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Manzano-López J, Matellán L, Álvarez-Llamas A, Blanco-Mira JC, Monje-Casas F. Asymmetric inheritance of spindle microtubule-organizing centres preserves replicative lifespan. Nat Cell Biol 2019; 21:952-965. [DOI: 10.1038/s41556-019-0364-8] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2018] [Accepted: 06/23/2019] [Indexed: 12/19/2022]
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Lengefeld J, Yen E, Chen X, Leary A, Vogel J, Barral Y. Spatial cues and not spindle pole maturation drive the asymmetry of astral microtubules between new and preexisting spindle poles. Mol Biol Cell 2017; 29:10-28. [PMID: 29142076 PMCID: PMC5746063 DOI: 10.1091/mbc.e16-10-0725] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2017] [Revised: 10/31/2017] [Accepted: 11/07/2017] [Indexed: 11/17/2022] Open
Abstract
The distinct behavior of the spindle pole bodies (SPBs) during spindle orientation in yeast metaphase does not result from them being differently mature, but astral microtubule organization correlates with the subcellular position rather than the age of the SPBs. In many asymmetrically dividing cells, the microtubule-organizing centers (MTOCs; mammalian centrosome and yeast spindle pole body [SPB]) nucleate more astral microtubules on one of the two spindle poles than the other. This differential activity generally correlates with the age of MTOCs and contributes to orienting the mitotic spindle within the cell. The asymmetry might result from the two MTOCs being in distinctive maturation states. We investigated this model in budding yeast. Using fluorophores with different maturation kinetics to label the outer plaque components of the SPB, we found that the Cnm67 protein is mobile, whereas Spc72 is not. However, these two proteins were rapidly as abundant on both SPBs, indicating that SPBs mature more rapidly than anticipated. Superresolution microscopy confirmed this finding for Spc72 and for the γ-tubulin complex. Moreover, astral microtubule number and length correlated with the subcellular localization of SPBs rather than their age. Kar9-dependent orientation of the spindle drove the differential activity of the SPBs in astral microtubule organization rather than intrinsic differences between the spindle poles. Together, our data establish that Kar9 and spatial cues, rather than the kinetics of SPB maturation, control the asymmetry of astral microtubule organization between the preexisting and new SPBs.
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Affiliation(s)
- Jette Lengefeld
- Department of Biology, Institute of Biochemistry, ETH Zurich, 8093 Zurich, Switzerland
| | - Eric Yen
- Department of Biology, McGill University, Montreal, QC H3G 0B1, Canada
| | - Xiuzhen Chen
- Department of Biology, Institute of Biochemistry, ETH Zurich, 8093 Zurich, Switzerland
| | - Allen Leary
- Department of Biology, McGill University, Montreal, QC H3G 0B1, Canada
| | - Jackie Vogel
- Department of Biology, McGill University, Montreal, QC H3G 0B1, Canada
| | - Yves Barral
- Department of Biology, Institute of Biochemistry, ETH Zurich, 8093 Zurich, Switzerland
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Fukuda Y, Luchniak A, Murphy ER, Gupta ML. Spatial control of microtubule length and lifetime by opposing stabilizing and destabilizing functions of Kinesin-8. Curr Biol 2014; 24:1826-35. [PMID: 25088560 DOI: 10.1016/j.cub.2014.06.069] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2014] [Revised: 05/24/2014] [Accepted: 06/27/2014] [Indexed: 11/20/2022]
Abstract
BACKGROUND To function in diverse cellular processes, the dynamic behavior of microtubules (MTs) must be differentially regulated within the cell. In budding yeast, the spindle position checkpoint (SPOC) inhibits mitotic exit in response to mispositioned spindles. To maintain SPOC-mediated anaphase arrest, astral MTs must maintain persistent interactions with and/or extend through the bud neck. However, the molecular mechanisms that ensure the stability of these interactions are not known. RESULTS The presence of an MT extending through and/or interacting with the bud neck is maintained by spatial control of catastrophe and rescue, which extends MT lifetime >25-fold and controls the length of dynamic MTs within the bud compartment. Moreover, the single kinesin-8 motor Kip3 alternately mediates both catastrophe and rescue of the bud MT. Kip3 accumulates in a length-dependent manner along the lattice of MTs within the bud, yet induces catastrophe spatially near the bud tip. Rather, this accumulation of Kip3 facilitates its association with depolymerizing MT plus ends, where Kip3 promotes rescue before MTs exit the bud. MT rescue within the bud requires the tail domain of Kip3, whereas the motor domain mediates catastrophe at the bud tip. In vitro, Kip3 exerts both stabilizing and destabilizing effects on reconstituted yeast MTs. CONCLUSIONS The kinesin-8 Kip3 is a multifunctional regulator that differentially stabilizes and destabilizes specific MTs. Control over MT catastrophe and rescue by Kip3 defines the length and lifetime of MTs within the bud compartment of cells with mispositioned spindles. This subcellular regulation of MT dynamics is critical to maintaining mitotic arrest in response to mispositioned spindles.
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Affiliation(s)
- Yusuke Fukuda
- Department of Molecular Genetics and Cell Biology, University of Chicago, Chicago, IL 60637, USA
| | - Anna Luchniak
- Department of Biochemistry and Molecular Biology, University of Chicago, Chicago, IL 60637, USA
| | - Erin R Murphy
- Department of Molecular Genetics and Cell Biology, University of Chicago, Chicago, IL 60637, USA
| | - Mohan L Gupta
- Department of Molecular Genetics and Cell Biology, University of Chicago, Chicago, IL 60637, USA.
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Bajpai A, Feoktistova A, Chen JS, McCollum D, Sato M, Carazo-Salas RE, Gould KL, Csikász-Nagy A. Dynamics of SIN asymmetry establishment. PLoS Comput Biol 2013; 9:e1003147. [PMID: 23874188 PMCID: PMC3708865 DOI: 10.1371/journal.pcbi.1003147] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2013] [Accepted: 06/05/2013] [Indexed: 01/18/2023] Open
Abstract
Timing of cell division is coordinated by the Septation Initiation Network (SIN) in fission yeast. SIN activation is initiated at the two spindle pole bodies (SPB) of the cell in metaphase, but only one of these SPBs contains an active SIN in anaphase, while SIN is inactivated in the other by the Cdc16-Byr4 GAP complex. Most of the factors that are needed for such asymmetry establishment have been already characterized, but we lack the molecular details that drive such quick asymmetric distribution of molecules at the two SPBs. Here we investigate the problem by computational modeling and, after establishing a minimal system with two antagonists that can drive reliable asymmetry establishment, we incorporate the current knowledge on the basic SIN regulators into an extended model with molecular details of the key regulators. The model can capture several peculiar earlier experimental findings and also predicts the behavior of double and triple SIN mutants. We experimentally tested one prediction, that phosphorylation of the scaffold protein Cdc11 by a SIN kinase and the core cell cycle regulatory Cyclin dependent kinase (Cdk) can compensate for mutations in the SIN inhibitor Cdc16 with different efficiencies. One aspect of the prediction failed, highlighting a potential hole in our current knowledge. Further experimental tests revealed that SIN induced Cdc11 phosphorylation might have two separate effects. We conclude that SIN asymmetry is established by the antagonistic interactions between SIN and its inhibitor Cdc16-Byr4, partially through the regulation of Cdc11 phosphorylation states.
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Affiliation(s)
- Archana Bajpai
- The Microsoft Research-University of Trento Centre for Computational Systems Biology, Piazza Manifattura 1, Rovereto, Italy
| | - Anna Feoktistova
- Howard Hughes Medical Institute and Department of Cell and Developmental Biology, Vanderbilt University, Nashville, Tennessee, United States of America
| | - Jun-Song Chen
- Howard Hughes Medical Institute and Department of Cell and Developmental Biology, Vanderbilt University, Nashville, Tennessee, United States of America
| | - Dannel McCollum
- Department of Microbiology and Physiological Systems and Program in Cell Dynamics, University of Massachusetts Medical School, Worcester, Massachusetts, United States of America
| | - Masamitsu Sato
- Department of Biophysics and Biochemistry, University of Tokyo, Tokyo, Japan
- Department of Life Science and Medical Bioscience, Waseda University, Tokyo, Japan
| | | | - Kathleen L. Gould
- Howard Hughes Medical Institute and Department of Cell and Developmental Biology, Vanderbilt University, Nashville, Tennessee, United States of America
| | - Attila Csikász-Nagy
- The Microsoft Research-University of Trento Centre for Computational Systems Biology, Piazza Manifattura 1, Rovereto, Italy
- Department of Computational Biology, Research and Innovation Center, Fondazione Edmund Mach, San Michele all'Adige, Italy
- Randall Division of Cell and Molecular Biophysics and Institute for Mathematical and Molecular Biomedicine, King's College London, London, United Kingdom
- * E-mail:
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Aurora kinase inhibitors reveal mechanisms of HURP in nucleation of centrosomal and kinetochore microtubules. Proc Natl Acad Sci U S A 2013; 110:E1779-87. [PMID: 23610398 DOI: 10.1073/pnas.1220523110] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The overexpression of Aurora kinases in multiple tumors makes these kinases appealing targets for the development of anticancer therapies. This study identified two small molecules with a furanopyrimidine core, IBPR001 and IBPR002, that target Aurora kinases and induce a DFG conformation change at the ATP site of Aurora A. Our results demonstrate the high potency of the IBPR compounds in reducing tumorigenesis in a colorectal cancer xenograft model in athymic nude mice. Human hepatoma up-regulated protein (HURP) is a substrate of Aurora kinase A, which plays a crucial role in the stabilization of kinetochore fibers. This study used the IBPR compounds as well as MLN8237, a proven Aurora A inhibitor, as chemical probes to investigate the molecular role of HURP in mitotic spindle formation. These compounds effectively eliminated HURP phosphorylation, thereby revealing the coexistence and continuous cycling of HURP between unphosphorylated and phosphorylated forms that are associated, respectively, with microtubules emanating from centrosomes and kinetochores. Furthermore, these compounds demonstrate a spatial hierarchical preference for HURP in the attachment of microtubules extending from the mother to the daughter centrosome. The finding of inequality in the centrosomal microtubules revealed by these small molecules provides a versatile tool for the discovery of new cell-division molecules for the development of antitumor drugs.
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Tartakoff AM, Aylyarov I, Jaiswal P. Septin-containing barriers control the differential inheritance of cytoplasmic elements. Cell Rep 2012; 3:223-36. [PMID: 23273916 DOI: 10.1016/j.celrep.2012.11.022] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2012] [Revised: 09/27/2012] [Accepted: 11/27/2012] [Indexed: 01/12/2023] Open
Abstract
Fusion of haploid cells of Saccharomyces cerevisiae generates zygotes. We observe that the zygote midzone includes a septin annulus and differentially affects redistribution of supramolecular complexes and organelles. Redistribution across the midzone of supramolecular complexes (polysomes and Sup35p-GFP [PSI+]) is unexpectedly delayed relative to soluble proteins; however, in [psi-] × [PSI+] crosses, all buds eventually receive Sup35p-GFP [PSI+]. Encounter between parental mitochondria is further delayed until septins relocate to the bud site, where they are required for repolarization of the actin cytoskeleton. This delay allows rationalization of the longstanding observation that terminal zygotic buds preferentially inherit a single mitochondrial genotype. The rate of redistribution of complexes and organelles determines whether their inheritance will be uniform.
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Affiliation(s)
- Alan Michael Tartakoff
- Pathology Department and Cell Biology Program, Case Western Reserve University, 2103 Cornell Road, Cleveland, OH 44106, USA.
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Spatiotemporal analysis of organelle and macromolecular complex inheritance. Proc Natl Acad Sci U S A 2012; 110:175-80. [PMID: 23248297 DOI: 10.1073/pnas.1207424110] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
Following mitosis, daughter cells must inherit a functional set of essential proteins and organelles. We applied a genetic tool to simultaneously monitor the kinetics and distribution of old and new proteins marking all intracellular compartments in budding yeasts. Most organelles followed a general pattern whereby preexisting proteins are symmetrically partitioned followed by template-based incorporation of new proteins. Peroxisomes belong to this group, supporting a model of biogenesis by growth and division from preexisting peroxisomes. We detected two exceptions: the nuclear pore complex (NPC) and the spindle pole body (SPB). Old NPCs are stably inherited during successive generations but remained separated from new NPCs, which are incorporated de novo in mother and daughter cells. Only the SPB displayed asymmetrical distribution, with old components primarily inherited by daughter cells and new proteins equally incorporated in both cells. Our analysis resolves conflicting models (peroxisomes, NPC) and reveals unique patterns (NPC, SPB) of organelle inheritance.
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Abstract
Cell polarity is crucial for many functions including cell migration, tissue organization and asymmetric cell division. In animal cells, cell polarity is controlled by the highly conserved PAR (PARtitioning defective) proteins. par genes have been identified in Caenorhabditis elegans in screens for maternal lethal mutations that disrupt cytoplasmic partitioning and asymmetric division. Although PAR proteins were identified more than 20 years ago, our understanding on how they regulate polarity and how they are regulated is still incomplete. In this chapter we review our knowledge of the processes of cell polarity establishment and maintenance, and asymmetric cell division in the early C. elegans embryo. We discuss recent findings that highlight new players in cell polarity and/or reveal the molecular details on how PAR proteins regulate polarity processes.
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Cortés JCG, Sato M, Muñoz J, Moreno MB, Clemente-Ramos JA, Ramos M, Okada H, Osumi M, Durán A, Ribas JC. Fission yeast Ags1 confers the essential septum strength needed for safe gradual cell abscission. ACTA ACUST UNITED AC 2012; 198:637-56. [PMID: 22891259 PMCID: PMC3514033 DOI: 10.1083/jcb.201202015] [Citation(s) in RCA: 74] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/03/2022]
Abstract
The α(1-3)glucan synthase Ags1 is essential for both secondary septum
formation and the primary septum structural strength needed to counter cell
turgor pressure during cell separation. Fungal cytokinesis requires the assembly of a dividing septum wall. In yeast, the
septum has to be selectively digested during the critical cell separation
process. Fission yeast cell wall α(1-3)glucan is essential, but nothing
is known about its localization and function in the cell wall or about
cooperation between the α- and β(1-3)glucan synthases Ags1 and Bgs
for cell wall and septum assembly. Here, we generate a physiological Ags1-GFP
variant and demonstrate a tight colocalization with Bgs1, suggesting a
cooperation in the important early steps of septum construction. Moreover, we
define the essential functions of α(1-3)glucan in septation and cell
separation. We show that α(1-3)glucan is essential for both secondary
septum formation and the primary septum structural strength needed to support
the physical forces of the cell turgor pressure during cell separation.
Consequently, the absence of Ags1 and therefore α(1-3)glucan generates a
special and unique side-explosive cell separation due to an instantaneous
primary septum tearing caused by the turgor pressure.
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Affiliation(s)
- Juan Carlos G Cortés
- Instituto de Biología Funcional y Genómica, Consejo Superior de Investigaciones Científicas (CSIC)/Universidad de Salamanca, 37007 Salamanca, Spain
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Hotz M, Lengefeld J, Barral Y. The MEN mediates the effects of the spindle assembly checkpoint on Kar9-dependent spindle pole body inheritance in budding yeast. Cell Cycle 2012; 11:3109-16. [PMID: 22871738 DOI: 10.4161/cc.21504] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Many asymmetrically dividing cells segregate the poles of the mitotic spindle non-randomly between their two daughters. In budding yeast, the protein Kar9 localizes almost exclusively to the astral microtubules emanating from the old spindle pole body (SPB) and promotes its movement toward the bud. Thereby, Kar9 orients the spindle relative to the division axis. Here, we show that beyond perturbing Kar9 distribution, activation of the spindle assembly checkpoint (SAC) randomizes SPB inheritance. Inactivation of the B-type cyclin Clb5 led to a SAC-dependent defect in Kar9 orientation and SPB segregation. Furthermore, unlike the Clb4-dependent pathway, the Clb5- and SAC-dependent pathways functioned genetically upstream of the mitotic exit network (MEN) in SPB specification and Kar9-dependent SPB inheritance. Together, our study indicates that Clb5 functions in spindle assembly and that the SAC controls the specification and inheritance of yeast SPBs through inhibition of the MEN.
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Affiliation(s)
- Manuel Hotz
- Institute of Biochemistry, Biology Department, ETH Zurich, Zurich, Switzerland
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Ouellet J, Barral Y. Organelle segregation during mitosis: lessons from asymmetrically dividing cells. ACTA ACUST UNITED AC 2012; 196:305-13. [PMID: 22312002 PMCID: PMC3275374 DOI: 10.1083/jcb.201102078] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Studies on cell division traditionally focus on the mechanisms of chromosome segregation and cytokinesis, yet we know comparatively little about how organelles segregate. Analysis of organelle partitioning in asymmetrically dividing cells has provided insights into the mechanisms through which cells control organelle distribution. Interestingly, these studies have revealed that segregation mechanisms frequently link organelle distribution to organelle growth and formation. Furthermore, in many cases, cells use organelles, such as the endoplasmic reticulum and P granules, as vectors for the segregation of information. Together, these emerging data suggest that the coordination between organelle growth, division, and segregation plays an important role in the control of cell fate inheritance, cellular aging, and rejuvenation, i.e., the resetting of age in immortal lineages.
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Affiliation(s)
- Jimmy Ouellet
- Institute of Biochemistry, Department of Biology, Eidgenössische Technische Hochschule Zürich, 8093 Zurich, Switzerland
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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: 57] [Impact Index Per Article: 4.8] [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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Cell-Cycle Control in Oocytes and During Early Embryonic Cleavage Cycles in Ascidians. INTERNATIONAL REVIEW OF CELL AND MOLECULAR BIOLOGY 2012; 297:235-64. [DOI: 10.1016/b978-0-12-394308-8.00006-6] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
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14
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Fly meets yeast: checking the correct orientation of cell division. Trends Cell Biol 2011; 21:526-33. [PMID: 21705221 DOI: 10.1016/j.tcb.2011.05.004] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2011] [Revised: 05/18/2011] [Accepted: 05/24/2011] [Indexed: 12/13/2022]
Abstract
Cell division is generally thought to be a process that produces an exact copy of the mother cell by precisely replicating its genomic DNA, doubling organelles, and segregating them into two cells. Many cell types from bacteria to human cells divide asymmetrically, however, to generate daughter cells with distinct characteristics. Such asymmetric divisions are fundamental to the lifespan of a cell, to embryonic development, and to stem cell homeostasis. Asymmetric division requires coordination of cellular asymmetry and the cell division machinery. Accumulating evidence suggests that the basic molecular mechanisms that govern this process are conserved from yeast to humans. In this review we highlight similarities in the mechanisms of asymmetric cell division in yeast and Drosophila male germline stem cells (GSCs) in the hope of extracting common themes underlying several systems.
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