1
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Chang CC, Coyle SM. Regulatable assembly of synthetic microtubule architectures using engineered MAP-IDR condensates. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.03.14.532644. [PMID: 38105997 PMCID: PMC10723337 DOI: 10.1101/2023.03.14.532644] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/19/2023]
Abstract
Microtubules filaments are assembled into higher-order structures and machines critical for cellular processes using microtubule-associated proteins (MAPs). However, the design of synthetic MAPs that direct the formation of new structures in cells is challenging, as nanoscale biochemical activities must be organized across micron length-scales. Here we develop synthetic MAP-IDR condensates (synMAPs) that provide tunable and regulatable assembly of higher-order microtubule structures in vitro and in mammalian cells. synMAPs harness a small microtubule-binding domain from oligodendrocytes (TPPP) whose activity can be synthetically rewired by interaction with condensate-forming IDR sequences. This combination allows synMAPs to self-organize multivalent structures that bind and bridge microtubules into synthetic architectures. Regulating the connection between the microtubule-binding and condensate-forming components allows synMAPs to act as nodes in more complex cytoskeletal circuits in which the formation and dynamics of the microtubule structure can be controlled by small molecules or cell-signaling inputs. By systematically testing a panel of synMAP circuit designs, we define a two-level control scheme for dynamic assembly of microtubule architectures at the nanoscale (via microtubule-binding) and microscale (via condensate formation). synMAPs provide a compact and rationally engineerable starting point for the design of more complex microtubule architectures and cellular machines.
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Affiliation(s)
- Chih-Chia Chang
- Biophysics Graduate Program, University of Wisconsin-Madison, Madison, WI, 53705, USA
| | - Scott M. Coyle
- Biophysics Graduate Program, University of Wisconsin-Madison, Madison, WI, 53705, USA
- Department of Biochemistry, University of Wisconsin-Madison, Madison, WI, 53705, USA
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2
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Haruta N, Sumiyoshi E, Honda Y, Terasawa M, Uchiyama C, Toya M, Kubota Y, Sugimoto A. A germline-specific role for unconventional components of the γ-tubulin complex in Caenorhabditis elegans. J Cell Sci 2023; 136:jcs260922. [PMID: 37313686 PMCID: PMC10657210 DOI: 10.1242/jcs.260922] [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: 12/29/2022] [Accepted: 06/07/2023] [Indexed: 06/15/2023] Open
Abstract
The γ-tubulin complex (γTuC) is a widely conserved microtubule nucleator, but some of its components, namely GCP4, GCP5 and GCP6 (also known as TUBGCP4, TUBGCP5 and TUBGCP6, respectively), have not been detected in Caenorhabditis elegans. Here, we identified two γTuC-associated proteins in C. elegans, GTAP-1 and GTAP-2, for which apparent orthologs were detected only in the genus Caenorhabditis. GTAP-1 and GTAP-2 were found to localize at centrosomes and the plasma membrane of the germline, and their centrosomal localization was interdependent. In early C. elegans embryos, whereas the conserved γTuC component MZT-1 (also known as MOZART1 and MZT1) was essential for the localization of centrosomal γ-tubulin, depletion of GTAP-1 and/or GTAP-2 caused up to 50% reduction of centrosomal γ-tubulin and precocious disassembly of spindle poles during mitotic telophase. In the adult germline, GTAP-1 and GTAP-2 contributed to efficient recruitment of the γTuC to the plasma membrane. Depletion of GTAP-1, but not of GTAP-2, severely disrupted both the microtubule array and the honeycomb-like structure of the adult germline. We propose that GTAP-1 and GTAP-2 are unconventional components of the γTuC that contribute to the organization of both centrosomal and non-centrosomal microtubules by targeting the γTuC to specific subcellular sites in a tissue-specific manner.
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Affiliation(s)
- Nami Haruta
- Laboratory of Developmental Dynamics, Graduate School of Life Sciences, Tohoku University, Sendai 980-8577, Japan
| | - Eisuke Sumiyoshi
- Laboratory of Developmental Dynamics, Graduate School of Life Sciences, Tohoku University, Sendai 980-8577, Japan
| | - Yu Honda
- Laboratory of Developmental Dynamics, Graduate School of Life Sciences, Tohoku University, Sendai 980-8577, Japan
| | - Masahiro Terasawa
- Laboratory for Developmental Genomics, RIKEN Center for Developmental Biology, Kobe 650-0047, Japan
| | - Chihiro Uchiyama
- Laboratory of Developmental Dynamics, Graduate School of Life Sciences, Tohoku University, Sendai 980-8577, Japan
| | - Mika Toya
- Laboratory for Developmental Genomics, RIKEN Center for Developmental Biology, Kobe 650-0047, Japan
| | - Yukihiko Kubota
- Laboratory of Developmental Dynamics, Graduate School of Life Sciences, Tohoku University, Sendai 980-8577, Japan
| | - Asako Sugimoto
- Laboratory of Developmental Dynamics, Graduate School of Life Sciences, Tohoku University, Sendai 980-8577, Japan
- Laboratory for Developmental Genomics, RIKEN Center for Developmental Biology, Kobe 650-0047, Japan
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3
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Laguillo-Diego A, Kiewisz R, Martí-Gómez C, Baum D, Müller-Reichert T, Vernos I. MCRS1 modulates the heterogeneity of microtubule minus-end morphologies in mitotic spindles. Mol Biol Cell 2022; 34:ar1. [PMID: 36350698 PMCID: PMC9816640 DOI: 10.1091/mbc.e22-08-0306-t] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
Faithful chromosome segregation requires the assembly of a bipolar spindle, consisting of two antiparallel microtubule (MT) arrays having most of their minus ends focused at the spindle poles and their plus ends overlapping in the spindle midzone. Spindle assembly, chromosome alignment, and segregation require highly dynamic MTs. The plus ends of MTs have been extensively investigated but their minus-end structure remains poorly characterized. Here, we used large-scale electron tomography to study the morphology of the MT minus ends in three dimensionally reconstructed metaphase spindles in HeLa cells. In contrast to the homogeneous open morphology of the MT plus ends at the kinetochores, we found that MT minus ends are heterogeneous, showing either open or closed morphologies. Silencing the minus end-specific stabilizer, MCRS1 increased the proportion of open MT minus ends. Altogether, these data suggest a correlation between the morphology and the dynamic state of the MT ends. Taking this heterogeneity of the MT minus-end morphologies into account, our work indicates an unsynchronized behavior of MTs at the spindle poles, thus laying the groundwork for further studies on the complexity of MT dynamics regulation.
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Affiliation(s)
- Alejandra Laguillo-Diego
- Centre for Genomic Regulation, The Barcelona Institute of Science and Technology, Barcelona 08003, Spain
| | - Robert Kiewisz
- Experimental Center, Faculty of Medicine Carl Gustav Carus, Technische Universität Dresden, 01307 Dresden, Germany
| | - Carlos Martí-Gómez
- Simons Center for Quantitative Biology, Cold Spring Harbor Laboratory, Cold Spring Harbor, NY 11724
| | - Daniel Baum
- Department of Visual and Data-Centric Computing, Zuse Institute Berlin, 14195 Berlin, Germany
| | - Thomas Müller-Reichert
- Experimental Center, Faculty of Medicine Carl Gustav Carus, Technische Universität Dresden, 01307 Dresden, Germany
| | - Isabelle Vernos
- Centre for Genomic Regulation, The Barcelona Institute of Science and Technology, Barcelona 08003, Spain,Universitat Pompeu Fabra, Barcelona 08003, Spain,ICREA, Barcelona 08010, Spain,*Address correspondence to: Isabelle Vernos ()
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4
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Multiple asters organize the yolk microtubule network during dclk2-GFP zebrafish epiboly. Sci Rep 2022; 12:4072. [PMID: 35260695 PMCID: PMC8904445 DOI: 10.1038/s41598-022-07747-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2021] [Accepted: 02/21/2022] [Indexed: 11/25/2022] Open
Abstract
It is known that the organization of microtubule (MT) networks in cells is orchestrated by subcellular structures named MT organizing centers (MTOCs). In this work, we use Light Sheet Fluorescence and Confocal Microscopy to investigate how the MT network surrounding the spherical yolk is arranged in the dclk2-GFP zebrafish transgenic line. We found that during epiboly the MT network is organized by multiple aster-like MTOCS. These structures form rings around the yolk sphere. Importantly, in wt embryos, aster-like MTOCs are only found upon pharmacological or genetic induction. Using our microscopy approach, we underscore the variability in the number of such asters in the transgenic line and report on the variety of global configurations of the yolk MT network. The asters’ morphology, dynamics, and their distribution in the yolk sphere are also analyzed. We propose that these features are tightly linked to epiboly timing and geometry. Key molecules are identified which support this asters role as MTOCs, where MT nucleation and growth take place. We conclude that the yolk MT network of dclk2-GFP transgenic embryos can be used as a model to organize microtubules in a spherical geometry by means of multiple MTOCs.
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5
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Klebanovych A, Vinopal S, Dráberová E, Sládková V, Sulimenko T, Sulimenko V, Vosecká V, Macůrek L, Legido A, Dráber P. C53 Interacting with UFM1-Protein Ligase 1 Regulates Microtubule Nucleation in Response to ER Stress. Cells 2022; 11:cells11030555. [PMID: 35159364 PMCID: PMC8834445 DOI: 10.3390/cells11030555] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2021] [Revised: 01/27/2022] [Accepted: 02/03/2022] [Indexed: 02/01/2023] Open
Abstract
ER distribution depends on microtubules, and ER homeostasis disturbance activates the unfolded protein response resulting in ER remodeling. CDK5RAP3 (C53) implicated in various signaling pathways interacts with UFM1-protein ligase 1 (UFL1), which mediates the ufmylation of proteins in response to ER stress. Here we find that UFL1 and C53 associate with γ-tubulin ring complex proteins. Knockout of UFL1 or C53 in human osteosarcoma cells induces ER stress and boosts centrosomal microtubule nucleation accompanied by γ-tubulin accumulation, microtubule formation, and ER expansion. C53, which is stabilized by UFL1, associates with the centrosome and rescues microtubule nucleation in cells lacking UFL1. Pharmacological induction of ER stress by tunicamycin also leads to increased microtubule nucleation and ER expansion. Furthermore, tunicamycin suppresses the association of C53 with the centrosome. These findings point to a novel mechanism for the relief of ER stress by stimulation of centrosomal microtubule nucleation.
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Affiliation(s)
- Anastasiya Klebanovych
- Laboratory of Biology of Cytoskeleton, Institute of Molecular Genetics of the Czech Academy of Sciences, CZ 142 20 Prague, Czech Republic; (A.K.); (S.V.); (E.D.); (V.S.); (T.S.); (V.S.); (V.V.); (L.M.)
| | - Stanislav Vinopal
- Laboratory of Biology of Cytoskeleton, Institute of Molecular Genetics of the Czech Academy of Sciences, CZ 142 20 Prague, Czech Republic; (A.K.); (S.V.); (E.D.); (V.S.); (T.S.); (V.S.); (V.V.); (L.M.)
| | - Eduarda Dráberová
- Laboratory of Biology of Cytoskeleton, Institute of Molecular Genetics of the Czech Academy of Sciences, CZ 142 20 Prague, Czech Republic; (A.K.); (S.V.); (E.D.); (V.S.); (T.S.); (V.S.); (V.V.); (L.M.)
| | - Vladimíra Sládková
- Laboratory of Biology of Cytoskeleton, Institute of Molecular Genetics of the Czech Academy of Sciences, CZ 142 20 Prague, Czech Republic; (A.K.); (S.V.); (E.D.); (V.S.); (T.S.); (V.S.); (V.V.); (L.M.)
| | - Tetyana Sulimenko
- Laboratory of Biology of Cytoskeleton, Institute of Molecular Genetics of the Czech Academy of Sciences, CZ 142 20 Prague, Czech Republic; (A.K.); (S.V.); (E.D.); (V.S.); (T.S.); (V.S.); (V.V.); (L.M.)
| | - Vadym Sulimenko
- Laboratory of Biology of Cytoskeleton, Institute of Molecular Genetics of the Czech Academy of Sciences, CZ 142 20 Prague, Czech Republic; (A.K.); (S.V.); (E.D.); (V.S.); (T.S.); (V.S.); (V.V.); (L.M.)
| | - Věra Vosecká
- Laboratory of Biology of Cytoskeleton, Institute of Molecular Genetics of the Czech Academy of Sciences, CZ 142 20 Prague, Czech Republic; (A.K.); (S.V.); (E.D.); (V.S.); (T.S.); (V.S.); (V.V.); (L.M.)
| | - Libor Macůrek
- Laboratory of Biology of Cytoskeleton, Institute of Molecular Genetics of the Czech Academy of Sciences, CZ 142 20 Prague, Czech Republic; (A.K.); (S.V.); (E.D.); (V.S.); (T.S.); (V.S.); (V.V.); (L.M.)
| | - Agustin Legido
- Section of Neurology, St. Christopher’s Hospital for Children, Department of Pediatrics, Drexel University College of Medicine, Philadelphia, PA 19134, USA;
| | - Pavel Dráber
- Laboratory of Biology of Cytoskeleton, Institute of Molecular Genetics of the Czech Academy of Sciences, CZ 142 20 Prague, Czech Republic; (A.K.); (S.V.); (E.D.); (V.S.); (T.S.); (V.S.); (V.V.); (L.M.)
- Correspondence: ; Tel.: +420-241-062-632
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6
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Mascanzoni F, Iannitti R, Colanzi A. Functional Coordination among the Golgi Complex, the Centrosome and the Microtubule Cytoskeleton during the Cell Cycle. Cells 2022; 11:cells11030354. [PMID: 35159164 PMCID: PMC8834581 DOI: 10.3390/cells11030354] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2021] [Revised: 01/14/2022] [Accepted: 01/17/2022] [Indexed: 12/11/2022] Open
Abstract
The Golgi complex of mammalian cells is organized in a ribbon-like structure often closely associated with the centrosome during interphase. Conversely, the Golgi complex assumes a fragmented and dispersed configuration away from the centrosome during mitosis. The structure of the Golgi complex and the relative position to the centrosome are dynamically regulated by microtubules. Many pieces of evidence reveal that this microtubule-mediated dynamic association between the Golgi complex and centrosome is of functional significance in cell polarization and division. Here, we summarize findings indicating how the Golgi complex and the centrosome cooperate in organizing the microtubule network for the directional protein transport and centrosome positioning required for cell polarization and regulating fundamental cell division processes.
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7
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Khabudaev KV, Petrova DP, Bedoshvili YD, Likhoshway YV, Grachev MA. Molecular Evolution of Tubulins in Diatoms. Int J Mol Sci 2022; 23:618. [PMID: 35054799 PMCID: PMC8776100 DOI: 10.3390/ijms23020618] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2021] [Revised: 12/29/2021] [Accepted: 12/30/2021] [Indexed: 01/29/2023] Open
Abstract
Microtubules are formed by α- and β-tubulin heterodimers nucleated with γ-tubulin. Tubulins are conserved eukaryotic proteins. Previously, it was shown that microtubules are involved in diatom silica frustule morphogenesis. Diatom frustules are varied, and their morphology is species-specific. Despite the attractiveness of the problem of elucidating the molecular mechanisms of genetically programmed morphogenesis, the structure and evolution of diatom tubulins have not been studied previously. Based on available genomic and transcriptome data, we analyzed the phylogeny of the predicted amino acid sequences of diatom α-, β- and γ-tubulins and identified five groups for α-tubulins, six for β-tubulins and four for γ-tubulins. We identified characteristic amino acids of each of these groups and also analyzed possible posttranslational modification sites of diatom tubulins. According to our results, we assumed what changes occurred in the diatom tubulin structures during their evolution. We also identified which tubulin groups are inherent in large diatom taxa. The similarity between the evolution of diatom tubulins and the evolution of diatoms suggests that molecular changes in α-, β- and γ-tubulins could be one of the factors in the formation of a high morphological diversity of diatoms.
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Affiliation(s)
| | | | - Yekaterina D. Bedoshvili
- Limnological Institute, Siberian Branch, Russian Academy of Sciences, 664033 Irkutsk, Russia; (K.V.K.); (D.P.P.); (Y.V.L.); (M.A.G.)
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8
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Romeiro Motta M, Zhao X, Pastuglia M, Belcram K, Roodbarkelari F, Komaki M, Harashima H, Komaki S, Kumar M, Bulankova P, Heese M, Riha K, Bouchez D, Schnittger A. B1-type cyclins control microtubule organization during cell division in Arabidopsis. EMBO Rep 2022; 23:e53995. [PMID: 34882930 PMCID: PMC8728612 DOI: 10.15252/embr.202153995] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2021] [Revised: 10/11/2021] [Accepted: 10/14/2021] [Indexed: 11/09/2022] Open
Abstract
Flowering plants contain a large number of cyclin families, each containing multiple members, most of which have not been characterized to date. Here, we analyzed the role of the B1 subclass of mitotic cyclins in cell cycle control during Arabidopsis development. While we reveal CYCB1;5 to be a pseudogene, the remaining four members were found to be expressed in dividing cells. Mutant analyses showed a complex pattern of overlapping, development-specific requirements of B1-type cyclins with CYCB1;2 playing a central role. The double mutant cycb1;1 cycb1;2 is severely compromised in growth, yet viable beyond the seedling stage, hence representing a unique opportunity to study the function of B1-type cyclin activity at the organismic level. Immunolocalization of microtubules in cycb1;1 cycb1;2 and treating mutants with the microtubule drug oryzalin revealed a key role of B1-type cyclins in orchestrating mitotic microtubule networks. Subsequently, we identified the GAMMA-TUBULIN COMPLEX PROTEIN 3-INTERACTING PROTEIN 1 (GIP1/MOZART) as an in vitro substrate of B1-type cyclin complexes and further genetic analyses support a potential role in the regulation of GIP1 by CYCB1s.
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Affiliation(s)
| | - Xin’Ai Zhao
- Department of Developmental BiologyUniversity of HamburgHamburgGermany
- Centre for Organismal Studies HeidelbergUniversity of HeidelbergHeidelbergGermany
| | - Martine Pastuglia
- Institute Jean‐Pierre BourginINRAEAgroParisTechUniversité Paris‐SaclayVersaillesFrance
| | - Katia Belcram
- Institute Jean‐Pierre BourginINRAEAgroParisTechUniversité Paris‐SaclayVersaillesFrance
| | | | - Maki Komaki
- Department of Developmental BiologyUniversity of HamburgHamburgGermany
| | - Hirofumi Harashima
- RIKEN Center for Sustainable Resource ScienceYokohamaJapan
- Present address:
Solution Research LaboratoryAS ONE CorporationKawasakiJapan
| | - Shinichiro Komaki
- Department of Developmental BiologyUniversity of HamburgHamburgGermany
- Nara Institute of Science and TechnologyNaraJapan
| | - Manoj Kumar
- Amity Institute of Genome EngineeringAmity University Uttar PradeshSector 125NoidaIndia
| | | | - Maren Heese
- Department of Developmental BiologyUniversity of HamburgHamburgGermany
| | - Karel Riha
- Central European Institute of TechnologyMasaryk UniversityBrnoCzech Republic
| | - David Bouchez
- Institute Jean‐Pierre BourginINRAEAgroParisTechUniversité Paris‐SaclayVersaillesFrance
| | - Arp Schnittger
- Department of Developmental BiologyUniversity of HamburgHamburgGermany
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9
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Tomasina R, González FC, Francia ME. Structural and Functional Insights into the Microtubule Organizing Centers of Toxoplasma gondii and Plasmodium spp. Microorganisms 2021; 9:2503. [PMID: 34946106 PMCID: PMC8705618 DOI: 10.3390/microorganisms9122503] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2021] [Revised: 11/19/2021] [Accepted: 11/23/2021] [Indexed: 12/23/2022] Open
Abstract
Microtubule organizing centers (MTOCs) perform critical cellular tasks by nucleating, stabilizing, and anchoring microtubule's minus ends. These capacities impact tremendously a wide array of cellular functions ranging from ascribing cell shape to orchestrating cell division and generating motile structures, among others. The phylum Apicomplexa comprises over 6000 single-celled obligate intracellular parasitic species. Many of the apicomplexan are well known pathogens such as Toxoplasma gondii and the Plasmodium species, causative agents of toxoplasmosis and malaria, respectively. Microtubule organization in these parasites is critical for organizing the cortical cytoskeleton, enabling host cell penetration and the positioning of large organelles, driving cell division and directing the formation of flagella in sexual life stages. Apicomplexans are a prime example of MTOC diversity displaying multiple functional and structural MTOCs combinations within a single species. This diversity can only be fully understood in light of each organism's specific MT nucleation requirements and their evolutionary history. Insight into apicomplexan MTOCs had traditionally been limited to classical ultrastructural work by transmission electron microscopy. However, in the past few years, a large body of molecular insight has emerged. In this work we describe the latest insights into nuclear MTOC biology in two major human and animal disease causing Apicomplexans: Toxoplasma gondii and Plasmodium spp.
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Affiliation(s)
- Ramiro Tomasina
- Laboratory of Apicomplexan Biology, Institut Pasteur de Montevideo, Montevideo 11400, Uruguay; (R.T.); (F.C.G.)
- Departamento de Parasitología y Micología, Facultad de Medicina, Universidad de la República, Montevideo 11600, Uruguay
| | - Fabiana C. González
- Laboratory of Apicomplexan Biology, Institut Pasteur de Montevideo, Montevideo 11400, Uruguay; (R.T.); (F.C.G.)
- Departamento de Parasitología y Micología, Facultad de Medicina, Universidad de la República, Montevideo 11600, Uruguay
| | - Maria E. Francia
- Laboratory of Apicomplexan Biology, Institut Pasteur de Montevideo, Montevideo 11400, Uruguay; (R.T.); (F.C.G.)
- Departamento de Parasitología y Micología, Facultad de Medicina, Universidad de la República, Montevideo 11600, Uruguay
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10
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Becker R, Vergarajauregui S, Billing F, Sharkova M, Lippolis E, Mamchaoui K, Ferrazzi F, Engel FB. Myogenin controls via AKAP6 non-centrosomal microtubule-organizing center formation at the nuclear envelope. eLife 2021; 10:65672. [PMID: 34605406 PMCID: PMC8523159 DOI: 10.7554/elife.65672] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2020] [Accepted: 10/01/2021] [Indexed: 12/22/2022] Open
Abstract
Non-centrosomal microtubule-organizing centers (MTOCs) are pivotal for the function of multiple cell types, but the processes initiating their formation are unknown. Here, we find that the transcription factor myogenin is required in murine myoblasts for the localization of MTOC proteins to the nuclear envelope. Moreover, myogenin is sufficient in fibroblasts for nuclear envelope MTOC (NE-MTOC) formation and centrosome attenuation. Bioinformatics combined with loss- and gain-of-function experiments identified induction of AKAP6 expression as one central mechanism for myogenin-mediated NE-MTOC formation. Promoter studies indicate that myogenin preferentially induces the transcription of muscle- and NE-MTOC-specific isoforms of Akap6 and Syne1, which encodes nesprin-1α, the NE-MTOC anchor protein in muscle cells. Overexpression of AKAP6β and nesprin-1α was sufficient to recruit endogenous MTOC proteins to the nuclear envelope of myoblasts in the absence of myogenin. Taken together, our results illuminate how mammals transcriptionally control the switch from a centrosomal MTOC to an NE-MTOC and identify AKAP6 as a novel NE-MTOC component in muscle cells.
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Affiliation(s)
- Robert Becker
- Experimental Renal and Cardiovascular Research, Department of Nephropathology, Institute of Pathology, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Erlangen, Germany
| | - Silvia Vergarajauregui
- Experimental Renal and Cardiovascular Research, Department of Nephropathology, Institute of Pathology, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Erlangen, Germany
| | - Florian Billing
- Experimental Renal and Cardiovascular Research, Department of Nephropathology, Institute of Pathology, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Erlangen, Germany
| | - Maria Sharkova
- Experimental Renal and Cardiovascular Research, Department of Nephropathology, Institute of Pathology, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Erlangen, Germany
| | - Eleonora Lippolis
- Institute of Human Genetics, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany
| | - Kamel Mamchaoui
- Sorbonne Universités UPMC Université Paris 06, INSERM U974, CNRS FRE3617, Center for Research in Myology, GH Pitié Salpêtrière, 47 Boulevard de l'Hôpital, Paris, France
| | - Fulvia Ferrazzi
- Institute of Human Genetics, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany.,Department of Nephropathology, Institute of Pathology, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Erlangen, Germany.,Institute of Pathology, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Erlangen, Germany
| | - Felix B Engel
- Experimental Renal and Cardiovascular Research, Department of Nephropathology, Institute of Pathology, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Erlangen, Germany.,Muscle Research Center Erlangen (MURCE), Erlangen, Germany
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11
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Saha S, Unruh JR, Jaspersen SL. Distribution of γ-tubulin ring complex at the Schizosaccharomyces pombe spindle pole. MICROPUBLICATION BIOLOGY 2021; 2021:10.17912/micropub.biology.000464. [PMID: 35622906 PMCID: PMC9015813 DOI: 10.17912/micropub.biology.000464] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/27/2021] [Revised: 08/31/2021] [Accepted: 09/06/2021] [Indexed: 11/12/2022]
Abstract
Microtubule nucleation is mediated by the conserved γ-tubulin ring complex (γ-TuRC). Using super-resolution microscopy, we investigate the distribution of γ-TuRC components at the spindle pole body (SPB) in wild-type
Schizosaccharomyces pombe
. We observed asymmetric distribution of γ-TuRC on its nuclear and cytoplasmic surfaces, consistent with the uneven distribution of microtubules. Examination of deletion mutants in the three non-essential γ-TuRC subunits showed defects in γ-TuRC accumulation on the old and new SPB, particularly in cells lacking
alp16+
(the Gcp6 ortholog) that may explain the monopolar spindles observed in this mutant upon mitotic entry.
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Affiliation(s)
| | | | - Sue L Jaspersen
- Stowers Institute for Medical Research
,
Department of Molecular & Integrative Physiology, University of Kansas Medical Center
,
Correspondence to: Sue L Jaspersen (
)
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12
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Gao X, Herrero S, Wernet V, Erhardt S, Valerius O, Braus GH, Fischer R. The role of Aspergillus nidulans polo-like kinase PlkA in microtubule-organizing center control. J Cell Sci 2021; 134:271867. [PMID: 34328180 DOI: 10.1242/jcs.256537] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2020] [Accepted: 07/19/2021] [Indexed: 11/20/2022] Open
Abstract
Centrosomes are important microtubule-organizing centers (MTOC) in animal cells. In addition, non-centrosomal MTOCs (ncMTOCs) have been described in many cell types. The functional analogs of centrosomes in fungi are the spindle pole bodies (SPBs). In Aspergillus nidulans, additional MTOCs have been discovered at septa (sMTOC). Although the core components are conserved in both MTOCs, their composition and organization are different and dynamic. Here, we show that the polo-like kinase PlkA binds the γ-tubulin ring complex (γ-TuRC) receptor protein ApsB and contributes to targeting ApsB to both MTOCs. PlkA coordinates the activities of the SPB outer plaque and the sMTOC. PlkA kinase activity was required for astral MT formation involving ApsB recruitment. PlkA also interacted with the γ-TuRC inner plaque receptor protein PcpA. Mitosis was delayed without PlkA, and the PlkA protein was required for proper mitotic spindle morphology, although this function was independent of its catalytic activity. Our results suggest that the polo-like kinase is a regulator of MTOC activities and acts as a scaffolding unit through interaction with γ-TuRC receptors.
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Affiliation(s)
- Xiaolei Gao
- Karlsruhe Institute of Technology (KIT) - South Campus, Institute for Applied Biosciences, Dept. of Microbiology, Fritz-Haber-Weg 4, D-76131 Karlsruhe, Germany
| | - Saturnino Herrero
- Karlsruhe Institute of Technology (KIT) - South Campus, Institute for Applied Biosciences, Dept. of Microbiology, Fritz-Haber-Weg 4, D-76131 Karlsruhe, Germany
| | - Valentin Wernet
- Karlsruhe Institute of Technology (KIT) - South Campus, Institute for Applied Biosciences, Dept. of Microbiology, Fritz-Haber-Weg 4, D-76131 Karlsruhe, Germany
| | - Sylvia Erhardt
- Karlsruhe Institute of Technology (KIT) - South Campus, Zoological Institute, Fritz-Haber-Weg 4, D-76131 Karlsruhe, Germany
| | - Oliver Valerius
- University of Göttingen, Dept. of Microbiology, Justus-von-Liebig-Weg 11 37077 Göttingen, Germany
| | - Gerhard H Braus
- University of Göttingen, Dept. of Microbiology, Justus-von-Liebig-Weg 11 37077 Göttingen, Germany
| | - Reinhard Fischer
- Karlsruhe Institute of Technology (KIT) - South Campus, Institute for Applied Biosciences, Dept. of Microbiology, Fritz-Haber-Weg 4, D-76131 Karlsruhe, Germany
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13
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Yin C, Lui ESW, Jiang T, Qi RZ. Proteolysis of γ-tubulin small complex proteins is mediated by the ubiquitin-proteasome system. FEBS Lett 2021; 595:1987-1996. [PMID: 34107052 DOI: 10.1002/1873-3468.14146] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2021] [Revised: 05/23/2021] [Accepted: 06/02/2021] [Indexed: 11/12/2022]
Abstract
Microtubule nucleation is mainly mediated by the γ-tubulin ring complex (γTuRC), whose core components are γ-tubulin and γ-tubulin complex proteins GCP2-6. A substantial fraction of γ-tubulin also exists with GCP2 and GCP3 in a tetramer called the γ-tubulin small complex (γTuSC). To date, the mechanisms underlying the turnover of γ-tubulin and GCPs have remained unclear. Here, we show that γ-tubulin, GCP2, and GCP3 are proteolyzed by the ubiquitin-proteasome system, and we identify cullin 1, cullin 4A, and cullin 4B as the E3 ligases that mediate the ubiquitination and, consequently, the degradation of γ-tubulin. Notably, we found that γTuSC disassembly promotes the degradation of γ-tubulin, GCP2, and GCP3, which indicates a role for γTuSCs in the stabilization of its components.
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Affiliation(s)
- Can Yin
- Division of Life Science and State Key Laboratory of Molecular Neuroscience, The Hong Kong University of Science and Technology, China
| | - Edna S W Lui
- Division of Life Science and State Key Laboratory of Molecular Neuroscience, The Hong Kong University of Science and Technology, China
| | - Taolue Jiang
- Division of Life Science and State Key Laboratory of Molecular Neuroscience, The Hong Kong University of Science and Technology, China
| | - Robert Z Qi
- Division of Life Science and State Key Laboratory of Molecular Neuroscience, The Hong Kong University of Science and Technology, China
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14
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Tovey CA, Tsuji C, Egerton A, Bernard F, Guichet A, de la Roche M, Conduit PT. Autoinhibition of Cnn binding to γ-TuRCs prevents ectopic microtubule nucleation and cell division defects. J Cell Biol 2021; 220:212197. [PMID: 34042945 PMCID: PMC8164090 DOI: 10.1083/jcb.202010020] [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: 10/05/2020] [Revised: 03/25/2021] [Accepted: 05/05/2021] [Indexed: 12/22/2022] Open
Abstract
γ-Tubulin ring complexes (γ-TuRCs) nucleate microtubules. They are recruited to centrosomes in dividing cells via binding to N-terminal CM1 domains within γ-TuRC–tethering proteins, including Drosophila Centrosomin (Cnn). Binding promotes microtubule nucleation and is restricted to centrosomes in dividing cells, but the mechanism regulating binding remains unknown. Here, we identify an extreme N-terminal CM1 autoinhibition (CAI) domain found specifically within the centrosomal isoform of Cnn (Cnn-C) that inhibits γ-TuRC binding. Robust binding occurs after removal of the CAI domain or with the addition of phosphomimetic mutations, suggesting that phosphorylation helps relieve inhibition. We show that regulation of Cnn binding to γ-TuRCs is isoform specific and that misregulation of binding can result in ectopic cytosolic microtubules and major defects during cell division. We also find that human CDK5RAP2 is autoinhibited from binding γ-TuRCs, suggesting conservation across species. Overall, our results shed light on how and why CM1 domain binding to γ-TuRCs is regulated.
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Affiliation(s)
- Corinne A Tovey
- Department of Zoology, University of Cambridge, Cambridge, UK.,Université de Paris, Centre National de la Recherche Scientifique, Institut Jacques Monod, Paris, France
| | - Chisato Tsuji
- Department of Zoology, University of Cambridge, Cambridge, UK
| | - Alice Egerton
- Department of Zoology, University of Cambridge, Cambridge, UK
| | - Fred Bernard
- Université de Paris, Centre National de la Recherche Scientifique, Institut Jacques Monod, Paris, France
| | - Antoine Guichet
- Université de Paris, Centre National de la Recherche Scientifique, Institut Jacques Monod, Paris, France
| | - Marc de la Roche
- Department of Biochemistry, University of Cambridge, Cambridge, UK
| | - Paul T Conduit
- Department of Zoology, University of Cambridge, Cambridge, UK.,Université de Paris, Centre National de la Recherche Scientifique, Institut Jacques Monod, Paris, France
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15
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Brilot AF, Lyon AS, Zelter A, Viswanath S, Maxwell A, MacCoss MJ, Muller EG, Sali A, Davis TN, Agard DA. CM1-driven assembly and activation of yeast γ-tubulin small complex underlies microtubule nucleation. eLife 2021; 10:e65168. [PMID: 33949948 PMCID: PMC8099430 DOI: 10.7554/elife.65168] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2020] [Accepted: 04/12/2021] [Indexed: 01/08/2023] Open
Abstract
Microtubule (MT) nucleation is regulated by the γ-tubulin ring complex (γTuRC), conserved from yeast to humans. In Saccharomyces cerevisiae, γTuRC is composed of seven identical γ-tubulin small complex (γTuSC) sub-assemblies, which associate helically to template MT growth. γTuRC assembly provides a key point of regulation for the MT cytoskeleton. Here, we combine crosslinking mass spectrometry, X-ray crystallography, and cryo-EM structures of both monomeric and dimeric γTuSCs, and open and closed helical γTuRC assemblies in complex with Spc110p to elucidate the mechanisms of γTuRC assembly. γTuRC assembly is substantially aided by the evolutionarily conserved CM1 motif in Spc110p spanning a pair of adjacent γTuSCs. By providing the highest resolution and most complete views of any γTuSC assembly, our structures allow phosphorylation sites to be mapped, surprisingly suggesting that they are mostly inhibitory. A comparison of our structures with the CM1 binding site in the human γTuRC structure at the interface between GCP2 and GCP6 allows for the interpretation of significant structural changes arising from CM1 helix binding to metazoan γTuRC.
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Affiliation(s)
- Axel F Brilot
- Department of Biochemistry and Biophysics, University of California at San FranciscoSan FranciscoUnited States
| | - Andrew S Lyon
- Department of Biochemistry and Biophysics, University of California at San FranciscoSan FranciscoUnited States
| | - Alex Zelter
- Department of Biochemistry, University of WashingtonSeattleUnited States
| | - Shruthi Viswanath
- Department of Bioengineering and Therapeutic Sciences, University of California at San FranciscoSan FranciscoUnited States
| | - Alison Maxwell
- Department of Biochemistry and Biophysics, University of California at San FranciscoSan FranciscoUnited States
| | - Michael J MacCoss
- Department of Genome Sciences, University of WashingtonSeattleUnited States
| | - Eric G Muller
- Department of Biochemistry, University of WashingtonSeattleUnited States
| | - Andrej Sali
- Department of Bioengineering and Therapeutic Sciences, University of California at San FranciscoSan FranciscoUnited States
| | - Trisha N Davis
- Department of Biochemistry, University of WashingtonSeattleUnited States
| | - David A Agard
- Department of Biochemistry and Biophysics, University of California at San FranciscoSan FranciscoUnited States
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16
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To nucleate or not, that is the question in neurons. Neurosci Lett 2021; 751:135806. [PMID: 33705928 DOI: 10.1016/j.neulet.2021.135806] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2020] [Revised: 02/23/2021] [Accepted: 02/26/2021] [Indexed: 01/19/2023]
Abstract
Microtubules are the structural center of neurons, stretching in overlapping arrays from the cell body to the far reaches of axons and dendrites. They also act as the tracks for long-range transport mediated by dynein and kinesin motors. Transcription and most translation take place in the cell body, and newly made cargoes must be shipped from this site of synthesis to sites of function in axons and dendrites. This constant demand for transport means that the microtubule array must be present without gaps throughout the cell over the lifetime of the animal. This task is made slightly easier in many animals by the relatively long, stable microtubules present in neurons. However, even stable neuronal microtubules have ends that are dynamic, and individual microtubules typically last on the order of hours, while the neurons around them last a lifetime. "Birth" of new microtubules is therefore required to maintain the neuronal microtubule array. In this review we discuss the nucleation of new microtubules in axons and dendrites, including how and where they are nucleated. In addition, it is becoming clear that neuronal microtubule nucleation is highly regulated, with unexpected machinery impinging on the decision of whether nucleation sites are active or inactive through space and time.
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17
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Priyanga J, Guha G, Bhakta-Guha D. Microtubule motors in centrosome homeostasis: A target for cancer therapy? Biochim Biophys Acta Rev Cancer 2021; 1875:188524. [PMID: 33582170 DOI: 10.1016/j.bbcan.2021.188524] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2020] [Revised: 02/02/2021] [Accepted: 02/05/2021] [Indexed: 01/02/2023]
Abstract
Cancer is a grievous concern to human health, owing to a massive heterogeneity in its cause and impact. Dysregulation (numerical, positional and/or structural) of centrosomes is one of the notable factors among those that promote onset and progression of cancers. In a normal dividing cell, a pair of centrosomes forms two poles, thereby governing the formation of a bipolar spindle assembly. A large number of cancer cells, however, harbor supernumerary centrosomes, which mimic the bipolar arrangement in normal cells by centrosome clustering (CC) into two opposite poles, thus developing a pseudo-bipolar spindle assembly. Manipulation of centrosome homeostasis is the paramount pre-requisite for the evasive strategy of CC in cancers. Out of the varied factors that uphold centrosome integrity, microtubule motors (MiMos) play a critical role. Categorized as dyneins and kinesins, MiMos are involved in cohesion of centrosomes, and also facilitate the maintenance of the numerical, positional and structural integrity of centrosomes. Herein, we elucidate the decisive mechanisms undertaken by MiMos to mediate centrosome homeostasis, and how dysregulation of the same might lead to CC in cancer cells. Understanding the impact of MiMos on CC might open up avenues toward a credible therapeutic target against diverse cancers.
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Affiliation(s)
- J Priyanga
- Cellular Dyshomeostasis Laboratory (CDHL), School of Chemical and Bio Technology, SASTRA University, Thanjavur 613 401, Tamil Nadu, India
| | - Gunjan Guha
- Cellular Dyshomeostasis Laboratory (CDHL), School of Chemical and Bio Technology, SASTRA University, Thanjavur 613 401, Tamil Nadu, India.
| | - Dipita Bhakta-Guha
- Cellular Dyshomeostasis Laboratory (CDHL), School of Chemical and Bio Technology, SASTRA University, Thanjavur 613 401, Tamil Nadu, India.
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18
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Shakeel I, Basheer N, Hasan GM, Afzal M, Hassan MI. Polo-like Kinase 1 as an emerging drug target: structure, function and therapeutic implications. J Drug Target 2021; 29:168-184. [PMID: 32886539 DOI: 10.1080/1061186x.2020.1818760] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2020] [Revised: 08/04/2020] [Accepted: 08/29/2020] [Indexed: 12/22/2022]
Abstract
Polo-like kinase 1 (PLK1) is a conserved mitotic serine-threonine protein kinase, functions as a regulatory protein, and is involved in the progression of the mitotic cycle. It plays important roles in the regulation of cell division, maintenance of genome stability, in spindle assembly, mitosis, and DNA-damage response. PLK1 is consist of a N-terminal serine-threonine kinase domain, and a C-terminal Polo-box domain (regulatory site). The expression of PLK1 is controlled by transcription repressor in the G1 stage and transcription activators in the G2 stage of the cell cycle. Overexpression of PLK1 results in undermining of checkpoints causes excessive cellular division resulting in abnormal cell growth, leading to the development of cancer. Blocking the expression of PLK1 by an antibody, RNA interference, or kinase inhibitors, causes a subsequent reduction in the proliferation of tumour cells and induction of apoptosis in tumour cells without affecting the healthy cells, suggesting an attractive target for drug development. In this review, we discuss detailed information on expression, gene and protein structures, role in different diseases, and progress in the design and development of PLK1 inhibitors. We have performed an in-depth analysis of the PLK1 inhibitors and their therapeutic implications with special focus to the cancer therapeutics.
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Affiliation(s)
- Ilma Shakeel
- Department of Zoology, Aligarh Muslim University, Aligarh, India
| | - Neha Basheer
- Institute of Neuroimmunology, Slovak Republic Bratislava, Bratislava, Slovakia
| | - Gulam Mustafa Hasan
- Department of Biochemistry, College of Medicine, Prince Sattam Bin Abdulaziz University, Al-Kharj, Kingdom of Saudi Arabia
| | - Mohammad Afzal
- Department of Zoology, Aligarh Muslim University, Aligarh, India
| | - Md Imtaiyaz Hassan
- Centre for Interdisciplinary Research in Basic Sciences, Jamia Millia Islamia, New Delhi, India
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19
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Chinen T, Yamazaki K, Hashimoto K, Fujii K, Watanabe K, Takeda Y, Yamamoto S, Nozaki Y, Tsuchiya Y, Takao D, Kitagawa D. Centriole and PCM cooperatively recruit CEP192 to spindle poles to promote bipolar spindle assembly. J Cell Biol 2021; 220:e202006085. [PMID: 33443571 PMCID: PMC7812875 DOI: 10.1083/jcb.202006085] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2020] [Revised: 10/12/2020] [Accepted: 12/15/2020] [Indexed: 12/21/2022] Open
Abstract
The pericentriolar material (PCM) that accumulates around the centriole expands during mitosis and nucleates microtubules. Here, we show the cooperative roles of the centriole and PCM scaffold proteins, pericentrin and CDK5RAP2, in the recruitment of CEP192 to spindle poles during mitosis. Systematic depletion of PCM proteins revealed that CEP192, but not pericentrin and/or CDK5RAP2, was crucial for bipolar spindle assembly in HeLa, RPE1, and A549 cells with centrioles. Upon double depletion of pericentrin and CDK5RAP2, CEP192 that remained at centriole walls was sufficient for bipolar spindle formation. In contrast, through centriole removal, we found that pericentrin and CDK5RAP2 recruited CEP192 at the acentriolar spindle pole and facilitated bipolar spindle formation in mitotic cells with one centrosome. Furthermore, the perturbation of PLK1, a critical kinase for PCM assembly, efficiently suppressed bipolar spindle formation in mitotic cells with one centrosome. Overall, these data suggest that the centriole and PCM scaffold proteins cooperatively recruit CEP192 to spindle poles and facilitate bipolar spindle formation.
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Affiliation(s)
- Takumi Chinen
- Department of Physiological Chemistry, Graduate School of Pharmaceutical Science, The University of Tokyo, Bunkyo, Tokyo, Japan
| | - Kaho Yamazaki
- Department of Physiological Chemistry, Graduate School of Pharmaceutical Science, The University of Tokyo, Bunkyo, Tokyo, Japan
| | - Kaho Hashimoto
- Department of Physiological Chemistry, Graduate School of Pharmaceutical Science, The University of Tokyo, Bunkyo, Tokyo, Japan
| | - Ken Fujii
- Department of Molecular Genetics, Division of Centrosome Biology, National Institute of Genetics, Mishima, Shizuoka, Japan
- Department of Genetics, School of Life Science, The Graduate University for Advanced Studies (SOKENDAI), Mishima, Shizuoka, Japan
| | - Koki Watanabe
- Department of Physiological Chemistry, Graduate School of Pharmaceutical Science, The University of Tokyo, Bunkyo, Tokyo, Japan
| | - Yutaka Takeda
- Department of Physiological Chemistry, Graduate School of Pharmaceutical Science, The University of Tokyo, Bunkyo, Tokyo, Japan
| | - Shohei Yamamoto
- Department of Physiological Chemistry, Graduate School of Pharmaceutical Science, The University of Tokyo, Bunkyo, Tokyo, Japan
- Graduate Program in Bioscience, Graduate School of Science, University of Tokyo, Hongo, Tokyo, Japan
| | - Yuka Nozaki
- Department of Molecular Genetics, Division of Centrosome Biology, National Institute of Genetics, Mishima, Shizuoka, Japan
| | - Yuki Tsuchiya
- Department of Molecular Genetics, Division of Centrosome Biology, National Institute of Genetics, Mishima, Shizuoka, Japan
- Department of Genetics, School of Life Science, The Graduate University for Advanced Studies (SOKENDAI), Mishima, Shizuoka, Japan
| | - Daisuke Takao
- Department of Physiological Chemistry, Graduate School of Pharmaceutical Science, The University of Tokyo, Bunkyo, Tokyo, Japan
| | - Daiju Kitagawa
- Department of Physiological Chemistry, Graduate School of Pharmaceutical Science, The University of Tokyo, Bunkyo, Tokyo, Japan
- Department of Molecular Genetics, Division of Centrosome Biology, National Institute of Genetics, Mishima, Shizuoka, Japan
- Department of Genetics, School of Life Science, The Graduate University for Advanced Studies (SOKENDAI), Mishima, Shizuoka, Japan
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20
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Gungor S, Oktay Y, Hiz S, Aranguren-Ibáñez Á, Kalafatcilar I, Yaramis A, Karaca E, Yis U, Sonmezler E, Ekinci B, Aslan M, Yilmaz E, Özgör B, Balaraju S, Szabo N, Laurie S, Beltran S, MacArthur DG, Hathazi D, Töpf A, Roos A, Lochmuller H, Vernos I, Horvath R. Autosomal recessive variants in TUBGCP2 alter the γ-tubulin ring complex leading to neurodevelopmental disease. iScience 2021; 24:101948. [PMID: 33458610 PMCID: PMC7797523 DOI: 10.1016/j.isci.2020.101948] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2020] [Revised: 09/20/2020] [Accepted: 12/11/2020] [Indexed: 12/23/2022] Open
Abstract
Microtubules help building the cytoskeleton of neurons and other cells. Several components of the gamma-tubulin (γ-tubulin) complex have been previously reported in human neurodevelopmental diseases. We describe two siblings from a consanguineous Turkish family with dysmorphic features, developmental delay, brain malformation, and epilepsy carrying a homozygous mutation (p.Glu311Lys) in TUBGCP2 encoding the γ-tubulin complex 2 (GCP2) protein. This variant is predicted to disrupt the electrostatic interaction of GCP2 with GCP3. In primary fibroblasts carrying the variant, we observed a faint delocalization of γ-tubulin during the cell cycle but normal GCP2 protein levels. Through mass spectrometry, we observed dysregulation of multiple proteins involved in the assembly and organization of the cytoskeleton and the extracellular matrix, controlling cellular adhesion and of proteins crucial for neuronal homeostasis including axon guidance. In summary, our functional and proteomic studies link TUBGCP2 and the γ-tubulin complex to the development of the central nervous system in humans.
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Affiliation(s)
- Serdal Gungor
- Inonu University, Faculty of Medicine, Turgut Ozal Research Center, Department of Paediatric Neurology, Malatya, Turkey
| | - Yavuz Oktay
- Izmir Biomedicine and Genome Center, Dokuz Eylul University Health Campus, Izmir, Turkey
- Department of Medical Biology, Faculty of Medicine, Dokuz Eylul University and Izmir International Biomedicine and Genome Institute, Dokuz Eylul University, Izmir, Turkey
| | - Semra Hiz
- Izmir Biomedicine and Genome Center, Dokuz Eylul University Health Campus, Izmir, Turkey
- Dokuz Eylul University, Faculty of Medicine, Department of Pediatric Neurology Izmir, Turkey
| | - Álvaro Aranguren-Ibáñez
- Centre for Genomic Regulation (CRG), the Barcelona Institute of Science and Technology, Dr. Aiguader 88, Barcelona 08003, Spain
| | - Ipek Kalafatcilar
- Izmir Biomedicine and Genome Center, Dokuz Eylul University Health Campus, Izmir, Turkey
- Dokuz Eylul University, Faculty of Medicine, Department of Pediatric Neurology Izmir, Turkey
| | - Ahmet Yaramis
- Pediatric Neurology Clinic, Private Office, Diyarbakir, Turkey
| | - Ezgi Karaca
- Izmir Biomedicine and Genome Center, Dokuz Eylul University Health Campus, Izmir, Turkey
- Department of Medical Biology, Faculty of Medicine, Dokuz Eylul University and Izmir International Biomedicine and Genome Institute, Dokuz Eylul University, Izmir, Turkey
| | - Uluc Yis
- Dokuz Eylul University, Faculty of Medicine, Department of Pediatric Neurology Izmir, Turkey
| | - Ece Sonmezler
- Izmir Biomedicine and Genome Center, Dokuz Eylul University Health Campus, Izmir, Turkey
| | - Burcu Ekinci
- Izmir Biomedicine and Genome Center, Dokuz Eylul University Health Campus, Izmir, Turkey
| | - Mahmut Aslan
- Dokuz Eylul University, Faculty of Medicine, Department of Pediatric Neurology Izmir, Turkey
| | - Elmasnur Yilmaz
- Izmir Biomedicine and Genome Center, Dokuz Eylul University Health Campus, Izmir, Turkey
| | - Bilge Özgör
- Inonu University, Faculty of Medicine, Turgut Ozal Research Center, Department of Paediatric Neurology, Malatya, Turkey
| | - Sunitha Balaraju
- John Walton Muscular Dystrophy Research Centre, Institute of Translational and Clinical Research, Newcastle University, Newcastle upon Tyne, UK
- Department of Clinical Neurosciences, John Van Geest Cambridge Centre for Brain Repair, University of Cambridge School of Clinical Medicine, Robinson Way, Cambridge CB2 0PY, UK
| | - Nora Szabo
- Department of Clinical Neurosciences, John Van Geest Cambridge Centre for Brain Repair, University of Cambridge School of Clinical Medicine, Robinson Way, Cambridge CB2 0PY, UK
- Budai Children Hospital, Észak-Közép-budai Centrum, Új Szent János Kórház és Szakrendelő, Budapest, Hungary
| | - Steven Laurie
- CNAG-CRG, Centre for Genomic Regulation, Barcelona Institute of Science and Technology, Barcelona, Spain
| | - Sergi Beltran
- CNAG-CRG, Centre for Genomic Regulation, Barcelona Institute of Science and Technology, Barcelona, Spain
| | - Daniel G. MacArthur
- Analytic and Translational Genetics Unit, Massachusetts General Hospital, Boston, MA, USA
- Program in Medical and Population Genetics, Broad Institute of MIT and Harvard, Cambridge, MA, USA
| | - Denisa Hathazi
- Department of Clinical Neurosciences, John Van Geest Cambridge Centre for Brain Repair, University of Cambridge School of Clinical Medicine, Robinson Way, Cambridge CB2 0PY, UK
| | - Ana Töpf
- John Walton Muscular Dystrophy Research Centre, Institute of Translational and Clinical Research, Newcastle University, Newcastle upon Tyne, UK
| | - Andreas Roos
- Leibniz Institut für Analytische Wissenschaften, ISAS, Dortmund, Germany & Pediatric Neurology, University Hospital, University of Duisburg-Essen, Faculty of Medicine, Essen, Germany
| | - Hanns Lochmuller
- Children's Hospital of Eastern Ontario Research Institute; Division of Neurology, Department of Medicine, the Ottawa Hospital; and Brain and Mind Research Institute, University of Ottawa, Ottawa, Canada
| | - Isabelle Vernos
- Centre for Genomic Regulation (CRG), the Barcelona Institute of Science and Technology, Dr. Aiguader 88, Barcelona 08003, Spain
- Universitat Pompeu Fabra (UPF), Barcelona, Spain
- Institució Catalana de Recerca i Estudis Avançats (ICREA), Spain
| | - Rita Horvath
- John Walton Muscular Dystrophy Research Centre, Institute of Translational and Clinical Research, Newcastle University, Newcastle upon Tyne, UK
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21
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Liu P, Würtz M, Zupa E, Pfeffer S, Schiebel E. Microtubule nucleation: The waltz between γ-tubulin ring complex and associated proteins. Curr Opin Cell Biol 2020; 68:124-131. [PMID: 33190097 DOI: 10.1016/j.ceb.2020.10.004] [Citation(s) in RCA: 36] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2020] [Revised: 09/22/2020] [Accepted: 10/08/2020] [Indexed: 12/31/2022]
Abstract
Microtubules are essential cytoskeletal elements assembled from αβ-tubulin dimers. In high eukaryotes, microtubule nucleation, the de novo assembly of a microtubule from its minus end, is initiated by the γ-tubulin ring complex (γ-TuRC). Despite many years of research, the structural and mechanistic principles of the microtubule nucleation machinery remained poorly understood. Only recently, cryoelectron microscopy studies uncovered the molecular organization and potential activation mechanisms of γ-TuRC. In vitro assays further deciphered the spatial and temporal cooperation between γ-TuRC and additional factors, for example, the augmin complex, the phase separation protein TPX2, and the microtubule polymerase XMAP215. These breakthroughs deepen our understanding of microtubule nucleation mechanisms and will link the assembly of individual microtubules to the organization of cellular microtubule networks.
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Affiliation(s)
- Peng Liu
- Zentrum für Molekulare Biologie der Universität Heidelberg (ZMBH), Im Neuenheimer Feld 282, D-69120, Heidelberg, Germany.
| | - Martin Würtz
- Zentrum für Molekulare Biologie der Universität Heidelberg (ZMBH), Im Neuenheimer Feld 282, D-69120, Heidelberg, Germany
| | - Erik Zupa
- Zentrum für Molekulare Biologie der Universität Heidelberg (ZMBH), Im Neuenheimer Feld 282, D-69120, Heidelberg, Germany
| | - Stefan Pfeffer
- Zentrum für Molekulare Biologie der Universität Heidelberg (ZMBH), Im Neuenheimer Feld 282, D-69120, Heidelberg, Germany
| | - Elmar Schiebel
- Zentrum für Molekulare Biologie der Universität Heidelberg (ZMBH), Im Neuenheimer Feld 282, D-69120, Heidelberg, Germany
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22
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Ma D, Han R. Microtubule organization defects in Arabidopsis thaliana. PLANT BIOLOGY (STUTTGART, GERMANY) 2020; 22:971-980. [PMID: 32215997 DOI: 10.1111/plb.13114] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/02/2020] [Accepted: 03/12/2020] [Indexed: 05/15/2023]
Abstract
Microtubules (MT) are critical cytoskeletal filaments that have several functions in cell morphogenesis, cell division, vesicle transport and cytoplasmic separation in the spatiotemporal regulation of eukaryotic cells. Formation of MT requires the co-interaction of MT nucleation and α-β-tubulins, as well as MT-associated proteins (MAP). Many key MAP contributing to MT nucleation and elongation are essential for MT nucleation and regulation of MT dynamics, and are conserved in the plant kingdom. Therefore, the deletion or decrease of γ-tubulin ring complex (γTuRC) components and related MAP, such as the augmin complex, NEDD1, MZT1, EB1, MAP65, etc., in Arabidopsis thaliana results in MT organizational defects in the spindle and phragmoplast MT, as well as in chromosome defects. In addition, similar defects in MT organization and chromosome structure have been observed in plants under abiotic stress conditions, such as under high UV-B radiation. The MT can sense the signal from UV-B radiation, resulting in abnormal MT arrangement. Further studies are required to determine whether the abnormal chromosomes induced by UV-B radiation can be attributed to the involvement of abnormal MT arrays in chromosome migration after DNA damage.
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Affiliation(s)
- D Ma
- College of Life Science, Shanxi Normal University, Linfen, China
- Higher Education Key Laboratory of Plant Molecular and Environmental Stress Response (Shanxi Normal University) in Shanxi Province, Linfen, China
| | - R Han
- College of Life Science, Shanxi Normal University, Linfen, China
- Higher Education Key Laboratory of Plant Molecular and Environmental Stress Response (Shanxi Normal University) in Shanxi Province, Linfen, China
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23
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Bergmann L, Lang A, Bross C, Altinoluk-Hambüchen S, Fey I, Overbeck N, Stefanski A, Wiek C, Kefalas A, Verhülsdonk P, Mielke C, Sohn D, Stühler K, Hanenberg H, Jänicke RU, Scheller J, Reichert AS, Ahmadian MR, Piekorz RP. Subcellular Localization and Mitotic Interactome Analyses Identify SIRT4 as a Centrosomally Localized and Microtubule Associated Protein. Cells 2020; 9:E1950. [PMID: 32846968 PMCID: PMC7564595 DOI: 10.3390/cells9091950] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2020] [Revised: 08/14/2020] [Accepted: 08/21/2020] [Indexed: 02/07/2023] Open
Abstract
The stress-inducible and senescence-associated tumor suppressor SIRT4, a member of the family of mitochondrial sirtuins (SIRT3, SIRT4, and SIRT5), regulates bioenergetics and metabolism via NAD+-dependent enzymatic activities. Next to the known mitochondrial location, we found that a fraction of endogenous or ectopically expressed SIRT4, but not SIRT3, is present in the cytosol and predominantly localizes to centrosomes. Confocal spinning disk microscopy revealed that SIRT4 is found during the cell cycle dynamically at centrosomes with an intensity peak in G2 and early mitosis. Moreover, SIRT4 precipitates with microtubules and interacts with structural (α,β-tubulin, γ-tubulin, TUBGCP2, TUBGCP3) and regulatory (HDAC6) microtubule components as detected by co-immunoprecipitation and mass spectrometric analyses of the mitotic SIRT4 interactome. Overexpression of SIRT4 resulted in a pronounced decrease of acetylated α-tubulin (K40) associated with altered microtubule dynamics in mitotic cells. SIRT4 or the N-terminally truncated variant SIRT4(ΔN28), which is unable to translocate into mitochondria, delayed mitotic progression and reduced cell proliferation. This study extends the functional roles of SIRT4 beyond mitochondrial metabolism and provides the first evidence that SIRT4 acts as a novel centrosomal/microtubule-associated protein in the regulation of cell cycle progression. Thus, stress-induced SIRT4 may exert its role as tumor suppressor through mitochondrial as well as extramitochondrial functions, the latter associated with its localization at the mitotic spindle apparatus.
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Affiliation(s)
- Laura Bergmann
- Institute of Biochemistry and Molecular Biology II, Medical Faculty, Heinrich Heine University Düsseldorf, 40225 Düsseldorf, Germany
| | - Alexander Lang
- Institute of Biochemistry and Molecular Biology II, Medical Faculty, Heinrich Heine University Düsseldorf, 40225 Düsseldorf, Germany
| | - Christoph Bross
- Institute of Biochemistry and Molecular Biology II, Medical Faculty, Heinrich Heine University Düsseldorf, 40225 Düsseldorf, Germany
| | - Simone Altinoluk-Hambüchen
- Institute of Biochemistry and Molecular Biology II, Medical Faculty, Heinrich Heine University Düsseldorf, 40225 Düsseldorf, Germany
| | - Iris Fey
- Institute of Biochemistry and Molecular Biology II, Medical Faculty, Heinrich Heine University Düsseldorf, 40225 Düsseldorf, Germany
| | - Nina Overbeck
- Molecular Proteomics Laboratory, Heinrich Heine University Düsseldorf, 40225 Düsseldorf, Germany
| | - Anja Stefanski
- Molecular Proteomics Laboratory, Heinrich Heine University Düsseldorf, 40225 Düsseldorf, Germany
| | - Constanze Wiek
- Department of Otolaryngology and Head/Neck Surgery, Medical Faculty, Heinrich Heine University Düsseldorf, 40225 Düsseldorf, Germany
| | - Andreas Kefalas
- Institute of Biochemistry and Molecular Biology II, Medical Faculty, Heinrich Heine University Düsseldorf, 40225 Düsseldorf, Germany
| | - Patrick Verhülsdonk
- Institute of Biochemistry and Molecular Biology II, Medical Faculty, Heinrich Heine University Düsseldorf, 40225 Düsseldorf, Germany
| | - Christian Mielke
- Institute of Clinical Chemistry and Laboratory Diagnostics, Medical Faculty, Heinrich Heine University Düsseldorf, 40225 Düsseldorf, Germany
| | - Dennis Sohn
- Laboratory of Molecular Radiooncology, Clinic and Policlinic for Radiation Therapy and Radiooncology, Medical Faculty, Heinrich Heine University Düsseldorf, 40225 Düsseldorf, Germany
| | - Kai Stühler
- Molecular Proteomics Laboratory, Heinrich Heine University Düsseldorf, 40225 Düsseldorf, Germany
- Institute for Molecular Medicine I, Medical Faculty, Heinrich Heine University Düsseldorf, 40225 Düsseldorf, Germany
| | - Helmut Hanenberg
- Department of Otolaryngology and Head/Neck Surgery, Medical Faculty, Heinrich Heine University Düsseldorf, 40225 Düsseldorf, Germany
- Department of Pediatrics III, University Hospital Essen, University Duisburg-Essen, 45112 Essen, Germany
| | - Reiner U Jänicke
- Laboratory of Molecular Radiooncology, Clinic and Policlinic for Radiation Therapy and Radiooncology, Medical Faculty, Heinrich Heine University Düsseldorf, 40225 Düsseldorf, Germany
| | - Jürgen Scheller
- Institute of Biochemistry and Molecular Biology II, Medical Faculty, Heinrich Heine University Düsseldorf, 40225 Düsseldorf, Germany
| | - Andreas S Reichert
- Institute of Biochemistry and Molecular Biology I, Medical Faculty, Heinrich Heine University Düsseldorf, 40225 Düsseldorf, Germany
| | - Mohammad Reza Ahmadian
- Institute of Biochemistry and Molecular Biology II, Medical Faculty, Heinrich Heine University Düsseldorf, 40225 Düsseldorf, Germany
| | - Roland P Piekorz
- Institute of Biochemistry and Molecular Biology II, Medical Faculty, Heinrich Heine University Düsseldorf, 40225 Düsseldorf, Germany
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24
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Mukherjee A, Brooks PS, Bernard F, Guichet A, Conduit PT. Microtubules originate asymmetrically at the somatic golgi and are guided via Kinesin2 to maintain polarity within neurons. eLife 2020; 9:e58943. [PMID: 32657758 PMCID: PMC7394546 DOI: 10.7554/elife.58943] [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: 05/15/2020] [Accepted: 07/12/2020] [Indexed: 12/12/2022] Open
Abstract
Neurons contain polarised microtubule arrays essential for neuronal function. How microtubule nucleation and polarity are regulated within neurons remains unclear. We show that γ-tubulin localises asymmetrically to the somatic Golgi within Drosophila neurons. Microtubules originate from the Golgi with an initial growth preference towards the axon. Their growing plus ends also turn towards and into the axon, adding to the plus-end-out microtubule pool. Any plus ends that reach a dendrite, however, do not readily enter, maintaining minus-end-out polarity. Both turning towards the axon and exclusion from dendrites depend on Kinesin-2, a plus-end-associated motor that guides growing plus ends along adjacent microtubules. We propose that Kinesin-2 engages with a polarised microtubule network within the soma to guide growing microtubules towards the axon; while at dendrite entry sites engagement with microtubules of opposite polarity generates a backward stalling force that prevents entry into dendrites and thus maintains minus-end-out polarity within proximal dendrites.
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Affiliation(s)
- Amrita Mukherjee
- Department of Zoology, University of CambridgeCambridgeUnited Kingdom
| | - Paul S Brooks
- Department of Zoology, University of CambridgeCambridgeUnited Kingdom
| | - Fred Bernard
- Université de Paris, CNRS, Institut Jacques MonodParisFrance
| | - Antoine Guichet
- Université de Paris, CNRS, Institut Jacques MonodParisFrance
| | - Paul T Conduit
- Department of Zoology, University of CambridgeCambridgeUnited Kingdom
- Université de Paris, CNRS, Institut Jacques MonodParisFrance
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25
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Shintani K, Ebisu H, Mukaiyama M, Hatanaka T, Chinen T, Takao D, Nagumo Y, Sakakura A, Hayakawa I, Usui T. Structure Optimization of Gatastatin for the Development of γ-Tubulin-Specific Inhibitor. ACS Med Chem Lett 2020; 11:1125-1129. [PMID: 32550991 DOI: 10.1021/acsmedchemlett.9b00526] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2019] [Accepted: 03/30/2020] [Indexed: 02/02/2023] Open
Abstract
Gatastatin (O 7-benzyl glaziovianin A) is a γ-tubulin-specific inhibitor that is used to investigate γ-tubulin function in cells. We have previously reported that the unsubstituted phenyl ring of the O 7-benzyl group in gatastatin is important for γ-tubulin inhibition. To obtain further structural information regarding γ-tubulin inhibition, we synthesized several gatastatin derivatives containing a fixed O 7-benzyl moiety. Modifications of the B-ring resulted in drastic decrease in cytotoxicity, abnormal spindle formation activity, and inhibition of microtubule (MT) nucleation. In contrast, various O 6-alkylated gatastatin derivatives showed potent cytotoxicity, induced abnormal spindle formation, and inhibited MT nucleation. We had previously reported that O 6-benzyl glaziovianin A is a potent α/β-tubulin inhibitor; thus, these new results suggest that the O 6-position restricts affinity for α/β- and γ-tubulin. Considering that an O 7-benzyl group increases specificity for γ-tubulin, more potent and specific γ-tubulin inhibitors can be generated through O 6-modifications of gatastatin.
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Affiliation(s)
| | | | | | - Taisei Hatanaka
- Division of Applied Chemistry, Graduate School of Natural Science and Technology, Okayama University, 3-1-1 Tsushima-naka, Kita-ku, Okayama 700-8530, Japan
| | - Takumi Chinen
- Graduate School of Pharmaceutical Sciences, The University of Tokyo, Bunkyo, Tokyo 113-0033, Japan
| | - Daisuke Takao
- Graduate School of Pharmaceutical Sciences, The University of Tokyo, Bunkyo, Tokyo 113-0033, Japan
| | | | - Akira Sakakura
- Division of Applied Chemistry, Graduate School of Natural Science and Technology, Okayama University, 3-1-1 Tsushima-naka, Kita-ku, Okayama 700-8530, Japan
| | - Ichiro Hayakawa
- Division of Applied Chemistry, Graduate School of Natural Science and Technology, Okayama University, 3-1-1 Tsushima-naka, Kita-ku, Okayama 700-8530, Japan
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26
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Consolati T, Locke J, Roostalu J, Chen ZA, Gannon J, Asthana J, Lim WM, Martino F, Cvetkovic MA, Rappsilber J, Costa A, Surrey T. Microtubule Nucleation Properties of Single Human γTuRCs Explained by Their Cryo-EM Structure. Dev Cell 2020; 53:603-617.e8. [PMID: 32433913 PMCID: PMC7280788 DOI: 10.1016/j.devcel.2020.04.019] [Citation(s) in RCA: 72] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2019] [Revised: 03/21/2020] [Accepted: 04/27/2020] [Indexed: 12/13/2022]
Abstract
The γ-tubulin ring complex (γTuRC) is the major microtubule nucleator in cells. The mechanism of its regulation is not understood. We purified human γTuRC and measured its nucleation properties in a total internal reflection fluorescence (TIRF) microscopy-based real-time nucleation assay. We find that γTuRC stably caps the minus ends of microtubules that it nucleates stochastically. Nucleation is inefficient compared with microtubule elongation. The 4 Å resolution cryoelectron microscopy (cryo-EM) structure of γTuRC, combined with crosslinking mass spectrometry analysis, reveals an asymmetric conformation with only part of the complex in a "closed" conformation matching the microtubule geometry. Actin in the core of the complex, and MZT2 at the outer perimeter of the closed part of γTuRC appear to stabilize the closed conformation. The opposite side of γTuRC is in an "open," nucleation-incompetent conformation, leading to a structural asymmetry explaining the low nucleation efficiency of purified human γTuRC. Our data suggest possible regulatory mechanisms for microtubule nucleation by γTuRC closure.
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Affiliation(s)
- Tanja Consolati
- The Francis Crick Institute, 1 Midland Road, London NW1 1AT, UK; Centre for Genomic Regulation (CRG), Barcelona Institute of Science and Technology (BIST), Dr Aiguader 88, 08003 Barcelona, Spain
| | - Julia Locke
- The Francis Crick Institute, 1 Midland Road, London NW1 1AT, UK
| | | | - Zhuo Angel Chen
- Bioanalytics, Institute of Biotechnology, Technische Universität Berlin, Berlin, Germany; Wellcome Centre for Cell Biology, University of Edinburgh, Edinburgh, UK
| | - Julian Gannon
- The Francis Crick Institute, 1 Midland Road, London NW1 1AT, UK
| | - Jayant Asthana
- The Francis Crick Institute, 1 Midland Road, London NW1 1AT, UK; Centre for Genomic Regulation (CRG), Barcelona Institute of Science and Technology (BIST), Dr Aiguader 88, 08003 Barcelona, Spain
| | - Wei Ming Lim
- The Francis Crick Institute, 1 Midland Road, London NW1 1AT, UK; Centre for Genomic Regulation (CRG), Barcelona Institute of Science and Technology (BIST), Dr Aiguader 88, 08003 Barcelona, Spain
| | | | | | - Juri Rappsilber
- Bioanalytics, Institute of Biotechnology, Technische Universität Berlin, Berlin, Germany; Wellcome Centre for Cell Biology, University of Edinburgh, Edinburgh, UK
| | - Alessandro Costa
- The Francis Crick Institute, 1 Midland Road, London NW1 1AT, UK.
| | - Thomas Surrey
- The Francis Crick Institute, 1 Midland Road, London NW1 1AT, UK; Centre for Genomic Regulation (CRG), Barcelona Institute of Science and Technology (BIST), Dr Aiguader 88, 08003 Barcelona, Spain; ICREA, Passeig de Lluis Companys 23, 08010 Barcelona, Spain.
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27
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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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28
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Promiscuous Binding of Microprotein Mozart1 to γ-Tubulin Complex Mediates Specific Subcellular Targeting to Control Microtubule Array Formation. Cell Rep 2020; 31:107836. [DOI: 10.1016/j.celrep.2020.107836] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2019] [Revised: 06/02/2020] [Accepted: 06/09/2020] [Indexed: 12/24/2022] Open
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29
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Rolls MM, Thyagarajan P, Feng C. Microtubule dynamics in healthy and injured neurons. Dev Neurobiol 2020; 81:321-332. [PMID: 32291942 DOI: 10.1002/dneu.22746] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2019] [Revised: 01/22/2020] [Accepted: 04/08/2020] [Indexed: 12/28/2022]
Abstract
Most neurons must last a lifetime and their microtubule cytoskeleton is an important contributor to their longevity. Neurons have some of the most stable microtubules of all cells, but the tip of every microtubule remains dynamic and, although requiring constant GTP consumption, microtubules are always being rebuilt. While some ongoing level of rebuilding always occurs, overall microtubule stability can be modulated in response to injury and stress as well as the normal developmental process of pruning. Specific microtubule severing proteins act in different contexts to increase microtubule dynamicity and promote degeneration and pruning. After axon injury, complex changes in dynamics occur and these are important for both neuroprotection induced by injury and subsequent outgrowth of a new axon. Understanding how microtubule dynamics is modulated in different scenarios, as well as the impact of the changes in stability, is an important avenue to explore for development of strategies to promote neuroprotection and regeneration.
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Affiliation(s)
- Melissa M Rolls
- Biochemistry and Molecular Biology and Huck Institutes of the Life Sciences, The Pennsylvania State University, University Park, PA, USA
| | - Pankajam Thyagarajan
- Biochemistry and Molecular Biology and Huck Institutes of the Life Sciences, The Pennsylvania State University, University Park, PA, USA
| | - Chengye Feng
- Biochemistry and Molecular Biology and Huck Institutes of the Life Sciences, The Pennsylvania State University, University Park, PA, USA
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30
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The γ-tubulin complex protein GCP6 is crucial for spindle morphogenesis but not essential for microtubule reorganization in Arabidopsis. Proc Natl Acad Sci U S A 2019; 116:27115-27123. [PMID: 31818952 DOI: 10.1073/pnas.1912240116] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
γ-Tubulin typically forms a ring-shaped complex with 5 related γ-tubulin complex proteins (GCP2 to GCP6), and this γ-tubulin ring complex (γTuRC) serves as a template for microtubule (MT) nucleation in plants and animals. While the γTuRC takes part in MT nucleation in most eukaryotes, in fungi such events take place robustly with just the γ-tubulin small complex (γTuSC) assembled by γ-tubulin plus GCP2 and GCP3. To explore whether the γTuRC is the sole functional γ-tubulin complex in plants, we generated 2 mutants of the GCP6 gene encoding the largest subunit of the γTuRC in Arabidopsis thaliana Both mutants showed similar phenotypes of dwarfed vegetative growth and reduced fertility. The gcp6 mutant assembled the γTuSC, while the wild-type cells had GCP6 join other GCPs to produce the γTuRC. Although the gcp6 cells had greatly diminished γ-tubulin localization on spindle MTs, the protein was still detected there. The gcp6 cells formed spindles that lacked MT convergence and discernable poles; however, they managed to cope with the challenge of MT disorganization and were able to complete mitosis and cytokinesis. Our results reveal that the γTuRC is not the only functional form of the γ-tubulin complex for MT nucleation in plant cells, and that γ-tubulin-dependent, but γTuRC-independent, mechanisms meet the basal need of MT nucleation. Moreover, we show that the γTuRC function is more critical for the assembly of spindle MT array than for the phragmoplast. Thus, our findings provide insight into acentrosomal MT nucleation and organization.
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31
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Mitani T, Punetha J, Akalin I, Pehlivan D, Dawidziuk M, Coban Akdemir Z, Yilmaz S, Aslan E, Hunter JV, Hijazi H, Grochowski CM, Jhangiani SN, Karaca E, Fatih JM, Iwanowski P, Gambin T, Wlasienko P, Goszczanska-Ciuchta A, Bekiesinska-Figatowska M, Hosseini M, Arzhangi S, Najmabadi H, Rosenfeld JA, Du H, Marafi D, Blaser S, Teitelbaum R, Silver R, Posey JE, Ropers HH, Gibbs RA, Wiszniewski W, Lupski JR, Chitayat D, Kahrizi K, Gawlinski P, Gawlinski P. Bi-allelic Pathogenic Variants in TUBGCP2 Cause Microcephaly and Lissencephaly Spectrum Disorders. Am J Hum Genet 2019; 105:1005-1015. [PMID: 31630790 DOI: 10.1016/j.ajhg.2019.09.017] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2019] [Accepted: 09/13/2019] [Indexed: 10/25/2022] Open
Abstract
Lissencephaly comprises a spectrum of malformations of cortical development. This spectrum includes agyria, pachygyria, and subcortical band heterotopia; each represents anatomical malformations of brain cortical development caused by neuronal migration defects. The molecular etiologies of neuronal migration anomalies are highly enriched for genes encoding microtubules and microtubule-associated proteins, and this enrichment highlights the critical role for these genes in cortical growth and gyrification. Using exome sequencing and family based rare variant analyses, we identified a homozygous variant (c.997C>T [p.Arg333Cys]) in TUBGCP2, encoding gamma-tubulin complex protein 2 (GCP2), in two individuals from a consanguineous family; both individuals presented with microcephaly and developmental delay. GCP2 forms the multiprotein γ-tubulin ring complex (γ-TuRC) together with γ-tubulin and other GCPs to regulate the assembly of microtubules. By querying clinical exome sequencing cases and through GeneMatcher-facilitated collaborations, we found three additional families with bi-allelic variation and similarly affected phenotypes including a homozygous variant (c.1843G>C [p.Ala615Pro]) in two families and compound heterozygous variants consisting of one missense variant (c.889C>T [p.Arg297Cys]) and one splice variant (c.2025-2A>G) in another family. Brain imaging from all five affected individuals revealed varying degrees of cortical malformations including pachygyria and subcortical band heterotopia, presumably caused by disruption of neuronal migration. Our data demonstrate that pathogenic variants in TUBGCP2 cause an autosomal recessive neurodevelopmental trait consisting of a neuronal migration disorder, and our data implicate GCP2 as a core component of γ-TuRC in neuronal migrating cells.
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Affiliation(s)
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | - Pawel Gawlinski
- Department of Medical Genetics, Institute of Mother and Child, Warsaw, 01-211, Poland.
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32
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O V SS, Palaparthi S, Pidaparti R. Mimicking Sub-Structures Self-Organization in Microtubules. Biomimetics (Basel) 2019; 4:biomimetics4040071. [PMID: 31635308 PMCID: PMC6963431 DOI: 10.3390/biomimetics4040071] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2019] [Revised: 09/19/2019] [Accepted: 10/15/2019] [Indexed: 01/25/2023] Open
Abstract
Microtubules (MTs) are highly dynamic polymers distributed in the cytoplasm of a biological cell. Alpha and beta globular proteins constituting the heterodimer building blocks combine to form these tubules through polymerization, controlled by the concentration of Guanosine-triphosphate (GTPs) and other Microtubule Associated Proteins (MAPs). MTs play a crucial role in many intracellular processes, predominantly in mitosis, organelle transport and cell locomotion. Current research in this area is focused on understanding the exclusive behaviors of self-organization and their association with different MAPs through organized laboratory experiments. However, the intriguing intelligence behind these tiny machines resulting in complex self-organizing structures is mostly unexplored. In this study, we propose a novel swarm engineering framework in modeling rules for these systems, by combining the principles of design with swarm intelligence. The proposed framework was simulated on a game engine and these simulations demonstrated self-organization of rings and protofilaments in MTs. Analytics from these simulations assisted in understanding the influence of GTPs on protofilament formation. Also, results showed that the population density of GTPs rather than their bonding probabilities played a crucial role in polymerization in forming microtubule substructures.
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Affiliation(s)
- Sanjay Sarma O V
- College of Engineering, University of Georgia, Athens, GA 30602, USA.
| | - Sruthi Palaparthi
- Department of Computer Science, University of Georgia, Athens, GA 30602, USA.
| | - Ramana Pidaparti
- College of Engineering, University of Georgia, Athens, GA 30602, USA.
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33
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Yamada M, Hayashi K. Microtubule nucleation in the cytoplasm of developing cortical neurons and its regulation by brain‐derived neurotrophic factor. Cytoskeleton (Hoboken) 2019; 76:339-345. [DOI: 10.1002/cm.21550] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2019] [Revised: 06/25/2019] [Accepted: 06/27/2019] [Indexed: 01/06/2023]
Affiliation(s)
- Mimori Yamada
- Department of Materials and Life SciencesFaculty of Science and Technology, Sophia University Tokyo Japan
| | - Kensuke Hayashi
- Department of Materials and Life SciencesFaculty of Science and Technology, Sophia University Tokyo Japan
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34
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Joukov V, De Nicolo A. The Centrosome and the Primary Cilium: The Yin and Yang of a Hybrid Organelle. Cells 2019; 8:E701. [PMID: 31295970 PMCID: PMC6678760 DOI: 10.3390/cells8070701] [Citation(s) in RCA: 63] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2019] [Revised: 07/04/2019] [Accepted: 07/06/2019] [Indexed: 12/27/2022] Open
Abstract
Centrosomes and primary cilia are usually considered as distinct organelles, although both are assembled with the same evolutionary conserved, microtubule-based templates, the centrioles. Centrosomes serve as major microtubule- and actin cytoskeleton-organizing centers and are involved in a variety of intracellular processes, whereas primary cilia receive and transduce environmental signals to elicit cellular and organismal responses. Understanding the functional relationship between centrosomes and primary cilia is important because defects in both structures have been implicated in various diseases, including cancer. Here, we discuss evidence that the animal centrosome evolved, with the transition to complex multicellularity, as a hybrid organelle comprised of the two distinct, but intertwined, structural-functional modules: the centriole/primary cilium module and the pericentriolar material/centrosome module. The evolution of the former module may have been caused by the expanding cellular diversification and intercommunication, whereas that of the latter module may have been driven by the increasing complexity of mitosis and the requirement for maintaining cell polarity, individuation, and adhesion. Through its unique ability to serve both as a plasma membrane-associated primary cilium organizer and a juxtanuclear microtubule-organizing center, the animal centrosome has become an ideal integrator of extracellular and intracellular signals with the cytoskeleton and a switch between the non-cell autonomous and the cell-autonomous signaling modes. In light of this hypothesis, we discuss centrosome dynamics during cell proliferation, migration, and differentiation and propose a model of centrosome-driven microtubule assembly in mitotic and interphase cells. In addition, we outline the evolutionary benefits of the animal centrosome and highlight the hierarchy and modularity of the centrosome biogenesis networks.
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Affiliation(s)
- Vladimir Joukov
- N.N. Petrov National Medical Research Center of Oncology, 197758 Saint-Petersburg, Russia.
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35
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Mukherjee A, Conduit PT. γ-TuRCs. Curr Biol 2019; 29:R398-R400. [PMID: 31163138 DOI: 10.1016/j.cub.2019.04.013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
Mukherjee and Conduit introduce γ-tubulin ring complexes (γ-TuRCs), multi-protein complexes that catalyse the kinetically unfavourable formation of new microtubules in cells.
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Affiliation(s)
- Amrita Mukherjee
- Department of Zoology, University of Cambridge, Downing Street, Cambridge, CB2 3EJ, UK.
| | - Paul T Conduit
- Department of Zoology, University of Cambridge, Downing Street, Cambridge, CB2 3EJ, UK.
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Lee YRJ, Liu B. Microtubule nucleation for the assembly of acentrosomal microtubule arrays in plant cells. THE NEW PHYTOLOGIST 2019; 222:1705-1718. [PMID: 30681146 DOI: 10.1111/nph.15705] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/03/2018] [Accepted: 01/07/2019] [Indexed: 05/15/2023]
Abstract
Contents Summary I. Introduction II. MT arrays in plant cells III. γ-Tubulin and MT nucleation IV. MT nucleation sites or flexible MTOCs in plant cells V. MT-dependent MT nucleation VI. Generating new MTs for spindle assembly VII. Generation of MTs for phragmoplast expansion during cytokinesis VIII. MT generation for the cortical MT array IX. MT nucleation: looking forward Acknowledgements References SUMMARY: Cytoskeletal microtubules (MTs) have a multitude of functions including intracellular distribution of molecules and organelles, cell morphogenesis, as well as segregation of the genetic material and separation of the cytoplasm during cell division among eukaryotic organisms. In response to internal and external cues, eukaryotic cells remodel their MT network in a regulated manner in order to assemble physiologically important arrays for cell growth, cell proliferation, or for cells to cope with biotic or abiotic stresses. Nucleation of new MTs is a critical step for MT remodeling. Although many key factors contributing to MT nucleation and organization are well conserved in different kingdoms, the centrosome, representing the most prominent microtubule organizing centers (MTOCs), disappeared during plant evolution as angiosperms lack the structure. Instead, flexible MTOCs may emerge on the plasma membrane, the nuclear envelope, and even organelles depending on types of cells and organisms and/or physiological conditions. MT-dependent MT nucleation is particularly noticeable in plant cells because it accounts for the primary source of MT generation for assembling spindle, phragmoplast, and cortical arrays when the γ-tubulin ring complex is anchored and activated by the augmin complex. It is intriguing what proteins are associated with plant-specific MTOCs and how plant cells activate or inactivate MT nucleation activities in spatiotemporally regulated manners.
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Affiliation(s)
- Yuh-Ru Julie Lee
- Department of Plant Biology, University of California, Davis, CA, 95616, USA
| | - Bo Liu
- Department of Plant Biology, University of California, Davis, CA, 95616, USA
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Sreeja JS, Nellikka RK, John R, Sivakumar KC, Sreekumar E, Sengupta S. Binding of alpha-fodrin to gamma-tubulin accounts for its role in the inhibition of microtubule nucleation. FEBS Lett 2019; 593:1154-1165. [PMID: 31062342 DOI: 10.1002/1873-3468.13425] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2019] [Revised: 04/12/2019] [Accepted: 04/18/2019] [Indexed: 11/10/2022]
Abstract
Non-erythroid spectrin or fodrin is present as part of the γ-tubulin ring complex (γ-TuRC) in brain tissue and brain derived cells. Here, we show that fodrin, which is otherwise known for providing structural support to the cell membrane, interacts directly with γ-tubulin within the γ-TuRC through a GRIP2-like motif. Turbidometric analysis of microtubule polymerization with nucleation-potent γ-TuRC isolated from HEK-293 cells that lack fodrin and the γ-TuRC from goat brain that contains fodrin shows inefficiency of the latter to promote nucleation. The involvement of fodrin was confirmed by the reduction in the microtubule polymerization efficiency of HEK-293 derived γ-TuRCs upon addition of purified brain fodrin. Thus, the interaction of fodrin with gamma-tubulin is responsible for its inhibitory effect on γ-tubulin mediated microtubule nucleation.
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Affiliation(s)
- Jamuna S Sreeja
- Cancer Research Programme, Rajiv Gandhi Centre for Biotechnology, Trivandrum, India
| | | | - Rince John
- Cancer Research Programme, Rajiv Gandhi Centre for Biotechnology, Trivandrum, India
| | | | - Easwaran Sreekumar
- Viral Disease Biology, Rajiv Gandhi Centre for Biotechnology, Trivandrum, India
| | - Suparna Sengupta
- Cancer Research Programme, Rajiv Gandhi Centre for Biotechnology, Trivandrum, India
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Regulation of Microtubule Nucleation in Mouse Bone Marrow-Derived Mast Cells by Protein Tyrosine Phosphatase SHP-1. Cells 2019; 8:cells8040345. [PMID: 30979083 PMCID: PMC6523986 DOI: 10.3390/cells8040345] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2019] [Revised: 03/30/2019] [Accepted: 04/10/2019] [Indexed: 12/20/2022] Open
Abstract
The antigen-mediated activation of mast cells initiates signaling events leading to their degranulation, to the release of inflammatory mediators, and to the synthesis of cytokines and chemokines. Although rapid and transient microtubule reorganization during activation has been described, the molecular mechanisms that control their rearrangement are largely unknown. Microtubule nucleation is mediated by γ-tubulin complexes. In this study, we report on the regulation of microtubule nucleation in bone marrow-derived mast cells (BMMCs) by Src homology 2 (SH2) domain-containing protein tyrosine phosphatase 1 (SHP-1; Ptpn6). Reciprocal immunoprecipitation experiments and pull-down assays revealed that SHP-1 is present in complexes containing γ-tubulin complex proteins and protein tyrosine kinase Syk. Microtubule regrowth experiments in cells with deleted SHP-1 showed a stimulation of microtubule nucleation, and phenotypic rescue experiments confirmed that SHP-1 represents a negative regulator of microtubule nucleation in BMMCs. Moreover, the inhibition of the SHP-1 activity by inhibitors TPI-1 and NSC87877 also augmented microtubule nucleation. The regulation was due to changes in γ-tubulin accumulation. Further experiments with antigen-activated cells showed that the deletion of SHP-1 stimulated the generation of microtubule protrusions, the activity of Syk kinase, and degranulation. Our data suggest a novel mechanism for the suppression of microtubule formation in the later stages of mast cell activation.
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Abstract
Microtubules are major constituents of the cytoskeleton in all eukaryotic cells. They are essential for chromosome segregation during cell division, for directional intracellular transport and for building specialized cellular structures such as cilia or flagella. Their assembly has to be controlled spatially and temporally. For this, the cell uses multiprotein complexes containing γ-tubulin. γ-Tubulin has been found in two different types of complexes, γ-tubulin small complexes and γ-tubulin ring complexes. Binding to adaptors and activator proteins transforms these complexes into structural templates that drive the nucleation of new microtubules in a highly controlled manner. This review discusses recent advances on the mechanisms of assembly, recruitment and activation of γ-tubulin complexes at microtubule-organizing centres.
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Affiliation(s)
- Dorian Farache
- Centre de Biologie Intégrative, Centre de Biologie du Développement, CNRS-Université Toulouse III, 31062 Toulouse, France
| | - Laurent Emorine
- Centre de Biologie Intégrative, Centre de Biologie du Développement, CNRS-Université Toulouse III, 31062 Toulouse, France
| | - Laurence Haren
- Centre de Biologie Intégrative, Centre de Biologie du Développement, CNRS-Université Toulouse III, 31062 Toulouse, France
| | - Andreas Merdes
- Centre de Biologie Intégrative, Centre de Biologie du Développement, CNRS-Université Toulouse III, 31062 Toulouse, France
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40
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Dwivedi D, Kumari A, Rathi S, Mylavarapu SVS, Sharma M. The dynein adaptor Hook2 plays essential roles in mitotic progression and cytokinesis. J Cell Biol 2019; 218:871-894. [PMID: 30674580 PMCID: PMC6400558 DOI: 10.1083/jcb.201804183] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2018] [Revised: 10/29/2018] [Accepted: 12/07/2018] [Indexed: 12/16/2022] Open
Abstract
Hook proteins are evolutionarily conserved dynein adaptors that promote assembly of highly processive dynein-dynactin motor complexes. Mammals express three Hook paralogs, namely Hook1, Hook2, and Hook3, that have distinct subcellular localizations and expectedly, distinct cellular functions. Here we demonstrate that Hook2 binds to and promotes dynein-dynactin assembly specifically during mitosis. During the late G2 phase, Hook2 mediates dynein-dynactin localization at the nuclear envelope (NE), which is required for centrosome anchoring to the NE. Independent of its binding to dynein, Hook2 regulates microtubule nucleation at the centrosome; accordingly, Hook2-depleted cells have reduced astral microtubules and spindle positioning defects. Besides the centrosome, Hook2 localizes to and recruits dynactin and dynein to the central spindle. Dynactin-dependent targeting of centralspindlin complex to the midzone is abrogated upon Hook2 depletion; accordingly, Hook2 depletion results in cytokinesis failure. We find that the zebrafish Hook2 homologue promotes dynein-dynactin association and was essential for zebrafish early development. Together, these results suggest that Hook2 mediates assembly of the dynein-dynactin complex and regulates mitotic progression and cytokinesis.
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Affiliation(s)
- Devashish Dwivedi
- Department of Biological Sciences, Indian Institute of Science Education and Research, Mohali, India
| | - Amrita Kumari
- Laboratory of Cellular Dynamics, Regional Centre for Biotechnology, Faridabad, India.,Affiliated to Manipal Academy of Higher Education, Manipal, India
| | - Siddhi Rathi
- Department of Biological Sciences, Indian Institute of Science Education and Research, Mohali, India
| | - Sivaram V S Mylavarapu
- Laboratory of Cellular Dynamics, Regional Centre for Biotechnology, Faridabad, India.,Affiliated to Manipal Academy of Higher Education, Manipal, India
| | - Mahak Sharma
- Department of Biological Sciences, Indian Institute of Science Education and Research, Mohali, India
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41
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Abstract
Neurons are polarized cells with long branched axons and dendrites. Microtubule generation and organization machineries are crucial to grow and pattern these complex cellular extensions. Microtubule organizing centers (MTOCs) concentrate the molecular machinery for templating microtubules, stabilizing the nascent polymer, and organizing the resultant microtubules into higher-order structures. MTOC formation and function are well described at the centrosome, in the spindle, and at interphase Golgi; we review these studies and then describe recent results about how the machineries acting at these classic MTOCs are repurposed in the postmitotic neuron for axon and dendrite differentiation. We further discuss a constant tug-of-war interplay between different MTOC activities in the cell and how this process can be used as a substrate for transcription factor-mediated diversification of neuron types.
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Affiliation(s)
- Jason Y Tann
- Laboratory for Neurodiversity, RIKEN Centre for Brain Science, Saitama, Japan
| | - Adrian W Moore
- Laboratory for Neurodiversity, RIKEN Centre for Brain Science, Saitama, Japan.
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42
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Roman AC, Garrido-Jimenez S, Diaz-Chamorro S, Centeno F, Carvajal-Gonzalez JM. Centriole Positioning: Not Just a Little Dot in the Cell. Results Probl Cell Differ 2019; 67:201-221. [PMID: 31435796 DOI: 10.1007/978-3-030-23173-6_8] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
Organelle positioning as many other morphological parameters in a cell is not random. Centriole positioning as centrosomes or ciliary basal bodies is not an exception to this rule in cell biology. Indeed, centriole positioning is a tightly regulated process that occurs during development, and it is critical for many organs to function properly, not just during development but also in the adulthood. In this book chapter, we overview our knowledge on centriole positioning in different and highly specialized animal cells like photoreceptor or ependymal cells. We will also discuss recent advances in the discovery of molecular pathways involved in this process, mostly related to the cytoskeleton and the cell polarity pathways. And finally, we present quantitative methods that have been used to assess centriole positioning in different cell types although mostly in epithelial cells.
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Affiliation(s)
- Angel-Carlos Roman
- Facultad de Ciencias, Departamento de Bioquímica, Biología Molecular y Genética, Universidad de Extremadura, Badajoz, Spain
| | - Sergio Garrido-Jimenez
- Facultad de Ciencias, Departamento de Bioquímica, Biología Molecular y Genética, Universidad de Extremadura, Badajoz, Spain
| | - Selene Diaz-Chamorro
- Facultad de Ciencias, Departamento de Bioquímica, Biología Molecular y Genética, Universidad de Extremadura, Badajoz, Spain
| | - Francisco Centeno
- Facultad de Ciencias, Departamento de Bioquímica, Biología Molecular y Genética, Universidad de Extremadura, Badajoz, Spain
| | - Jose Maria Carvajal-Gonzalez
- Facultad de Ciencias, Departamento de Bioquímica, Biología Molecular y Genética, Universidad de Extremadura, Badajoz, Spain.
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43
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Microtubule nucleation by γ-tubulin complexes and beyond. Essays Biochem 2018; 62:765-780. [PMID: 30315097 PMCID: PMC6281477 DOI: 10.1042/ebc20180028] [Citation(s) in RCA: 75] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2018] [Revised: 09/05/2018] [Accepted: 09/13/2018] [Indexed: 12/21/2022]
Abstract
In this short review, we give an overview of microtubule nucleation within cells. It is nearly 30 years since the discovery of γ-tubulin, a member of the tubulin superfamily essential for proper microtubule nucleation in all eukaryotes. γ-tubulin associates with other proteins to form multiprotein γ-tubulin ring complexes (γ-TuRCs) that template and catalyse the otherwise kinetically unfavourable assembly of microtubule filaments. These filaments can be dynamic or stable and they perform diverse functions, such as chromosome separation during mitosis and intracellular transport in neurons. The field has come a long way in understanding γ-TuRC biology but several important and unanswered questions remain, and we are still far from understanding the regulation of microtubule nucleation in a multicellular context. Here, we review the current literature on γ-TuRC assembly, recruitment, and activation and discuss the potential importance of γ-TuRC heterogeneity, the role of non-γ-TuRC proteins in microtubule nucleation, and whether γ-TuRCs could serve as good drug targets for cancer therapy.
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44
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Montenegro Gouveia S, Zitouni S, Kong D, Duarte P, Ferreira Gomes B, Sousa AL, Tranfield EM, Hyman A, Loncarek J, Bettencourt-Dias M. PLK4 is a microtubule-associated protein that self-assembles promoting de novo MTOC formation. J Cell Sci 2018; 132:jcs.219501. [PMID: 30237222 PMCID: PMC6398482 DOI: 10.1242/jcs.219501] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2018] [Accepted: 09/10/2018] [Indexed: 01/09/2023] Open
Abstract
The centrosome is an important microtubule-organising centre (MTOC) in animal cells. It consists of two barrel-shaped structures, the centrioles, surrounded by the pericentriolar material (PCM), which nucleates microtubules. Centrosomes can form close to an existing structure (canonical duplication) or de novo. How centrosomes form de novo is not known. The master driver of centrosome biogenesis, PLK4, is critical for the recruitment of several centriole components. Here, we investigate the beginning of centrosome biogenesis, taking advantage of Xenopus egg extracts, where PLK4 can induce de novo MTOC formation (
Eckerdt et al., 2011; Zitouni et al., 2016). Surprisingly, we observe that in vitro, PLK4 can self-assemble into condensates that recruit α- and β-tubulins. In Xenopus extracts, PLK4 assemblies additionally recruit STIL, a substrate of PLK4, and the microtubule nucleator γ-tubulin, forming acentriolar MTOCs de novo. The assembly of these robust microtubule asters is independent of dynein, similar to what is found for centrosomes. We suggest a new mechanism of action for PLK4, where it forms a self-organising catalytic scaffold that recruits centriole components, PCM factors and α- and β-tubulins, leading to MTOC formation. This article has an associated First Person interview with the first author of the paper. Summary: PLK4 binds to microtubules and self-assembles into condensates that recruit tubulin and trigger de novo microtubule-organising centre formation in vitro.
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Affiliation(s)
- Susana Montenegro Gouveia
- Cell Cycle Regulation Laboratory, Instituto Gulbenkian de Ciência, Rua da Quinta Grande 6, Oeiras, 2780-156, Portugal
| | - Sihem Zitouni
- Cell Cycle Regulation Laboratory, Instituto Gulbenkian de Ciência, Rua da Quinta Grande 6, Oeiras, 2780-156, Portugal
| | - Dong Kong
- Laboratory of Protein Dynamics and Signalling, National Institutes of Health/National Cancer Institute/Center for Cancer Research, Frederick, MD 21702, USA
| | - Paulo Duarte
- Cell Cycle Regulation Laboratory, Instituto Gulbenkian de Ciência, Rua da Quinta Grande 6, Oeiras, 2780-156, Portugal
| | - Beatriz Ferreira Gomes
- Max Planck Institute of Molecular Biology and Genetics, Pfotenhauerstrasse 108, 01307 Dresden, Germany
| | - Ana Laura Sousa
- Cell Cycle Regulation Laboratory, Instituto Gulbenkian de Ciência, Rua da Quinta Grande 6, Oeiras, 2780-156, Portugal
| | - Erin M Tranfield
- Cell Cycle Regulation Laboratory, Instituto Gulbenkian de Ciência, Rua da Quinta Grande 6, Oeiras, 2780-156, Portugal
| | - Anthony Hyman
- Max Planck Institute of Molecular Biology and Genetics, Pfotenhauerstrasse 108, 01307 Dresden, Germany
| | - Jadranka Loncarek
- Laboratory of Protein Dynamics and Signalling, National Institutes of Health/National Cancer Institute/Center for Cancer Research, Frederick, MD 21702, USA
| | - Monica Bettencourt-Dias
- Cell Cycle Regulation Laboratory, Instituto Gulbenkian de Ciência, Rua da Quinta Grande 6, Oeiras, 2780-156, Portugal
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45
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LaFlamme SE, Mathew-Steiner S, Singh N, Colello-Borges D, Nieves B. Integrin and microtubule crosstalk in the regulation of cellular processes. Cell Mol Life Sci 2018; 75:4177-4185. [PMID: 30206641 PMCID: PMC6182340 DOI: 10.1007/s00018-018-2913-x] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2018] [Revised: 08/14/2018] [Accepted: 08/27/2018] [Indexed: 11/25/2022]
Abstract
Integrins engage components of the extracellular matrix, and in collaboration with other receptors, regulate signaling cascades that impact cell behavior in part by modulating the cell's cytoskeleton. Integrins have long been known to function together with the actin cytoskeleton to promote cell adhesion, migration, and invasion, and with the intermediate filament cytoskeleton to mediate the strong adhesion needed for the maintenance and integrity of epithelial tissues. Recent studies have shed light on the crosstalk between integrin and the microtubule cytoskeleton. Integrins promote microtubule nucleation, growth, and stabilization at the cell cortex, whereas microtubules regulate integrin activity and remodeling of adhesion sites. Integrin-dependent stabilization of microtubules at the cell cortex is critical to the establishment of apical-basal polarity required for the formation of epithelial tissues. During cell migration, integrin-dependent microtubule stabilization contributes to front-rear polarity, whereas microtubules promote the turnover of integrin-mediated adhesions. This review focuses on this interdependent relationship and its impact on cell behavior and function.
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Affiliation(s)
- Susan E LaFlamme
- Department of Regenerative and Cancer Cell Biology, Albany Medical College, 47 New Scotland Avenue, Albany, NY, 12208, USA.
| | - Shomita Mathew-Steiner
- Department of Regenerative and Cancer Cell Biology, Albany Medical College, 47 New Scotland Avenue, Albany, NY, 12208, USA
- Indiana University, 975 W. Walnut Street, Indianapolis, IN, 46202, USA
| | - Neetu Singh
- Department of Regenerative and Cancer Cell Biology, Albany Medical College, 47 New Scotland Avenue, Albany, NY, 12208, USA
| | - Diane Colello-Borges
- Department of Regenerative and Cancer Cell Biology, Albany Medical College, 47 New Scotland Avenue, Albany, NY, 12208, USA
| | - Bethsaida Nieves
- Department of Regenerative and Cancer Cell Biology, Albany Medical College, 47 New Scotland Avenue, Albany, NY, 12208, USA
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46
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Romé P, Ohkura H. A novel microtubule nucleation pathway for meiotic spindle assembly in oocytes. J Cell Biol 2018; 217:3431-3445. [PMID: 30087124 PMCID: PMC6168254 DOI: 10.1083/jcb.201803172] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2018] [Revised: 04/10/2018] [Accepted: 07/18/2018] [Indexed: 12/25/2022] Open
Abstract
The meiotic spindle in oocytes is assembled in the absence of centrosomes, the major microtubule nucleation sites in mitotic and male meiotic cells. A crucial, yet unresolved question in meiosis is how spindle microtubules are generated without centrosomes and only around chromosomes in the exceptionally large volume of oocytes. Here we report a novel oocyte-specific microtubule nucleation pathway that is essential for assembling most spindle microtubules complementarily with the Augmin pathway. This pathway is mediated by the kinesin-6 Subito/MKlp2, which recruits the γ-tubulin complex to the spindle equator to nucleate microtubules in Drosophila oocytes. Away from chromosomes, Subito interaction with the γ-tubulin complex is suppressed by its N-terminal region to prevent ectopic microtubule assembly in oocytes. We further demonstrate in vitro that the Subito complex from ovaries can nucleate microtubules from pure tubulin dimers. Collectively, microtubule nucleation regulated by Subito drives spatially restricted spindle assembly in oocytes.
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Affiliation(s)
- Pierre Romé
- Wellcome Centre for Cell Biology, School of Biological Sciences, University of Edinburgh, Scotland, UK
| | - Hiroyuki Ohkura
- Wellcome Centre for Cell Biology, School of Biological Sciences, University of Edinburgh, Scotland, UK
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47
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Gavilan MP, Gandolfo P, Balestra FR, Arias F, Bornens M, Rios RM. The dual role of the centrosome in organizing the microtubule network in interphase. EMBO Rep 2018; 19:embr.201845942. [PMID: 30224411 DOI: 10.15252/embr.201845942] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2018] [Revised: 08/27/2018] [Accepted: 08/29/2018] [Indexed: 11/09/2022] Open
Abstract
Here, we address the regulation of microtubule nucleation during interphase by genetically ablating one, or two, of three major mammalian γ-TuRC-binding factors namely pericentrin, CDK5Rap2, and AKAP450. Unexpectedly, we find that while all of them participate in microtubule nucleation at the Golgi apparatus, they only modestly contribute at the centrosome where CEP192 has a more predominant function. We also show that inhibiting microtubule nucleation at the Golgi does not affect centrosomal activity, whereas manipulating the number of centrosomes with centrinone modifies microtubule nucleation activity of the Golgi apparatus. In centrosome-free cells, inhibition of Golgi-based microtubule nucleation triggers pericentrin-dependent formation of cytoplasmic-nucleating structures. Further depletion of pericentrin under these conditions leads to the generation of individual microtubules in a γ-tubulin-dependent manner. In all cases, a conspicuous MT network forms. Strikingly, centrosome loss increases microtubule number independently of where they were growing from. Our results lead to an unexpected view of the interphase centrosome that would control microtubule network organization not only by nucleating microtubules, but also by modulating the activity of alternative microtubule-organizing centers.
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Affiliation(s)
- Maria P Gavilan
- Centro Andaluz de Biología Molecular y Medicina Regenerativa CABIMER, Universidad de Sevilla-CSIC-Universidad Pablo de Olavide, Seville, Spain
| | - Pablo Gandolfo
- Centro Andaluz de Biología Molecular y Medicina Regenerativa CABIMER, Universidad de Sevilla-CSIC-Universidad Pablo de Olavide, Seville, Spain
| | - Fernando R Balestra
- Centro Andaluz de Biología Molecular y Medicina Regenerativa CABIMER, Universidad de Sevilla-CSIC-Universidad Pablo de Olavide, Seville, Spain
| | - Francisco Arias
- Centro Andaluz de Biología Molecular y Medicina Regenerativa CABIMER, Universidad de Sevilla-CSIC-Universidad Pablo de Olavide, Seville, Spain
| | | | - Rosa M Rios
- Centro Andaluz de Biología Molecular y Medicina Regenerativa CABIMER, Universidad de Sevilla-CSIC-Universidad Pablo de Olavide, Seville, Spain
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48
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Kume K, Kaneko S, Nishikawa K, Mizunuma M, Hirata D. Role of nucleocytoplasmic transport in interphase microtubule organization in fission yeast. Biochem Biophys Res Commun 2018; 503:1160-1167. [PMID: 29958883 DOI: 10.1016/j.bbrc.2018.06.135] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2018] [Accepted: 06/24/2018] [Indexed: 11/25/2022]
Abstract
The proper organization of microtubules is essential for many cellular functions. Microtubule organization and reorganization are highly regulated during the cell cycle, but the underlying mechanisms remain elusive. Here we characterized unusual interphase microtubule organization in fission yeast nuclear export mutant crm1-124. The mutant cells have an intranuclear microtubule bundle during interphase that pushes the nuclear envelope to assume a protruding morphology. We showed that the formation of this protruding microtubule bundle requires the nuclear accumulation of two microtubule-associated proteins (MAPs), Alp14/TOG and Mal3/EB1. Interestingly, the forced accumulation of Alp14 in the nucleus of wild type cells is sufficient to form the intranuclear microtubule bundle. Furthermore, the frequency of the intranuclear microtubule formation by Alp14 accumulated in the nucleus is prominently increased by a reduction in the nucleation activity of interphase cytoplasmic microtubules. We propose that properly regulated nucleocytoplasmic transport and maintained activity of cytoplasmic microtubule nucleation during interphase are important for the proper organization of interphase cytoplasmic microtubules.
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Affiliation(s)
- Kazunori Kume
- Hiroshima Research Center for Healthy Aging, Department of Molecular Biotechnology, Graduate School of Advanced Sciences of Matter, Hiroshima University, 1-3-1 Kagamiyama, Higashi-Hiroshima, 739-8530, Japan.
| | - Sayuri Kaneko
- Hiroshima Research Center for Healthy Aging, Department of Molecular Biotechnology, Graduate School of Advanced Sciences of Matter, Hiroshima University, 1-3-1 Kagamiyama, Higashi-Hiroshima, 739-8530, Japan
| | - Kenji Nishikawa
- Hiroshima Research Center for Healthy Aging, Department of Molecular Biotechnology, Graduate School of Advanced Sciences of Matter, Hiroshima University, 1-3-1 Kagamiyama, Higashi-Hiroshima, 739-8530, Japan
| | - Masaki Mizunuma
- Hiroshima Research Center for Healthy Aging, Department of Molecular Biotechnology, Graduate School of Advanced Sciences of Matter, Hiroshima University, 1-3-1 Kagamiyama, Higashi-Hiroshima, 739-8530, Japan
| | - Dai Hirata
- Hiroshima Research Center for Healthy Aging, Department of Molecular Biotechnology, Graduate School of Advanced Sciences of Matter, Hiroshima University, 1-3-1 Kagamiyama, Higashi-Hiroshima, 739-8530, Japan; Asahi-Shuzo Sake Brewing Co., Ltd., 880-1 Asahi, Nagaoka, 949-5494, Japan
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49
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Tovey CA, Tubman CE, Hamrud E, Zhu Z, Dyas AE, Butterfield AN, Fyfe A, Johnson E, Conduit PT. γ-TuRC Heterogeneity Revealed by Analysis of Mozart1. Curr Biol 2018; 28:2314-2323.e6. [PMID: 29983314 PMCID: PMC6065531 DOI: 10.1016/j.cub.2018.05.044] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2017] [Revised: 04/06/2018] [Accepted: 05/16/2018] [Indexed: 12/13/2022]
Abstract
Microtubules are essential for various cell processes [1] and are nucleated by multi-protein γ-tubulin ring complexes (γ-TuRCs) at various microtubule organizing centers (MTOCs), including centrosomes [2-6]. Recruitment of γ-TuRCs to different MTOCs at different times influences microtubule array formation, but how this is regulated remains an open question. It also remains unclear whether all γ-TuRCs within the same organism have the same composition and how any potential heterogeneity might influence γ-TuRC recruitment. MOZART1 (Mzt1) was recently identified as a γ-TuRC component [7, 8] and is conserved in nearly all eukaryotes [6, 9]. Mzt1 has so far been studied in cultured human cells, yeast, and plants; its absence leads to failures in γ-TuRC recruitment and cell division, resulting in cell death [7, 9-15]. Mzt1 is small (∼8.5 kDa), binds directly to core γ-TuRC components [9, 10, 14, 15], and appears to mediate the interaction between γ-TuRCs and proteins that tether γ-TuRCs to MTOCs [9, 15]. Here, we use Drosophila to investigate the function of Mzt1 in a multicellular animal for the first time. Surprisingly, we find that Drosophila Mzt1 is expressed only in the testes and is present in γ-TuRCs recruited to basal bodies, but not to mitochondria, in developing sperm cells. mzt1 mutants are viable but have defects in basal body positioning and γ-TuRC recruitment to centriole adjuncts; sperm formation is affected and mutants display a rapid age-dependent decline in sperm motility and male fertility. Our results reveal that tissue-specific and MTOC-specific γ-TuRC heterogeneity exist in Drosophila and highlight the complexity of γ-TuRC recruitment in a multicellular animal.
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Affiliation(s)
- Corinne A Tovey
- Department of Zoology, University of Cambridge, Downing Street, Cambridge CB2 3EJ, UK
| | - Chloe E Tubman
- Department of Zoology, University of Cambridge, Downing Street, Cambridge CB2 3EJ, UK
| | - Eva Hamrud
- Department of Zoology, University of Cambridge, Downing Street, Cambridge CB2 3EJ, UK
| | - Zihan Zhu
- Department of Zoology, University of Cambridge, Downing Street, Cambridge CB2 3EJ, UK
| | - Anna E Dyas
- Department of Zoology, University of Cambridge, Downing Street, Cambridge CB2 3EJ, UK
| | - Andrew N Butterfield
- Department of Zoology, University of Cambridge, Downing Street, Cambridge CB2 3EJ, UK
| | - Alex Fyfe
- Sir William Dunn School of Pathology, University of Oxford, South Parks Road, Oxford OX1 3RE, UK
| | - Errin Johnson
- Sir William Dunn School of Pathology, University of Oxford, South Parks Road, Oxford OX1 3RE, UK
| | - Paul T Conduit
- Department of Zoology, University of Cambridge, Downing Street, Cambridge CB2 3EJ, UK.
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Ito D, Bettencourt-Dias M. Centrosome Remodelling in Evolution. Cells 2018; 7:E71. [PMID: 29986477 PMCID: PMC6070874 DOI: 10.3390/cells7070071] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2018] [Revised: 06/27/2018] [Accepted: 07/04/2018] [Indexed: 11/16/2022] Open
Abstract
The centrosome is the major microtubule organizing centre (MTOC) in animal cells. The canonical centrosome is composed of two centrioles surrounded by a pericentriolar matrix (PCM). In contrast, yeasts and amoebozoa have lost centrioles and possess acentriolar centrosomes—called the spindle pole body (SPB) and the nucleus-associated body (NAB), respectively. Despite the difference in their structures, centriolar centrosomes and SPBs not only share components but also common biogenesis regulators. In this review, we focus on the SPB and speculate how its structures evolved from the ancestral centrosome. Phylogenetic distribution of molecular components suggests that yeasts gained specific SPB components upon loss of centrioles but maintained PCM components associated with the structure. It is possible that the PCM structure remained even after centrosome remodelling due to its indispensable function to nucleate microtubules. We propose that the yeast SPB has been formed by a step-wise process; (1) an SPB-like precursor structure appeared on the ancestral centriolar centrosome; (2) it interacted with the PCM and the nuclear envelope; and (3) it replaced the roles of centrioles. Acentriolar centrosomes should continue to be a great model to understand how centrosomes evolved and how centrosome biogenesis is regulated.
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Affiliation(s)
- Daisuke Ito
- Instituto Gulbenkian de Ciência, Rua da Quinta Grande 6, 2780-156 Oeiras, Portugal.
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