multiple interactions or act in redundant pathways. In such situations, when a hypothesis does not lead to a conclusion in a direct way, theoretical modeling is a powerful tool because it allows us to formulate hypotheses in a quantitative manner and understand their consequences. A successful model should not only reproduce the basic features of the system but also provide exciting predictions, motivating new experiments. Much is learned when a model based on generally accepted knowledge cannot explain experiments of interest, as this indicates that the original hypothesis needs to be revised. In this Perspective, we discuss these points using our experiences in combining experiments with theory in the field of mitotic spindle mechanics.
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Affiliation(s)
- Iva M. Tolic´
- Division of Molecular Biology, Rud¯er Boškovic´ Institute, 10000 Zagreb, Croatia
| | - Nenad Pavin
- Department of Physics, Faculty of Science, University of Zagreb, 10000 Zagreb, Croatia
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16
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Jagrić M, Risteski P, Martinčić J, Milas A, Tolić IM. Optogenetic control of PRC1 reveals its role in chromosome alignment on the spindle by overlap length-dependent forces. eLife 2021; 10:61170. [PMID: 33480356 PMCID: PMC7924949 DOI: 10.7554/elife.61170] [Citation(s) in RCA: 31] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2020] [Accepted: 01/21/2021] [Indexed: 12/27/2022] Open
Abstract
During metaphase, chromosome position at the spindle equator is regulated by the forces exerted by kinetochore microtubules and polar ejection forces. However, the role of forces arising from mechanical coupling of sister kinetochore fibers with bridging fibers in chromosome alignment is unknown. Here, we develop an optogenetic approach for acute removal of PRC1 to partially disassemble bridging fibers and show that they promote chromosome alignment. Tracking of the plus-end protein EB3 revealed longer antiparallel overlaps of bridging microtubules upon PRC1 removal, which was accompanied by misaligned and lagging kinetochores. Kif4A/kinesin-4 and Kif18A/kinesin-8 were found within the bridging fiber and largely lost upon PRC1 removal, suggesting that these proteins regulate the overlap length of bridging microtubules. We propose that PRC1-mediated crosslinking of bridging microtubules and recruitment of kinesins to the bridging fiber promote chromosome alignment by overlap length-dependent forces transmitted to the associated kinetochore fibers. Before cells divide to create copies of themselves, they need to duplicate their genetic material. To help split their DNA evenly, they build a machine called the mitotic spindle. The mitotic spindle is made of fine, tube-like structures called microtubules, which catch the chromosomes containing the genetic information and line them up at the center of the spindle. Microtubules push and pull the chromosomes by elongating or shortening their tips. But it remains unclear how the microtubules know when the chromosomes have reached center point. One way to find out is to remove proteins that accumulate in the middle of the spindle during division, such as the protein PRC1, which helps to assemble a subset of microtubules called bridging fibers, and the proteins Kif4A and Kif18A, which work like molecular rulers, shortening long microtubules. Usually, scientists would delete one of these proteins to see what impact this has. However, these experiments take days, giving the cell enough time to adapt and thus making it difficult to study the role of each of the proteins. Here, Jagrić, Risteski, Martinčić et al. used light to manipulate proteins at the exact moment of chromosome alignment and to move PRC1 from the spindle to the cell membrane. Consequently, Kif4A and Kif18A were removed from the spindle center. This caused the bridging fibers, which overlap with the microtubules that connect to the chromosomes, to become thinner. Jagrić et al. discovered that without the molecular ruler proteins, the bridging fibers were also too long. This increased the overlap between the microtubules in the center of the spindle, causing the chromosomes to migrate away from the center. This suggests that the alignment of chromosomes in the middle of the spindle depends on the bridging microtubules, which need to be of a certain length to effectively move and keep the chromosomes at the center. Thus, forces that move the chromosomes are generated both at the tips of the microtubules and along the wall of microtubules. These results might inspire other researchers to reassess the role of bridging fibers in cell division. The optogenetic technique described here could also help to determine the parts other proteins have to play. Ultimately, this might allow researchers to identify all the proteins needed to align the chromosomes.
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Affiliation(s)
- Mihaela Jagrić
- Division of Molecular Biology, Ruđer Bošković Institute, Zagreb, Croatia
| | - Patrik Risteski
- Division of Molecular Biology, Ruđer Bošković Institute, Zagreb, Croatia
| | - Jelena Martinčić
- Division of Molecular Biology, Ruđer Bošković Institute, Zagreb, Croatia
| | - Ana Milas
- Division of Molecular Biology, Ruđer Bošković Institute, Zagreb, Croatia
| | - Iva M Tolić
- Division of Molecular Biology, Ruđer Bošković Institute, Zagreb, Croatia
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17
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Juanes MA. Cytoskeletal Control and Wnt Signaling-APC's Dual Contributions in Stem Cell Division and Colorectal Cancer. Cancers (Basel) 2020; 12:E3811. [PMID: 33348689 PMCID: PMC7766042 DOI: 10.3390/cancers12123811] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2020] [Revised: 12/12/2020] [Accepted: 12/15/2020] [Indexed: 12/12/2022] Open
Abstract
Intestinal epithelium architecture is sustained by stem cell division. In principle, stem cells can divide symmetrically to generate two identical copies of themselves or asymmetrically to sustain tissue renewal in a balanced manner. The choice between the two helps preserve stem cell and progeny pools and is crucial for tissue homeostasis. Control of spindle orientation is a prime contributor to the specification of symmetric versus asymmetric cell division. Competition for space within the niche may be another factor limiting the stem cell pool. An integrative view of the multiple links between intracellular and extracellular signals and molecular determinants at play remains a challenge. One outstanding question is the precise molecular roles of the tumour suppressor Adenomatous polyposis coli (APC) for sustaining gut homeostasis through its respective functions as a cytoskeletal hub and a down regulator in Wnt signalling. Here, we review our current understanding of APC inherent activities and partners in order to explore novel avenues by which APC may act as a gatekeeper in colorectal cancer and as a therapeutic target.
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Affiliation(s)
- M. Angeles Juanes
- School of Health and Life Science, Teesside University, Middlesbrough TS1 3BX, UK;
- National Horizons Centre, Teesside University, 38 John Dixon Lane, Darlington DL1 1HG, UK
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18
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Pavin N, Tolić IM. Mechanobiology of the Mitotic Spindle. Dev Cell 2020; 56:192-201. [PMID: 33238148 DOI: 10.1016/j.devcel.2020.11.003] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2020] [Revised: 10/06/2020] [Accepted: 11/02/2020] [Indexed: 10/22/2022]
Abstract
The mitotic spindle is a microtubule-based assembly that separates the chromosomes during cell division. As the spindle is basically a mechanical micro machine, the understanding of its functioning is constantly motivating the development of experimental approaches based on mechanical perturbations, which are complementary to and work together with the classical genetics and biochemistry methods. Recent data emerging from these approaches in combination with theoretical modeling led to novel ideas and significant revisions of the basic concepts in the field. In this Perspective, we discuss the advances in the understanding of spindle mechanics, focusing on microtubule forces that control chromosome movements.
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Affiliation(s)
- Nenad Pavin
- Department of Physics, Faculty of Science, University of Zagreb, Bijenička cesta 32, 10000 Zagreb, Croatia.
| | - Iva M Tolić
- Division of Molecular Biology, Ruđer Bošković Institute, Bijenička cesta 54, 10000 Zagreb, Croatia.
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19
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Microtubule Organization in Striated Muscle Cells. Cells 2020; 9:cells9061395. [PMID: 32503326 PMCID: PMC7349303 DOI: 10.3390/cells9061395] [Citation(s) in RCA: 36] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2020] [Revised: 05/25/2020] [Accepted: 05/28/2020] [Indexed: 12/13/2022] Open
Abstract
Distinctly organized microtubule networks contribute to the function of differentiated cell types such as neurons, epithelial cells, skeletal myotubes, and cardiomyocytes. In striated (i.e., skeletal and cardiac) muscle cells, the nuclear envelope acts as the dominant microtubule-organizing center (MTOC) and the function of the centrosome—the canonical MTOC of mammalian cells—is attenuated, a common feature of differentiated cell types. We summarize the mechanisms known to underlie MTOC formation at the nuclear envelope, discuss the significance of the nuclear envelope MTOC for muscle function and cell cycle progression, and outline potential mechanisms of centrosome attenuation.
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20
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Fan T, Qu R, Yu Q, Sun B, Jiang X, Yang Y, Huang X, Zhou Z, Ouyang J, Zhong S, Dai J. Bioinformatics analysis of the biological changes involved in the osteogenic differentiation of human mesenchymal stem cells. J Cell Mol Med 2020; 24:7968-7978. [PMID: 32463168 PMCID: PMC7348183 DOI: 10.1111/jcmm.15429] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2020] [Revised: 04/30/2020] [Accepted: 05/07/2020] [Indexed: 12/17/2022] Open
Abstract
The mechanisms underlying the osteogenic differentiation of human bone marrow mesenchymal stem cells (hBMSCs) remain unclear. In the present study, we aimed to identify the key biological processes during osteogenic differentiation. To this end, we downloaded three microarray data sets from the Gene Expression Omnibus (GEO) database: GSE12266, GSE18043 and GSE37558. Differentially expressed genes (DEGs) were screened using the limma package, and enrichment analysis was performed. Protein-protein interaction network (PPI) analysis and visualization analysis were performed with STRING and Cytoscape. A total of 240 DEGs were identified, including 147 up-regulated genes and 93 down-regulated genes. Functional enrichment and pathways of the present DEGs include extracellular matrix organization, ossification, cell division, spindle and microtubule. Functional enrichment analysis of 10 hub genes showed that these genes are mainly enriched in microtubule-related biological changes, that is sister chromatid segregation, microtubule cytoskeleton organization involved in mitosis, and spindle microtubule. Moreover, immunofluorescence and Western blotting revealed dramatic quantitative and morphological changes in the microtubules during the osteogenic differentiation of human adipose-derived stem cells. In summary, the present results provide novel insights into the microtubule- and cytoskeleton-related biological process changes, identifying candidates for the further study of osteogenic differentiation of the mesenchymal stem cells.
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Affiliation(s)
- Tingyu Fan
- Guangdong Provincial Key Laboratory of Medical Biomechanics and Department of Anatomy, School of Basic Medical Science, Southern Medical University, Guangzhou, China
| | - Rongmei Qu
- Guangdong Provincial Key Laboratory of Medical Biomechanics and Department of Anatomy, School of Basic Medical Science, Southern Medical University, Guangzhou, China
| | - Qinghe Yu
- Zhujiang Hospital, Southern Medical University, Guangzhou, China
| | - Bing Sun
- Guangdong Provincial Key Laboratory of Medical Biomechanics and Department of Anatomy, School of Basic Medical Science, Southern Medical University, Guangzhou, China
| | - Xin Jiang
- Guangdong Provincial Key Laboratory of Medical Biomechanics and Department of Anatomy, School of Basic Medical Science, Southern Medical University, Guangzhou, China
| | - Yuchao Yang
- Guangdong Provincial Key Laboratory of Medical Biomechanics and Department of Anatomy, School of Basic Medical Science, Southern Medical University, Guangzhou, China
| | - Xiaolan Huang
- Guangdong Provincial Key Laboratory of Medical Biomechanics and Department of Anatomy, School of Basic Medical Science, Southern Medical University, Guangzhou, China
| | - Zhitao Zhou
- Central Laboratory, Southern Medical University, Guangzhou, China
| | - Jun Ouyang
- Guangdong Provincial Key Laboratory of Medical Biomechanics and Department of Anatomy, School of Basic Medical Science, Southern Medical University, Guangzhou, China
| | - Shizhen Zhong
- Guangdong Provincial Key Laboratory of Medical Biomechanics and Department of Anatomy, School of Basic Medical Science, Southern Medical University, Guangzhou, China
| | - Jingxing Dai
- Guangdong Provincial Key Laboratory of Medical Biomechanics and Department of Anatomy, School of Basic Medical Science, Southern Medical University, Guangzhou, China
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21
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Lin Y, Wei YL, She ZY. Kinesin-8 motors: regulation of microtubule dynamics and chromosome movements. Chromosoma 2020; 129:99-110. [PMID: 32417983 DOI: 10.1007/s00412-020-00736-7] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2019] [Revised: 05/06/2020] [Accepted: 05/07/2020] [Indexed: 02/01/2023]
Abstract
Microtubules are essential for intracellular transport, cell motility, spindle assembly, and chromosome segregation during cell division. Microtubule dynamics regulate the proper spindle organization and thus contribute to chromosome congression and segregation. Accumulating studies suggest that kinesin-8 motors are emerging regulators of microtubule dynamics and organizations. In this review, we provide an overview of the studies focused on kinesin-8 motors in cell division. We discuss the structures and molecular kinetics of kinesin-8 motors. We highlight the essential roles and mechanisms of kinesin-8 in the regulation of microtubule dynamics and spindle organization. We also shed light on the functions of kinesin-8 motors in chromosome movement and the spindle assembly checkpoint during the cell cycle.
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Affiliation(s)
- Yang Lin
- Department of Cell Biology and Genetics, The School of Basic Medical Sciences, Fujian Medical University, Fuzhou, 350122, Fujian, China.,Key Laboratory of Stem Cell Engineering and Regenerative Medicine, Fujian Province University, Fuzhou, 350122, Fujian, China
| | - Ya-Lan Wei
- Fujian Obstetrics and Gynecology Hospital, Fuzhou, 350011, Fujian, China.,Medical Research Center, Fujian Maternity and Child Health Hospital, Affiliated Hospital of Fujian Medical University, Fuzhou, 350001, Fujian, China
| | - Zhen-Yu She
- Department of Cell Biology and Genetics, The School of Basic Medical Sciences, Fujian Medical University, Fuzhou, 350122, Fujian, China. .,Key Laboratory of Stem Cell Engineering and Regenerative Medicine, Fujian Province University, Fuzhou, 350122, Fujian, China.
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22
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Suresh P, Long AF, Dumont S. Microneedle manipulation of the mammalian spindle reveals specialized, short-lived reinforcement near chromosomes. eLife 2020; 9:e53807. [PMID: 32191206 PMCID: PMC7117910 DOI: 10.7554/elife.53807] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2019] [Accepted: 03/18/2020] [Indexed: 12/21/2022] Open
Abstract
The spindle generates force to segregate chromosomes at cell division. In mammalian cells, kinetochore-fibers connect chromosomes to the spindle. The dynamic spindle anchors kinetochore-fibers in space and time to move chromosomes. Yet, how it does so remains poorly understood as we lack tools to directly challenge this anchorage. Here, we adapt microneedle manipulation to exert local forces on the spindle with spatiotemporal control. Pulling on kinetochore-fibers reveals the preservation of local architecture in the spindle-center over seconds. Sister, but not neighbor, kinetochore-fibers remain tightly coupled, restricting chromosome stretching. Further, pulled kinetochore-fibers pivot around poles but not chromosomes, retaining their orientation within 3 μm of chromosomes. This local reinforcement has a 20 s lifetime, and requires the microtubule crosslinker PRC1. Together, these observations indicate short-lived, specialized reinforcement in the spindle center. This could help protect chromosome attachments from transient forces while allowing spindle remodeling, and chromosome movements, over longer timescales.
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Affiliation(s)
- Pooja Suresh
- Biophysics Graduate Program, University of California, San FranciscoSan FranciscoUnited States
- Department of Cell and Tissue Biology, University of California, San FranciscoSan FranciscoUnited States
- Department of Bioengineering and Therapeutic Sciences, University of California, San FranciscoSan FranciscoUnited States
| | - Alexandra F Long
- Department of Cell and Tissue Biology, University of California, San FranciscoSan FranciscoUnited States
- Department of Bioengineering and Therapeutic Sciences, University of California, San FranciscoSan FranciscoUnited States
- Tetrad Graduate Program, University of California, San FranciscoSan FranciscoUnited States
| | - Sophie Dumont
- Biophysics Graduate Program, University of California, San FranciscoSan FranciscoUnited States
- Department of Cell and Tissue Biology, University of California, San FranciscoSan FranciscoUnited States
- Department of Bioengineering and Therapeutic Sciences, University of California, San FranciscoSan FranciscoUnited States
- Tetrad Graduate Program, University of California, San FranciscoSan FranciscoUnited States
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23
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O'Toole E, Morphew M, McIntosh JR. Electron tomography reveals aspects of spindle structure important for mechanical stability at metaphase. Mol Biol Cell 2019; 31:184-195. [PMID: 31825721 PMCID: PMC7001478 DOI: 10.1091/mbc.e19-07-0405] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
Metaphase spindles exert pole-directed forces on still-connected sister kinetochores. The spindle must counter these forces with extensive forces to prevent spindle collapse. In small spindles, kinetochore microtubules (KMTs) connect directly with the poles, and countering forces are supplied either by interdigitating MTs that form interpolar bundles or by astral MTs connected to the cell cortex. In bigger spindles, particularly those without structured poles, the origin of extensive forces is less obvious. We have used electron tomography of well-preserved metaphase cells to obtain structural evidence about interactions among different classes of MTs in metaphase spindles from Chlamydomonas rheinhardti and two strains of cultured mammalian cells. In all these spindles, KMTs approach close to and cross-bridge with the minus ends of non-KMTs, which form a framework that interdigitates near the spindle equator. Although this structure is not pole-connected, its organization suggests that it can support kinetochore tension. Analogous arrangements of MTs have been seen in even bigger spindles, such as metaphase spindles in Haemanthus endosperm and frog egg extracts. We present and discuss a hypothesis that rationalizes changes in spindle design with spindle size based on the negative exponential distribution of MT lengths in dynamically unstable populations of tubulin polymers.
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Affiliation(s)
- Eileen O'Toole
- Department of Molecular, Cellular, and Developmental Biology, University of Colorado, Boulder, Boulder, CO 80309
| | - Mary Morphew
- Department of Molecular, Cellular, and Developmental Biology, University of Colorado, Boulder, Boulder, CO 80309
| | - J Richard McIntosh
- Department of Molecular, Cellular, and Developmental Biology, University of Colorado, Boulder, Boulder, CO 80309
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24
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Vukušić K, Buđa R, Tolić IM. Force-generating mechanisms of anaphase in human cells. J Cell Sci 2019; 132:132/18/jcs231985. [DOI: 10.1242/jcs.231985] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
ABSTRACT
What forces drive chromosome segregation remains one of the most challenging questions in cell division. Even though the duration of anaphase is short, it is of utmost importance for genome fidelity that no mistakes are made. Seminal studies in model organisms have revealed different mechanisms operating during chromosome segregation in anaphase, but the translation of these mechanisms to human cells is not straightforward. Recent work has shown that kinetochore fiber depolymerization during anaphase A is largely motor independent, whereas spindle elongation during anaphase B is coupled to sliding of interpolar microtubules in human cells. In this Review, we discuss the current knowledge on the mechanisms of force generation by kinetochore, interpolar and astral microtubules. By combining results from numerous studies, we propose a comprehensive picture of the role of individual force-producing and -regulating proteins. Finally, by linking key concepts of anaphase to most recent data, we summarize the contribution of all proposed mechanisms to chromosome segregation and argue that sliding of interpolar microtubules and depolymerization at the kinetochore are the main drivers of chromosome segregation during early anaphase in human cells.
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Affiliation(s)
- Kruno Vukušić
- Division of Molecular Biology, Ruđer Bošković Institute, Bijenička cesta 54, 10000 Zagreb, Croatia
| | - Renata Buđa
- Division of Molecular Biology, Ruđer Bošković Institute, Bijenička cesta 54, 10000 Zagreb, Croatia
| | - Iva M. Tolić
- Division of Molecular Biology, Ruđer Bošković Institute, Bijenička cesta 54, 10000 Zagreb, Croatia
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25
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Leone M, Musa G, Engel FB. Cardiomyocyte binucleation is associated with aberrant mitotic microtubule distribution, mislocalization of RhoA and IQGAP3, as well as defective actomyosin ring anchorage and cleavage furrow ingression. Cardiovasc Res 2019. [PMID: 29522098 DOI: 10.1093/cvr/cvy056] [Citation(s) in RCA: 40] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Aims After birth mammalian cardiomyocytes initiate a last cell cycle which results in binucleation due to cytokinesis failure. Despite its importance for cardiac regenerative therapies, this process is poorly understood. Here, we aimed at a better understanding of the difference between cardiomyocyte proliferation and binucleation and providing a new tool to distinguish these two processes. Methods and results Monitoring of cell division by time-lapse imaging revealed that rat cardiomyocyte binucleation stems from a failure to properly ingress the cleavage furrow. Astral microtubule required for actomyosin ring anchorage and thus furrow ingression were not symmetrically distributed at the periphery of the equatorial region during anaphase in binucleating cardiomyocytes. Consequently, RhoA, the master regulator of actomyosin ring formation and constriction, non-muscle myosin IIB, a central component of the actomyosin ring, as well as IQGAP3 were abnormally localized during cytokinesis. In agreement with improper furrow ingression, binucleation in vitro and in vivo was associated with a failure of RhoA and IQGAP3 to localize to the stembody of the midbody. Conclusion Taken together, these results indicate that naturally occurring cytokinesis failure in primary cardiomyocytes is due to an aberrant mitotic microtubule apparatus resulting in inefficient anchorage of the actomyosin ring to the plasma cell membrane. Thus, cardiomyocyte binucleation and division can be discriminated by the analysis of RhoA as well as IQGAP3 localization.
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Affiliation(s)
- Marina Leone
- Department of Cardiac Development and Remodelling, Max Planck Institute for Heart and Lung Research, Parkstrasse 1, 61231 Bad Nauheim, Germany.,Experimental Renal and Cardiovascular Research, Department of Nephropathology, Institute of Pathology, Friedrich-Alexander-Universität Erlangen-Nürnberg, Schwabachanlage 12, 91054 Erlangen, Germany
| | - Gentian Musa
- Experimental Renal and Cardiovascular Research, Department of Nephropathology, Institute of Pathology, Friedrich-Alexander-Universität Erlangen-Nürnberg, Schwabachanlage 12, 91054 Erlangen, Germany
| | - Felix Benedikt Engel
- Department of Cardiac Development and Remodelling, Max Planck Institute for Heart and Lung Research, Parkstrasse 1, 61231 Bad Nauheim, Germany.,Experimental Renal and Cardiovascular Research, Department of Nephropathology, Institute of Pathology, Friedrich-Alexander-Universität Erlangen-Nürnberg, Schwabachanlage 12, 91054 Erlangen, Germany.,Muscle Research Center Erlangen
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26
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She ZY, Wei YL, Lin Y, Li YL, Lu MH. Mechanisms of the Ase1/PRC1/MAP65 family in central spindle assembly. Biol Rev Camb Philos Soc 2019; 94:2033-2048. [PMID: 31343816 DOI: 10.1111/brv.12547] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2018] [Revised: 06/27/2019] [Accepted: 07/03/2019] [Indexed: 01/08/2023]
Abstract
During cytokinesis, the organization of the spindle midzone and chromosome segregation is controlled by the central spindle, a microtubule cytoskeleton containing kinesin motors and non-motor microtubule-associated proteins. The anaphase spindle elongation 1/protein regulator of cytokinesis 1/microtubule associated protein 65 (Ase1/PRC1/MAP65) family of microtubule-bundling proteins are key regulators of central spindle assembly, mediating microtubule crosslinking and spindle elongation in the midzone. Ase1/PRC1/MAP65 serves as a complex regulatory platform for the recruitment of other midzone proteins at the spindle midzone. Herein, we summarize recent advances in understanding of the structural domains and molecular kinetics of the Ase1/PRC1/MAP65 family. We summarize the regulatory network involved in post-translational modifications of Ase1/PRC1 by cyclin-dependent kinase 1 (Cdk1), cell division cycle 14 (Cdc14) and Polo-like kinase 1 (Plk1) and also highlight multiple functions of Ase1/PRC1 in central spindle organization, spindle elongation and cytokinesis during cell division.
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Affiliation(s)
- Zhen-Yu She
- Department of Cell Biology and Genetics/Center for Cell and Developmental Biology, The School of Basic Medical Sciences, Fujian Medical University, Fuzhou, Fujian, 350108, China
| | - Ya-Lan Wei
- Department of Cell Biology and Genetics/Center for Cell and Developmental Biology, The School of Basic Medical Sciences, Fujian Medical University, Fuzhou, Fujian, 350108, China
| | - Yang Lin
- Department of Cell Biology and Genetics/Center for Cell and Developmental Biology, The School of Basic Medical Sciences, Fujian Medical University, Fuzhou, Fujian, 350108, China
| | - Yue-Ling Li
- Department of Cell Biology and Genetics/Center for Cell and Developmental Biology, The School of Basic Medical Sciences, Fujian Medical University, Fuzhou, Fujian, 350108, China
| | - Ming-Hui Lu
- Department of Cell Biology and Genetics/Center for Cell and Developmental Biology, The School of Basic Medical Sciences, Fujian Medical University, Fuzhou, Fujian, 350108, China
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27
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Helical Twist and Rotational Forces in the Mitotic Spindle. Biomolecules 2019; 9:biom9040132. [PMID: 30939864 PMCID: PMC6523234 DOI: 10.3390/biom9040132] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2019] [Revised: 03/24/2019] [Accepted: 03/28/2019] [Indexed: 01/14/2023] Open
Abstract
The mitotic spindle segregates chromosomes into two daughter cells during cell division. This process relies on the precise regulation of forces acting on chromosomes as the cell progresses through mitosis. The forces in the spindle are difficult to directly measure using the available experimental techniques. Here, we review the ideas and recent advances of how forces can be determined from the spindle shape. By using these approaches, it has been shown that tension and compression coexist along a single kinetochore fiber, which are balanced by a bridging fiber between sister kinetochore fibers. An extension of this approach to three dimensions revealed that microtubule bundles have rich shapes, and extend not simply like meridians on the Earth’s surface but, rather, twisted in a helical manner. Such complex shapes are due to rotational forces, which, in addition to linear forces, act in the spindle and may be generated by motor proteins such as kinesin-5. These findings open new questions for future studies, to understand the mechanisms of rotational forces and reveal their biological roles in cells.
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28
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Ughy B, Schmidthoffer I, Szilak L. Heparan sulfate proteoglycan (HSPG) can take part in cell division: inside and outside. Cell Mol Life Sci 2019; 76:865-871. [PMID: 30465083 PMCID: PMC11105504 DOI: 10.1007/s00018-018-2964-z] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2018] [Revised: 10/30/2018] [Accepted: 11/02/2018] [Indexed: 11/26/2022]
Abstract
Prior to the cytokinesis, the cell-matrix interactions should be disrupted, and the mitotic cells round up. Prerequisite of mitosis, the centrosomes duplicate, spindle fibers are generated and move away from each other to opposite sides of the cells marking the cell poles. Later, an invagination in the plasma membrane is formed a few minutes after anaphase. This furrow ingression is driven by a contractile actomyosin ring, whose assembly is regulated by RhoA GTPase. At the completion of cytokinesis, the two daughter cells are still connected by a thin intercellular bridge, which is subjected to abscission, as the terminal step of cytokinesis. Here, it is overviewed, how syndecan-4, a transmembrane, heparan sulfate proteoglycan, can contribute to these processes in a phosphorylation-dependent manner.
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Affiliation(s)
- Bettina Ughy
- Institute of Plant Biology, Biological Research Centre of the Hungarian Academy of Sciences, Szeged, 6726, Hungary
| | - Ildiko Schmidthoffer
- Antal Wittmann Crop, Animal and Food Sciences Multidisciplinary Doctoral School, Mosonmagyaróvár, 9200, Hungary
| | - Laszlo Szilak
- Szilak Laboratories Bioinformatics and Molecule-Design Ltd., Szeged, 6723, Hungary.
- Cereal Research Non-profit Ltd., Szeged, 6726, Hungary.
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29
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Mann BJ, Wadsworth P. Distribution of Eg5 and TPX2 in mitosis: Insight from CRISPR tagged cells. Cytoskeleton (Hoboken) 2018; 75:508-521. [DOI: 10.1002/cm.21486] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2018] [Revised: 07/11/2018] [Accepted: 07/30/2018] [Indexed: 11/07/2022]
Affiliation(s)
- B. J. Mann
- Department of Biology, Program in Molecular and Cellular Biology University of Massachusetts Amherst Massachusetts
| | - P. Wadsworth
- Department of Biology, Program in Molecular and Cellular Biology University of Massachusetts Amherst Massachusetts
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30
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Novak M, Polak B, Simunić J, Boban Z, Kuzmić B, Thomae AW, Tolić IM, Pavin N. The mitotic spindle is chiral due to torques within microtubule bundles. Nat Commun 2018; 9:3571. [PMID: 30177685 PMCID: PMC6120957 DOI: 10.1038/s41467-018-06005-7] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2018] [Accepted: 08/06/2018] [Indexed: 11/08/2022] Open
Abstract
Mitosis relies on forces generated in the spindle, a micro-machine composed of microtubules and associated proteins. Forces are required for the congression of chromosomes to the metaphase plate and their separation in anaphase. However, besides forces, torques may exist in the spindle, yet they have not been investigated. Here we show that the spindle is chiral. Chirality is evident from the finding that microtubule bundles in human spindles follow a left-handed helical path, which cannot be explained by forces but rather by torques. Kinesin-5 (Kif11/Eg5) inactivation abolishes spindle chirality. Our theoretical model predicts that bending and twisting moments may generate curved shapes of bundles. We found that bundles turn by about -2 deg µm-1 around the spindle axis, which we explain by a twisting moment of roughly -10 pNµm. We conclude that torques, in addition to forces, exist in the spindle and determine its chiral architecture.
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Grants
- This work was funded by the European Research Council (ERC Consolidator Grant, GA number 647077, granted to I.M.T.), Unity through Knowledge Fund (UKF, project 18/15, granted to N.P. and I.M.T.), and the European Social Fund (HR.3.2.01-0022, co-leader I.M.T.). We also acknowledge support from the QuantiXLie Centre of Excellence, a project cofinanced by the Croatian Government and European Union through the European Regional Development Fund - the Competitiveness and Cohesion Operational Programme (Grant KK.01.1.1.01.0004, element leader N.P.), and the Croatian Science Foundation (HRZZ, project IP-2014-09- 4753, granted to I.M.T.).
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Affiliation(s)
- Maja Novak
- Department of Physics, Faculty of Science, University of Zagreb, Bijenička cesta 32, 10000, Zagreb, Croatia
- Division of Molecular Biology, Ruđer Bošković Institute, Bijenička cesta 54, 10000, Zagreb, Croatia
| | - Bruno Polak
- Division of Molecular Biology, Ruđer Bošković Institute, Bijenička cesta 54, 10000, Zagreb, Croatia
| | - Juraj Simunić
- Division of Molecular Biology, Ruđer Bošković Institute, Bijenička cesta 54, 10000, Zagreb, Croatia
| | - Zvonimir Boban
- Department of Physics, Faculty of Science, University of Zagreb, Bijenička cesta 32, 10000, Zagreb, Croatia
| | - Barbara Kuzmić
- Division of Molecular Biology, Ruđer Bošković Institute, Bijenička cesta 54, 10000, Zagreb, Croatia
| | - Andreas W Thomae
- Walter Brendel Centre of Experimental Medicine and Core Facility Bioimaging at the Biomedical Center, University of Munich, 82152, Planegg-Martinsried, Germany
| | - Iva M Tolić
- Division of Molecular Biology, Ruđer Bošković Institute, Bijenička cesta 54, 10000, Zagreb, Croatia.
| | - Nenad Pavin
- Department of Physics, Faculty of Science, University of Zagreb, Bijenička cesta 32, 10000, Zagreb, Croatia.
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31
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Strunov A, Boldyreva LV, Andreyeva EN, Pavlova GA, Popova JV, Razuvaeva AV, Anders AF, Renda F, Pindyurin AV, Gatti M, Kiseleva E. Ultrastructural analysis of mitotic Drosophila S2 cells identifies distinctive microtubule and intracellular membrane behaviors. BMC Biol 2018; 16:68. [PMID: 29907103 PMCID: PMC6003134 DOI: 10.1186/s12915-018-0528-1] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2018] [Accepted: 05/08/2018] [Indexed: 12/31/2022] Open
Abstract
BACKGROUND S2 cells are one of the most widely used Drosophila melanogaster cell lines. A series of studies has shown that they are particularly suitable for RNAi-based screens aimed at the dissection of cellular pathways, including those controlling cell shape and motility, cell metabolism, and host-pathogen interactions. In addition, RNAi in S2 cells has been successfully used to identify many new mitotic genes that are conserved in the higher eukaryotes, and for the analysis of several aspects of the mitotic process. However, no detailed and complete description of S2 cell mitosis at the ultrastructural level has been done. Here, we provide a detailed characterization of all phases of S2 cell mitosis visualized by transmission electron microscopy (TEM). RESULTS We analyzed by TEM a random sample of 144 cells undergoing mitosis, focusing on intracellular membrane and microtubule (MT) behaviors. This unbiased approach provided a comprehensive ultrastructural view of the dividing cells, and allowed us to discover that S2 cells exhibit a previously uncharacterized behavior of intracellular membranes, involving the formation of a quadruple nuclear membrane in early prometaphase and its disassembly during late prometaphase. After nuclear envelope disassembly, the mitotic apparatus becomes encased by a discontinuous network of endoplasmic reticulum membranes, which associate with mitochondria, presumably to prevent their diffusion into the spindle area. We also observed a peculiar metaphase spindle organization. We found that kinetochores with attached k-fibers are almost invariably associated with lateral MT bundles that can be either interpolar bundles or k-fibers connected to a different kinetochore. This spindle organization is likely to favor chromosome alignment at metaphase and subsequent segregation during anaphase. CONCLUSIONS We discovered several previously unknown features of membrane and MT organization during S2 cell mitosis. The genetic determinants of these mitotic features can now be investigated, for instance by using an RNAi-based approach, which is particularly easy and efficient in S2 cells.
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Affiliation(s)
- Anton Strunov
- Institute of Molecular and Cellular Biology, Siberian Branch of RAS, Novosibirsk, 630090, Russia.
- Institute of Cytology and Genetics, Siberian Branch of RAS, Novosibirsk, 630090, Russia.
| | - Lidiya V Boldyreva
- Institute of Molecular and Cellular Biology, Siberian Branch of RAS, Novosibirsk, 630090, Russia
| | - Evgeniya N Andreyeva
- Institute of Molecular and Cellular Biology, Siberian Branch of RAS, Novosibirsk, 630090, Russia
| | - Gera A Pavlova
- Institute of Molecular and Cellular Biology, Siberian Branch of RAS, Novosibirsk, 630090, Russia
| | - Julia V Popova
- Institute of Molecular and Cellular Biology, Siberian Branch of RAS, Novosibirsk, 630090, Russia
- Institute of Cytology and Genetics, Siberian Branch of RAS, Novosibirsk, 630090, Russia
| | - Alena V Razuvaeva
- Institute of Molecular and Cellular Biology, Siberian Branch of RAS, Novosibirsk, 630090, Russia
- Novosibirsk State University, Novosibirsk, 630090, Russia
| | - Alina F Anders
- Institute of Molecular and Cellular Biology, Siberian Branch of RAS, Novosibirsk, 630090, Russia
- Novosibirsk State University, Novosibirsk, 630090, Russia
| | - Fioranna Renda
- IBPM CNR and Department of Biology and Biotechnology, Sapienza University of Rome, 00185, Rome, Italy
- Present address: Wadsworth Center, New York State Department of Health, Albany, NY, 12201, USA
| | - Alexey V Pindyurin
- Institute of Molecular and Cellular Biology, Siberian Branch of RAS, Novosibirsk, 630090, Russia
- Institute of Cytology and Genetics, Siberian Branch of RAS, Novosibirsk, 630090, Russia
- Novosibirsk State University, Novosibirsk, 630090, Russia
| | - Maurizio Gatti
- Institute of Molecular and Cellular Biology, Siberian Branch of RAS, Novosibirsk, 630090, Russia.
- IBPM CNR and Department of Biology and Biotechnology, Sapienza University of Rome, 00185, Rome, Italy.
| | - Elena Kiseleva
- Institute of Molecular and Cellular Biology, Siberian Branch of RAS, Novosibirsk, 630090, Russia
- Institute of Cytology and Genetics, Siberian Branch of RAS, Novosibirsk, 630090, Russia
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32
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Milas A, Jagrić M, Martinčić J, Tolić IM. Optogenetic reversible knocksideways, laser ablation, and photoactivation on the mitotic spindle in human cells. Methods Cell Biol 2018; 145:191-215. [DOI: 10.1016/bs.mcb.2018.03.024] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
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33
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Vukušić K, Buđa R, Bosilj A, Milas A, Pavin N, Tolić IM. Microtubule Sliding within the Bridging Fiber Pushes Kinetochore Fibers Apart to Segregate Chromosomes. Dev Cell 2017; 43:11-23.e6. [PMID: 29017027 PMCID: PMC5637169 DOI: 10.1016/j.devcel.2017.09.010] [Citation(s) in RCA: 67] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2017] [Revised: 07/21/2017] [Accepted: 09/13/2017] [Indexed: 01/06/2023]
Abstract
During cell division, mitotic spindle microtubules segregate chromosomes by exerting forces on kinetochores. What forces drive chromosome segregation in anaphase remains a central question. The current model for anaphase in human cells includes shortening of kinetochore fibers and separation of spindle poles. Both processes require kinetochores to be linked with the poles. Here we show, by combining laser ablation, photoactivation, and theoretical modeling, that kinetochores can separate without any attachment to one spindle pole. This separation requires the bridging fiber, a microtubule bundle that connects sister kinetochore fibers. Bridging fiber microtubules in intact spindles slide apart with kinetochore fibers, indicating strong crosslinks between them. We conclude that sliding of microtubules within the bridging fibers drives pole separation and pushes kinetochore fibers poleward by the friction of passive crosslinks between these fibers. Thus, sliding within the bridging fiber works together with the shortening of kinetochore fibers to segregate chromosomes.
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Affiliation(s)
- Kruno Vukušić
- Division of Molecular Biology, Ruđer Bošković Institute, Bijenička cesta 54, 10000 Zagreb, Croatia
| | - Renata Buđa
- Division of Molecular Biology, Ruđer Bošković Institute, Bijenička cesta 54, 10000 Zagreb, Croatia
| | - Agneza Bosilj
- Department of Physics, Faculty of Science, University of Zagreb, Bijenička cesta 32, 10000 Zagreb, Croatia
| | - Ana Milas
- Division of Molecular Biology, Ruđer Bošković Institute, Bijenička cesta 54, 10000 Zagreb, Croatia
| | - Nenad Pavin
- Department of Physics, Faculty of Science, University of Zagreb, Bijenička cesta 32, 10000 Zagreb, Croatia.
| | - Iva M Tolić
- Division of Molecular Biology, Ruđer Bošković Institute, Bijenička cesta 54, 10000 Zagreb, Croatia.
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