1
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Hu Q, Xu Y, Song M, Dai Y, Antebi A, Shen Y. BLMP-1 is a critical temporal regulator of dietary-restriction-induced response in Caenorhabditis elegans. Cell Rep 2024; 43:113959. [PMID: 38483903 DOI: 10.1016/j.celrep.2024.113959] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2023] [Revised: 02/07/2024] [Accepted: 02/28/2024] [Indexed: 04/02/2024] Open
Abstract
The extrinsic diet and the intrinsic developmental programs are intertwined. Although extensive research has been conducted on how nutrition regulates development, whether and how developmental programs control the timing of nutritional responses remain barely known. Here, we report that a developmental timing regulator, BLMP-1/BLIMP1, governs the temporal response to dietary restriction (DR). At the end of larval development, BLMP-1 is induced and interacts with DR-activated PHA-4/FOXA, a key transcription factor responding to the reduced nutrition. By integrating temporal and nutritional signaling, the DR response regulates many development-related genes, including gska-3/GSK3β, through BLMP-1-PHA-4 at the onset of adulthood. Upon DR, a precocious activation of BLMP-1 in early larval stages impairs neuronal development through gska-3, whereas the increase of gska-3 by BLMP-1-PHA-4 at the last larval stage suppresses WNT signaling in adulthood for DR-induced longevity. Our findings reveal a temporal checkpoint of the DR response that protects larval development and promotes adult health.
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Affiliation(s)
- Qingyuan Hu
- State Key Laboratory of Cell Biology, Shanghai Institute of Biochemistry and Cell Biology, Center for Excellence in Molecular Cell Science, Chinese Academy of Sciences, Shanghai 200031, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yunpeng Xu
- State Key Laboratory of Cell Biology, Shanghai Institute of Biochemistry and Cell Biology, Center for Excellence in Molecular Cell Science, Chinese Academy of Sciences, Shanghai 200031, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Mengjiao Song
- State Key Laboratory of Cell Biology, Shanghai Institute of Biochemistry and Cell Biology, Center for Excellence in Molecular Cell Science, Chinese Academy of Sciences, Shanghai 200031, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yumin Dai
- State Key Laboratory of Cell Biology, Shanghai Institute of Biochemistry and Cell Biology, Center for Excellence in Molecular Cell Science, Chinese Academy of Sciences, Shanghai 200031, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Adam Antebi
- Max Planck Institute for Biology of Ageing, 50931 Cologne, Germany; Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD), University of Cologne, 50674 Cologne, Germany
| | - Yidong Shen
- State Key Laboratory of Cell Biology, Shanghai Institute of Biochemistry and Cell Biology, Center for Excellence in Molecular Cell Science, Chinese Academy of Sciences, Shanghai 200031, China; University of Chinese Academy of Sciences, Beijing 100049, China.
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2
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Li S, Kasciukovic T, Tanaka TU. Kinetochore-microtubule error correction for biorientation: lessons from yeast. Biochem Soc Trans 2024; 52:29-39. [PMID: 38305688 PMCID: PMC10903472 DOI: 10.1042/bst20221261] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2023] [Revised: 01/11/2024] [Accepted: 01/15/2024] [Indexed: 02/03/2024]
Abstract
Accurate chromosome segregation in mitosis relies on sister kinetochores forming stable attachments to microtubules (MTs) extending from opposite spindle poles and establishing biorientation. To achieve this, erroneous kinetochore-MT interactions must be resolved through a process called error correction, which dissolves improper kinetochore-MT attachment and allows new interactions until biorientation is achieved. The Aurora B kinase plays key roles in driving error correction by phosphorylating Dam1 and Ndc80 complexes, while Mps1 kinase, Stu2 MT polymerase and phosphatases also regulate this process. Once biorientation is formed, tension is applied to kinetochore-MT interaction, stabilizing it. In this review article, we discuss the mechanisms of kinetochore-MT interaction, error correction and biorientation. We focus mainly on recent insights from budding yeast, where the attachment of a single MT to a single kinetochore during biorientation simplifies the analysis of error correction mechanisms.
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Affiliation(s)
- Shuyu Li
- Division of Molecular, Cell and Developmental Biology, School of Life Sciences, University of Dundee, Dow Street, Dundee DD1 5EH, U.K
| | - Taciana Kasciukovic
- Division of Molecular, Cell and Developmental Biology, School of Life Sciences, University of Dundee, Dow Street, Dundee DD1 5EH, U.K
| | - Tomoyuki U. Tanaka
- Division of Molecular, Cell and Developmental Biology, School of Life Sciences, University of Dundee, Dow Street, Dundee DD1 5EH, U.K
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3
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Ide AH, DeLuca KF, Wiggan O, Markus SM, DeLuca JG. The role of kinetochore dynein in checkpoint silencing is restricted to disassembly of the corona. Mol Biol Cell 2023; 34:ar76. [PMID: 37126397 PMCID: PMC10295480 DOI: 10.1091/mbc.e23-04-0130] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2023] [Accepted: 04/20/2023] [Indexed: 05/02/2023] Open
Abstract
During mitosis, kinetochore-microtubule attachments are monitored by a molecular surveillance system known as the spindle assembly checkpoint. The prevailing model posits that dynein evicts checkpoint proteins (e.g., Mad1, Mad2) from stably attached kinetochores by transporting them away from kinetochores, thus contributing to checkpoint silencing. However, the mechanism by which dynein performs this function, and its precise role in checkpoint silencing remain unresolved. Here, we find that dynein's role in checkpoint silencing is restricted to evicting checkpoint effectors from the fibrous corona, and not the outer kinetochore. Dynein evicts these molecules from the corona in a manner that does not require stable, end-on microtubule attachments. Thus, by disassembling the corona through indiscriminate microtubule encounters, dynein primes the checkpoint signaling apparatus so it can respond to stable end-on microtubule attachments and permit cells to progress through mitosis. Accordingly, we find that dynein function in checkpoint silencing becomes largely dispensable in cells in which checkpoint effectors are excluded from the corona.
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Affiliation(s)
- Amy H. Ide
- Department of Biochemistry and Molecular Biology, Colorado State University, Fort Collins, Colorado 80523
| | - Keith F. DeLuca
- Department of Biochemistry and Molecular Biology, Colorado State University, Fort Collins, Colorado 80523
| | - O’Neil Wiggan
- Department of Biochemistry and Molecular Biology, Colorado State University, Fort Collins, Colorado 80523
| | - Steven M. Markus
- Department of Biochemistry and Molecular Biology, Colorado State University, Fort Collins, Colorado 80523
| | - Jennifer G. DeLuca
- Department of Biochemistry and Molecular Biology, Colorado State University, Fort Collins, Colorado 80523
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4
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Kamakura N, Takahashi M, Jo M. The toxicity of dysregulated Plk1 activity revealed by its suppressor mutations. Genes Cells 2023. [PMID: 37119463 DOI: 10.1111/gtc.13032] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2022] [Revised: 03/15/2023] [Accepted: 04/13/2023] [Indexed: 05/01/2023]
Abstract
Polo-like kinase 1 (Plk1) is a mitotic kinase that has multiple functions throughout the cell cycle. Catalytic activation of Plk1 is known to be regulated by phosphorylation of the kinase domain, including Thr210, and by releasing the kinase domain from its inhibitory polo-box domain. However, how Plk1 is activated to fulfill its proper roles, in time and space, is not well understood. In this study, we unintentionally found that the expression of a constitutively active form of human Plk1 is toxic to bacterial cells, such that cells contained point mutations that alleviate the kinase activity. Structural prediction revealed that these mutations are adjacent to the amino acids supporting the kinase activity. When human cells express these mutants, we found decreased levels of Plk1's substrate phosphorylation, resulting in mitotic defects. Moreover, unlike in bacterial cells, the expression of activated Plk1 mutants did not affect cell proliferation in human cells unless localized at the right place in mitosis. Our observations identified new suppressor mutations and underscored the importance of spatiotemporal regulation in Plk1, providing a basis for how we might intervene in this kinase for therapeutic purpose in human cells.
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Affiliation(s)
- Nana Kamakura
- Division of Experimental Pathology, Cancer Institute, Japanese Foundation for Cancer Research, Tokyo, Japan
| | - Motoko Takahashi
- Division of Experimental Pathology, Cancer Institute, Japanese Foundation for Cancer Research, Tokyo, Japan
| | - Minji Jo
- Division of Experimental Pathology, Cancer Institute, Japanese Foundation for Cancer Research, Tokyo, Japan
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5
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Abstract
The microtubule minus-end-directed motility of cytoplasmic dynein 1 (dynein), arguably the most complex and versatile cytoskeletal motor, is harnessed for diverse functions, such as long-range organelle transport in neuronal axons and spindle assembly in dividing cells. The versatility of dynein raises a number of intriguing questions, including how is dynein recruited to its diverse cargo, how is recruitment coupled to activation of the motor, how is motility regulated to meet different requirements for force production and how does dynein coordinate its activity with that of other microtubule-associated proteins (MAPs) present on the same cargo. Here, these questions will be discussed in the context of dynein at the kinetochore, the supramolecular protein structure that connects segregating chromosomes to spindle microtubules in dividing cells. As the first kinetochore-localized MAP described, dynein has intrigued cell biologists for more than three decades. The first part of this Review summarizes current knowledge about how kinetochore dynein contributes to efficient and accurate spindle assembly, and the second part describes the underlying molecular mechanisms and highlights emerging commonalities with dynein regulation at other subcellular sites.
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Affiliation(s)
- Reto Gassmann
- Instituto de Investigação e Inovação em Saúde - i3S, Universidade do Porto, 4200-135 Porto, Portugal.,Instituto de Biologia Molecular e Celular - IBMC, Universidade do Porto, 4200-135 Porto, Portugal
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6
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Janczyk PŁ, Żyłkiewicz E, De Hoyos H, West T, Matson DR, Choi WC, Young HMR, Derewenda ZS, Stukenberg PT. Aurora A phosphorylates Ndel1 to reduce the levels of Mad1 and NuMA at spindle poles. Mol Biol Cell 2023; 34:br1. [PMID: 36350697 PMCID: PMC9816647 DOI: 10.1091/mbc.e21-09-0438] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2021] [Revised: 10/26/2022] [Accepted: 10/31/2022] [Indexed: 11/11/2022] Open
Abstract
Dynein inactivates the spindle assembly checkpoint (SAC) by transporting checkpoint proteins away from kinetochores toward spindle poles in a process known as "stripping." We find that inhibition of Aurora A kinase, which is localized to spindle poles, enables the accumulation of the spindle checkpoint activator Mad1 at poles where it is normally absent. Aurora kinases phosphorylate the dynein activator NudE neurodevelopment protein 1 like 1 (Ndel1) on Ser285 and Mad1 accumulates at poles when Ndel1 is replaced by a nonphosphorylatable mutant in human cells. The pole focusing protein NuMA, transported to poles by dynein, also accumulates at poles in cells harboring a mutant Ndel1. Phosphorylation of Ndel1 on Ser285 is required for robust spindle checkpoint activity and regulates the poles of asters in Xenopus extracts. Our data suggest that dynein/SAC complexes that are generated at kinetochores and then transported directionally toward poles on microtubules are inhibited by Aurora A before they reach spindle poles. These data suggest that Aurora A generates a spatial signal at spindle poles that controls dynein transport and spindle function.
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Affiliation(s)
- Paweł Ł. Janczyk
- Department of Biochemistry and Molecular Genetics, University of Virginia School of Medicine, Charlottesville, VA 22903
- Department of Pathology, University of Virginia School of Medicine, Charlottesville, VA 22903
| | - Eliza Żyłkiewicz
- Department of Biochemistry and Molecular Genetics, University of Virginia School of Medicine, Charlottesville, VA 22903
| | - Henry De Hoyos
- Department of Biochemistry and Molecular Genetics, University of Virginia School of Medicine, Charlottesville, VA 22903
| | - Thomas West
- Department of Biochemistry and Molecular Genetics, University of Virginia School of Medicine, Charlottesville, VA 22903
| | - Daniel R. Matson
- Department of Biochemistry and Molecular Genetics, University of Virginia School of Medicine, Charlottesville, VA 22903
| | - Won-Chan Choi
- Department of Molecular Physiology and Biological Physics, University of Virginia School of Medicine, Charlottesville, VA 22903
| | - Heather M. Raimer Young
- Department of Biochemistry and Molecular Genetics, University of Virginia School of Medicine, Charlottesville, VA 22903
| | - Zygmunt S. Derewenda
- Department of Molecular Physiology and Biological Physics, University of Virginia School of Medicine, Charlottesville, VA 22903
| | - P. Todd Stukenberg
- Department of Biochemistry and Molecular Genetics, University of Virginia School of Medicine, Charlottesville, VA 22903
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7
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Song M, Dong S, Zhang X, Dai Y, Zhang X, Shen Y. A moderate static magnetic field promotes C. elegans longevity through cytochrome P450s. Sci Rep 2022; 12:16108. [PMID: 36167800 PMCID: PMC9515093 DOI: 10.1038/s41598-022-20647-0] [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: 01/28/2022] [Accepted: 09/16/2022] [Indexed: 11/15/2022] Open
Abstract
Ageing is co-regulated by genetic and environmental factors. Life on earth lives and evolves in a mild geomagnetic field. Yet, the biological effects of a moderate magnetic field on ageing and the underlying genetic mechanisms remain barely unknown. Here, we report that a moderate static magnetic field (SMF) extends the lifespan of Caenorhabditis elegans, a well-established model organism in ageing research. Consistently, the SMF-treated worms show improved motility and mitochondrial function when aged. We identified from the transcriptomic changes upon SMF treatment that the upregulation of three cytochrome P450 genes are required for SMF-induced longevity. Our findings thus reveal that proper SMF treatment could promote longevity through the well-conserved cytochrome P450 enzymes.
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Affiliation(s)
- Mengjiao Song
- State Key Laboratory of Cell Biology, Innovation Center for Cell Signaling Network, CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 320 Yueyang Rd., Shanghai, 200031, China
| | - Shiming Dong
- State Key Laboratory of Cell Biology, Innovation Center for Cell Signaling Network, CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 320 Yueyang Rd., Shanghai, 200031, China
| | - Xiangfei Zhang
- High Magnetic Field Laboratory, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei, China.,Science Island Branch of Graduate School, University of Science and Technology of China, Hefei, China
| | - Yumin Dai
- State Key Laboratory of Cell Biology, Innovation Center for Cell Signaling Network, CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 320 Yueyang Rd., Shanghai, 200031, China
| | - Xin Zhang
- High Magnetic Field Laboratory, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei, China.,Science Island Branch of Graduate School, University of Science and Technology of China, Hefei, China
| | - Yidong Shen
- State Key Laboratory of Cell Biology, Innovation Center for Cell Signaling Network, CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 320 Yueyang Rd., Shanghai, 200031, China.
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8
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SWAP, SWITCH, and STABILIZE: Mechanisms of Kinetochore–Microtubule Error Correction. Cells 2022; 11:cells11091462. [PMID: 35563768 PMCID: PMC9104000 DOI: 10.3390/cells11091462] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2022] [Revised: 04/20/2022] [Accepted: 04/21/2022] [Indexed: 11/17/2022] Open
Abstract
For correct chromosome segregation in mitosis, eukaryotic cells must establish chromosome biorientation where sister kinetochores attach to microtubules extending from opposite spindle poles. To establish biorientation, any aberrant kinetochore–microtubule interactions must be resolved in the process called error correction. For resolution of the aberrant interactions in error correction, kinetochore–microtubule interactions must be exchanged until biorientation is formed (the SWAP process). At initiation of biorientation, the state of weak kinetochore–microtubule interactions should be converted to the state of stable interactions (the SWITCH process)—the conundrum of this conversion is called the initiation problem of biorientation. Once biorientation is established, tension is applied on kinetochore–microtubule interactions, which stabilizes the interactions (the STABILIZE process). Aurora B kinase plays central roles in promoting error correction, and Mps1 kinase and Stu2 microtubule polymerase also play important roles. In this article, we review mechanisms of error correction by considering the SWAP, SWITCH, and STABILIZE processes. We mainly focus on mechanisms found in budding yeast, where only one microtubule attaches to a single kinetochore at biorientation, making the error correction mechanisms relatively simpler.
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9
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Doodhi H, Tanaka TU. Swap and stop - Kinetochores play error correction with microtubules: Mechanisms of kinetochore-microtubule error correction: Mechanisms of kinetochore-microtubule error correction. Bioessays 2022; 44:e2100246. [PMID: 35261042 PMCID: PMC9344824 DOI: 10.1002/bies.202100246] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2021] [Revised: 02/23/2022] [Accepted: 02/25/2022] [Indexed: 12/30/2022]
Abstract
Correct chromosome segregation in mitosis relies on chromosome biorientation, in which sister kinetochores attach to microtubules from opposite spindle poles prior to segregation. To establish biorientation, aberrant kinetochore–microtubule interactions must be resolved through the error correction process. During error correction, kinetochore–microtubule interactions are exchanged (swapped) if aberrant, but the exchange must stop when biorientation is established. In this article, we discuss recent findings in budding yeast, which have revealed fundamental molecular mechanisms promoting this “swap and stop” process for error correction. Where relevant, we also compare the findings in budding yeast with mechanisms in higher eukaryotes. Evidence suggests that Aurora B kinase differentially regulates kinetochore attachments to the microtubule end and its lateral side and switches relative strength of the two kinetochore–microtubule attachment modes, which drives the exchange of kinetochore–microtubule interactions to resolve aberrant interactions. However, Aurora B kinase, recruited to centromeres and inner kinetochores, cannot reach its targets at kinetochore–microtubule interface when tension causes kinetochore stretching, which stops the kinetochore–microtubule exchange once biorientation is established.
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Affiliation(s)
- Harinath Doodhi
- Centre for Gene Regulation and Expression, School of Life Sciences, University of Dundee, Dundee, UK
| | - Tomoyuki U Tanaka
- Centre for Gene Regulation and Expression, School of Life Sciences, University of Dundee, Dundee, UK
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10
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Zhang Y, Zhang X, Dai Y, Song M, Zhou Y, Zhou J, Yan X, Shen Y. The decrease of intraflagellar transport impairs sensory perception and metabolism in ageing. Nat Commun 2021; 12:1789. [PMID: 33741976 PMCID: PMC7979750 DOI: 10.1038/s41467-021-22065-8] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2020] [Accepted: 02/26/2021] [Indexed: 12/22/2022] Open
Abstract
Sensory perception and metabolic homeostasis are known to deteriorate with ageing, impairing the health of aged animals, while mechanisms underlying their deterioration remain poorly understood. The potential interplay between the declining sensory perception and the impaired metabolism during ageing is also barely explored. Here, we report that the intraflagellar transport (IFT) in the cilia of sensory neurons is impaired in the aged nematode Caenorhabditis elegans due to a daf-19/RFX-modulated decrease of IFT components. We find that the reduced IFT in sensory cilia thus impairs sensory perception with ageing. Moreover, we demonstrate that whereas the IFT-dependent decrease of sensory perception in aged worms has a mild impact on the insulin/IGF-1 signalling, it remarkably suppresses AMP-activated protein kinase (AMPK) signalling across tissues. We show that upregulating daf-19/RFX effectively enhances IFT, sensory perception, AMPK activity and autophagy, promoting metabolic homeostasis and longevity. Our study determines an ageing pathway causing IFT decay and sensory perception deterioration, which in turn disrupts metabolism and healthy ageing.
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Affiliation(s)
- Yincong Zhang
- State Key Laboratory of Cell Biology, Shanghai Institute of Biochemistry and Cell Biology, Center for Excellence in Molecular Cell Science, Chinese Academy of Sciences, Shanghai, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Xiaona Zhang
- State Key Laboratory of Cell Biology, Shanghai Institute of Biochemistry and Cell Biology, Center for Excellence in Molecular Cell Science, Chinese Academy of Sciences, Shanghai, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Yumin Dai
- State Key Laboratory of Cell Biology, Shanghai Institute of Biochemistry and Cell Biology, Center for Excellence in Molecular Cell Science, Chinese Academy of Sciences, Shanghai, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Mengjiao Song
- State Key Laboratory of Cell Biology, Shanghai Institute of Biochemistry and Cell Biology, Center for Excellence in Molecular Cell Science, Chinese Academy of Sciences, Shanghai, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Yifei Zhou
- State Key Laboratory of Cell Biology, Shanghai Institute of Biochemistry and Cell Biology, Center for Excellence in Molecular Cell Science, Chinese Academy of Sciences, Shanghai, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Jun Zhou
- Institute of Biomedical Sciences, College of Life Sciences, Key Laboratory of Animal Resistance Biology of Shandong Province, Collaborative Innovation Center of Cell Biology in Universities of Shandong, Shandong Normal University, Jinan, Shandong, China
- State Key Laboratory of Medicinal Chemical Biology, College of Life Sciences, Nankai University, Tianjin, China
| | - Xiumin Yan
- State Key Laboratory of Cell Biology, Shanghai Institute of Biochemistry and Cell Biology, Center for Excellence in Molecular Cell Science, Chinese Academy of Sciences, Shanghai, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Yidong Shen
- State Key Laboratory of Cell Biology, Shanghai Institute of Biochemistry and Cell Biology, Center for Excellence in Molecular Cell Science, Chinese Academy of Sciences, Shanghai, China.
- University of Chinese Academy of Sciences, Beijing, China.
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11
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Wooten M, Ranjan R, Chen X. Asymmetric Histone Inheritance in Asymmetrically Dividing Stem Cells. Trends Genet 2020; 36:30-43. [PMID: 31753528 PMCID: PMC6925335 DOI: 10.1016/j.tig.2019.10.004] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2019] [Revised: 09/21/2019] [Accepted: 10/15/2019] [Indexed: 12/26/2022]
Abstract
Epigenetic mechanisms play essential roles in determining distinct cell fates during the development of multicellular organisms. Histone proteins represent crucial epigenetic components that help specify cell identities. Previous work has demonstrated that during the asymmetric cell division of Drosophila male germline stem cells (GSCs), histones H3 and H4 are asymmetrically inherited, such that pre-existing (old) histones are segregated towards the self-renewing GSC whereas newly synthesized (new) histones are enriched towards the differentiating daughter cell. In order to further understand the molecular mechanisms underlying this striking phenomenon, two key questions must be answered: when and how old and new histones are differentially incorporated by sister chromatids, and how epigenetically distinct sister chromatids are specifically recognized and segregated. Here, we discuss recent advances in our understanding of the molecular mechanisms and cellular bases underlying these fundamental and important biological processes responsible for generating two distinct cells through one cell division.
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Affiliation(s)
- Matthew Wooten
- Department of Biology, The Johns Hopkins University, Baltimore, MD 21218, USA
| | - Rajesh Ranjan
- Department of Biology, The Johns Hopkins University, Baltimore, MD 21218, USA
| | - Xin Chen
- Department of Biology, The Johns Hopkins University, Baltimore, MD 21218, USA.
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12
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Xu Y, He Z, Song M, Zhou Y, Shen Y. A microRNA switch controls dietary restriction-induced longevity through Wnt signaling. EMBO Rep 2019; 20:embr.201846888. [PMID: 30872315 DOI: 10.15252/embr.201846888] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2018] [Revised: 01/31/2019] [Accepted: 02/12/2019] [Indexed: 12/29/2022] Open
Abstract
Dietary restriction (DR) is known to have a potent and conserved longevity effect, yet its underlying molecular mechanisms remain elusive. DR modulates signaling pathways in response to nutrient status, a process that also regulates animal development. Here, we show that the suppression of Wnt signaling, a key pathway controlling development, is required for DR-induced longevity in Caenorhabditis elegans We find that DR induces the expression of mir-235, which inhibits cwn-1/WNT4 expression by binding to the 3'-UTR The "switch-on" of mir-235 by DR occurs at the onset of adulthood, thereby minimizing potential disruptions in development. Our results therefore implicate that DR controls the adult lifespan by using a temporal microRNA switch to modulate Wnt signaling.
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Affiliation(s)
- Yunpeng Xu
- State Key Laboratory of Cell Biology, Innovation Center for Cell Signaling Network, CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences-University of Chinese Academy of Sciences, Shanghai, China
| | - Zhidong He
- State Key Laboratory of Cell Biology, Innovation Center for Cell Signaling Network, CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences-University of Chinese Academy of Sciences, Shanghai, China
| | - Mengjiao Song
- State Key Laboratory of Cell Biology, Innovation Center for Cell Signaling Network, CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences-University of Chinese Academy of Sciences, Shanghai, China
| | - Yifei Zhou
- State Key Laboratory of Cell Biology, Innovation Center for Cell Signaling Network, CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences-University of Chinese Academy of Sciences, Shanghai, China
| | - Yidong Shen
- State Key Laboratory of Cell Biology, Innovation Center for Cell Signaling Network, CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences-University of Chinese Academy of Sciences, Shanghai, China
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13
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Wynne CL, Vallee RB. Cdk1 phosphorylation of the dynein adapter Nde1 controls cargo binding from G2 to anaphase. J Cell Biol 2018; 217:3019-3029. [PMID: 29930206 PMCID: PMC6122996 DOI: 10.1083/jcb.201707081] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2017] [Revised: 04/06/2018] [Accepted: 05/23/2018] [Indexed: 12/28/2022] Open
Abstract
Cytoplasmic dynein is involved in diverse cell cycle-dependent functions regulated by several accessory factors, including Nde1 and Ndel1. Little is known about the role of these proteins in dynein cargo binding, and less is known about their cell cycle--dependent dynein regulation. Using Nde1 RNAi, mutant cDNAs, and a phosphorylation site-specific antibody, we found a specific association of phospho-Nde1 with the late G2-M nuclear envelope and prophase to anaphase kinetochores, comparable to the pattern for the Nde1 interactor CENP-F. Phosphomutant-Nde1 associated only with prometaphase kinetochores and showed weaker CENP-F binding in in vitro assays. Nde1 RNAi caused severe delays in mitotic progression, which were substantially rescued by both phosphomimetic and phosphomutant Nde1. Expression of a dynein-binding-deficient Nde1 mutant reduced kinetochore dynein by half, indicating a major role for Nde1 in kinetochore dynein recruitment. These results establish CENP-F as the first well-characterized Nde1 cargo protein, and reveal phosphorylation control of Nde1 cargo binding throughout a substantial fraction of the cell cycle.
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Affiliation(s)
- Caitlin L Wynne
- Pathology and Cell Biology, Columbia University, New York, NY
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14
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Mechanisms of Chromosome Congression during Mitosis. BIOLOGY 2017; 6:biology6010013. [PMID: 28218637 PMCID: PMC5372006 DOI: 10.3390/biology6010013] [Citation(s) in RCA: 93] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/01/2016] [Revised: 01/07/2017] [Accepted: 01/28/2017] [Indexed: 12/13/2022]
Abstract
Chromosome congression during prometaphase culminates with the establishment of a metaphase plate, a hallmark of mitosis in metazoans. Classical views resulting from more than 100 years of research on this topic have attempted to explain chromosome congression based on the balance between opposing pulling and/or pushing forces that reach an equilibrium near the spindle equator. However, in mammalian cells, chromosome bi-orientation and force balance at kinetochores are not required for chromosome congression, whereas the mechanisms of chromosome congression are not necessarily involved in the maintenance of chromosome alignment after congression. Thus, chromosome congression and maintenance of alignment are determined by different principles. Moreover, it is now clear that not all chromosomes use the same mechanism for congressing to the spindle equator. Those chromosomes that are favorably positioned between both poles when the nuclear envelope breaks down use the so-called "direct congression" pathway in which chromosomes align after bi-orientation and the establishment of end-on kinetochore-microtubule attachments. This favors the balanced action of kinetochore pulling forces and polar ejection forces along chromosome arms that drive chromosome oscillatory movements during and after congression. The other pathway, which we call "peripheral congression", is independent of end-on kinetochore microtubule-attachments and relies on the dominant and coordinated action of the kinetochore motors Dynein and Centromere Protein E (CENP-E) that mediate the lateral transport of peripheral chromosomes along microtubules, first towards the poles and subsequently towards the equator. How the opposite polarities of kinetochore motors are regulated in space and time to drive congression of peripheral chromosomes only now starts to be understood. This appears to be regulated by position-dependent phosphorylation of both Dynein and CENP-E and by spindle microtubule diversity by means of tubulin post-translational modifications. This so-called "tubulin code" might work as a navigation system that selectively guides kinetochore motors with opposite polarities along specific spindle microtubule populations, ultimately leading to the congression of peripheral chromosomes. We propose an integrated model of chromosome congression in mammalian cells that depends essentially on the following parameters: (1) chromosome position relative to the spindle poles after nuclear envelope breakdown; (2) establishment of stable end-on kinetochore-microtubule attachments and bi-orientation; (3) coordination between kinetochore- and arm-associated motors; and (4) spatial signatures associated with post-translational modifications of specific spindle microtubule populations. The physiological consequences of abnormal chromosome congression, as well as the therapeutic potential of inhibiting chromosome congression are also discussed.
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15
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Li C, Xue C, Yang Q, Low BC, Liou YC. NuSAP governs chromosome oscillation by facilitating the Kid-generated polar ejection force. Nat Commun 2016; 7:10597. [PMID: 26839278 PMCID: PMC4742958 DOI: 10.1038/ncomms10597] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2015] [Accepted: 01/04/2016] [Indexed: 12/17/2022] Open
Abstract
In vertebrate cells, chromosomes oscillate to align precisely during metaphase. NuSAP, a microtubule-associated protein, plays a critical role in stabilizing spindle microtubules. In this study, we utilize 3D time-lapse live-cell imaging to monitor the role of NuSAP in chromosome oscillation and identify NuSAP as a novel regulator of the chromokinesin, Kid. Depletion of NuSAP significantly suppresses the amplitude and velocity of chromosome oscillation. We analyse the effects of NuSAP and Kid depletion in monopolar and bipolar cells with or without kinetochore microtubule depletion. Twelve postulated conditions are deciphered to reveal the contribution of NuSAP to the polar force generated at kinetochore microtubules and to the regulation of the polar ejection force generated by Kid, thus revealing a pivotal role of NuSAP in chromosome oscillation. During metaphase, alignment of chromosomes is facilitated by oscillations driven by the chromokinesin Kid. Here Li et al. show that the microtubule-associated protein NuSAP is a novel regulator of Kid, regulating the amplitude and velocity of chromosome oscillation.
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Affiliation(s)
- Chenyu Li
- Department of Biological Sciences, Faculty of Science, National University of Singapore, 14 Science Drive 4, Singapore 117543, Republic of Singapore
| | - Chenyi Xue
- Cardiovascular Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA
| | - Qiaoyun Yang
- Department of Biological Sciences, Faculty of Science, National University of Singapore, 14 Science Drive 4, Singapore 117543, Republic of Singapore
| | - Boon Chuan Low
- Department of Biological Sciences, Faculty of Science, National University of Singapore, 14 Science Drive 4, Singapore 117543, Republic of Singapore.,Mechanobiology Institute, National University of Singapore, Singapore 117411, Republic of Singapore
| | - Yih-Cherng Liou
- Department of Biological Sciences, Faculty of Science, National University of Singapore, 14 Science Drive 4, Singapore 117543, Republic of Singapore.,Graduate School for Integrative Sciences and Engineering, National University of Singapore, Singapore 117573, Republic of Singapore
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Wan Y, Zheng X, Chen H, Guo Y, Jiang H, He X, Zhu X, Zheng Y. Splicing function of mitotic regulators links R-loop-mediated DNA damage to tumor cell killing. ACTA ACUST UNITED AC 2015; 209:235-46. [PMID: 25918225 PMCID: PMC4411280 DOI: 10.1083/jcb.201409073] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Mitotic regulators BuGZ and Bub3 play a critical role in RNA splicing during interphase, and disruption of this function leads to R-loop formation, DNA damage, and p53 activation. Although studies suggest that perturbing mitotic progression leads to DNA damage and p53 activation, which in turn lead to either cell apoptosis or senescence, it remains unclear how mitotic defects trigger p53 activation. We show that BuGZ and Bub3, which are two mitotic regulators localized in the interphase nucleus, interact with the splicing machinery and are required for pre-mRNA splicing. Similar to inhibition of RNA splicing by pladienolide B, depletion of either BuGZ or Bub3 led to increased formation of RNA–DNA hybrids (R-loops), which led to DNA damage and p53 activation in both human tumor cells and primary cells. Thus, R-loop–mediated DNA damage and p53 activation offer a mechanistic explanation for apoptosis of cancer cells and senescence of primary cells upon disruption of the dual-function mitotic regulators. This demonstrates the importance of understanding the full range of functions of mitotic regulators to develop antitumor drugs.
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Affiliation(s)
- Yihan Wan
- State Key Laboratory of Cell Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200031, China Department of Embryology, Carnegie Institution for Science, Baltimore, MD 21218
| | - Xiaobin Zheng
- Department of Embryology, Carnegie Institution for Science, Baltimore, MD 21218
| | - Haiyang Chen
- Department of Embryology, Carnegie Institution for Science, Baltimore, MD 21218
| | - Yuxuan Guo
- Department of Embryology, Carnegie Institution for Science, Baltimore, MD 21218
| | - Hao Jiang
- State Key Laboratory of Cell Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200031, China Department of Embryology, Carnegie Institution for Science, Baltimore, MD 21218
| | - Xiaonan He
- State Key Laboratory of Cell Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200031, China
| | - Xueliang Zhu
- State Key Laboratory of Cell Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200031, China
| | - Yixian Zheng
- Department of Embryology, Carnegie Institution for Science, Baltimore, MD 21218
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17
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Moudgil DK, Westcott N, Famulski JK, Patel K, Macdonald D, Hang H, Chan GKT. A novel role of farnesylation in targeting a mitotic checkpoint protein, human Spindly, to kinetochores. ACTA ACUST UNITED AC 2015; 208:881-96. [PMID: 25825516 PMCID: PMC4384735 DOI: 10.1083/jcb.201412085] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The mitotic checkpoint protein Spindly is farnesylated in vivo and this modification is required for its interaction with the RZZ complex and its localization to kinetochores. Kinetochore (KT) localization of mitotic checkpoint proteins is essential for their function during mitosis. hSpindly KT localization is dependent on the RZZ complex and hSpindly recruits the dynein–dynactin complex to KTs during mitosis, but the mechanism of hSpindly KT recruitment is unknown. Through domain-mapping studies we characterized the KT localization domain of hSpindly and discovered it undergoes farnesylation at the C-terminal cysteine residue. The N-terminal 293 residues of hSpindly are dispensable for its KT localization. Inhibition of farnesylation using a farnesyl transferase inhibitor (FTI) abrogated hSpindly KT localization without affecting RZZ complex, CENP-E, and CENP-F KT localization. We showed that hSpindly is farnesylated in vivo and farnesylation is essential for its interaction with the RZZ complex and hence KT localization. FTI treatment and hSpindly knockdown displayed the same mitotic phenotypes, indicating that hSpindly is a key FTI target in mitosis. Our data show a novel role of lipidation in targeting a checkpoint protein to KTs through protein–protein interaction.
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Affiliation(s)
| | - Nathan Westcott
- Laboratory of Chemical Biology and Microbial Pathogenesis, Rockefeller University, New York, NY 10065
| | - Jakub K Famulski
- Department of Oncology, University of Alberta, Edmonton, Alberta, Canada T6G 1Z2
| | - Kinjal Patel
- Department of Oncology, University of Alberta, Edmonton, Alberta, Canada T6G 1Z2
| | - Dawn Macdonald
- Department of Oncology, University of Alberta, Edmonton, Alberta, Canada T6G 1Z2
| | - Howard Hang
- Laboratory of Chemical Biology and Microbial Pathogenesis, Rockefeller University, New York, NY 10065
| | - Gordon K T Chan
- Department of Oncology, University of Alberta, Edmonton, Alberta, Canada T6G 1Z2
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18
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Ferreira JG, Pereira AL, Maiato H. Microtubule plus-end tracking proteins and their roles in cell division. INTERNATIONAL REVIEW OF CELL AND MOLECULAR BIOLOGY 2014; 309:59-140. [PMID: 24529722 DOI: 10.1016/b978-0-12-800255-1.00002-8] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Microtubules are cellular components that are required for a variety of essential processes such as cell motility, mitosis, and intracellular transport. This is possible because of the inherent dynamic properties of microtubules. Many of these properties are tightly regulated by a number of microtubule plus-end-binding proteins or +TIPs. These proteins recognize the distal end of microtubules and are thus in the right context to control microtubule dynamics. In this review, we address how microtubule dynamics are regulated by different +TIP families, focusing on how functionally diverse +TIPs spatially and temporally regulate microtubule dynamics during animal cell division.
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Affiliation(s)
- Jorge G Ferreira
- Chromosome Instability & Dynamics Laboratory, Instituto de Biologia Molecular e Celular, University of Porto, Porto, Portugal; Cell Division Unit, Department of Experimental Biology, University of Porto, Porto, Portugal
| | - Ana L Pereira
- Chromosome Instability & Dynamics Laboratory, Instituto de Biologia Molecular e Celular, University of Porto, Porto, Portugal
| | - Helder Maiato
- Chromosome Instability & Dynamics Laboratory, Instituto de Biologia Molecular e Celular, University of Porto, Porto, Portugal; Cell Division Unit, Department of Experimental Biology, University of Porto, Porto, Portugal.
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19
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Raaijmakers JA, Medema RH. Function and regulation of dynein in mitotic chromosome segregation. Chromosoma 2014; 123:407-22. [PMID: 24871939 DOI: 10.1007/s00412-014-0468-7] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2014] [Revised: 05/08/2014] [Accepted: 05/09/2014] [Indexed: 12/23/2022]
Abstract
Cytoplasmic dynein is a large minus-end-directed microtubule motor complex, involved in many different cellular processes including intracellular trafficking, organelle positioning, and microtubule organization. Furthermore, dynein plays essential roles during cell division where it is implicated in multiple processes including centrosome separation, chromosome movements, spindle organization, spindle positioning, and mitotic checkpoint silencing. How is a single motor able to fulfill this large array of functions and how are these activities temporally and spatially regulated? The answer lies in the unique composition of the dynein motor and in the interactions it makes with multiple regulatory proteins that define the time and place where dynein becomes active. Here, we will focus on the different mitotic processes that dynein is involved in, and how its regulatory proteins act to support dynein. Although dynein is highly conserved amongst eukaryotes (with the exception of plants), there is significant variability in the cellular processes that depend on dynein in different species. In this review, we concentrate on the functions of cytoplasmic dynein in mammals but will also refer to data obtained in other model organisms that have contributed to our understanding of dynein function in higher eukaryotes.
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Affiliation(s)
- J A Raaijmakers
- Department of Cell Biology and Cancer Genomics Center, The Netherlands Cancer Institute, Plesmanlaan 121, 1066 CX, Amsterdam, Netherlands
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20
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Wang Y, Jin F, Higgins R, McKnight K. The current view for the silencing of the spindle assembly checkpoint. Cell Cycle 2014; 13:1694-701. [PMID: 24776751 DOI: 10.4161/cc.29027] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Chromosome bipolar attachment is achieved when sister kinetochores are attached by microtubules emanating from opposite spindle poles, and this process is essential for faithful chromosome segregation during anaphase. A fundamental question in cell biology is how cells ensure that chromosome segregation only occurs after bipolar attachment. It is well documented that unattached kinetochores activate the spindle assembly checkpoint (SAC) to delay chromosome segregation. Therefore, the silencing of the SAC is thought to trigger anaphase onset, but how correct chromosome attachment is coupled with SAC silencing and the subsequent anaphase onset is poorly understood. The establishment of chromosome bipolar attachment not only results in the occupancy of kinetochores by microtubules but also applies tension on sister kinetochores. A long-standing debate is whether the kinetochore attachment (occupancy) or the tension silences the SAC. Recent work in budding yeast reveals the SAC silencing network SSN that prevents SAC silencing prior to tension generation at kinetochores. Therefore, this signaling pathway ensures that SAC silencing and the subsequent anaphase onset occur only after chromosome bipolar attachment applies tension on chromosomes. This review will summarize the recent advances in the understanding of the SAC silencing process.
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Affiliation(s)
- Yanchang Wang
- Department of Biomedical Sciences; College of Medicine; Florida State University; Tallahassee, FL USA
| | - Fengzhi Jin
- Department of Biomedical Sciences; College of Medicine; Florida State University; Tallahassee, FL USA
| | - Ryan Higgins
- Department of Biomedical Sciences; College of Medicine; Florida State University; Tallahassee, FL USA
| | - Kelly McKnight
- Department of Biomedical Sciences; College of Medicine; Florida State University; Tallahassee, FL USA
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21
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Varma D, Wan X, Cheerambathur D, Gassmann R, Suzuki A, Lawrimore J, Desai A, Salmon ED. Spindle assembly checkpoint proteins are positioned close to core microtubule attachment sites at kinetochores. ACTA ACUST UNITED AC 2013; 202:735-46. [PMID: 23979716 PMCID: PMC3760617 DOI: 10.1083/jcb.201304197] [Citation(s) in RCA: 56] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
Depletion analyses and nanometer-scale mapping of spindle assembly checkpoint proteins reveal how these proteins are integrated within the substructure of the kinetochore. Spindle assembly checkpoint proteins have been thought to reside in the peripheral corona region of the kinetochore, distal to microtubule attachment sites at the outer plate. However, recent biochemical evidence indicates that checkpoint proteins are closely linked to the core kinetochore microtubule attachment site comprised of the Knl1–Mis12–Ndc80 (KMN) complexes/KMN network. In this paper, we show that the Knl1–Zwint1 complex is required to recruit the Rod–Zwilch–Zw10 (RZZ) and Mad1–Mad2 complexes to the outer kinetochore. Consistent with this, nanometer-scale mapping indicates that RZZ, Mad1–Mad2, and the C terminus of the dynein recruitment factor Spindly are closely juxtaposed with the KMN network in metaphase cells when their dissociation is blocked and the checkpoint is active. In contrast, the N terminus of Spindly is ∼75 nm outside the calponin homology domain of the Ndc80 complex. These results reveal how checkpoint proteins are integrated within the substructure of the kinetochore and will aid in understanding the coordination of microtubule attachment and checkpoint signaling during chromosome segregation.
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Affiliation(s)
- Dileep Varma
- Department of Biology, The University of North Carolina-Chapel Hill, Chapel Hill, NC 27599, USA.
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22
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Fiore M, Mattiuzzo M, Mancuso G, Totta P, Degrassi F. The pesticide dichlorvos disrupts mitotic division by delocalizing the kinesin Kif2a from centrosomes. ENVIRONMENTAL AND MOLECULAR MUTAGENESIS 2013; 54:250-60. [PMID: 23532982 DOI: 10.1002/em.21769] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/29/2012] [Revised: 02/07/2013] [Accepted: 02/07/2013] [Indexed: 05/25/2023]
Abstract
The molecular mechanism(s) mediating long-term adverse effects of dichlorvos, a widely used insecticide, are still unclear. Our work uncovered a new cellular effect of dichlorvos in cultured human cells, i.e. its capacity to induce extremely aberrant mitotic spindles with monopolar microtubule arrays that were associated with hypercondensed chromosomes and pyknotic chromatin masses. Monopolar spindles produced by dichlorvos treatment were characterized by the delocalization of the depolymerizing kinesin Kif2a from spindle poles. Dichlorvos-induced spindle monopolarity could be reversed by promoting microtubule stabilization through chemical treatment or by inhibiting the depolymerizing function of the kinesin MCAK at kinetochores. These findings demonstrate that dichlorvos inhibits the depolymerizing activity of Kif2a at centrosomes and thereby disrupts the balance of opposing centrosomal and kinetochore forces controlling spindle bipolarity during prometaphase. Dichlorvos-induced defects in spindle bipolarity may be responsible for the previously reported induction of aneuploidy by this chemical. Collectively, these results indicate that environmental chemicals, such as dichlorvos, may promote chromosome instability by interfering with the cell division machinery.
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Affiliation(s)
- Mario Fiore
- Institute of Molecular Biology and Pathology, CNR, National Research Council of Italy, c/o Sapienza University, Rome, Italy
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23
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Guo Y, Kim C, Mao Y. New insights into the mechanism for chromosome alignment in metaphase. INTERNATIONAL REVIEW OF CELL AND MOLECULAR BIOLOGY 2013; 303:237-62. [PMID: 23445812 DOI: 10.1016/b978-0-12-407697-6.00006-4] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
During mitosis, duplicated sister chromatids are properly aligned at the metaphase plate of the mitotic spindle before being segregated into two daughter cells. This requires a complex process to ensure proper interactions between chromosomes and spindle microtubules. The kinetochore, the proteinaceous complex assembled at the centromere region on each chromosome, serves as the microtubule attachment site and powers chromosome movement in mitosis. Numerous proteins/protein complexes have been implicated in the connection between kinetochores and dynamic microtubules. Recent studies have advanced our understanding on the nature of the interface between kinetochores and microtubule plus ends in promoting and maintaining their stable attachment. These efforts have demonstrated the importance of this process to ensure accurate chromosome segregation, an issue which has great significance for understanding and controlling abnormal chromosome segregation (aneuploidy) in human genetic diseases and in cancer progression.
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Affiliation(s)
- Yige Guo
- Department of Pathology and Cell Biology, Columbia University College of Physicians and Surgeons, NY, USA
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24
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Shen Y, Wollam J, Magner D, Karalay O, Antebi A. A steroid receptor-microRNA switch regulates life span in response to signals from the gonad. Science 2012; 338:1472-6. [PMID: 23239738 PMCID: PMC3909774 DOI: 10.1126/science.1228967] [Citation(s) in RCA: 81] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Although the gonad primarily functions in procreation, it also affects animal life span. Here, we show that removal of the Caenorhabditis elegans germ line triggers a switch in the regulatory state of the organism to promote longevity, co-opting components involved in larval developmental timing circuits. These components include the DAF-12 steroid receptor, which is involved in the larval stage two-to-stage three (L2-L3) transition and up-regulates members of the let-7 microRNA (miRNA) family. The miRNAs target an early larval nuclear factor lin-14 and akt-1/kinase, thereby stimulating DAF-16/FOXO signaling to extend life. Our studies suggest that metazoan life span is coupled to the gonad through elements of a developmental timer.
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Affiliation(s)
- Yidong Shen
- Max Planck Institute for Biology of Ageing, Gleueler Str. 50a, D-50931 Cologne, Germany
- Department of Molecular and Cellular Biology, Huffington Center on Aging, Baylor College of Medicine, Houston, Texas 77030, USA
| | - Joshua Wollam
- Max Planck Institute for Biology of Ageing, Gleueler Str. 50a, D-50931 Cologne, Germany
- Department of Molecular and Cellular Biology, Huffington Center on Aging, Baylor College of Medicine, Houston, Texas 77030, USA
| | - Daniel Magner
- Max Planck Institute for Biology of Ageing, Gleueler Str. 50a, D-50931 Cologne, Germany
- Department of Molecular and Cellular Biology, Huffington Center on Aging, Baylor College of Medicine, Houston, Texas 77030, USA
| | - Oezlem Karalay
- Max Planck Institute for Biology of Ageing, Gleueler Str. 50a, D-50931 Cologne, Germany
| | - Adam Antebi
- Max Planck Institute for Biology of Ageing, Gleueler Str. 50a, D-50931 Cologne, Germany
- Department of Molecular and Cellular Biology, Huffington Center on Aging, Baylor College of Medicine, Houston, Texas 77030, USA
- Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD), University of Cologne, D-50674 Cologne, Germany
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25
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Tamura N, Draviam VM. Microtubule plus-ends within a mitotic cell are 'moving platforms' with anchoring, signalling and force-coupling roles. Open Biol 2012; 2:120132. [PMID: 23226599 PMCID: PMC3513837 DOI: 10.1098/rsob.120132] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2012] [Accepted: 11/01/2012] [Indexed: 12/21/2022] Open
Abstract
The microtubule polymer grows and shrinks predominantly from one of its ends called the 'plus-end'. Plus-end regulation during interphase is well understood. However, mitotic regulation of plus-ends is only beginning to be understood in mammalian cells. During mitosis, the plus-ends are tethered to specialized microtubule capture sites. At these sites, plus-end-binding proteins are loaded and unloaded in a regulated fashion. Proper tethering of plus-ends to specialized sites is important so that the microtubule is able to translate its growth and shrinkage into pushing and pulling forces that move bulky subcellular structures. We discuss recent advances on how mitotic plus-ends are tethered to distinct subcellular sites and how plus-end-bound proteins can modulate the forces that move subcellular structures. Using end binding 1 (EB1) as a prototype plus-end-binding protein, we highlight the complex network of plus-end-binding proteins and their regulation through phosphorylation. Finally, we develop a speculative 'moving platform' model that illustrates the plus-end's role in distinguishing correct versus incorrect microtubule interactions.
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Affiliation(s)
| | - Viji M. Draviam
- Department of Genetics, University of Cambridge, Downing Site, Downing Street, Cambridge CB2 3EH, UK
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Silió V, Redondo-Muñoz J, Carrera AC. Phosphoinositide 3-kinase β regulates chromosome segregation in mitosis. Mol Biol Cell 2012; 23:4526-42. [PMID: 23051731 PMCID: PMC3510015 DOI: 10.1091/mbc.e12-05-0371] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
The phosphoinositide 3-kinase (PI3K) pathway is mutated in approximately half of tumors; it is therefore important to define its functions. This study shows that PI3Kα activity regulates mitotic entry and spindle orientation; in contrast, PI3Kβ controls dynein/dynactin and Aurora B activation at kinetochores and, in turn, chromosome segregation. Class IA phosphoinositide 3-kinases (PI3K) are enzymes composed of a p85 regulatory and a p110 catalytic subunit that control formation of 3-poly-phosphoinositides (PIP3). The PI3K pathway regulates cell survival, migration, and division, and is mutated in approximately half of human tumors. For this reason, it is important to define the function of the ubiquitous PI3K subunits, p110α and p110β. Whereas p110α is activated at G1-phase entry and promotes protein synthesis and gene expression, p110β activity peaks in S phase and regulates DNA synthesis. PI3K activity also increases at the onset of mitosis, but the isoform activated is unknown; we have examined p110α and p110β function in mitosis. p110α was activated at mitosis entry and regulated early mitotic events, such as PIP3 generation, prometaphase progression, and spindle orientation. In contrast, p110β was activated near metaphase and controlled dynein/dynactin and Aurora B activities in kinetochores, chromosome segregation, and optimal function of the spindle checkpoint. These results reveal a p110β function in preserving genomic stability during mitosis.
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Affiliation(s)
- Virginia Silió
- Department of Immunology and Oncology, Centro Nacional de Biotecnología/CSIC, Campus Universidad Autónoma de Madrid, Cantoblanco, Madrid E-28049, Spain
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27
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Connecting up and clearing out: how kinetochore attachment silences the spindle assembly checkpoint. Chromosoma 2012; 121:509-25. [DOI: 10.1007/s00412-012-0378-5] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2012] [Revised: 06/14/2012] [Accepted: 06/18/2012] [Indexed: 02/06/2023]
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Abstract
Mitosis is the process by which eukaryotic cells organize and segregate their chromosomes in preparation for cell division. It is accomplished by a cellular machine composed largely of microtubules (MTs) and their associated proteins. This article reviews literature on mitosis from a biophysical point of view, drawing attention to the assembly and motility processes required to do this complex job with precision. Work from both the recent and the older literature is integrated into a description of relevant biological events and the experiments that probe their mechanisms. Theoretical work on specific subprocesses is also reviewed. Our goal is to provide a document that will expose biophysicists to the fascination of this quite amazing process and provide them with a good background from which they can pursue their own research interests in the subject.
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Abstract
The mechanisms that move chromatids poleward during anaphase A have fascinated researchers for decades. There is now growing evidence that this movement is tightly linked to the active depolymerization of both ends of kinetochore-associated microtubules, a mechanism we refer to as "Pacman-Flux." Contemporary data suggest that this is catalyzed by the integration of multiple enzymatic activities including (1) microtubule-end depolymerases housed at the pole or kinetochore, (2) microtubule-severing enzymes used to uncap the ends of kinetochore-associated microtubules, and (3) molecular motors which drive tubulins towards the pole or into kinetochores.
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30
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Kasuboski JM, Bader JR, Vaughan PS, Tauhata SBF, Winding M, Morrissey MA, Joyce MV, Boggess W, Vos L, Chan GK, Hinchcliffe EH, Vaughan KT. Zwint-1 is a novel Aurora B substrate required for the assembly of a dynein-binding platform on kinetochores. Mol Biol Cell 2011; 22:3318-30. [PMID: 21775627 PMCID: PMC3172258 DOI: 10.1091/mbc.e11-03-0213] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
Aurora B (AurB) is a mitotic kinase responsible for multiple aspects of mitotic progression, including assembly of the outer kinetochore. Cytoplasmic dynein is an abundant kinetochore protein whose recruitment to kinetochores requires phosphorylation. To assess whether AurB regulates recruitment of dynein to kinetochores, we inhibited AurB using ZM447439 or a kinase-dead AurB construct. Inhibition of AurB reduced accumulation of dynein at kinetochores substantially; however, this reflected a loss of dynein-associated proteins rather than a defect in dynein phosphorylation. We determined that AurB inhibition affected recruitment of the ROD, ZW10, zwilch (RZZ) complex to kinetochores but not zwint-1 or more-proximal kinetochore proteins. AurB phosphorylated zwint-1 but not ZW10 in vitro, and three novel phosphorylation sites were identified by tandem mass spectrometry analysis. Expression of a triple-Ala zwint-1 mutant blocked kinetochore assembly of RZZ-dependent proteins and induced defects in chromosome movement during prometaphase. Expression of a triple-Glu zwint-1 mutant rendered cells resistant to AurB inhibition during prometaphase. However, cells expressing the triple-Glu mutant failed to satisfy the spindle assembly checkpoint (SAC) at metaphase because poleward streaming of dynein/dynactin/RZZ was inhibited. These studies identify zwint-1 as a novel AurB substrate required for kinetochore assembly and for proper SAC silencing at metaphase.
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Affiliation(s)
- James M Kasuboski
- Department of Biological Sciences, University of Notre Dame, Notre Dame, IN 46556, USA
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The Cik1/Kar3 motor complex is required for the proper kinetochore-microtubule interaction after stressful DNA replication. Genetics 2010; 187:397-407. [PMID: 21135072 DOI: 10.1534/genetics.110.125468] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
In budding yeast Saccharomyces cerevisiae, kinetochores are attached by microtubules during most of the cell cycle, but the duplication of centromeric DNA disassembles kinetochores, which results in a brief dissociation of chromosomes from microtubules. Kinetochore assembly is delayed in the presence of hydroxyurea, a DNA synthesis inhibitor, presumably due to the longer time required for centromeric DNA duplication. Some kinetochore mutants are sensitive to stressful DNA replication as these kinetochore proteins become essential for the establishment of the kinetochore-microtubule interaction after treatment with hydroxyurea. To identify more genes required for the efficient kinetochore-microtubule interaction under stressful DNA replication conditions, we carried out a genome-wide screen for yeast mutants sensitive to hydroxyurea. From this screen, cik1 and kar3 mutants were isolated. Kar3 is the minus-end-directed motor protein; Cik1 binds to Kar3 and is required for its motor function. After exposure to hydroxyurea, cik1 and kar3 mutant cells exhibit normal DNA synthesis kinetics, but they display a significant anaphase entry delay. Our results indicate that cik1 cells exhibit a defect in the establishment of chromosome bipolar attachment in the presence of hydroxyurea. Since Kar3 has been shown to drive the poleward chromosome movement along microtubules, our data support the possibility that this chromosome movement promotes chromosome bipolar attachment after stressful DNA replication.
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Kinetochore-microtubule interactions: steps towards bi-orientation. EMBO J 2010; 29:4070-82. [PMID: 21102558 DOI: 10.1038/emboj.2010.294] [Citation(s) in RCA: 101] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2010] [Accepted: 10/29/2010] [Indexed: 11/08/2022] Open
Abstract
Eukaryotic cells segregate their chromosomes accurately to opposite poles during mitosis, which is necessary for maintenance of their genetic integrity. This process mainly relies on the forces generated by kinetochore-microtubule (KT-MT) attachment. During prometaphase, the KT initially interacts with a single MT extending from a spindle pole and then moves towards a spindle pole. Subsequently, MTs from the other spindle pole also interact with the KT. Eventually, one sister KT becomes attached to MTs from one pole while the other sister to those from the other pole (sister KT bi-orientation). If sister KTs interact with MTs with aberrant orientation, this must be corrected to attain proper bi-orientation (error correction) before the anaphase is initiated. Here, I discuss how KTs initially interact with MTs and how this interaction develops into bi-orientation; both processes are fundamentally crucial for proper chromosome segregation in the subsequent anaphase.
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Civril F, Wehenkel A, Giorgi FM, Santaguida S, Di Fonzo A, Grigorean G, Ciccarelli FD, Musacchio A. Structural analysis of the RZZ complex reveals common ancestry with multisubunit vesicle tethering machinery. Structure 2010; 18:616-26. [PMID: 20462495 DOI: 10.1016/j.str.2010.02.014] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2009] [Revised: 01/22/2010] [Accepted: 02/19/2010] [Indexed: 01/31/2023]
Abstract
The RZZ complex recruits dynein to kinetochores. We investigated structure, topology, and interactions of the RZZ subunits (ROD, ZWILCH, and ZW10) in vitro, in vivo, and in silico. We identify neuroblastoma-amplified gene (NAG), a ZW10 binder, as a ROD homolog. ROD and NAG contain an N-terminal beta propeller followed by an alpha solenoid, which is the architecture of certain nucleoporins and vesicle coat subunits, suggesting a distant evolutionary relationship. ZW10 binding to ROD and NAG is mutually exclusive. The resulting ZW10 complexes (RZZ and NRZ) respectively contain ZWILCH and RINT1 as additional subunits. The X-ray structure of ZWILCH, the first for an RZZ subunit, reveals a novel fold distinct from RINT1's. The evolutionarily conserved NRZ likely acts as a tethering complex for retrograde trafficking of COPI vesicles from the Golgi to the endoplasmic reticulum. The RZZ, limited to metazoans, probably evolved from the NRZ, exploiting the dynein-binding capacity of ZW10 to direct dynein to kinetochores.
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Affiliation(s)
- Filiz Civril
- Department of Experimental Oncology, European Institute of Oncology, Via Adamello 16, I-20139 Milan, Italy
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Maiato H, Lince-Faria M. The perpetual movements of anaphase. Cell Mol Life Sci 2010; 67:2251-69. [PMID: 20306325 PMCID: PMC11115923 DOI: 10.1007/s00018-010-0327-5] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2010] [Accepted: 02/17/2010] [Indexed: 12/29/2022]
Abstract
One of the most extraordinary events in the lifetime of a cell is the coordinated separation of sister chromatids during cell division. This is truly the essence of the entire mitotic process and the reason for the most profound morphological changes in cytoskeleton and nuclear organization that a cell may ever experience. It all occurs within a very short time window known as "anaphase", as if the cell had spent the rest of its existence getting ready for this moment in an ultimate act of survival. And there is a good reason for this: no space for mistakes. Problems in the distribution of chromosomes during cell division have been correlated with aneuploidy, a common feature observed in cancers and several birth defects, and the main cause of spontaneous abortion in humans. In this paper, we critically review the mechanisms of anaphase chromosome motion that resisted the scrutiny of more than 100 years of research, as part of a tribute to the pioneering work of Miguel Mota.
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Affiliation(s)
- Helder Maiato
- Instituto de Biologia Molecular e Celular, Universidade do Porto, Rua do Campo Alegre 823, 4150-180, Porto, Portugal.
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Barisic M, Sohm B, Mikolcevic P, Wandke C, Rauch V, Ringer T, Hess M, Bonn G, Geley S. Spindly/CCDC99 is required for efficient chromosome congression and mitotic checkpoint regulation. Mol Biol Cell 2010; 21:1968-81. [PMID: 20427577 PMCID: PMC2883941 DOI: 10.1091/mbc.e09-04-0356] [Citation(s) in RCA: 112] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
Human Spindly is required for kinetochore localization of cytoplasmic dynein, which is essential for poleward movement of chromosomes and for kinetochore protein streaming. In addition, Spindly controls the activity and kinetochore abundance of the RZZ complex, which contributes to microtubule attachment and mitotic checkpoint activity. Spindly recruits a fraction of cytoplasmic dynein to kinetochores for poleward movement of chromosomes and control of mitotic checkpoint signaling. Here we show that human Spindly is a cell cycle–regulated mitotic phosphoprotein that interacts with the Rod/ZW10/Zwilch (RZZ) complex. The kinetochore levels of Spindly are regulated by microtubule attachment and biorientation induced tension. Deletion mutants lacking the N-terminal half of the protein (NΔ253), or the conserved Spindly box (ΔSB), strongly localized to kinetochores and failed to respond to attachment or tension. In addition, these mutants prevented the removal of the RZZ complex and that of MAD2 from bioriented chromosomes and caused cells to arrest at metaphase, showing that RZZ-Spindly has to be removed from kinetochores to terminate mitotic checkpoint signaling. Depletion of Spindly by RNAi, however, caused cells to arrest in prometaphase because of a delay in microtubule attachment. Surprisingly, this defect was alleviated by codepletion of ZW10. Thus, Spindly is not only required for kinetochore localization of dynein but is a functional component of a mechanism that couples dynein-dependent poleward movement of chromosomes to their efficient attachment to microtubules.
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Affiliation(s)
- Marin Barisic
- Division of Molecular Pathophysiology, Biocenter, Innsbruck Medical University, 6020 Innsbruck, Austria
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Vogt E, Sanhaji M, Klein W, Seidel T, Wordeman L, Eichenlaub-Ritter U. MCAK is present at centromeres, midspindle and chiasmata and involved in silencing of the spindle assembly checkpoint in mammalian oocytes. Mol Hum Reprod 2010; 16:665-84. [PMID: 20406800 DOI: 10.1093/molehr/gaq025] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Mitotic centromere-associated kinesin (MCAK) is an ATP-dependent microtubule (MT) depolymerase regulated by Aurora kinase (AURK) phosphorylation and implicated in resolution of improper MT attachments in mitosis. Distribution of MCAK was studied in oocyte maturation by anti-MCAK antibody, anti-tubulin antibody, anti-AURKB antibody and anti-centromere antibody (ACA) and by the expression of MCAK-enhanced green fluorescent protein fusion protein in maturing mouse oocytes. Function was assessed by knockdown of MCAK and Mad2, by inhibiting AURK or the proteasome, by live imaging with polarization microscope and by chromosomal analysis. The results show that MCAK is transiently recruited to the nucleus and transits to spindle poles, ACA-positive domains and chiasmata at prometaphase I. At metaphase I and II, it is present at centrosomes and centromeres next to AURKB and checkpoint proteins Mad2 and BubR1. It is retained at centromeres at telophase I and also at the midbody. Knockdown of MCAK causes a delay in chromosome congression but does not prevent bipolar spindle assembly. MCAK knockdown also induces a meiosis I arrest, which is overcome by knockdown of Mad2 resulting in chiasma resolution, chromosome separation, formation of aberrant meiosis II spindles and increased hypoploidy. In conclusion, MCAK appears to possess a unique distribution and function in oocyte maturation. It is required for meiotic progression from meiosis I to meiosis II associated with silencing of the spindle assembly checkpoint. Alterations in abundance and activity of MCAK, as implicated in aged oocytes, may therefore contribute to the loss of control of cell cycle and chromosome behaviour, thus increasing risk for errors in chromosome segregation and aneuploidy.
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Affiliation(s)
- E Vogt
- Faculty of Biology, Gene Technology/Microbiology, University Bielefeld, Bielefeld, Germany
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37
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Bader JR, Vaughan KT. Dynein at the kinetochore: Timing, Interactions and Functions. Semin Cell Dev Biol 2010; 21:269-75. [PMID: 20045078 DOI: 10.1016/j.semcdb.2009.12.015] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2009] [Accepted: 12/22/2009] [Indexed: 01/31/2023]
Abstract
Kinetochores have been proposed to play multiple roles in mitotic chromosome alignment, including initial microtubule (MT) capture, monitoring MT attachments, prometaphase and anaphase chromosome movement and tension generation at metaphase. In addition, kinetochores are essential components of the spindle assembly checkpoint (SAC), and couple chromosome alignment with SAC silencing at metaphase. Although the molecular details of these activities remain under investigation, cytoplasmic dynein has been implicated in several aspects of MT and SAC regulation. Recent work clarifies the contribution of dynein to MT interactions and to events that drive anaphase onset. This review summarizes these studies and provides new models for dynein function.
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Affiliation(s)
- Jason R Bader
- Department of Biological Sciences, University of Notre Dame, Galvin Life Sciences Center, Notre Dame, IN 46556, United States
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38
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Abstract
Mitosis is the process by which a cell divides its genetic material equally into two daughter cells. Successful division requires that the two identical sister chromatids of a mitotic chromosome attach to the plus-ends of spindle microtubules (MTs) via their kinetochores, which are large protein structures built on centromeric DNA. Attachments between kinetochores and MTs must be persistent so that forces can be generated for chromosome movements, but at the same time they must be compliant, because attached MT plus-ends continuously polymerize and depolymerize to provide force for chromosome congression to the spindle equator. Both the attachment stability of kinetochore-MTs and the degree of dynamic instability exhibited by kinetochore-MTs must be precisely controlled to avoid errors in chromosome segregation. This chapter provides an overview of techniques used in cultured mammalian cells that measure stability and polymerization/depolymerization dynamics of kinetochore-MTs during mitosis.
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Affiliation(s)
- Jennifer G DeLuca
- Department of Biochemistry and Molecular Biology, Colorado State University, Fort Collins, Colorado 80523, USA
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Kobayashi T, Murayama T. Cell cycle-dependent microtubule-based dynamic transport of cytoplasmic dynein in mammalian cells. PLoS One 2009; 4:e7827. [PMID: 19915671 PMCID: PMC2772020 DOI: 10.1371/journal.pone.0007827] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2009] [Accepted: 10/15/2009] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND Cytoplasmic dynein complex is a large multi-subunit microtubule (MT)-associated molecular motor involved in various cellular functions including organelle positioning, vesicle transport and cell division. However, regulatory mechanism of the cell-cycle dependent distribution of dynein has not fully been understood. METHODOLOGY/PRINCIPAL FINDINGS Here we report live-cell imaging of cytoplasmic dynein in HeLa cells, by expressing multifunctional green fluorescent protein (mfGFP)-tagged 74-kDa intermediate chain (IC74). IC74-mfGFP was successfully incorporated into functional dynein complex. In interphase, dynein moved bi-directionally along with MTs, which might carry cargos such as transport vesicles. A substantial fraction of dynein moved toward cell periphery together with EB1, a member of MT plus end-tracking proteins (+TIPs), suggesting +TIPs-mediated transport of dynein. In late-interphase and prophase, dynein was localized at the centrosomes and the radial MT array. In prometaphase and metaphase, dynein was localized at spindle MTs where it frequently moved from spindle poles toward chromosomes or cell cortex. +TIPs may be involved in the transport of spindle dyneins. Possible kinetochore and cortical dyneins were also observed. CONCLUSIONS AND SIGNIFICANCE These findings suggest that cytoplasmic dynein is transported to the site of action in preparation for the following cellular events, primarily by the MT-based transport. The MT-based transport may have greater advantage than simple diffusion of soluble dynein in rapid and efficient transport of the limited concentration of the protein.
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Affiliation(s)
- Takuya Kobayashi
- Department of Pharmacology, Juntendo University School of Medicine, Tokyo, Japan
| | - Takashi Murayama
- Department of Pharmacology, Juntendo University School of Medicine, Tokyo, Japan
- * E-mail:
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40
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Abstract
Mitochondria in the cell bodies of neurons are transported down neuronal processes in response to changes in local energy and metabolic states. Because of their extreme polarity, neurons require specialized mechanisms to regulate mitochondrial transport and retention in axons. Our previous studies using syntaphilin (snph) knock-out mice provided evidence that SNPH targets to axonal mitochondria and controls their mobility through its static interaction with microtubules (MTs). However, the mechanisms regulating SNPH-mediated mitochondrial docking remain elusive. Here, we report an unexpected role for dynein light chain LC8. Using proteomic biochemical and cell biological assays combined with time-lapse imaging in live snph wild-type and mutant neurons, we reveal that LC8 regulates axonal mitochondrial mobility by binding to SNPH, thus enhancing the SNPH-MT docking interaction. Using mutagenesis assays, we mapped a seven-residue LC8-binding motif. Through this specific interaction, SNPH recruits LC8 to axonal mitochondria; such colocalization is abolished when neurons express SNPH mutants lacking the LC8-binding motif. Transient LC8 expression reduces mitochondrial mobility in snph (+/+) but not (-/-) neurons, suggesting that the observed effect of LC8 depends on the SNPH-mediated docking mechanism. In contrast, deleting the LC8-binding motif impairs the ability of SNPH to immobilize axonal mitochondria. Furthermore, circular dichroism spectrum analysis shows that LC8 stabilizes an alpha-helical coiled-coil within the MT-binding domain of SNPH against thermal unfolding. Thus, our study provides new mechanistic insights into controlling mitochondrial mobility through a dynamic interaction between the mitochondrial docking receptor and axonal cytoskeleton.
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Reis R, Feijão T, Gouveia S, Pereira AJ, Matos I, Sampaio P, Maiato H, Sunkel CE. Dynein and Mast/Orbit/CLASP have antagonistic roles in regulating kinetochore-microtubule plus-end dynamics. J Cell Sci 2009; 122:2543-53. [DOI: 10.1242/jcs.044818] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Establishment and maintenance of the mitotic spindle requires the balanced activity of microtubule-associated proteins and motors. In this study we have addressed how the microtubule plus-end tracking protein Mast/Orbit/CLASP and cytoplasmic dynein regulate this process in Drosophila melanogaster embryos and S2 cells. We show that Mast accumulates at kinetochores early in mitosis, which is followed by a poleward streaming upon microtubule attachment. This leads to a reduction of Mast levels at kinetochores during metaphase and anaphase that depends largely on the microtubule minus end-directed motor cytoplasmic dynein. Surprisingly, we also found that co-depletion of Dynein rescues spindle bipolarity in Mast-depleted cells, while restoring normal microtubule poleward flux. Our results suggest that Mast and Dynein have antagonistic roles in the local regulation of microtubule plus-end dynamics at kinetochores, which are important for the maintenance of spindle bipolarity and normal spindle length.
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Affiliation(s)
- Rita Reis
- IBMC Instituto de Biologia Molecular e Celular, Universidade do Porto, Rua do Campo Alegre 823, 4150-180 Porto, Portugal
| | - Tália Feijão
- IBMC Instituto de Biologia Molecular e Celular, Universidade do Porto, Rua do Campo Alegre 823, 4150-180 Porto, Portugal
| | - Susana Gouveia
- IBMC Instituto de Biologia Molecular e Celular, Universidade do Porto, Rua do Campo Alegre 823, 4150-180 Porto, Portugal
| | - António J. Pereira
- IBMC Instituto de Biologia Molecular e Celular, Universidade do Porto, Rua do Campo Alegre 823, 4150-180 Porto, Portugal
| | - Irina Matos
- IBMC Instituto de Biologia Molecular e Celular, Universidade do Porto, Rua do Campo Alegre 823, 4150-180 Porto, Portugal
| | - Paula Sampaio
- IBMC Instituto de Biologia Molecular e Celular, Universidade do Porto, Rua do Campo Alegre 823, 4150-180 Porto, Portugal
| | - Helder Maiato
- IBMC Instituto de Biologia Molecular e Celular, Universidade do Porto, Rua do Campo Alegre 823, 4150-180 Porto, Portugal
- Laboratory of Cell and Molecular Biology, Faculdade de Medicina, Universidade do Porto, 4200-319 Porto, Portugal
| | - Claudio E. Sunkel
- IBMC Instituto de Biologia Molecular e Celular, Universidade do Porto, Rua do Campo Alegre 823, 4150-180 Porto, Portugal
- ICBAS Instituto de Ciências Biomédicas Abel Salazar da Universidade do Porto, Largo do Prof. Abel Salazar, Porto, Portugal
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Tanaka K, Hirota T. Chromosome segregation machinery and cancer. Cancer Sci 2009; 100:1158-65. [PMID: 19432891 PMCID: PMC11158954 DOI: 10.1111/j.1349-7006.2009.01178.x] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2009] [Revised: 03/19/2009] [Accepted: 03/24/2009] [Indexed: 12/30/2022] Open
Abstract
Loss or gain of chromosomes is associated with many cancer cells. This property, called chromosome instability, might arise from a lesion in the chromosome segregation machinery. Essential for chromosome segregation are the proper connection of microtubules to kinetochores, and the synchronous segregation of sister chromatids in anaphase. Accuracy of these processes is ensured by two sophisticated machineries called the correction mechanism and the spindle assembly checkpoint. Here we outline the current understanding of the underlying mechanisms, and highlight recent challenging experiments to address how chromosome segregation failure might relate to tumorigenesis. Understanding these mechanisms may lead to the discovery of new and improved anticancer therapies.
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Affiliation(s)
- Kozo Tanaka
- Institute of Development, Aging and Cancer, Tohoku University, Sendai, Japan
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Raaijmakers JA, Tanenbaum ME, Maia AF, Medema RH. RAMA1 is a novel kinetochore protein involved in kinetochore-microtubule attachment. J Cell Sci 2009; 122:2436-45. [PMID: 19549680 DOI: 10.1242/jcs.051912] [Citation(s) in RCA: 88] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
During mitosis, kinetochores need to attach to microtubules emanating from spindle poles. Several protein complexes have been shown to mediate the kinetochore-microtubule interaction. However, with the continually growing number of newly identified kinetochore proteins, it is unclear whether all major components of the kinetochore-microtubule interface have been identified. We therefore performed a high-throughput RNAi screen to identify additional factors involved in kinetochore-microtubule attachment, and identified RAMA1 as a novel regulator of this process. Depletion of RAMA1 results in severe chromosome alignment defects and a checkpoint-dependent mitotic arrest. We show that this is due to reduced kinetochore-microtubule attachments. RAMA1 localizes to the spindle and to outer kinetochores throughout all phases of mitosis and is recruited to kinetochores by the core kinetochore-microtubule attachment factor Hec1. Interestingly, unlike Hec1, the association of RAMA1 with kinetochores is highly dynamic, suggesting that it is not a structural component of the kinetochore. Consistent with this, all other kinetochore proteins tested do not require RAMA1 for their kinetochore localization. Taken together, these results identify RAMA1 as a novel kinetochore protein and suggest that RAMA1 may have a direct role in mediating kinetochore-microtubule interactions.
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Affiliation(s)
- Jonne A Raaijmakers
- Department of Medical Oncology and Cancer Genomics Center, University Medical Center Utrecht, Utrecht, The Netherlands
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44
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Lu Y, Wang Z, Ge L, Chen N, Liu H. The RZZ complex and the spindle assembly checkpoint. Cell Struct Funct 2009; 34:31-45. [PMID: 19420794 DOI: 10.1247/csf.08040] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
The conserved protein Rod is found in various organisms. It is localized on the kinetochores or spindle microtubules during cell division. Rod is required for proper chromosome segregation during both mitosis and meiosis. The effects of rod mutations are similar for both equational and reductional divisions, giving rise to anaphases with lagging chromosomes and/or unequal numbers of chromosomes at the two poles. Recent studies have shown that Rod is a significant component of the mitotic checkpoint. It can form the RZZ complex with Zw10 and Zwilch, which plays an important role in maintaining a functional spindle assembly checkpoint.
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Affiliation(s)
- Yujian Lu
- MOE Key Laboratory of Arid and Grassland Ecology, Institute of Cell Biology, Life Science School, Lanzhou University, Lanzhou, PR China
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45
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Chan YW, Fava LL, Uldschmid A, Schmitz MHA, Gerlich DW, Nigg EA, Santamaria A. Mitotic control of kinetochore-associated dynein and spindle orientation by human Spindly. ACTA ACUST UNITED AC 2009; 185:859-74. [PMID: 19468067 PMCID: PMC2711594 DOI: 10.1083/jcb.200812167] [Citation(s) in RCA: 124] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Mitotic spindle formation and chromosome segregation depend critically on kinetochore-microtubule (KT-MT) interactions. A new protein, termed Spindly in Drosophila and SPDL-1 in C. elegans, was recently shown to regulate KT localization of dynein, but depletion phenotypes revealed striking differences, suggesting evolutionarily diverse roles of mitotic dynein. By characterizing the function of Spindly in human cells, we identify specific functions for KT dynein. We show that localization of human Spindly (hSpindly) to KTs is controlled by the Rod/Zw10/Zwilch (RZZ) complex and Aurora B. hSpindly depletion results in reduced inter-KT tension, unstable KT fibers, an extensive prometaphase delay, and severe chromosome misalignment. Moreover, depletion of hSpindly induces a striking spindle rotation, which can be rescued by co-depletion of dynein. However, in contrast to Drosophila, hSpindly depletion does not abolish the removal of MAD2 and ZW10 from KTs. Collectively, our data reveal hSpindly-mediated dynein functions and highlight a critical role of KT dynein in spindle orientation.
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Affiliation(s)
- Ying Wai Chan
- Department of Cell Biology, Max Planck Institute of Biochemistry, D-82152 Martinsried, Germany
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Anderson MA, Jodoin JN, Lee E, Hales KG, Hays TS, Lee LA. Asunder is a critical regulator of dynein-dynactin localization during Drosophila spermatogenesis. Mol Biol Cell 2009; 20:2709-21. [PMID: 19357193 DOI: 10.1091/mbc.e08-12-1165] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
Spermatogenesis uses mitotic and meiotic cell cycles coordinated with growth and differentiation programs to generate functional sperm. Our analysis of a Drosophila mutant has revealed that asunder (asun), which encodes a conserved protein, is an essential regulator of spermatogenesis. asun spermatocytes arrest during prophase of meiosis I. Strikingly, arrested spermatocytes contain free centrosomes that fail to stably associate with the nucleus. Spermatocytes that overcome arrest exhibit severe defects in meiotic spindle assembly, chromosome segregation, and cytokinesis. Furthermore, the centriole-derived basal body is detached from the nucleus in asun postmeiotic spermatids, resulting in abnormalities later in spermatogenesis. We find that asun spermatocytes and spermatids exhibit drastic reduction of perinuclear dynein-dynactin, a microtubule motor complex. We propose a model in which asun coordinates spermatogenesis by promoting dynein-dynactin recruitment to the nuclear surface, a poorly understood process required for nucleus-centrosome coupling at M phase entry and fidelity of meiotic divisions.
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Affiliation(s)
- Michael A Anderson
- Department of Cell and Developmental Biology, Vanderbilt University Medical Center, Nashville, TN 37232-8240, USA
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Whyte J, Bader JR, Tauhata SBF, Raycroft M, Hornick J, Pfister KK, Lane WS, Chan GK, Hinchcliffe EH, Vaughan PS, Vaughan KT. Phosphorylation regulates targeting of cytoplasmic dynein to kinetochores during mitosis. ACTA ACUST UNITED AC 2008; 183:819-34. [PMID: 19029334 PMCID: PMC2592828 DOI: 10.1083/jcb.200804114] [Citation(s) in RCA: 99] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Cytoplasmic dynein functions at several sites during mitosis; however, the basis of targeting to each site remains unclear. Tandem mass spectrometry analysis of mitotic dynein revealed a phosphorylation site in the dynein intermediate chains (ICs) that mediates binding to kinetochores. IC phosphorylation directs binding to zw10 rather than dynactin, and this interaction is needed for kinetochore dynein localization. Phosphodynein associates with kinetochores from nuclear envelope breakdown to metaphase, but bioriented microtubule (MT) attachment and chromosome alignment induce IC dephosphorylation. IC dephosphorylation stimulates binding to dynactin and poleward streaming. MT depolymerization, release of kinetochore tension, and a PP1-γ mutant each inhibited IC dephosphorylation, leading to the retention of phosphodynein at kinetochores and reduced poleward streaming. The depletion of kinetochore dynactin by moderate levels of p50(dynamitin) expression disrupted the ability of dynein to remove checkpoint proteins by streaming at metaphase but not other aspects of kinetochore dynein activity. Together, these results suggest a new model for localization of kinetochore dynein and the contribution of kinetochore dynactin.
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Affiliation(s)
- Jacqueline Whyte
- Department of Biological Sciences and 2Notre Dame Integrated Imaging Facility, University of Notre Dame, Notre Dame, IN 46556, USA
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48
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Abstract
The attachment of chromosomes to spindle microtubules during mitosis is a delicate and intricate process on which eukaryotic cells critically depend to maintain their ploidy. In this issue of Genes & Development, Gassmann and colleagues (pp. 2385-2399 present an analysis of the recently discovered Spindly/SPDL-1 protein that casts new lights onto the attachment process and the way it relates to the control of cell cycle progression.
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Affiliation(s)
- Filiz Civril
- Department of Experimental Oncology, European Institute of Oncology, I-20139 Milan, Italy
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49
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Varma D, Monzo P, Stehman SA, Vallee RB. Direct role of dynein motor in stable kinetochore-microtubule attachment, orientation, and alignment. ACTA ACUST UNITED AC 2008; 182:1045-54. [PMID: 18809721 PMCID: PMC2542467 DOI: 10.1083/jcb.200710106] [Citation(s) in RCA: 87] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Cytoplasmic dynein has been implicated in diverse mitotic functions, several involving its association with kinetochores. Much of the supporting evidence comes from inhibition of dynein regulatory factors. To obtain direct insight into kinetochore dynein function, we expressed a series of dynein tail fragments, which we find displace motor-containing dynein heavy chain (HC) from kinetochores without affecting other subunits, regulatory factors, or microtubule binding proteins. Cells with bipolar mitotic spindles progress to late prometaphase-metaphase at normal rates. However, the dynein tail, dynactin, Mad1, and BubR1 persist at the aligned kinetochores, which is consistent with a role for dynein in self-removal and spindle assembly checkpoint inactivation. Kinetochore pairs also show evidence of misorientation relative to the spindle equator and abnormal oscillatory behavior. Further, kinetochore microtubule bundles are severely destabilized at reduced temperatures. Dynein HC RNAi and injection of anti-dynein antibody in MG132-arrested metaphase cells produced similar effects. These results identify a novel function for the dynein motor in stable microtubule attachment and maintenance of kinetochore orientation during metaphase chromosome alignment.
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Affiliation(s)
- Dileep Varma
- Department of Pathology and Cell Biology, Columbia University, New York, NY 10032, USA
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50
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Mische S, He Y, Ma L, Li M, Serr M, Hays TS. Dynein light intermediate chain: an essential subunit that contributes to spindle checkpoint inactivation. Mol Biol Cell 2008; 19:4918-29. [PMID: 18799620 DOI: 10.1091/mbc.e08-05-0483] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
The dynein light intermediate chain (LIC) is a subunit unique to the cytoplasmic form of dynein, but how it contributes to dynein function is not fully understood. Previous work has established that the LIC homodimer binds directly to the dynein heavy chain and may mediate the attachment of dynein to centrosomes and other cargoes. Here, we report our characterization of the LIC in Drosophila. Unlike vertebrates, in which two Lic genes encode multiple subunit isoforms, the Drosophila LIC is encoded by a single gene. We determined that the single LIC polypeptide is phosphorylated, and that different phosphoisoforms can assemble into the dynein motor complex. Our mutational analyses demonstrate that, similar to other dynein subunits, the Drosophila LIC is required for zygotic development, germline specification of the oocyte, and mitotic cell division. We show that RNA interference depletion of LIC in Drosophila S2 cells does not block the recruitment of a dynein complex to kinetochores, but it does delay inactivation of Mad2 signaling and mitotic progression. Our observations suggest the LIC contributes to a broad range of dynein functions.
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Affiliation(s)
- Sarah Mische
- Department of Genetics, Cell Biology, and Development, University of Minnesota, Minneapolis, MN 55455, USA
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