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Sun S, Zhou J, Liu P. Liquid-liquid phase separation of microtubule-binding proteins in the regulation of spindle assembly. Cell Prolif 2024:e13649. [PMID: 38736355 DOI: 10.1111/cpr.13649] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2023] [Revised: 03/19/2024] [Accepted: 04/15/2024] [Indexed: 05/14/2024] Open
Abstract
Cell division is a highly regulated process essential for the accurate segregation of chromosomes. Central to this process is the assembly of a bipolar mitotic spindle, a highly dynamic microtubule (MT)-based structure responsible for chromosome movement. The nucleation and dynamics of MTs are intricately regulated by MT-binding proteins. Over the recent years, various MT-binding proteins have been reported to undergo liquid-liquid phase separation, forming either single- or multi-component condensates on MTs. Herein, we provide a comprehensive summary of the phase separation characteristics of these proteins. We underscore their critical roles in MT nucleation, spindle assembly and kinetochore-MT attachment during the cell division process. Furthermore, we discuss the current challenges and various remaining unsolved problems, highlights the ongoing research efforts aimed at a deeper understanding of the role of the phase separation process during spindle assembly and orientation. Our review aims to contribute to the collective knowledge in this area and stimulate further investigations that will enhance our comprehension of the intricate mechanisms governing cell division.
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Affiliation(s)
- Shuang Sun
- Center for Cell Structure and Function, Shandong Provincial Key Laboratory of Animal Resistance Biology, Collaborative Innovation Center of Cell Biology in Universities of Shandong, Institute of Biomedical Sciences, College of Life Sciences, Shandong Normal University, Jinan, China
| | - Jun Zhou
- Center for Cell Structure and Function, Shandong Provincial Key Laboratory of Animal Resistance Biology, Collaborative Innovation Center of Cell Biology in Universities of Shandong, Institute of Biomedical Sciences, College of Life Sciences, Shandong Normal University, Jinan, China
- State Key Laboratory of Medicinal Chemical Biology, Haihe Laboratory of Cell Ecosystem, College of Life Sciences, Nankai University, Tianjin, China
| | - Peiwei Liu
- Center for Cell Structure and Function, Shandong Provincial Key Laboratory of Animal Resistance Biology, Collaborative Innovation Center of Cell Biology in Universities of Shandong, Institute of Biomedical Sciences, College of Life Sciences, Shandong Normal University, Jinan, China
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2
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Deshpande O, Telley IA. Nuclear positioning during development: Pushing, pulling and flowing. Semin Cell Dev Biol 2021; 120:10-21. [PMID: 34642103 DOI: 10.1016/j.semcdb.2021.09.020] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2021] [Revised: 09/29/2021] [Accepted: 09/30/2021] [Indexed: 01/13/2023]
Abstract
The positioning of the nucleus, the central organelle of the cell, is an active and regulated process crucially linked to cell cycle, differentiation, migration, and polarity. Alterations in positioning have been correlated with cell and tissue function deficiency and genetic or chemical manipulation of nuclear position is embryonic lethal. Nuclear positioning is a precursor for symmetric or asymmetric cell division which is accompanied by fate determination of the daughter cells. Nuclear positioning also plays a key role during early embryonic developmental stages in insects, such as Drosophila, where hundreds of nuclei divide without cytokinesis and are distributed within the large syncytial embryo at roughly regular spacing. While the cytoskeletal elements and the linker proteins to the nucleus are fairly well characterised, including some of the force generating elements driving nuclear movement, there is considerable uncertainty about the biophysical mechanism of nuclear positioning, while the field is debating different force models. In this review, we highlight the current body of knowledge, discuss cell context dependent models of nuclear positioning, and outline open questions.
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Affiliation(s)
- Ojas Deshpande
- Instituto Gulbenkian de Ciência (IGC), Rua da Quinta Grande 6, 2780-156 Oeiras, Portugal
| | - Ivo A Telley
- Instituto Gulbenkian de Ciência (IGC), Rua da Quinta Grande 6, 2780-156 Oeiras, Portugal.
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3
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Wong S, Weisman LS. Roles and regulation of myosin V interaction with cargo. Adv Biol Regul 2021; 79:100787. [PMID: 33541831 PMCID: PMC7920922 DOI: 10.1016/j.jbior.2021.100787] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2021] [Accepted: 01/11/2021] [Indexed: 05/08/2023]
Abstract
A major question in cell biology is, how are organelles and large macromolecular complexes transported within a cell? Myosin V molecular motors play critical roles in the distribution of organelles, vesicles, and mRNA. Mis-localization of organelles that depend on myosin V motors underlie diseases in the skin, gut, and brain. Thus, the delivery of organelles to their proper destination is important for animal physiology and cellular function. Cargoes attach to myosin V motors via cargo specific adaptor proteins, which transiently bridge motors to their cargoes. Regulation of these adaptor proteins play key roles in the regulation of cargo transport. Emerging studies reveal that cargo adaptors play additional essential roles in the activation of myosin V, and the regulation of actin filaments. Here, we review how motor-adaptor interactions are controlled to regulate the proper loading and unloading of cargoes, as well as roles of adaptor proteins in the regulation of myosin V activity and the dynamics of actin filaments.
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Affiliation(s)
- Sara Wong
- Cell and Molecular Biology, University of Michigan, Ann Arbor, United States; Life Sciences Institute, University of Michigan, Ann Arbor, United States
| | - Lois S Weisman
- Cell and Developmental Biology, University of Michigan, Ann Arbor, United States; Life Sciences Institute, University of Michigan, Ann Arbor, United States.
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4
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Matellán L, Manzano-López J, Monje-Casas F. Polo-like kinase acts as a molecular timer that safeguards the asymmetric fate of spindle microtubule-organizing centers. eLife 2020; 9:61488. [PMID: 33135999 PMCID: PMC7669271 DOI: 10.7554/elife.61488] [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: 07/28/2020] [Accepted: 10/20/2020] [Indexed: 12/27/2022] Open
Abstract
The microtubules that form the mitotic spindle originate from microtubule-organizing centers (MTOCs) located at either pole. After duplication, spindle MTOCs can be differentially inherited during asymmetric cell division in organisms ranging from yeast to humans. Problems with establishing predetermined spindle MTOC inheritance patterns during stem cell division have been associated with accelerated cellular aging and the development of both cancer and neurodegenerative disorders. Here, we expand the repertoire of functions Polo-like kinase family members fulfill in regulating pivotal cell cycle processes. We demonstrate that the Plk1 homolog Cdc5 acts as a molecular timer that facilitates the timely and sequential recruitment of two key determinants of spindle MTOCs distribution, that is the γ-tubulin complex receptor Spc72 and the protein Kar9, and establishes the fate of these structures, safeguarding their asymmetric inheritance during Saccharomyces cerevisiae mitosis.
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Affiliation(s)
- Laura Matellán
- Centro Andaluz de Biología Molecular y Medicina Regenerativa (CABIMER) / Spanish National Research Council (CSIC) - University of Seville - University Pablo de Olavide, Sevilla, Spain
| | - Javier Manzano-López
- Centro Andaluz de Biología Molecular y Medicina Regenerativa (CABIMER) / Spanish National Research Council (CSIC) - University of Seville - University Pablo de Olavide, Sevilla, Spain
| | - Fernando Monje-Casas
- Centro Andaluz de Biología Molecular y Medicina Regenerativa (CABIMER) / Spanish National Research Council (CSIC) - University of Seville - University Pablo de Olavide, Sevilla, Spain
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5
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Schweiggert J, Panigada D, Tan AN, Liakopoulos D. Kar9 controls the nucleocytoplasmic distribution of yeast EB1. Cell Cycle 2016; 15:2860-2866. [PMID: 27625073 DOI: 10.1080/15384101.2016.1231282] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022] Open
Abstract
The precise temporal and spatial concentration of microtubule-associated proteins (MAPs) within the cell is fundamental to ensure chromosome segregation and correct spindle positioning. MAPs form an intricate web of interactions among each other and compete for binding sites on microtubules. Therefore, when assessing cellular phenotypes upon MAP up- or downregulation, it is important to consider the protein interaction network between individual MAPs. Here, we show that changes in the amounts of the spindle positioning factor Kar9 specifically affect the distribution of yeast EB1 on spindle microtubules, without influencing other microtubule-associated interacting partners of Kar9, i.e. yeast XMAP215 and CLIP-170. Alterations in the distribution of yeast EB1 explain chromosome segregation defects upon knockout, overexpression or stabilization of Kar9 and provide an example for non-linear effects on MAP behavior after perturbation of their equilibrium.
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Affiliation(s)
- Jörg Schweiggert
- a Centre de Recherche en Biologie cellulaire de Montpellier (CRBM), CNRS UMR 523 , Montpellier , France.,b Biochemistry Centre Heidelberg (BZH) , Heidelberg , Germany.,c The Hartmut Hoffmann-Berling International Graduate School of Molecular and Cellular Biology, University of Heidelberg , Heidelberg , Germany
| | - Davide Panigada
- a Centre de Recherche en Biologie cellulaire de Montpellier (CRBM), CNRS UMR 523 , Montpellier , France
| | - Ann Na Tan
- b Biochemistry Centre Heidelberg (BZH) , Heidelberg , Germany
| | - Dimitris Liakopoulos
- a Centre de Recherche en Biologie cellulaire de Montpellier (CRBM), CNRS UMR 523 , Montpellier , France.,c The Hartmut Hoffmann-Berling International Graduate School of Molecular and Cellular Biology, University of Heidelberg , Heidelberg , Germany
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6
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Manatschal C, Farcas AM, Degen MS, Bayer M, Kumar A, Landgraf C, Volkmer R, Barral Y, Steinmetz MO. Molecular basis of Kar9-Bim1 complex function during mating and spindle positioning. Mol Biol Cell 2016; 27:mbc.E16-07-0552. [PMID: 27682587 PMCID: PMC5170556 DOI: 10.1091/mbc.e16-07-0552] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2016] [Revised: 09/20/2016] [Accepted: 09/21/2016] [Indexed: 11/17/2022] Open
Abstract
The Kar9 pathway promotes nuclear fusion during mating and spindle alignment during metaphase in budding yeast. How Kar9 supports the different outcome of these two divergent processes is an open question. Here, we show that three sites in the C-terminal disordered domain of Kar9 mediate tight Kar9 interaction with the C-terminal dimerization domain of Bim1 (EB1 orthologue). Site1 and Site2 contain SxIP motifs; however, Site3 defines a novel type of EB1-binding site. Whereas Site2 and Site3 mediate Kar9 recruitment to microtubule tips, nuclear movement and karyogamy, solely Site2 functions in spindle positioning during metaphase. Site1 in turn plays an inhibitory role during mating. Additionally, the Kar9-Bim1 complex is involved in microtubule-independent activities during mating. Together, our data reveal how multiple and partially redundant EB1-binding sites provide a microtubule-associated protein with the means to modulate its biochemical properties to promote different molecular processes during cell proliferation and differentiation.
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Affiliation(s)
- Cristina Manatschal
- Laboratory of Biomolecular Research, Department of Biology and Chemistry, Paul Scherrer Institut, Villigen PSI, Switzerland
| | - Ana-Maria Farcas
- Institute of Biochemistry, Biology Department, ETH Zürich, Zürich, Switzerland
| | - Miriam Steiner Degen
- Laboratory of Biomolecular Research, Department of Biology and Chemistry, Paul Scherrer Institut, Villigen PSI, Switzerland
| | - Mathias Bayer
- Institute of Biochemistry, Biology Department, ETH Zürich, Zürich, Switzerland
| | - Anil Kumar
- Laboratory of Biomolecular Research, Department of Biology and Chemistry, Paul Scherrer Institut, Villigen PSI, Switzerland
| | - Christiane Landgraf
- Institut für Medizinische Immunologie, Charité-Universitätsmedizin Berlin, Berlin, Germany
| | - Rudolf Volkmer
- Institut für Medizinische Immunologie, Charité-Universitätsmedizin Berlin, Berlin, Germany
| | - Yves Barral
- Institute of Biochemistry, Biology Department, ETH Zürich, Zürich, Switzerland
| | - Michel O Steinmetz
- Laboratory of Biomolecular Research, Department of Biology and Chemistry, Paul Scherrer Institut, Villigen PSI, Switzerland
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7
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Dasso M. Kar9 Controls the Cytoplasm by Visiting the Nucleus. Dev Cell 2016; 36:360-1. [PMID: 26906732 DOI: 10.1016/j.devcel.2016.02.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Kar9 positions mitotic spindles during budding yeast cell division. Reporting in this issue of Developmental Cell, Schweiggert et al. (2016) show that modulation of Kar9 stability mediates crosstalk between cytoplasmic and nuclear microtubules, using an elaborate mechanism that involves regulated nuclear transport as well as SUMOylation and ubiquitination.
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Affiliation(s)
- Mary Dasso
- Division of Molecular and Cellular Biology, National Institute for Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892, USA.
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8
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Regulation of a Spindle Positioning Factor at Kinetochores by SUMO-Targeted Ubiquitin Ligases. Dev Cell 2016; 36:415-27. [PMID: 26906737 DOI: 10.1016/j.devcel.2016.01.011] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2015] [Revised: 12/04/2015] [Accepted: 01/14/2016] [Indexed: 12/17/2022]
Abstract
Correct function of the mitotic spindle requires balanced interplay of kinetochore and astral microtubules that mediate chromosome segregation and spindle positioning, respectively. Errors therein can cause severe defects ranging from aneuploidy to developmental disorders. Here, we describe a protein degradation pathway that functionally links astral microtubules to kinetochores via regulation of a microtubule-associated factor. We show that the yeast spindle positioning protein Kar9 localizes not only to astral but also to kinetochore microtubules, where it becomes targeted for proteasomal degradation by the SUMO-targeted ubiquitin ligases (STUbLs) Slx5-Slx8. Intriguingly, this process does not depend on preceding sumoylation of Kar9 but rather requires SUMO-dependent recruitment of STUbLs to kinetochores. Failure to degrade Kar9 leads to defects in both chromosome segregation and spindle positioning. We propose that kinetochores serve as platforms to recruit STUbLs in a SUMO-dependent manner in order to ensure correct spindle function by regulating levels of microtubule-associated proteins.
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9
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Alonso A, Greenlee M, Matts J, Kline J, Davis KJ, Miller RK. Emerging roles of sumoylation in the regulation of actin, microtubules, intermediate filaments, and septins. Cytoskeleton (Hoboken) 2015; 72:305-39. [PMID: 26033929 PMCID: PMC5049490 DOI: 10.1002/cm.21226] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2014] [Revised: 05/25/2015] [Accepted: 05/27/2015] [Indexed: 12/29/2022]
Abstract
Sumoylation is a powerful regulatory system that controls many of the critical processes in the cell, including DNA repair, transcriptional regulation, nuclear transport, and DNA replication. Recently, new functions for SUMO have begun to emerge. SUMO is covalently attached to components of each of the four major cytoskeletal networks, including microtubule-associated proteins, septins, and intermediate filaments, in addition to nuclear actin and actin-regulatory proteins. However, knowledge of the mechanisms by which this signal transduction system controls the cytoskeleton is still in its infancy. One story that is beginning to unfold is that SUMO may regulate the microtubule motor protein dynein by modification of its adaptor Lis1. In other instances, cytoskeletal elements can both bind to SUMO non-covalently and also be conjugated by it. The molecular mechanisms for many of these new functions are not yet clear, but are under active investigation. One emerging model links the function of MAP sumoylation to protein degradation through SUMO-targeted ubiquitin ligases, also known as STUbL enzymes. Other possible functions for cytoskeletal sumoylation are also discussed.
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Affiliation(s)
- Annabel Alonso
- Department of Biochemistry and Molecular BiologyOklahoma State UniversityStillwaterOklahoma
| | - Matt Greenlee
- Department of Biochemistry and Molecular BiologyOklahoma State UniversityStillwaterOklahoma
| | - Jessica Matts
- Department of Biochemistry and Molecular BiologyOklahoma State UniversityStillwaterOklahoma
| | - Jake Kline
- Department of Biochemistry and Molecular BiologyOklahoma State UniversityStillwaterOklahoma
| | - Kayla J. Davis
- Department of Biochemistry and Molecular BiologyOklahoma State UniversityStillwaterOklahoma
| | - Rita K. Miller
- Department of Biochemistry and Molecular BiologyOklahoma State UniversityStillwaterOklahoma
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10
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Stevermann L, Liakopoulos D. Molecular mechanisms in spindle positioning: structures and new concepts. Curr Opin Cell Biol 2012; 24:816-24. [PMID: 23142476 DOI: 10.1016/j.ceb.2012.10.005] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2012] [Revised: 10/08/2012] [Accepted: 10/15/2012] [Indexed: 10/27/2022]
Abstract
Coordination of cell cleavage with respect to cell geometry, cell polarity and neighboring tissues is critical for tissue maintenance, malignant transformation and metastasis. The position of the mitotic spindle within the cell determines where cell cleavage occurs. Spindle positioning is often mediated through capture of astral microtubules by motor proteins at the cell cortex. Recently, the core dynein anchor complex has been structurally resolved. Junctional complexes were shown to provide additional capture sites for astral microtubules in proliferating tissues. Finally, latest studies show that signals from centrosomes control spindle positioning and propose novel concepts for generation of centrosome identity.
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Affiliation(s)
- Lea Stevermann
- Heidelberg University Biochemistry Center (BZH) INF 328, 69120 Heidelberg, Germany
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11
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Abstract
The Saccharomyces cerevisiae mitotic spindle in budding yeast is exemplified by its simplicity and elegance. Microtubules are nucleated from a crystalline array of proteins organized in the nuclear envelope, known as the spindle pole body in yeast (analogous to the centrosome in larger eukaryotes). The spindle has two classes of nuclear microtubules: kinetochore microtubules and interpolar microtubules. One kinetochore microtubule attaches to a single centromere on each chromosome, while approximately four interpolar microtubules emanate from each pole and interdigitate with interpolar microtubules from the opposite spindle to provide stability to the bipolar spindle. On the cytoplasmic face, two to three microtubules extend from the spindle pole toward the cell cortex. Processes requiring microtubule function are limited to spindles in mitosis and to spindle orientation and nuclear positioning in the cytoplasm. Microtubule function is regulated in large part via products of the 6 kinesin gene family and the 1 cytoplasmic dynein gene. A single bipolar kinesin (Cin8, class Kin-5), together with a depolymerase (Kip3, class Kin-8) or minus-end-directed kinesin (Kar3, class Kin-14), can support spindle function and cell viability. The remarkable feature of yeast cells is that they can survive with microtubules and genes for just two motor proteins, thus providing an unparalleled system to dissect microtubule and motor function within the spindle machine.
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12
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Hotz M, Leisner C, Chen D, Manatschal C, Wegleiter T, Ouellet J, Lindstrom D, Gottschling DE, Vogel J, Barral Y. Spindle pole bodies exploit the mitotic exit network in metaphase to drive their age-dependent segregation. Cell 2012; 148:958-72. [PMID: 22385961 PMCID: PMC3779431 DOI: 10.1016/j.cell.2012.01.041] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2011] [Revised: 10/18/2011] [Accepted: 01/30/2012] [Indexed: 11/19/2022]
Abstract
Like many asymmetrically dividing cells, budding yeast segregates mitotic spindle poles nonrandomly between mother and daughter cells. During metaphase, the spindle positioning protein Kar9 accumulates asymmetrically, localizing specifically to astral microtubules emanating from the old spindle pole body (SPB) and driving its segregation to the bud. Here, we show that the SPB component Nud1/centriolin acts through the mitotic exit network (MEN) to specify asymmetric SPB inheritance. In the absence of MEN signaling, Kar9 asymmetry is unstable and its preference for the old SPB is disrupted. Consistent with this, phosphorylation of Kar9 by the MEN kinases Dbf2 and Dbf20 is not required to break Kar9 symmetry but is instead required to maintain stable association of Kar9 with the old SPB throughout metaphase. We propose that MEN signaling links Kar9 regulation to SPB identity through biasing and stabilizing the age-insensitive, cyclin-B-dependent mechanism of symmetry breaking.
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Affiliation(s)
- Manuel Hotz
- Institute of Biochemistry, Biology Department, ETH Zurich, 8093 Zurich, Switzerland
| | - Christian Leisner
- Institute of Biochemistry, Biology Department, ETH Zurich, 8093 Zurich, Switzerland
| | - Daici Chen
- Department of Biology, McGill University, Montreal, Quebec H3G 0B1, Canada
| | - Cristina Manatschal
- Institute of Biochemistry, Biology Department, ETH Zurich, 8093 Zurich, Switzerland
| | - Thomas Wegleiter
- Institute of Biochemistry, Biology Department, ETH Zurich, 8093 Zurich, Switzerland
| | - Jimmy Ouellet
- Institute of Biochemistry, Biology Department, ETH Zurich, 8093 Zurich, Switzerland
| | - Derek Lindstrom
- Division of Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, WA 98109, USA
| | - Dan E. Gottschling
- Division of Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, WA 98109, USA
| | - Jackie Vogel
- Department of Biology, McGill University, Montreal, Quebec H3G 0B1, Canada
| | - Yves Barral
- Institute of Biochemistry, Biology Department, ETH Zurich, 8093 Zurich, Switzerland
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13
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Merlini L, Piatti S. The mother-bud neck as a signaling platform for the coordination between spindle position and cytokinesis in budding yeast. Biol Chem 2012; 392:805-12. [PMID: 21824008 DOI: 10.1515/bc.2011.090] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
During asymmetric cell division, spindle positioning is critical for ensuring the unequal inheritance of polarity factors. In budding yeast, the mother-bud neck determines the cleavage plane and a correct nuclear division between mother and daughter cell requires orientation of the mitotic spindle along the mother-bud axis. A surveillance device called the spindle position/orientation checkpoint (SPOC) oversees this process and delays mitotic exit and cytokinesis until the spindle is properly oriented along the division axis, thus ensuring genome stability. Cytoskeletal proteins called septins form a ring at the bud neck that is essential for cytokinesis. Furthermore, septins and septin-associated proteins are implicated in spindle positioning and SPOC. In this review, we discuss the emerging connections between septins and the SPOC and the role of the mother-bud neck as a signaling platform to couple proper chromosome segregation to cytokinesis.
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Affiliation(s)
- Laura Merlini
- Dipartimento di Biotecnologie e Bioscienze, Università di Milano-Bicocca, Milan, Italy
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14
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Jiang K, Akhmanova A. Microtubule tip-interacting proteins: a view from both ends. Curr Opin Cell Biol 2011; 23:94-101. [PMID: 20817499 DOI: 10.1016/j.ceb.2010.08.008] [Citation(s) in RCA: 90] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2010] [Accepted: 08/08/2010] [Indexed: 10/19/2022]
Abstract
Microtubule ends serve as sites of tubulin addition and removal, and at the same time play crucial roles in microtubule capture, stabilization and attachment to different cellular structures. Microtubule plus and minus-ends possess distinct structural and dynamic properties, and are recognized, bound and regulated by diverse factors. These include specific capping factors such as γ-tubulin, motors, such as plus-end and minus-end directed kinesins, highly specialized kinetochore-bound microtubule-associated proteins, and comet-making plus-end tracking proteins such as EB1 and its partners. Here, we provide an overview of microtubule tip-interacting proteins and the mechanisms responsible for their association with microtubule ends, and discuss the functional cross-talk between microtubule plus and minus-end binding factors.
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Affiliation(s)
- Kai Jiang
- Department of Cell Biology, Erasmus Medical Center, P.O. Box 2040, 3000 CA Rotterdam, The Netherlands
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15
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Hotz M, Barral Y. Cytokinesis: the Ubc of positioning. Curr Biol 2010; 20:R602-4. [PMID: 20656203 DOI: 10.1016/j.cub.2010.06.009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
A recent analysis of spindle positioning in yeast sheds light on how interactions between microtubules and the cleavage apparatus are modulated through mitosis to promote and maintain proper positioning of the spindle and cleavage plane relative to each other.
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Affiliation(s)
- Manuel Hotz
- Institute of Biochemistry, Department of Biology, ETH Zurich, Schafmattstrasse 18, 8093, Zurich, Switzerland
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16
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Gouveia SM, Akhmanova A. Cell and Molecular Biology of Microtubule Plus End Tracking Proteins. INTERNATIONAL REVIEW OF CELL AND MOLECULAR BIOLOGY 2010; 285:1-74. [DOI: 10.1016/b978-0-12-381047-2.00001-3] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
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