1
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Lima JT, Pereira AJ, Ferreira JG. The LINC complex ensures accurate centrosome positioning during prophase. Life Sci Alliance 2024; 7:e202302404. [PMID: 38228373 DOI: 10.26508/lsa.202302404] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2023] [Revised: 01/03/2024] [Accepted: 01/04/2024] [Indexed: 01/18/2024] Open
Abstract
Accurate centrosome separation and positioning during early mitosis relies on force-generating mechanisms regulated by a combination of extracellular, cytoplasmic, and nuclear cues. The identity of the nuclear cues involved in this process remains largely unknown. Here, we investigate how the prophase nucleus contributes to centrosome positioning during the initial stages of mitosis, using a combination of cell micropatterning, high-resolution live-cell imaging, and quantitative 3D cellular reconstruction. We show that in untransformed RPE-1 cells, centrosome positioning is regulated by a nuclear signal, independently of external cues. This nuclear mechanism relies on the linker of nucleoskeleton and cytoskeleton complex that controls the timely loading of dynein on the nuclear envelope (NE), providing spatial cues for robust centrosome positioning on the shortest nuclear axis, before nuclear envelope permeabilization. Our results demonstrate how nuclear-cytoskeletal coupling maintains a robust centrosome positioning mechanism to ensure efficient mitotic spindle assembly.
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Affiliation(s)
- Joana T Lima
- https://ror.org/04wjk1035 Instituto de Investigação e Inovação em Saúde (i3S), Porto, Portugal
- Departamento de Biomedicina, Faculdade de Medicina do Porto, Unidade de Biologia Experimental, Porto, Portugal
- https://ror.org/04wjk1035 Programa Doutoral em Biomedicina, Faculdade de Medicina, Universidade do Porto, Porto, Portugal
| | - António J Pereira
- https://ror.org/04wjk1035 Instituto de Investigação e Inovação em Saúde (i3S), Porto, Portugal
| | - Jorge G Ferreira
- https://ror.org/04wjk1035 Instituto de Investigação e Inovação em Saúde (i3S), Porto, Portugal
- Departamento de Biomedicina, Faculdade de Medicina do Porto, Unidade de Biologia Experimental, Porto, Portugal
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2
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Leguay K, Decelle B, Elkholi IE, Bouvier M, Côté JF, Carréno S. Interphase microtubule disassembly is a signaling cue that drives cell rounding at mitotic entry. J Cell Biol 2022; 221:213183. [PMID: 35482006 DOI: 10.1083/jcb.202109065] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2021] [Revised: 02/03/2022] [Accepted: 04/05/2022] [Indexed: 11/22/2022] Open
Abstract
At mitotic entry, reorganization of the actomyosin cortex prompts cells to round-up. Proteins of the ezrin, radixin, and moesin family (ERM) play essential roles in this process by linking actomyosin forces to the plasma membrane. Yet, the cell-cycle signal that activates ERMs at mitotic entry is unknown. By screening a compound library using newly developed biosensors, we discovered that drugs that disassemble microtubules promote ERM activation. We further demonstrated that disassembly of interphase microtubules at mitotic entry directs ERM activation and metaphase cell rounding through GEF-H1, a Rho-GEF inhibited by microtubule binding, RhoA, and its kinase effector SLK. We finally demonstrated that GEF-H1 and Ect2, another Rho-GEF previously identified to control actomyosin forces, act together to drive activation of ERMs and cell rounding in metaphase. In summary, we report microtubule disassembly as a cell-cycle signal that controls a signaling network ensuring that actomyosin forces are efficiently integrated at the plasma membrane to promote cell rounding at mitotic entry.
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Affiliation(s)
- Kévin Leguay
- Institute for Research in Immunology and Cancer, Université de Montréal, Montréal, Quebec, Canada.,Cellular Mechanisms of Morphogenesis during Mitosis and Cell Motility lab, Université de Montréal, Montréal, Quebec, Canada
| | - Barbara Decelle
- Institute for Research in Immunology and Cancer, Université de Montréal, Montréal, Quebec, Canada.,Cellular Mechanisms of Morphogenesis during Mitosis and Cell Motility lab, Université de Montréal, Montréal, Quebec, Canada
| | - Islam E Elkholi
- Montréal Clinical Research Institute, Montréal, Quebec, Canada.,Cytoskeletal Organization and Cell Migration lab, Université de Montréal, Montréal, Quebec, Canada
| | - Michel Bouvier
- Institute for Research in Immunology and Cancer, Université de Montréal, Montréal, Quebec, Canada.,institution>Molecular Pharmacology Lab, Université de Montréal, Montréal, Quebec, Canada.,Department of Biochemistry and Molecular Medicine, Université de Montréal, Montréal, Quebec, Canada
| | - Jean-François Côté
- Montréal Clinical Research Institute, Montréal, Quebec, Canada.,Department of Biochemistry and Molecular Medicine, Université de Montréal, Montréal, Quebec, Canada.,Department of Medicine, McGill University, Montréal, Quebec, Canada.,Department of Anatomy and Cell Biology, McGill University, Montréal, Quebec, Canada.,Cytoskeletal Organization and Cell Migration lab, Université de Montréal, Montréal, Quebec, Canada
| | - Sébastien Carréno
- Institute for Research in Immunology and Cancer, Université de Montréal, Montréal, Quebec, Canada.,Cellular Mechanisms of Morphogenesis during Mitosis and Cell Motility lab, Université de Montréal, Montréal, Quebec, Canada.,Department of Pathology and Cell Biology, Université de Montréal, Montréal, Quebec, Canada
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3
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Asthana J, Cade NI, Normanno D, Lim WM, Surrey T. Gradual compaction of the central spindle decreases its dynamicity in PRC1 and EB1 gene-edited cells. Life Sci Alliance 2021; 4:4/12/e202101222. [PMID: 34580180 PMCID: PMC8500333 DOI: 10.26508/lsa.202101222] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2021] [Revised: 09/13/2021] [Accepted: 09/15/2021] [Indexed: 11/24/2022] Open
Abstract
Although different anaphase proteins bind with characteristically different strength to the central spindle, the overall central spindle dynamicity slows down as mitosis proceeds. During mitosis, the spindle undergoes morphological and dynamic changes. It reorganizes at the onset of the anaphase when the antiparallel bundler PRC1 accumulates and recruits central spindle proteins to the midzone. Little is known about how the dynamic properties of the central spindle change during its morphological changes in human cells. Using gene editing, we generated human cells that express from their endogenous locus fluorescent PRC1 and EB1 to quantify their native spindle distribution and binding/unbinding turnover. EB1 plus end tracking revealed a general slowdown of microtubule growth, whereas PRC1, similar to its yeast orthologue Ase1, binds increasingly strongly to compacting antiparallel microtubule overlaps. KIF4A and CLASP1 bind more dynamically to the central spindle, but also show slowing down turnover. These results show that the central spindle gradually becomes more stable during mitosis, in agreement with a recent “bundling, sliding, and compaction” model of antiparallel midzone bundle formation in the central spindle during late mitosis.
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Affiliation(s)
- Jayant Asthana
- The Francis Crick Institute, London, UK.,Centre for Genomic Regulation (CRG), Barcelona Institute of Science and Technology (BIST), Barcelona, Spain
| | | | - Davide Normanno
- Centre for Genomic Regulation (CRG), Barcelona Institute of Science and Technology (BIST), Barcelona, Spain
| | - Wei Ming Lim
- The Francis Crick Institute, London, UK.,Centre for Genomic Regulation (CRG), Barcelona Institute of Science and Technology (BIST), Barcelona, Spain
| | - Thomas Surrey
- The Francis Crick Institute, London, UK .,Centre for Genomic Regulation (CRG), Barcelona Institute of Science and Technology (BIST), Barcelona, Spain.,Catalan Institution for Research and Advanced Studies (ICREA), Barcelona, Spain
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4
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Lynn NA, Martinez E, Nguyen H, Torres JZ. The Mammalian Family of Katanin Microtubule-Severing Enzymes. Front Cell Dev Biol 2021; 9:692040. [PMID: 34414183 PMCID: PMC8369831 DOI: 10.3389/fcell.2021.692040] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2021] [Accepted: 06/04/2021] [Indexed: 12/12/2022] Open
Abstract
The katanin family of microtubule-severing enzymes is critical for cytoskeletal rearrangements that affect key cellular processes like division, migration, signaling, and homeostasis. In humans, aberrant expression, or dysfunction of the katanins, is linked to developmental, proliferative, and neurodegenerative disorders. Here, we review current knowledge on the mammalian family of katanins, including an overview of evolutionary conservation, functional domain organization, and the mechanisms that regulate katanin activity. We assess the function of katanins in dividing and non-dividing cells and how their dysregulation promotes impaired ciliary signaling and defects in developmental programs (corticogenesis, gametogenesis, and neurodevelopment) and contributes to neurodegeneration and cancer. We conclude with perspectives on future katanin research that will advance our understanding of this exciting and dynamic class of disease-associated enzymes.
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Affiliation(s)
- Nicole A. Lynn
- Department of Chemistry and Biochemistry, University of California, Los Angeles, Los Angeles, CA, United States
| | - Emily Martinez
- Department of Chemistry and Biochemistry, University of California, Los Angeles, Los Angeles, CA, United States
| | - Hieu Nguyen
- Department of Chemistry and Biochemistry, University of California, Los Angeles, Los Angeles, CA, United States
| | - Jorge Z. Torres
- Department of Chemistry and Biochemistry, University of California, Los Angeles, Los Angeles, CA, United States
- Molecular Biology Institute, University of California, Los Angeles, Los Angeles, CA, United States
- Jonsson Comprehensive Cancer Center, University of California, Los Angeles, Los Angeles, CA, United States
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5
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Dantas M, Lima JT, Ferreira JG. Nucleus-Cytoskeleton Crosstalk During Mitotic Entry. Front Cell Dev Biol 2021; 9:649899. [PMID: 33816500 PMCID: PMC8014196 DOI: 10.3389/fcell.2021.649899] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2021] [Accepted: 02/26/2021] [Indexed: 12/30/2022] Open
Abstract
In preparation for mitosis, cells undergo extensive reorganization of the cytoskeleton and nucleus, so that chromosomes can be efficiently segregated into two daughter cells. Coordination of these cytoskeletal and nuclear events occurs through biochemical regulatory pathways, orchestrated by Cyclin-CDK activity. However, recent studies provide evidence that physical forces are also involved in the early steps of spindle assembly. Here, we will review how the crosstalk of physical forces and biochemical signals coordinates nuclear and cytoplasmic events during the G2-M transition, to ensure efficient spindle assembly and faithful chromosome segregation.
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Affiliation(s)
- Margarida Dantas
- Instituto de Investigação e Inovação em Saúde - i3S, University of Porto, Porto, Portugal.,BiotechHealth Ph.D. Programme, University of Porto, Porto, Portugal.,Instituto de Ciências Biomédicas Abel Salazar (ICBAS), University of Porto, Porto, Portugal
| | - Joana T Lima
- Instituto de Investigação e Inovação em Saúde - i3S, University of Porto, Porto, Portugal.,Departamento de Biomedicina, Faculdade de Medicina, University of Porto, Porto, Portugal
| | - Jorge G Ferreira
- Instituto de Investigação e Inovação em Saúde - i3S, University of Porto, Porto, Portugal.,Departamento de Biomedicina, Faculdade de Medicina, University of Porto, Porto, Portugal
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6
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Nunes V, Ferreira JG. From the cytoskeleton to the nucleus: An integrated view on early spindle assembly. Semin Cell Dev Biol 2021; 117:42-51. [PMID: 33726956 DOI: 10.1016/j.semcdb.2021.03.006] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2021] [Revised: 03/09/2021] [Accepted: 03/10/2021] [Indexed: 12/01/2022]
Abstract
Accurate chromosome segregation requires a complete restructuring of cellular organization. Microtubules remodel to assemble a mitotic spindle and the actin cytoskeleton rearranges to form a stiff actomyosin cortex. These cytoplasmic events must be spatially and temporally coordinated with mitotic chromosome condensation and nuclear envelope permeabilization, in order to ensure mitotic timing and fidelity. Here, we discuss the main cytoskeletal and nuclear events that occur during mitotic entry in proliferating animal cells, focusing on their coordinated contribution for early mitotic spindle assembly. We will also explore recent progress in understanding their regulatory biochemical and mechanical pathways.
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Affiliation(s)
- Vanessa Nunes
- Instituto de Investigação e Inovação em Saúde - i3S, University of Porto, Porto, Portugal; BiotechHealth PhD Programe, Instituto de Ciências Biomédicas Abel Salazar (ICBAS), University of Porto, Porto, Portugal
| | - Jorge G Ferreira
- Instituto de Investigação e Inovação em Saúde - i3S, University of Porto, Porto, Portugal; Departamento de Biomedicina, Faculdade de Medicina, University of Porto, Porto, Portugal.
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7
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Singh D, Schmidt N, Müller F, Bange T, Bird AW. Destabilization of Long Astral Microtubules via Cdk1-Dependent Removal of GTSE1 from Their Plus Ends Facilitates Prometaphase Spindle Orientation. Curr Biol 2020; 31:766-781.e8. [PMID: 33333009 DOI: 10.1016/j.cub.2020.11.040] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2020] [Revised: 09/25/2020] [Accepted: 11/16/2020] [Indexed: 12/19/2022]
Abstract
The precise regulation of microtubule dynamics over time and space in dividing cells is critical for several mitotic mechanisms that ultimately enable cell proliferation, tissue organization, and development. Astral microtubules, which extend from the centrosome toward the cell cortex, must be present for the mitotic spindle to properly orient, as well as for the faithful execution of anaphase and cytokinesis. However, little is understood about how the dynamic properties of astral microtubules are regulated spatiotemporally, or the contribution of astral microtubule dynamics to spindle positioning. The mitotic regulator Cdk1-CyclinB promotes destabilization of centrosomal microtubules and increased microtubule dynamics as cells enter mitosis, but how Cdk1 activity modulates astral microtubule stability, and whether it impacts spindle positioning, is unknown. Here, we uncover a mechanism revealing that Cdk1 destabilizes astral microtubules in prometaphase and thereby influences spindle reorientation. Phosphorylation of the EB1-dependent microtubule plus-end tracking protein GTSE1 by Cdk1 in early mitosis abolishes its interaction with EB1 and recruitment to microtubule plus ends. Loss of Cdk1 activity, or mutation of phosphorylation sites in GTSE1, induces recruitment of GTSE1 to growing microtubule plus ends in mitosis. This decreases the catastrophe frequency of astral microtubules and causes an increase in the number of long astral microtubules reaching the cell cortex, which restrains the ability of cells to reorient spindles along the long cellular axis in early mitosis. Astral microtubules thus must not only be present but also dynamic to allow the spindle to reorient, a state assisted by selective destabilization of long astral microtubules via Cdk1.
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Affiliation(s)
- Divya Singh
- Max Planck Institute of Molecular Physiology, Otto-Hahn-Strasse 11, 44227 Dortmund, Germany
| | - Nadine Schmidt
- Max Planck Institute of Molecular Physiology, Otto-Hahn-Strasse 11, 44227 Dortmund, Germany
| | - Franziska Müller
- Max Planck Institute of Molecular Physiology, Otto-Hahn-Strasse 11, 44227 Dortmund, Germany
| | - Tanja Bange
- Department for Systems Chronobiology, Institute of Medical Psychology, LMU Munich, Goethestrasse 31/ I, 80336 Munich, Germany
| | - Alexander W Bird
- Max Planck Institute of Molecular Physiology, Otto-Hahn-Strasse 11, 44227 Dortmund, Germany.
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8
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Nuclear Isoforms of Neurofibromin Are Required for Proper Spindle Organization and Chromosome Segregation. Cells 2020; 9:cells9112348. [PMID: 33114250 PMCID: PMC7690890 DOI: 10.3390/cells9112348] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2020] [Revised: 10/20/2020] [Accepted: 10/22/2020] [Indexed: 12/30/2022] Open
Abstract
Mitotic spindles are highly organized, microtubule (MT)-based, transient structures that serve the fundamental function of unerring chromosome segregation during cell division and thus of genomic stability during tissue morphogenesis and homeostasis. Hence, a multitude of MT-associated proteins (MAPs) regulates the dynamic assembly of MTs in preparation for mitosis. Some tumor suppressors, normally functioning to prevent tumor development, have now emerged as significant MAPs. Among those, neurofibromin, the product of the Neurofibromatosis-1 gene (NF1), a major Ras GTPase activating protein (RasGAP) in neural cells, controls also the critical function of chromosome congression in astrocytic cellular contexts. Cell type- and development-regulated splicings may lead to the inclusion or exclusion of NF1exon51, which bears a nuclear localization sequence (NLS) for nuclear import at G2; yet the functions of the produced NLS and ΔNLS neurofibromin isoforms have not been previously addressed. By using a lentiviral shRNA system, we have generated glioblastoma SF268 cell lines with conditional knockdown of NLS or ΔNLS transcripts. In dissecting the roles of NLS or ΔNLS neurofibromins, we found that NLS-neurofibromin knockdown led to increased density of cytosolic MTs but loss of MT intersections, anastral spindles featuring large hollows and abnormal chromosome positioning, and finally abnormal chromosome segregation and increased micronuclei frequency. Therefore, we propose that NLS neurofibromin isoforms exert prominent mitotic functions.
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9
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Xu AM, He CJ, Tuerxun Z, Anikezi A. FAM172A affects cell proliferation and apoptosis not by targeting β-tubulin in HepG2 cells. Transl Cancer Res 2020; 9:5637-5644. [PMID: 35117927 PMCID: PMC8797783 DOI: 10.21037/tcr-20-2868] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2020] [Accepted: 09/15/2020] [Indexed: 11/17/2022]
Abstract
BACKGROUND Microtubules pull chromosomes apart during cell mitosis and take part in cell division, Inhibiting the formation of spindle microtubules during mitosis has become one of the current anti-tumor research strategies. Earlier studies have found that the family with sequence similarity 172, member A (FAM172A) can significantly inhibit the proliferation of human colorectal cancer cell line LOVO cells and promote apoptosis. The purpose of this study was to investigate the biological effects of FAM172A on liver cancer cells and the interaction mechanism with tubulin. METHODS Use STRING software predicted the interactions between FAM172A and β-tubulin, and verify by immunoprecipitation. Real-Time qPCR was used to determine the expression levels of β-tubulin in liver cancer cell line HepG2, western blot was performed to detect protein expression levels. Immunofluorescence experiment to detect the distribution, shape and the dynamic behavior of depolymerization-aggregation of β-tubulin in cells. MTT, wound healing and Transwell assay were employed to determine cell proliferation, migration and invasion respectively. Flow cytometry was conducted to determine cell cycle and apoptosis. RESULTS There is no interactions between FAM172A and β-tubulin. We determined that when FAM172A was up-regulated or down-regulated, the mRNA and protein levels of β-tubulin did not change significantly (P>0.05). Furthermore, the distribution, shape of β-tubulin in cells, and the dynamic behavior of depolymerization-aggregation was not affected. After FAM172A overexpression, the migration and invasion of HepG2 cells were significantly inhibited (P<0.05), the cell proliferation was also significantly inhibited (P<0.05) and was time-dependent. The HepG2 cells had apparent S phase arrest and apoptosis (P<0.05). After interfering with FAM172A, the opposite result will appear. CONCLUSIONS The results show that FAM172A may be a new tumor suppressor gene, which has a specific role in cell cycle control and cell proliferation, but the specific mechanism of action has not been explained in this study and needs further exploration.
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Affiliation(s)
- Ai-Min Xu
- Department of Laboratory, The First People's Hospital of Kashgar, Kashi, Kashi 844000, China
| | - Chuan-Jiang He
- Department of Laboratory, The First People's Hospital of Kashgar, Kashi, Kashi 844000, China
| | - Zureguli Tuerxun
- Department of Laboratory, The First People's Hospital of Kashgar, Kashi, Kashi 844000, China
| | - Abuduaini Anikezi
- Department of Laboratory, The First People's Hospital of Kashgar, Kashi, Kashi 844000, China
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10
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Chen H, Li Y, Li Y, Chen Z, Xie L, Li W, Zhu Y, Xue H, Koeffler HP, Wu W, Hu K, Yin D. PARK2 promotes mitochondrial pathway of apoptosis and antimicrotubule drugs chemosensitivity via degradation of phospho-BCL-2. Am J Cancer Res 2020; 10:9984-10000. [PMID: 32929329 PMCID: PMC7481404 DOI: 10.7150/thno.47044] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2020] [Accepted: 07/27/2020] [Indexed: 02/06/2023] Open
Abstract
Rationale: Neoadjuvant chemotherapy has become the standard treatment of locally advanced breast cancer. Antimicrotubule drugs and DNA-damaging drugs are the most popular medicines used for neoadjuvant chemotherapy. However, we are unable to predict which chemotherapeutic drug will benefit to an individual patient. PARK2 as a tumor suppressor in breast cancer has been reported. While the role of PARK2 in chemotherapy response remains unknown. In this study, we explore the impact of PARK2 on chemosensitivity in breast cancer. Methods: PARK2 expression in breast cancer patients with different neoadjuvant chemotherapeutic regimens was studied using immunohistochemistry. Data was correlated to disease-free survival (DFS), overall survival and pathologic complete response (pCR). The functional roles of PARK2 were demonstrated by a series of in vitro and in vivo experiments. Including mass spectrometry, Co-immunoprecipitation, isolation of subcellular fractionation, fluorescence microscopy, in vivo ubiquitination assay and luciferase analyses. Results: Highly expressed PARK2 predicted better response to antimicrotubule drugs-containing regimen associated with higher rate of pathologic complete response (pCR). In contrast, PARK2 expression did not predict response to the DNA-damaging drugs regimen. Following antimicrotubule drugs treatment, levels of PARK2 was upregulated due to the repression of STAT3-mediated transcriptional inhibition of PARK2. Moreover, overexpression of PARK2 specifically rendered cells more sensitive to antimicrotubule drugs, but not to DNA-damaging drugs. Depletion of PARK2 enhanced resistance to antimicrotubule drugs. Mechanistically, PARK2 markedly activated the mitochondrial pathway of apoptosis after exposure to antimicrotubule drugs. This occurred through downregulating the antiapoptotic protein, phospho-BCL-2. BCL-2 phosphorylation can be specifically induced by antimicrotubule drugs, whereas DNA-damaging drugs do not. Notably, PARK2 interacted with phospho-BCL-2 (Ser70) and promoted ubiquitination of BCL-2 in an E3 ligase-dependent manner. Hence, PARK2 significantly enhanced the chemosensitivity of antimicrotubule drugs both in vitro and in vivo, while loss-of-function PARK2 mutants did not. Conclusions: Our findings explained why PARK2 selectively confers chemosensitivity to antimicrotubule drugs, but not to DNA-damaging drugs. In addition, we identified PARK2 as a novel mediator of antimicrotubule drugs sensitivity, which can predict response of breast cancer patients to antimicrotubule drugs-containing regime.
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11
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Guilloux G, Gibeaux R. Mechanisms of spindle assembly and size control. Biol Cell 2020; 112:369-382. [PMID: 32762076 DOI: 10.1111/boc.202000065] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2020] [Revised: 08/03/2020] [Accepted: 08/03/2020] [Indexed: 01/09/2023]
Abstract
The spindle is crucial for cell division by allowing the faithful segregation of replicated chromosomes to daughter cells. Proper segregation is ensured only if microtubules (MTs) and hundreds of other associated factors interact to assemble this complex structure with the appropriate architecture and size. In this review, we describe the latest view of spindle organisation as well as the molecular gradients and mechanisms underlying MT nucleation and spindle assembly. We then discuss the overlapping physical and molecular constraints that dictate spindle morphology, concluding with a focus on spindle size regulation.
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Affiliation(s)
- Gabriel Guilloux
- Univ Rennes, CNRS, IGDR [(Institute of Genetics and Development of Rennes)] - UMR 6290, F-35000 Rennes, France
| | - Romain Gibeaux
- Univ Rennes, CNRS, IGDR [(Institute of Genetics and Development of Rennes)] - UMR 6290, F-35000 Rennes, France
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12
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Kamal MA, Al-Zahrani MH, Khan SH, Khan MH, Al-Subhi HA, Kuerban A, Aslam M, Al-Abbasi FA, Anwar F. Tubulin Proteins in Cancer Resistance: A Review. Curr Drug Metab 2020; 21:178-185. [DOI: 10.2174/1389200221666200226123638] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2019] [Revised: 11/26/2019] [Accepted: 12/03/2019] [Indexed: 12/26/2022]
Abstract
Cancer cells are altered with cell cycle genes or they are mutated, leading to a high rate of proliferation
compared to normal cells. Alteration in these genes leads to mitosis dysregulation and becomes the basis of tumor
progression and resistance to many drugs. The drugs which act on the cell cycle fail to arrest the process, making
cancer cell non-responsive to apoptosis or cell death. Vinca alkaloids and taxanes fall in this category and are
referred to as antimitotic agents. Microtubule proteins play an important role in mitosis during cell division as a
target site for vinca alkaloids and taxanes. These proteins are dynamic in nature and are composed of α-β-tubulin
heterodimers. β-tubulin specially βΙΙΙ isotype is generally altered in expression within cancerous cells. Initially,
these drugs were very effective in the treatment of cancer but failed to show their desired action after initial
chemotherapy. The present review highlights some of the important targets and their mechanism of resistance
offered by cancer cells with new promising drugs from natural sources that can lead to the development of a new
approach to chemotherapy.
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Affiliation(s)
- Mohammad Amjad Kamal
- Metabolomics and Enzymology Unit, Fundamental and Applied Biology Group, King Fahd Medical Research Center, King Abdulaziz University, Jeddah 21589, Saudi Arabia
| | - Maryam Hassan Al-Zahrani
- Department of Biochemistry, Faculty of Science, King Abdulaziz University, Jeddah 21589, Saudi Arabia
| | - Salman Hasan Khan
- Department of Orthodontics, and Dentofacial Orthopaedics, TMU Dental College, Moradabad, Uttar Pradesh, India
| | - Mateen Hasan Khan
- Department of Pharmacology, Shri Venkateshwara University, Gajraula, Amroha, Uttar Pradesh, India
| | - Hani Awad Al-Subhi
- Department of Biochemistry, Faculty of Science, King Abdulaziz University, Jeddah 21589, Saudi Arabia
| | - Abudukadeer Kuerban
- Department of Biochemistry, Faculty of Science, King Abdulaziz University, Jeddah 21589, Saudi Arabia
| | - Muhammad Aslam
- Department of Statistics, Faculy of Science, King Abdulaziz University, Jeddah 21589, Saudi Arabia
| | - Fahad Ahmed Al-Abbasi
- Department of Biochemistry, Faculty of Science, King Abdulaziz University, Jeddah 21589, Saudi Arabia
| | - Firoz Anwar
- Department of Biochemistry, Faculty of Science, King Abdulaziz University, Jeddah 21589, Saudi Arabia
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13
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Nunes V, Dantas M, Castro D, Vitiello E, Wang I, Carpi N, Balland M, Piel M, Aguiar P, Maiato H, Ferreira JG. Centrosome-nuclear axis repositioning drives the assembly of a bipolar spindle scaffold to ensure mitotic fidelity. Mol Biol Cell 2020; 31:1675-1690. [PMID: 32348198 PMCID: PMC7521851 DOI: 10.1091/mbc.e20-01-0047] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
During the initial stages of cell division, the cytoskeleton is extensively reorganized so that a bipolar mitotic spindle can be correctly assembled. This process occurs through the action of molecular motors, cytoskeletal networks, and the nucleus. How the combined activity of these different components is spatiotemporally regulated to ensure efficient spindle assembly remains unclear. To investigate how cell shape, cytoskeletal organization, and molecular motors cross-talk to regulate initial spindle assembly, we use a combination of micropatterning with high-resolution imaging and 3D cellular reconstruction. We show that during prophase, centrosomes and nucleus reorient so that centrosomes are positioned on the shortest nuclear axis at nuclear envelope (NE) breakdown. We also find that this orientation depends on a combination of centrosome movement controlled by Arp2/3-mediated regulation of microtubule dynamics and Dynein-generated forces on the NE that regulate nuclear reorientation. Finally, we observe this centrosome configuration favors the establishment of an initial bipolar spindle scaffold, facilitating chromosome capture and accurate segregation, without compromising division plane orientation.
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Affiliation(s)
- Vanessa Nunes
- Instituto de Investigação e Inovação em Saúde (i3S), 4200-135 Porto, Portugal.,Instituto de Biologia Celular e Molecular (IBMC), 4200-135 Porto, Portugal.,BiotechHealth PhD program, Instituto de Ciências Biomédicas (ICBAS), 4050-313 Porto, Portugal
| | - Margarida Dantas
- Instituto de Investigação e Inovação em Saúde (i3S), 4200-135 Porto, Portugal.,Instituto de Biologia Celular e Molecular (IBMC), 4200-135 Porto, Portugal.,BiotechHealth PhD program, Instituto de Ciências Biomédicas (ICBAS), 4050-313 Porto, Portugal
| | - Domingos Castro
- Instituto de Investigação e Inovação em Saúde (i3S), 4200-135 Porto, Portugal.,Instituto Nacional de Engenharia Biomédica (INEB), 4200-135 Porto, Portugal
| | - Elisa Vitiello
- Laboratoire Interdisciplinaire de Physique, Université Joseph Fourier (Grenoble 1) 38058, France
| | - Irène Wang
- Laboratoire Interdisciplinaire de Physique, Université Joseph Fourier (Grenoble 1) 38058, France
| | - Nicolas Carpi
- Institut Curie, PSL Research University, CNRS, UMR 144, F-75005 Paris, France.,Institut Pierre-Gilles de Gennes, PSL Research University, F-75005 Paris, France
| | - Martial Balland
- Laboratoire Interdisciplinaire de Physique, Université Joseph Fourier (Grenoble 1) 38058, France
| | - Matthieu Piel
- Institut Curie, PSL Research University, CNRS, UMR 144, F-75005 Paris, France.,Institut Pierre-Gilles de Gennes, PSL Research University, F-75005 Paris, France
| | - Paulo Aguiar
- Instituto de Investigação e Inovação em Saúde (i3S), 4200-135 Porto, Portugal.,Instituto Nacional de Engenharia Biomédica (INEB), 4200-135 Porto, Portugal
| | - Helder Maiato
- Instituto de Investigação e Inovação em Saúde (i3S), 4200-135 Porto, Portugal.,Instituto de Biologia Celular e Molecular (IBMC), 4200-135 Porto, Portugal.,Departamento de Biomedicina, Faculdade de Medicina do Porto, 4200-450 Porto, Portugal
| | - Jorge G Ferreira
- Instituto de Investigação e Inovação em Saúde (i3S), 4200-135 Porto, Portugal.,Instituto de Biologia Celular e Molecular (IBMC), 4200-135 Porto, Portugal.,Departamento de Biomedicina, Faculdade de Medicina do Porto, 4200-450 Porto, Portugal
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14
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Synthesis and bioevaluation of new vascular-targeting and anti-angiogenic thieno[2,3-d]pyrimidin-4(3H)-ones. Eur J Med Chem 2020; 189:112060. [PMID: 31958738 DOI: 10.1016/j.ejmech.2020.112060] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2019] [Revised: 01/08/2020] [Accepted: 01/08/2020] [Indexed: 01/08/2023]
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15
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Investigation of the Electrical Properties of Microtubule Ensembles under Cell-Like Conditions. NANOMATERIALS 2020; 10:nano10020265. [PMID: 32033331 PMCID: PMC7075204 DOI: 10.3390/nano10020265] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/04/2019] [Revised: 01/28/2020] [Accepted: 01/29/2020] [Indexed: 01/01/2023]
Abstract
Microtubules are hollow cylindrical polymers composed of the highly negatively-charged (~23e), high dipole moment (1750 D) protein α, β- tubulin. While the roles of microtubules in chromosomal segregation, macromolecular transport, and cell migration are relatively well-understood, studies on the electrical properties of microtubules have only recently gained strong interest. Here, we show that while microtubules at physiological concentrations increase solution capacitance, free tubulin has no appreciable effect. Further, we observed a decrease in electrical resistance of solution, with charge transport peaking between 20-60 Hz in the presence of microtubules, consistent with recent findings that microtubules exhibit electric oscillations at such low frequencies. We were able to quantify the capacitance and resistance of the microtubules (MT) network at physiological tubulin concentrations to be 1.27 × 10-5 F and 9.74 × 104 Ω. Our results show that in addition to macromolecular transport, microtubules also act as charge storage devices through counterionic condensation across a broad frequency spectrum. We conclude with a hypothesis of an electrically tunable cytoskeleton where the dielectric properties of tubulin are polymerisation-state dependent.
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16
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Leung JC, Cassimeris L. Reorganization of paclitaxel-stabilized microtubule arrays at mitotic entry: roles of depolymerizing kinesins and severing proteins. Cancer Biol Ther 2019; 20:1337-1347. [PMID: 31345098 PMCID: PMC6783116 DOI: 10.1080/15384047.2019.1638678] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Paclitaxel is a widely used anti-cancer treatment that disrupts cell cycle progression by blocking cells in mitosis. The block at mitosis, with spindles assembled from short microtubules, is surprising given paclitaxel’s microtubule stabilizing activity and the need to depolymerize long interphase microtubules prior to spindle formation. Cells must antagonize paclitaxel’s microtubule stabilizing activity during a brief window of time at the transition from interphase to mitosis, allowing microtubule reorganization into a mitotic spindle, although the mechanism underlying microtubule depolymerization in the presence of paclitaxel has not been examined. Here we test the hypothesis that microtubule severing and/or depolymerizing proteins active at mitotic entry are necessary to clear the interphase array in paclitaxel-treated cells and allow subsequent formation of mitotic spindles formed of short microtubules. A549 and LLC-PK1 cells treated with 30nM paclitaxel approximately 4 h prior to mitotic entry successfully progress through the G2/M transition by clearing the interphase microtubule array from the cell interior outward to the cell periphery, a spatial pattern of reorganization that differs from that of cells possessing dynamic microtubules. Depletion of kinesin-8s, KIF18A and/or KIF18B obstructed interphase microtubule clearing at mitotic entry in paclitaxel-treated cells, with KIF18B making the larger contribution. Of the severing proteins, depletion of spastin, but not katanin, reduced microtubule loss as cells entered mitosis in the presence of paclitaxel. These results support a model in which KIF18A, KIF18B, and spastin promote interphase microtubule array disassembly at mitotic entry and can overcome paclitaxel-induced microtubule stability specifically at the G2/M transition.
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Affiliation(s)
- Jessica C Leung
- Department of Biological Sciences, 111 Research Dr. Lehigh University , Bethlehem , PA , USA
| | - Lynne Cassimeris
- Department of Biological Sciences, 111 Research Dr. Lehigh University , Bethlehem , PA , USA
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17
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Liu G, Jiao Y, Huang C, Chang P. Identification of novel and potent small-molecule inhibitors of tubulin with antitumor activities by virtual screening and biological evaluations. J Comput Aided Mol Des 2019; 33:659-664. [DOI: 10.1007/s10822-019-00206-y] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2019] [Accepted: 05/18/2019] [Indexed: 12/23/2022]
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18
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Farina F, Ramkumar N, Brown L, Samandar Eweis D, Anstatt J, Waring T, Bithell J, Scita G, Thery M, Blanchoin L, Zech T, Baum B. Local actin nucleation tunes centrosomal microtubule nucleation during passage through mitosis. EMBO J 2019; 38:e99843. [PMID: 31015335 PMCID: PMC6545563 DOI: 10.15252/embj.201899843] [Citation(s) in RCA: 39] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2018] [Revised: 04/02/2019] [Accepted: 04/04/2019] [Indexed: 12/19/2022] Open
Abstract
Cells going through mitosis undergo precisely timed changes in cell shape and organisation, which serve to ensure the fair partitioning of cellular components into the two daughter cells. These structural changes are driven by changes in actin filament and microtubule dynamics and organisation. While most evidence suggests that the two cytoskeletal systems are remodelled in parallel during mitosis, recent work in interphase cells has implicated the centrosome in both microtubule and actin nucleation, suggesting the potential for regulatory crosstalk between the two systems. Here, by using both in vitro and in vivo assays to study centrosomal actin nucleation as cells pass through mitosis, we show that mitotic exit is accompanied by a burst in cytoplasmic actin filament formation that depends on WASH and the Arp2/3 complex. This leads to the accumulation of actin around centrosomes as cells enter anaphase and to a corresponding reduction in the density of centrosomal microtubules. Taken together, these data suggest that the mitotic regulation of centrosomal WASH and the Arp2/3 complex controls local actin nucleation, which may function to tune the levels of centrosomal microtubules during passage through mitosis.
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Affiliation(s)
- Francesca Farina
- MRC-LMCB, UCL, London, UK
- IPLS, UCL, London, UK
- IFOM, the FIRC Institute of Molecular Oncology, University of Milan, Milan, Italy
- University of Grenoble, Grenoble, France
| | | | - Louise Brown
- Institute of Translational Medicine, Cellular and Molecular Physiology, University of Liverpool, Liverpool, UK
| | | | | | - Thomas Waring
- Institute of Translational Medicine, Cellular and Molecular Physiology, University of Liverpool, Liverpool, UK
| | - Jessica Bithell
- Institute of Translational Medicine, Cellular and Molecular Physiology, University of Liverpool, Liverpool, UK
| | - Giorgio Scita
- IFOM, the FIRC Institute of Molecular Oncology, University of Milan, Milan, Italy
- Department of Oncology and Hemato-Oncology, University of Milan, Milan, Italy
| | | | | | - Tobias Zech
- Institute of Translational Medicine, Cellular and Molecular Physiology, University of Liverpool, Liverpool, UK
| | - Buzz Baum
- MRC-LMCB, UCL, London, UK
- IPLS, UCL, London, UK
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19
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Tarasov VV, Chubarev VN, Ashraf GM, Dostdar SA, Sokolov AV, Melnikova TI, Sologova SS, Grigorevskich EM, Makhmutovа A, Kinzirsky AS, Klochkov SG, Aliev G. How Cancer Cells Resist Chemotherapy: Design and Development of Drugs Targeting Protein-Protein Interactions. Curr Top Med Chem 2019; 19:394-412. [DOI: 10.2174/1568026619666190305130141] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2018] [Revised: 09/20/2018] [Accepted: 11/15/2018] [Indexed: 02/07/2023]
Abstract
Background:Resistance toward chemotherapeutics is one of the main obstacles on the way to effective cancer treatment. Personalization of chemotherapy could improve clinical outcome. However, despite preclinical significance, most of the potential markers have failed to reach clinical practice partially due to the inability of numerous studies to estimate the marker’s impact on resistance properly.Objective:The analysis of drug resistance mechanisms to chemotherapy in cancer cells, and the proposal of study design to identify bona fide markers.Methods:A review of relevant papers in the field. A PubMed search with relevant keywords was used to gather the data. An example of a search request: drug resistance AND cancer AND paclitaxel.Results:We have described a number of drug resistance mechanisms to various chemotherapeutics, as well as markers to underlie the phenomenon. We also proposed a model of a rational-designed study, which could be useful in determining the most promising potential biomarkers.Conclusion:Taking into account the most reasonable biomarkers should dramatically improve clinical outcome by choosing the suitable treatment regimens. However, determining the leading biomarkers, as well as validating of the model, is a work for further investigations.
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Affiliation(s)
- Vadim V. Tarasov
- Sechenov First Moscow State Medical University (Sechenov University), 8-2 Trubetskaya St., Moscow 119991, Russian Federation
| | - Vladimir N. Chubarev
- Sechenov First Moscow State Medical University (Sechenov University), 8-2 Trubetskaya St., Moscow 119991, Russian Federation
| | - Ghulam Md Ashraf
- King Fahd Medical Research Center, King Abdulaziz University, Jeddah, Saudi Arabia
| | - Samira A. Dostdar
- Sechenov First Moscow State Medical University (Sechenov University), 8-2 Trubetskaya St., Moscow 119991, Russian Federation
| | - Alexander V. Sokolov
- Sechenov First Moscow State Medical University (Sechenov University), 8-2 Trubetskaya St., Moscow 119991, Russian Federation
| | - Tatiana I. Melnikova
- Sechenov First Moscow State Medical University (Sechenov University), 8-2 Trubetskaya St., Moscow 119991, Russian Federation
| | - Susanna S. Sologova
- Sechenov First Moscow State Medical University (Sechenov University), 8-2 Trubetskaya St., Moscow 119991, Russian Federation
| | - Ekaterina M. Grigorevskich
- Sechenov First Moscow State Medical University (Sechenov University), 8-2 Trubetskaya St., Moscow 119991, Russian Federation
| | - Alfiya Makhmutovа
- Institute of Physiologically Active Compounds Russian Academy of Sciences, Chernogolovka, 142432, Russian Federation
| | - Alexander S. Kinzirsky
- Institute of Physiologically Active Compounds Russian Academy of Sciences, Chernogolovka, 142432, Russian Federation
| | - Sergey G. Klochkov
- Institute of Physiologically Active Compounds Russian Academy of Sciences, Chernogolovka, 142432, Russian Federation
| | - Gjumrakch Aliev
- Institute of Physiologically Active Compounds Russian Academy of Sciences, Chernogolovka, 142432, Russian Federation
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20
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Kaul R, Risinger AL, Mooberry SL. Microtubule-Targeting Drugs: More than Antimitotics. JOURNAL OF NATURAL PRODUCTS 2019; 82:680-685. [PMID: 30835122 DOI: 10.1021/acs.jnatprod.9b00105] [Citation(s) in RCA: 56] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Nature has yielded numerous compounds that bind to tubulin/microtubules and disrupt microtubule function. Even with the advent of targeted therapies for cancer, natural products and their derivatives that target microtubules are some of the most effective drugs used in the treatment of solid tumors and hematological malignancies. For decades, these drugs were thought to work solely through their ability to inhibit mitosis. Accumulating evidence demonstrates that their actions are much more complex, in that they also have significant effects on microtubules in nondividing cells that inhibit a diverse range of signaling events important for carcinogenesis. The abilities of these drugs to inhibit oncogenic signaling likely underlies their efficacy, especially in solid tumors. In this review, we describe the role of microtubules in cells, the proliferation paradox of cells in culture as compared to cancers in patients, and evidence that microtubule-targeting drugs inhibit cellular signaling pathways important for tumorigenesis. The potential mechanisms behind differences in the clinical indications and efficacy of these natural-product-derived drugs are also discussed. Microtubules are an important target for structurally diverse natural products, and a fuller understanding of the mechanisms of action of these drugs will promote their optimal use.
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21
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Loiodice I, Janson ME, Tavormina P, Schaub S, Bhatt D, Cochran R, Czupryna J, Fu C, Tran PT. Quantifying Tubulin Concentration and Microtubule Number Throughout the Fission Yeast Cell Cycle. Biomolecules 2019; 9:biom9030086. [PMID: 30836700 PMCID: PMC6468777 DOI: 10.3390/biom9030086] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2019] [Accepted: 02/26/2019] [Indexed: 11/16/2022] Open
Abstract
The fission yeast Schizosaccharomyces pombe serves as a good genetic model organism for the molecular dissection of the microtubule (MT) cytoskeleton. However, analysis of the number and distribution of individual MTs throughout the cell cycle, particularly during mitosis, in living cells is still lacking, making quantitative modelling imprecise. We use quantitative fluorescent imaging and analysis to measure the changes in tubulin concentration and MT number and distribution throughout the cell cycle at a single MT resolution in living cells. In the wild-type cell, both mother and daughter spindle pole body (SPB) nucleate a maximum of 23 ± 6 MTs at the onset of mitosis, which decreases to a minimum of 4 ± 1 MTs at spindle break down. Interphase MT bundles, astral MT bundles, and the post anaphase array (PAA) microtubules are composed primarily of 1 ± 1 individual MT along their lengths. We measure the cellular concentration of αβ-tubulin subunits to be ~5 µM throughout the cell cycle, of which one-third is in polymer form during interphase and one-quarter is in polymer form during mitosis. This analysis provides a definitive characterization of αβ-tubulin concentration and MT number and distribution in fission yeast and establishes a foundation for future quantitative comparison of mutants defective in MTs.
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Affiliation(s)
- Isabelle Loiodice
- Cell & Developmental Biology, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Marcel E Janson
- Cell & Developmental Biology, University of Pennsylvania, Philadelphia, PA 19104, USA
| | | | - Sebastien Schaub
- Institut Curie, PSL Research University, CNRS, UMR 144, F-75005 Paris, France
| | - Divya Bhatt
- Cell & Developmental Biology, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Ryan Cochran
- Cell & Developmental Biology, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Julie Czupryna
- Cell & Developmental Biology, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Chuanhai Fu
- Cell & Developmental Biology, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Phong T Tran
- Cell & Developmental Biology, University of Pennsylvania, Philadelphia, PA 19104, USA.
- Institut Curie, PSL Research University, CNRS, UMR 144, F-75005 Paris, France.
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22
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Sherin L, Farwa S, Sohail A, Li Z, Bég OA. Cancer drug therapy and stochastic modeling of "nano-motors". Int J Nanomedicine 2018; 13:6429-6440. [PMID: 30410329 PMCID: PMC6198871 DOI: 10.2147/ijn.s168780] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Background Controlled inhibition of kinesin motor proteins is highly desired in the field of oncology. Among other interventions, there exists “targeted chemotherapeutic regime/options” of selective Eg5 competitive and allosteric inhibitors, inducing cancer cell apoptosis and tumor regression with improved safety profiles. Research question Though promising, such studies are still under clinical trials, for the discovery of efficient and least harmful Eg5 inhibitors. The aim of this research was to bridge the computational modeling approach with drug design and therapy of cancer cells. Methods A computational model, interfaced with the clinical data of “Eg5 dynamics” and “inhibitors” via special functions, is presented in this article. Comparisons are made for the drug efficacy, and the threshold values are predicted through numerical simulations. Results Results are obtained to depict the dynamics induced by ispinesib, when used as an inhibitor of kinesin Eg5, on cancer cell lines.
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Affiliation(s)
- Lubna Sherin
- Department of Chemistry, COMSATS University Islamabad, Lahore 54000, Pakistan
| | - Shabieh Farwa
- Department of Mathematics, COMSATS University Islamabad, Wah Cantt, Pakistan
| | - Ayesha Sohail
- Department of Mathematics, COMSATS University Islamabad, Lahore 54000, Pakistan,
| | - Zhiwu Li
- Institute of Systems Engineering, Macau University of Science and Technology, Taipa, Macau.,School of Electro-Mechanical Engineering, Xidian University, Xi'an 710071, China
| | - O Anwar Bég
- Fluid Mechanics, Spray Research Group, Mechanical and Petroleum Engineering, School of Computing, Science and Engineering, G77, University of Salford, Manchester M54WT, UK
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23
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Cassimeris L, Leung JC, Odde DJ. Monte Carlo simulations of microtubule arrays: The critical roles of rescue transitions, the cell boundary, and tubulin concentration in shaping microtubule distributions. PLoS One 2018; 13:e0197538. [PMID: 29782540 PMCID: PMC5962052 DOI: 10.1371/journal.pone.0197538] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2018] [Accepted: 05/03/2018] [Indexed: 01/12/2023] Open
Abstract
Microtubules are dynamic polymers required for a number of processes, including chromosome movement in mitosis. While regulators of microtubule dynamics have been well characterized, we lack a convenient way to predict how the measured dynamic parameters shape the entire microtubule system within a cell, or how the system responds when specific parameters change in response to internal or external signals. Here we describe a Monte Carlo model to simulate an array of dynamic microtubules from parameters including the cell radius, total tubulin concentration, microtubule nucleation rate from the centrosome, and plus end dynamic instability. The algorithm also allows dynamic instability or position of the cell edge to vary during the simulation. Outputs from simulations include free tubulin concentration, average microtubule lengths, length distributions, and individual length changes over time. Using this platform and reported parameters measured in interphase LLCPK1 epithelial cells, we predict that sequestering ~ 15-20% of total tubulin results in fewer microtubules, but promotes dynamic instability of those remaining. Simulations also predict that lowering nucleation rate will increase the stability and average length of the remaining microtubules. Allowing the position of the cell's edge to vary over time changed the average length but not the number of microtubules and generated length distributions consistent with experimental measurements. Simulating the switch from interphase to prophase demonstrated that decreased rescue frequency at prophase is the critical factor needed to rapidly clear the cell of interphase microtubules prior to mitotic spindle assembly. Finally, consistent with several previous simulations, our results demonstrate that microtubule nucleation and dynamic instability in a confined space determines the partitioning of tubulin between monomer and polymer pools. The model and simulations will be useful for predicting changes to the entire microtubule array after modification to one or more parameters, including predicting the effects of tubulin-targeted chemotherapies.
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Affiliation(s)
- Lynne Cassimeris
- Dept. of Biological Sciences, Lehigh University, Bethlehem, Pennsylvania, United States of America
| | - Jessica C Leung
- Dept. of Biological Sciences, Lehigh University, Bethlehem, Pennsylvania, United States of America
| | - David J Odde
- Dept. of Biomedical Engineering, University of Minnesota, Minneapolis, Minnesota, United States of America
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24
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Osseman Q, Gallucci L, Au S, Cazenave C, Berdance E, Blondot ML, Cassany A, Bégu D, Ragues J, Aknin C, Sominskaya I, Dishlers A, Rabe B, Anderson F, Panté N, Kann M. The chaperone dynein LL1 mediates cytoplasmic transport of empty and mature hepatitis B virus capsids. J Hepatol 2018; 68:441-448. [PMID: 29113909 DOI: 10.1016/j.jhep.2017.10.032] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/22/2017] [Revised: 09/26/2017] [Accepted: 10/27/2017] [Indexed: 02/08/2023]
Abstract
BACKGROUND & AIMS Hepatitis B virus (HBV) has a DNA genome but replicates within the nucleus by reverse transcription of an RNA pregenome, which is converted to DNA in cytoplasmic capsids. Capsids in this compartment are correlated with inflammation and epitopes of the capsid protein core (Cp) are a major target for T cell-mediated immune responses. We investigated the mechanism of cytoplasmic capsid transport, which is important for infection but also for cytosolic capsid removal. METHODS We used virion-derived capsids containing mature rcDNA (matC) and empty capsids (empC). RNA-containing capsids (rnaC) were used as a control. The investigations comprised pull-down assays for identification of cellular interaction partners, immune fluorescence microscopy for their colocalization and electron microscopy after microinjection to determine their biological significance. RESULTS matC and empC underwent active transport through the cytoplasm towards the nucleus, while rnaC was poorly transported. We identified the dynein light chain LL1 as a functional interaction partner linking capsids to the dynein motor complex and showed that there is no compensatory transport pathway. Using capsid and dynein LL1 mutants we characterized the required domains on the capsid and LL1. CONCLUSIONS This is the first investigation on the detailed molecular mechanism of how matC pass the cytoplasm upon infection and how empC can be actively removed from the cytoplasm into the nucleus. Considering that hepatocytes with cytoplasmic capsids are better recognized by the T cells, we hypothesize that targeting capsid DynLL1-interaction will not only block HBV infection but also stimulate elimination of infected cells. LAY SUMMARY In this study, we identified the molecular details of HBV translocation through the cytoplasm. Our evidence offers a new drug target which could not only inhibit infection but also stimulate immune clearance of HBV infected cells.
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Affiliation(s)
- Quentin Osseman
- Univ. de Bordeaux, Microbiologie Fondamentale et Pathogénicité, UMR 5234, 33076 Bordeaux, France; CNRS, Microbiologie Fondamentale et Pathogénicité, UMR 5234, Bordeaux, France
| | - Lara Gallucci
- Univ. de Bordeaux, Microbiologie Fondamentale et Pathogénicité, UMR 5234, 33076 Bordeaux, France; CNRS, Microbiologie Fondamentale et Pathogénicité, UMR 5234, Bordeaux, France
| | - Shelly Au
- Department of Zoology, University of British Columbia Vancouver, B.C. V6T 1Z4, Canada
| | - Christian Cazenave
- Univ. de Bordeaux, Microbiologie Fondamentale et Pathogénicité, UMR 5234, 33076 Bordeaux, France; CNRS, Microbiologie Fondamentale et Pathogénicité, UMR 5234, Bordeaux, France
| | - Elodie Berdance
- Univ. de Bordeaux, Microbiologie Fondamentale et Pathogénicité, UMR 5234, 33076 Bordeaux, France; CNRS, Microbiologie Fondamentale et Pathogénicité, UMR 5234, Bordeaux, France
| | - Marie-Lise Blondot
- Univ. de Bordeaux, Microbiologie Fondamentale et Pathogénicité, UMR 5234, 33076 Bordeaux, France; CNRS, Microbiologie Fondamentale et Pathogénicité, UMR 5234, Bordeaux, France
| | - Aurélia Cassany
- Univ. de Bordeaux, Microbiologie Fondamentale et Pathogénicité, UMR 5234, 33076 Bordeaux, France; CNRS, Microbiologie Fondamentale et Pathogénicité, UMR 5234, Bordeaux, France
| | - Dominique Bégu
- Univ. de Bordeaux, Microbiologie Fondamentale et Pathogénicité, UMR 5234, 33076 Bordeaux, France; CNRS, Microbiologie Fondamentale et Pathogénicité, UMR 5234, Bordeaux, France
| | - Jessica Ragues
- Univ. de Bordeaux, Microbiologie Fondamentale et Pathogénicité, UMR 5234, 33076 Bordeaux, France; CNRS, Microbiologie Fondamentale et Pathogénicité, UMR 5234, Bordeaux, France
| | - Cindy Aknin
- Univ. de Bordeaux, Microbiologie Fondamentale et Pathogénicité, UMR 5234, 33076 Bordeaux, France; CNRS, Microbiologie Fondamentale et Pathogénicité, UMR 5234, Bordeaux, France
| | | | - Andris Dishlers
- Latvian Biomedical Research and Study Center, 1067 Riga, Latvia
| | - Birgit Rabe
- Institute of Medical Virology, University of Giessen, 35392 Giessen, Germany
| | - Fenja Anderson
- Institute of Medical Virology, University of Giessen, 35392 Giessen, Germany; Institute of Virology, Hannover Medical School, 30625 Hannover, Germany
| | - Nelly Panté
- Department of Zoology, University of British Columbia Vancouver, B.C. V6T 1Z4, Canada
| | - Michael Kann
- Univ. de Bordeaux, Microbiologie Fondamentale et Pathogénicité, UMR 5234, 33076 Bordeaux, France; CNRS, Microbiologie Fondamentale et Pathogénicité, UMR 5234, Bordeaux, France; Institute of Medical Virology, University of Giessen, 35392 Giessen, Germany; CHU de Bordeaux, 33000 Bordeaux, France.
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25
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Kolenda C, Ortiz J, Pelzl M, Norell S, Schmeiser V, Lechner J. Unattached kinetochores drive their own capturing by sequestering a CLASP. Nat Commun 2018; 9:886. [PMID: 29491436 PMCID: PMC5830412 DOI: 10.1038/s41467-018-03108-z] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2017] [Accepted: 01/17/2018] [Indexed: 12/24/2022] Open
Abstract
Kinetochores that are not attached to microtubules prevent chromosome missegregation via the spindle assembly checkpoint. We show that they also promote their own capturing. Similar to what governs the localization of spindle assembly checkpoint proteins, the phosphorylation of Spc105 by Mps1 allows unattached kinetochores to sequester Stu1 in cooperation with Slk19. The withdrawal of Stu1, a CLASP essential for spindle integrity, from microtubules and attached kinetochores disrupts the organization of the spindle and thus allows the enhanced formation of dynamic random microtubules that span the nucleus and are ideal to capture unattached kinetochores. The enhanced formation of nuclear random microtubules does not occur if Stu1 sequestering to unattached kinetochores fails and the spindle remains uncompromised. Consequently, these cells exhibit a severely decreased capturing efficiency. After the capturing event, Stu1 is relocated to the capturing microtubule and prevents precocious microtubule depolymerization as long as kinetochores are laterally or incompletely end-on attached. Kinetochores (KT) that are not attached to microtubules prevent chromosome missegregation via the spindle assembly checkpoint. Here the authors show that Mps1 localizes Stu1 at unattached KTs together with Slk19, causing a reorganization of the nuclear MT network that favors the capturing of unattached KT.
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Affiliation(s)
- Caroline Kolenda
- Biochemie-Zentrum der Universität Heidelberg, INF 328, 69120, Heidelberg, Germany
| | - Jennifer Ortiz
- Biochemie-Zentrum der Universität Heidelberg, INF 328, 69120, Heidelberg, Germany
| | - Marina Pelzl
- Biochemie-Zentrum der Universität Heidelberg, INF 328, 69120, Heidelberg, Germany
| | - Sarina Norell
- Biochemie-Zentrum der Universität Heidelberg, INF 328, 69120, Heidelberg, Germany
| | - Verena Schmeiser
- Biochemie-Zentrum der Universität Heidelberg, INF 328, 69120, Heidelberg, Germany
| | - Johannes Lechner
- Biochemie-Zentrum der Universität Heidelberg, INF 328, 69120, Heidelberg, Germany.
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Mchedlishvili N, Matthews HK, Corrigan A, Baum B. Two-step interphase microtubule disassembly aids spindle morphogenesis. BMC Biol 2018; 16:14. [PMID: 29361957 PMCID: PMC5778756 DOI: 10.1186/s12915-017-0478-z] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2017] [Accepted: 12/22/2017] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Entry into mitosis triggers profound changes in cell shape and cytoskeletal organisation. Here, by studying microtubule remodelling in human flat mitotic cells, we identify a two-step process of interphase microtubule disassembly. RESULTS First, a microtubule-stabilising protein, Ensconsin/MAP7, is inactivated in prophase as a consequence of its phosphorylation downstream of Cdk1/cyclin B. This leads to a reduction in interphase microtubule stability that may help to fuel the growth of centrosomally nucleated microtubules. The peripheral interphase microtubules that remain are then rapidly lost as the concentration of tubulin heterodimers falls following dissolution of the nuclear compartment boundary. Finally, we show that a failure to destabilise microtubules in prophase leads to the formation of microtubule clumps, which interfere with spindle assembly. CONCLUSIONS This analysis highlights the importance of the step-wise remodelling of the microtubule cytoskeleton and the significance of permeabilisation of the nuclear envelope in coordinating the changes in cellular organisation and biochemistry that accompany mitotic entry.
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Affiliation(s)
- Nunu Mchedlishvili
- MRC Laboratory of Molecular Cell Biology and the IPLS, University College London, Gower Street, London, WC1E 6BT, UK
| | - Helen K Matthews
- MRC Laboratory of Molecular Cell Biology and the IPLS, University College London, Gower Street, London, WC1E 6BT, UK
| | - Adam Corrigan
- MRC Laboratory of Molecular Cell Biology and the IPLS, University College London, Gower Street, London, WC1E 6BT, UK
| | - Buzz Baum
- MRC Laboratory of Molecular Cell Biology and the IPLS, University College London, Gower Street, London, WC1E 6BT, UK.
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27
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Vaseghi G, Taki MJ, Javanmard SH. Standardized Cannabis sativa extract attenuates tau and stathmin gene expression in the melanoma cell line. IRANIAN JOURNAL OF BASIC MEDICAL SCIENCES 2017; 20:1178-1181. [PMID: 29147495 PMCID: PMC5673704 DOI: 10.22038/ijbms.2017.9398] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/02/2022]
Abstract
Objective(s): Metastasis is the main cause of death in patients with melanoma. Cannabis-based medicines are effective adjunctive drugs in cancer patients. Tau and Stathmin proteins are the key proteins in cancer metastasis. Here we have investigated the effect of a standardized Cannabis sativa extract on cell migration and Tau and Stathmin gene expression in the melanoma cell line. Materials and Methods: In the treatment group, melanoma (B1617) was treated 48 hr with various concentrations of standardized C. sativa extract. Cells with no treatment were considered as the control group, then study was followed by Quantitative RT-Real Time PCR assay. Relative gene expression was calculated by the ΔΔct method. Migration assay was used to evaluate cancer metastasis. Results: Tau and stathmin gene expression was significantly decreased compared to the control group. Cell migration was also significantly reduced compared to controls. Conclusion: C. sativa decreased tau and stathmin gene expression and cancer metastasis. The results may have some clinical relevance for the use of cannabis-based medicines in patients with metastatic melanoma.
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Affiliation(s)
- Golnaz Vaseghi
- Isfahan Cardiovascular Research Center, Cardiovascular Research Institute, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Mohamad Javad Taki
- Applied Physiology Research Center, Cardiovascular Research Institute, Department of Physiology, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Shaghayegh Haghjooy Javanmard
- Applied Physiology Research Center, Cardiovascular Research Institute, Department of Physiology, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran
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28
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Vleugel M, Kok M, Dogterom M. Understanding force-generating microtubule systems through in vitro reconstitution. Cell Adh Migr 2017; 10:475-494. [PMID: 27715396 PMCID: PMC5079405 DOI: 10.1080/19336918.2016.1241923] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022] Open
Abstract
Microtubules switch between growing and shrinking states, a feature known as dynamic instability. The biochemical parameters underlying dynamic instability are modulated by a wide variety of microtubule-associated proteins that enable the strict control of microtubule dynamics in cells. The forces generated by controlled growth and shrinkage of microtubules drive a large range of processes, including organelle positioning, mitotic spindle assembly, and chromosome segregation. In the past decade, our understanding of microtubule dynamics and microtubule force generation has progressed significantly. Here, we review the microtubule-intrinsic process of dynamic instability, the effect of external factors on this process, and how the resulting forces act on various biological systems. Recently, reconstitution-based approaches have strongly benefited from extensive biochemical and biophysical characterization of individual components that are involved in regulating or transmitting microtubule-driven forces. We will focus on the current state of reconstituting increasingly complex biological systems and provide new directions for future developments.
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Affiliation(s)
- Mathijs Vleugel
- a Department of Bionanoscience , Kavli Institute of Nanoscience, Faculty of Applied Sciences, Delft Institute of Technology , Delft , The Netherlands
| | - Maurits Kok
- a Department of Bionanoscience , Kavli Institute of Nanoscience, Faculty of Applied Sciences, Delft Institute of Technology , Delft , The Netherlands
| | - Marileen Dogterom
- a Department of Bionanoscience , Kavli Institute of Nanoscience, Faculty of Applied Sciences, Delft Institute of Technology , Delft , The Netherlands
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29
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Kapoor TM. Metaphase Spindle Assembly. BIOLOGY 2017; 6:biology6010008. [PMID: 28165376 PMCID: PMC5372001 DOI: 10.3390/biology6010008] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/03/2016] [Revised: 01/17/2017] [Accepted: 01/19/2017] [Indexed: 01/31/2023]
Abstract
A microtubule-based bipolar spindle is required for error-free chromosome segregation during cell division. In this review I discuss the molecular mechanisms required for the assembly of this dynamic micrometer-scale structure in animal cells.
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Affiliation(s)
- Tarun M Kapoor
- Laboratory of Chemistry and Cell Biology, the Rockefeller University, New York, NY 10065, USA.
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30
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Abstract
The early steps of HBV entry remain largely unknown despite the recent discovery of an HBV-specific entry receptor. Following entry HBV capsids have to be transported through the cytoplasm to the nuclear periphery, followed by nuclear entry. These steps have to take place in a coordinated manner to allow delivery of the genome into the nucleus. Due to the viscosity of the cytoplasm, the intracytoplasmic translocation has to be active and directed.Here, we describe protocols that can be applied to investigations of the HBV capsid with the cytoplasmic transport systems. We have chosen to present two independent experimental approaches, which allow avoiding artifacts. Aside of the specific capsid detection system, the protocols can be applied to any other viral structure.
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Affiliation(s)
- Quentin Osseman
- University of Bordeaux, Microbiologie Fondamentale et Pathogénicité, UMR 5234, Bordeaux, France
- CNRS, Microbiologie Fondamentale et Pathogénicité, UMR 5234, Bordeaux, France
| | - Michael Kann
- University of Bordeaux, Microbiologie Fondamentale et Pathogénicité, UMR 5234, Bordeaux, France.
- CNRS, Microbiologie Fondamentale et Pathogénicité, UMR 5234, Bordeaux, France.
- Centre Hospitalier Universitaire de Bordeaux, Service de Virologie, Bordeaux, France.
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31
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Scholey JM, Civelekoglu-Scholey G, Brust-Mascher I. Anaphase B. BIOLOGY 2016; 5:biology5040051. [PMID: 27941648 PMCID: PMC5192431 DOI: 10.3390/biology5040051] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/28/2016] [Revised: 11/30/2016] [Accepted: 12/01/2016] [Indexed: 11/16/2022]
Abstract
Anaphase B spindle elongation is characterized by the sliding apart of overlapping antiparallel interpolar (ip) microtubules (MTs) as the two opposite spindle poles separate, pulling along disjoined sister chromatids, thereby contributing to chromosome segregation and the propagation of all cellular life. The major biochemical “modules” that cooperate to mediate pole–pole separation include: (i) midzone pushing or (ii) braking by MT crosslinkers, such as kinesin-5 motors, which facilitate or restrict the outward sliding of antiparallel interpolar MTs (ipMTs); (iii) cortical pulling by disassembling astral MTs (aMTs) and/or dynein motors that pull aMTs outwards; (iv) ipMT plus end dynamics, notably net polymerization; and (v) ipMT minus end depolymerization manifest as poleward flux. The differential combination of these modules in different cell types produces diversity in the anaphase B mechanism. Combinations of antagonist modules can create a force balance that maintains the dynamic pre-anaphase B spindle at constant length. Tipping such a force balance at anaphase B onset can initiate and control the rate of spindle elongation. The activities of the basic motor filament components of the anaphase B machinery are controlled by a network of non-motor MT-associated proteins (MAPs), for example the key MT cross-linker, Ase1p/PRC1, and various cell-cycle kinases, phosphatases, and proteases. This review focuses on the molecular mechanisms of anaphase B spindle elongation in eukaryotic cells and briefly mentions bacterial DNA segregation systems that operate by spindle elongation.
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Affiliation(s)
- Jonathan M Scholey
- Department of Molecular and Cell Biology, University of California, Davis, CA 95616, USA.
| | | | - Ingrid Brust-Mascher
- Department of Anatomy, Physiology and Cell Biology, School of Veterinary Medicine, University of California, Davis, CA 95616, USA.
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32
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Brice A, Whelan DR, Ito N, Shimizu K, Wiltzer-Bach L, Lo CY, Blondel D, Jans DA, Bell TDM, Moseley GW. Quantitative Analysis of the Microtubule Interaction of Rabies Virus P3 Protein: Roles in Immune Evasion and Pathogenesis. Sci Rep 2016; 6:33493. [PMID: 27649849 PMCID: PMC5030706 DOI: 10.1038/srep33493] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2016] [Accepted: 08/25/2016] [Indexed: 12/21/2022] Open
Abstract
Although microtubules (MTs) are known to have important roles in intracellular transport of many viruses, a number of reports suggest that specific viral MT-associated proteins (MAPs) target MTs to subvert distinct MT-dependent cellular processes. The precise functional importance of these interactions and their roles in pathogenesis, however, remain largely unresolved. To assess the association with disease of the rabies virus (RABV) MAP, P3, we quantitatively compared the phenotypes of P3 from a pathogenic RABV strain, Nishigahara (Ni) and a non-pathogenic Ni-derivative strain, Ni-CE. Using confocal/live-cell imaging and dSTORM super-resolution microscopy to quantify protein interactions with the MT network and with individual MT filaments, we found that the interaction by Ni-CE-P3 is significantly impaired compared with Ni-P3. This correlated with an impaired capacity to effect association of the transcription factor STAT1 with MTs and to antagonize interferon (IFN)/STAT1-dependent antiviral signaling. Importantly, we identified a single mutation in Ni-CE-P3 that is sufficient to inhibit MT-association and IFN-antagonist function of Ni-P3, and showed that this mutation alone attenuates the pathogenicity of RABV. These data provide evidence that the viral protein-MT interface has important roles in pathogenesis, suggesting that this interface could provide targets for vaccine/antiviral drug development.
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Affiliation(s)
- Aaron Brice
- Viral Pathogenesis Laboratory, Department of Biochemistry and Molecular Biology, Bio21 Institute, The University of Melbourne, Melbourne, Victoria, 3010, Australia
| | - Donna R Whelan
- School of Chemistry, Monash University, Clayton, Victoria 3800, Australia
| | - Naoto Ito
- Laboratory of Zoonotic Diseases, Faculty of Applied Biological Sciences, Gifu University, 1-1 Yanagido, Gifu 501-1193, Japan.,The United Graduate School of Veterinary Sciences, Gifu University, 1-1 Yanagido, Gifu 501-1193, Japan
| | - Kenta Shimizu
- The United Graduate School of Veterinary Sciences, Gifu University, 1-1 Yanagido, Gifu 501-1193, Japan
| | - Linda Wiltzer-Bach
- Nuclear Signaling Laboratory, Department of Biochemistry and Molecular Biology, Monash University, Clayton, Victoria 3800, Australia.,Viral Pathogenesis Laboratory, Department of Biochemistry and Molecular Biology, Monash University, Clayton, Victoria 3800, Australia
| | - Camden Y Lo
- Monash Micro Imaging, 27-31 Wright Street, Clayton, Victoria, 3168, Australia
| | - Danielle Blondel
- Unité de Virologie Moleculaire et Structurale, CNRS, UPR 3296, 91198 Gif sur Yvette Cedex, France
| | - David A Jans
- Nuclear Signaling Laboratory, Department of Biochemistry and Molecular Biology, Monash University, Clayton, Victoria 3800, Australia
| | - Toby D M Bell
- School of Chemistry, Monash University, Clayton, Victoria 3800, Australia
| | - Gregory W Moseley
- Viral Pathogenesis Laboratory, Department of Biochemistry and Molecular Biology, Bio21 Institute, The University of Melbourne, Melbourne, Victoria, 3010, Australia
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33
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Kent IA, Lele TP. Microtubule-based force generation. WILEY INTERDISCIPLINARY REVIEWS-NANOMEDICINE AND NANOBIOTECHNOLOGY 2016; 9. [PMID: 27562344 DOI: 10.1002/wnan.1428] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/17/2016] [Revised: 07/20/2016] [Accepted: 07/30/2016] [Indexed: 11/11/2022]
Abstract
Microtubules are vital to many important cell processes, such as cell division, transport of cellular cargo, organelle positioning, and cell migration. Owing to their diverse functions, understanding microtubule function is an important part of cell biological research that can help in combating various diseases. For example, microtubules are an important target of chemotherapeutic drugs such as paclitaxel because of their pivotal role in cell division. Many functions of microtubules relate to the generation of mechanical forces. These forces are generally either a direct result of microtubule polymerization/depolymerization or generated by motor proteins that move processively along microtubules. In this review, we summarize recent efforts to quantify and model force generation by microtubules in the context of microtubule function. WIREs Nanomed Nanobiotechnol 2017, 9:e1428. doi: 10.1002/wnan.1428 For further resources related to this article, please visit the WIREs website.
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Affiliation(s)
- Ian A Kent
- Department of Chemical Engineering, University of Florida, Gainesville, FL, USA
| | - Tanmay P Lele
- Department of Chemical Engineering, University of Florida, Gainesville, FL, USA
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34
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Abstract
Animal cells undergo dramatic changes in shape, mechanics and polarity as they progress through the different stages of cell division. These changes begin at mitotic entry, with cell-substrate adhesion remodelling, assembly of a cortical actomyosin network and osmotic swelling, which together enable cells to adopt a near spherical form even when growing in a crowded tissue environment. These shape changes, which probably aid spindle assembly and positioning, are then reversed at mitotic exit to restore the interphase cell morphology. Here, we discuss the dynamics, regulation and function of these processes, and how cell shape changes and sister chromatid segregation are coupled to ensure that the daughter cells generated through division receive their fair inheritance.
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35
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Inhibition of microtubule dynamics impedes repair of kidney ischemia/reperfusion injury and increases fibrosis. Sci Rep 2016; 6:27775. [PMID: 27270990 PMCID: PMC4897697 DOI: 10.1038/srep27775] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2016] [Accepted: 05/23/2016] [Indexed: 11/08/2022] Open
Abstract
The microtubule cytoskeleton is composed of α-tubulin and β-tubulin heterodimers, and it serves to regulate the shape, motility, and division of a cell. Post-translational modifications including acetylation are closely associated with the functional aspects of the microtubule, involving in a number of pathological diseases. However, the role of microtubule acetylation in acute kidney injury (AKI) and progression of AKI to chronic kidney disease have yet to be understood. In this study, ischemia/reperfusion (I/R), a major cause of AKI, resulted in deacetylation of the microtubules with a decrease in α-tubulin acetyltransferase 1 (α-TAT1). Paclitaxel (taxol), an agent that stabilizes microtubules by tubulin acetylation, treatment during the recovery phase following I/R injury inhibited tubular cell proliferation, impaired renal functional recovery, and worsened fibrosis. Taxol induced α-tubulin acetylation and post-I/R cell cycle arrest. Taxol aggregated the microtubule in the cytoplasm, resulting in suppression of microtubule dynamics. Our studies have demonstrated for the first time that I/R induced deacetylation of the microtubules, and that inhibition of microtubule dynamics retarded repair of injured tubular epithelial cells leading to an acceleration of fibrosis. This suggests that microtubule dynamics plays an important role in the processes of repair and fibrosis after AKI.
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36
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Ververis A, Christodoulou A, Christoforou M, Kamilari C, Lederer CW, Santama N. A novel family of katanin-like 2 protein isoforms (KATNAL2), interacting with nucleotide-binding proteins Nubp1 and Nubp2, are key regulators of different MT-based processes in mammalian cells. Cell Mol Life Sci 2016; 73:163-84. [PMID: 26153462 PMCID: PMC11108477 DOI: 10.1007/s00018-015-1980-5] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2015] [Revised: 06/08/2015] [Accepted: 06/25/2015] [Indexed: 11/30/2022]
Abstract
Katanins are microtubule (MT)-severing AAA proteins with high phylogenetic conservation throughout the eukaryotes. They have been functionally implicated in processes requiring MT remodeling, such as spindle assembly in mitosis and meiosis, assembly/disassembly of flagella and cilia and neuronal morphogenesis. Here, we uncover a novel family of katanin-like 2 proteins (KATNAL2) in mouse, consisting of five alternatively spliced isoforms encoded by the Katnal2 genomic locus. We further demonstrate that in vivo these isoforms are able to interact with themselves, with each other and moreover directly and independently with MRP/MinD-type P-loop NTPases Nubp1 and Nubp2, which are integral components of centrioles, negative regulators of ciliogenesis and implicated in centriole duplication in mammalian cells. We find KATNAL2 localized on interphase MTs, centrioles, mitotic spindle, midbody and the axoneme and basal body of sensory cilia in cultured murine cells. shRNAi of Katnal2 results in inefficient cytokinesis and severe phenotypes of enlarged cells and nuclei, increased numbers of centrioles and the manifestation of aberrant multipolar mitotic spindles, mitotic defects, chromosome bridges, multinuclearity, increased MT acetylation and an altered cell cycle pattern. Silencing or stable overexpression of KATNAL2 isoforms drastically reduces ciliogenesis. In conclusion, KATNAL2s are multitasking enzymes involved in the same cell type in critically important processes affecting cytokinesis, MT dynamics, and ciliogenesis and are also implicated in cell cycle progression.
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Affiliation(s)
- Antonis Ververis
- Department of Biological Sciences, University of Cyprus, University Avenue 1, 1678, Nicosia, Cyprus
| | - Andri Christodoulou
- Department of Biological Sciences, University of Cyprus, University Avenue 1, 1678, Nicosia, Cyprus
| | - Maria Christoforou
- Department of Biological Sciences, University of Cyprus, University Avenue 1, 1678, Nicosia, Cyprus
| | - Christina Kamilari
- Department of Biological Sciences, University of Cyprus, University Avenue 1, 1678, Nicosia, Cyprus
| | | | - Niovi Santama
- Department of Biological Sciences, University of Cyprus, University Avenue 1, 1678, Nicosia, Cyprus.
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37
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Liu J, Han R. The Evolution of Microtubule End-Binding Protein 1 (EB1) and Roles in Regulating Microtubule Behavior. ACTA ACUST UNITED AC 2015. [DOI: 10.4236/ajps.2015.613212] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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38
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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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39
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Avidor-Reiss T, Gopalakrishnan J. Cell Cycle Regulation of the Centrosome and Cilium. ACTA ACUST UNITED AC 2013; 10:e119-e124. [PMID: 24982683 DOI: 10.1016/j.ddmec.2013.03.002] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Centrosomes and cilia are conserved microtubule-based organelles whose structure and function depend on cell cycle stages. In dividing cells, centrosomes organize mitotic spindle poles, while in differentiating cells, centrosomes template ciliogenesis. Classically, this functional dichotomy has been attributed to regulation by cell cycle-dependent post-translational modifications, and recently PLK1, Nek2, Aurora A, and tubulin deacetylase were implicated in regulating the transition from cilia to centrosome. However, other recent studies suggest that tubulin dimers, the core structural components of centrosomes and cilia, also have a regulatory role. These regulatory mechanisms can be a target for chemotherapeutic intervention.
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Affiliation(s)
- Tomer Avidor-Reiss
- Department of Biological Sciences, University of Toledo, Toledo, OH 43606, USA
| | - Jayachandran Gopalakrishnan
- Center for Molecular Medicine, University of Cologne, Germany ; Institute of Biochemistry I, University of Cologne, Germany
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40
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Abro A, Kulsoom S, Riaz N. Pharmacophore model generation for microtubule-stabilizing anti-mitotic agents (MSAAs) against ovarian cancer. Med Chem Res 2013. [DOI: 10.1007/s00044-012-0445-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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41
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Microtubule-associated protein tau facilitates the targeted killing of proliferating cancer cells in vitro and in a xenograft mouse tumour model in vivo. Br J Cancer 2013; 109:1570-8. [PMID: 23942071 PMCID: PMC3776980 DOI: 10.1038/bjc.2013.457] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2013] [Revised: 07/18/2013] [Accepted: 07/22/2013] [Indexed: 01/01/2023] Open
Abstract
Background: Antibody drug conjugates (ADCs) and immunotoxins (ITs) are promising anticancer immunotherapeutics. Despite their encouraging performance in clinical trials, both ADCs and ITs often suffer from disadvantages such as stoichiometrically undefined chemical linkage of the cytotoxic payload (ADCs) and the potential immunogenicity of toxins derived from bacteria and plants (ITs). Methods: Human microtubule-associated protein tau (MAP) was cloned in-frame with human EGF, expressed in E. coli and purified by standard chromatographic methods. The in vitro activity was confirmed by flow cytometry, cell viability assays and tubulin polymerisation assay. The in vivo efficacy was demonstrated using noninvasive far-red in vivo imaging. Results: The EGF-MAP selectively induced apoptosis in EGFR-overexpressing proliferating cancer cells through stabilisation of microtubules. Nonproliferating cells were not affected, demonstrating superior selectivity of EGF-MAP for cancer cells. The EGF-MAP was well tolerated at high doses in mice compared with the ETA'-based control. The in vivo efficacy of EGF-MAP was demonstrated in a tumour xenograft mouse model. Conclusion: Our data indicate the general mechanism of action for a new class of human immunotherapeutic reagents suitable for the treatment of cancer. This approach combines the binding specificity of targeting ligands with the selective cytotoxicity of MAP towards proliferating cells.
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42
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Park J, Rhee K. NEK2 phosphorylation antagonizes the microtubule stabilizing activity of centrobin. Biochem Biophys Res Commun 2013; 431:302-8. [PMID: 23291182 DOI: 10.1016/j.bbrc.2012.12.106] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2012] [Accepted: 12/18/2012] [Indexed: 12/13/2022]
Abstract
Centrobin was initially identified as a centrosome protein for centriole duplication. Centrobin is also detected outside the centrosome and involved in other cellular functions, such as spindle assembly. We previously reported that centrobin is a substrate of both NEK2 and PLK1, but it is not clear what functional properties of centrobin are regulated by two kinases. Here, we report that centrobin is involved in cell spreading, migration and microtubule stabilization in interphase cells. The NEK2-depleted cells looked spread with well-developed microtubule networks and migrated faster than the control cells. The microtubule stability in NEK2-depleted cells was higher than the control cells. However, the opposite was the case in centrobin-depleted cells. The opposite outcomes in NEK2- and centrobin-depleted cells suggest that NEK2 antagonizes biological functions of centrobin. We identified NEK2 phosphorylation sites within centrobin, which is distinct from the PLK1 phosphorylation sites. In fact, the phospho-resistant mutant of centrobin against NEK2 stabilized microtubule networks in vivo. Based on the results, we propose that NEK2 phosphorylation antagonizes the microtubule stabilizing activity of centrobin. Centrobin is a novel example that NEK2 and PLK1 independently phosphorylate a substrate and result in opposite outcomes in substrate function.
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Affiliation(s)
- Joonhyun Park
- Department of Biological Sciences, Seoul National University, Seoul 151-747, Republic of Korea
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Hasegawa K, Ryu SJ, Kaláb P. Chromosomal gain promotes formation of a steep RanGTP gradient that drives mitosis in aneuploid cells. ACTA ACUST UNITED AC 2013; 200:151-61. [PMID: 23319601 PMCID: PMC3549973 DOI: 10.1083/jcb.201206142] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
The chromosome-centered RanGTP gradient, which is strongly reduced in slow-growing normal cells, is amplified by chromosomal gain and is required for mitosis in rapidly growing aneuploid cells. Many mitotic factors were shown to be activated by Ran guanosine triphosphatase. Previous studies in Xenopus laevis egg extracts and in highly proliferative cells showed that mitotic chromosomes were surrounded by steep Ran guanosine triphosphate (GTP) concentration gradients, indicating that RanGTP-activated factors promote spindle assembly around chromosomes. However, the mitotic role of Ran in normal differentiated cells is not known. In this paper, we show that although the steep mitotic RanGTP gradients were present in rapidly growing cell lines and were required for chromosome congression in mitotic HeLa cells, the gradients were strongly reduced in slow-growing primary cells, such as HFF-1 fibroblasts. The overexpression of RCC1, the guanine nucleotide exchange factor for Ran, induced steeper mitotic RanGTP gradients in HFF-1 cells, showing the critical role of RCC1 levels in the regulation of mitosis by Ran. Remarkably, in vitro fusion of HFF-1 cells produced cells with steep mitotic RanGTP gradients comparable to HeLa cells, indicating that chromosomal gain can promote mitosis in aneuploid cancer cells via Ran.
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Affiliation(s)
- Keisuke Hasegawa
- Laboratory of Cellular and Molecular Biology, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA
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Miyazaki K, Wakana Y, Noda C, Arasaki K, Furuno A, Tagaya M. Contribution of the long form of syntaxin 5 to the organization of the endoplasmic reticulum. J Cell Sci 2012; 125:5658-66. [PMID: 23077182 DOI: 10.1242/jcs.105304] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
The SNARE protein syntaxin 5 exists as long (42 kDa) and short (35 kDa) isoforms. The short form is principally localized in the Golgi complex, whereas the long form resides not only in the Golgi but also in the endoplasmic reticulum (ER). Although the Golgi-localized short form has been extensively investigated, little is known about the long form. In the present study, we demonstrate that the long form of syntaxin 5 functions to shape the ER. We found that overexpression of the long form of syntaxin 5 induces rearrangement and co-alignment of the ER membrane with microtubules, the pattern of which is quite similar to that observed in cells overexpressing CLIMP-63, a linker between the ER membrane and microtubules. The ability of syntaxin 5 to induce ER-microtubule rearrangement is not related to its SNARE function, but correlates with its binding affinities for CLIMP-63, and CLIMP-63 is essential for the induction of this rearrangement. Microtubule co-sedimentation assays demonstrated that the long form of syntaxin 5 has a substantial microtubule-binding activity. These results suggest that the long form of syntaxin 5 contributes to the regulation of ER structure by interacting with both CLIMP-63 and microtubules. Indeed, depletion of syntaxin 5 caused the spreading of the ER to the cell periphery, similar to the phenotype observed in cells treated with the microtubule-depolymerizing reagent nocodazole. Our results disclose a previously undescribed function of the long form of syntaxin 5 that is not related to its function as a SNARE.
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Affiliation(s)
- Kaori Miyazaki
- School of Life Sciences, Tokyo University of Pharmacy and Life Sciences, Hachioji, Tokyo 192-0392, Japan
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Tubulin nucleotide status controls Sas-4-dependent pericentriolar material recruitment. Nat Cell Biol 2012; 14:865-73. [PMID: 22729084 PMCID: PMC3411905 DOI: 10.1038/ncb2527] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2011] [Accepted: 05/18/2012] [Indexed: 12/22/2022]
Abstract
Regulated centrosome biogenesis is required for accurate cell division and for maintaining genome integrity1. Centrosomes consist of a centriole pair surrounded by a protein network known as pericentriolar material (PCM)1. PCM assembly is a tightly regulated, critical step that determines a centrosome’s size and capability2–4. Here, we report a role for tubulin in regulating PCM recruitment via the conserved centrosomal protein Sas-4. Tubulin directly binds to Sas-4; together they are components of cytoplasmic complexes of centrosomal proteins5,6. A Sas-4 mutant, which cannot bind tubulin, enhances centrosomal protein complex formation and has abnormally large centrosomes with excessive activity. These suggest that tubulin negatively regulates PCM recruitment. Whereas tubulin-GTP prevents Sas-4 from forming protein complexes, tubulin-GDP promotes it. Thus, tubulin’s regulation of PCM recruitment depends on its GTP/GDP-bound state. These results identify a role for tubulin in regulating PCM recruitment independent of its well-known role as a building block of microtubules7. Based on its guanine bound state, tubulin can act as a molecular switch in PCM recruitment.
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Gable A, Qiu M, Titus J, Balchand S, Ferenz NP, Ma N, Collins ES, Fagerstrom C, Ross JL, Yang G, Wadsworth P. Dynamic reorganization of Eg5 in the mammalian spindle throughout mitosis requires dynein and TPX2. Mol Biol Cell 2012; 23:1254-66. [PMID: 22337772 PMCID: PMC3315814 DOI: 10.1091/mbc.e11-09-0820] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
Kinesin-5 is an essential mitotic motor. However, how its spatial-temporal distribution is regulated in mitosis remains poorly understood. We expressed localization and affinity purification-tagged Eg5 from a mouse bacterial artificial chromosome (this construct was called mEg5) and found its distribution to be tightly regulated throughout mitosis. Fluorescence recovery after photobleaching analysis showed rapid Eg5 turnover throughout mitosis, which cannot be accounted for by microtubule turnover. Total internal reflection fluorescence microscopy and high-resolution, single-particle tracking revealed that mEg5 punctae on both astral and midzone microtubules rapidly bind and unbind. mEg5 punctae on midzone microtubules moved transiently both toward and away from spindle poles. In contrast, mEg5 punctae on astral microtubules moved transiently toward microtubule minus ends during early mitosis but switched to plus end-directed motion during anaphase. These observations explain the poleward accumulation of Eg5 in early mitosis and its redistribution in anaphase. Inhibition of dynein blocked mEg5 movement on astral microtubules, whereas depletion of the Eg5-binding protein TPX2 resulted in plus end-directed mEg5 movement. However, motion of Eg5 on midzone microtubules was not altered. Our results reveal differential and precise spatial and temporal regulation of Eg5 in the spindle mediated by dynein and TPX2.
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Affiliation(s)
- Alyssa Gable
- Department of Biology, University of Massachusetts Amherst, Amherst, MA 01003, USA
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Management of cytoskeleton architecture by molecular chaperones and immunophilins. Cell Signal 2011; 23:1907-20. [PMID: 21864675 DOI: 10.1016/j.cellsig.2011.07.023] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2011] [Revised: 07/22/2011] [Accepted: 07/26/2011] [Indexed: 11/20/2022]
Abstract
Cytoskeletal structure is continually remodeled to accommodate normal cell growth and to respond to pathophysiological cues. As a consequence, several cytoskeleton-interacting proteins become involved in a variety of cellular processes such as cell growth and division, cell movement, vesicle transportation, cellular organelle location and function, localization and distribution of membrane receptors, and cell-cell communication. Molecular chaperones and immunophilins are counted among the most important proteins that interact closely with the cytoskeleton network, in particular with microtubules and microtubule-associated factors. In several situations, heat-shock proteins and immunophilins work together as a functionally active heterocomplex, although both types of proteins also show independent actions. In circumstances where homeostasis is affected by environmental stresses or due to genetic alterations, chaperone proteins help to stabilize the system. Molecular chaperones facilitate the assembly, disassembly and/or folding/refolding of cytoskeletal proteins, so they prevent aberrant protein aggregation. Nonetheless, the roles of heat-shock proteins and immunophilins are not only limited to solve abnormal situations, but they also have an active participation during the normal differentiation process of the cell and are key factors for many structural and functional rearrangements during this course of action. Cytoskeleton modifications leading to altered localization of nuclear factors may result in loss- or gain-of-function of such factors, which affects the cell cycle and cell development. Therefore, cytoskeletal components are attractive therapeutic targets, particularly microtubules, to prevent pathological situations such as rapidly dividing tumor cells or to favor the process of cell differentiation in other cases. In this review we will address some classical and novel aspects of key regulatory functions of heat-shock proteins and immunophilins as housekeeping factors of the cytoskeletal network.
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Wühr M, Obholzer N, Megason S, Detrich H, Mitchison T. Live imaging of the cytoskeleton in early cleavage-stage zebrafish embryos. Methods Cell Biol 2011; 101:1-18. [PMID: 21550437 PMCID: PMC6551615 DOI: 10.1016/b978-0-12-387036-0.00001-3] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
The large and transparent cells of cleavage-stage zebrafish embryos provide unique opportunities to study cell division and cytoskeletal dynamics in very large animal cells. Here, we summarize recent progress, from our laboratories and others, on live imaging of the microtubule and actin cytoskeletons during zebrafish embryonic cleavage. First, we present simple protocols for extending the breeding competence of zebrafish mating ensembles throughout the day, which ensures a steady supply of embryos in early cleavage, and for mounting these embryos for imaging. Second, we describe a transgenic zebrafish line [Tg(bactin2:HsENSCONSIN17-282-3xEGFP)hm1] that expresses the green fluorescent protein (GFP)-labeled microtubule-binding part of ensconsin (EMTB-3GFP). We demonstrate that the microtubule-based structures of the early cell cycles can be imaged live, with single microtubule resolution and with high contrast, in this line. Microtubules are much more easily visualized using this tagged binding protein rather than directly labeled tubulin (injected Alexa-647-labeled tubulin), presumably due to lower background from probe molecules not attached to microtubules. Third, we illustrate live imaging of the actin cytoskeleton by injection of the actin-binding fragment of utrophin fused to GFP. Fourth, we compare epifluorescence-, spinning-disc-, laser-scanning-, and two-photon-microscopic modalities for live imaging of the microtubule cytoskeleton in early embryos of our EMTB-3GFP-expressing transgenic line. Finally, we discuss future applications and extensions of our methods.
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Affiliation(s)
- M. Wühr
- Department of Systems Biology, Harvard Medical School, Boston, Massachusetts 02115, USA
| | - N.D. Obholzer
- Department of Systems Biology, Harvard Medical School, Boston, Massachusetts 02115, USA
| | - S.G. Megason
- Department of Systems Biology, Harvard Medical School, Boston, Massachusetts 02115, USA
| | - H.W. Detrich
- Department of Biology, Northeastern University, Boston, Massachusetts 02115, USA
| | - T.J. Mitchison
- Department of Systems Biology, Harvard Medical School, Boston, Massachusetts 02115, USA
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Wei JH, Seemann J. Nakiterpiosin targets tubulin and triggers mitotic catastrophe in human cancer cells. Mol Cancer Ther 2010; 9:3375-85. [PMID: 21139045 DOI: 10.1158/1535-7163.mct-10-0305] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Agents that interfere with mitotic progression by perturbing microtubule dynamics are commonly used for cancer chemotherapy. Here, we identify nakiterpiosin as a novel antimitotic drug that targets microtubules. Nakiterpiosin induces mitotic arrest and triggers mitotic catastrophe in human cancer cells by impairing bipolar spindle assembly. At higher concentration, it alters the interphase microtubule network and suppresses microtubule dynamics. In the presence of nakiterpiosin, microtubules are no longer arranged in a centrosomal array and centrosome-mediated microtubule regrowth after cold depolymerization is inhibited. However, centrosome organization, the ultrastructure of Golgi stacks, and protein secretion are not affected, suggesting that the drug has minimal toxicity toward other cellular functions. Nakiterpiosin interacts directly with tubulin, inhibits microtubule polymerization in vitro, and decreases polymer mass in cells. Furthermore, it enhances tubulin acetylation and reduces viability of paclitaxel-resistant cancer cells. In conclusion, nakiterpiosin exerts antiproliferative activity by perturbing microtubule dynamics during mitosis that activates the spindle assembly checkpoint and triggers cell death. These findings suggest the potential use of nakiterpiosin as a chemotherapeutic agent.
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Affiliation(s)
- Jen-Hsuan Wei
- Department of Cell Biology, University of Texas Southwestern Medical Center, Dallas, Texas 75390, USA
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Hage-Sleiman R, Herveau S, Matera EL, Laurier JF, Dumontet C. Tubulin binding cofactor C (TBCC) suppresses tumor growth and enhances chemosensitivity in human breast cancer cells. BMC Cancer 2010; 10:135. [PMID: 20384997 PMCID: PMC2859754 DOI: 10.1186/1471-2407-10-135] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2009] [Accepted: 04/12/2010] [Indexed: 12/22/2022] Open
Abstract
Background Microtubules are considered major therapeutic targets in patients with breast cancer. In spite of their essential role in biological functions including cell motility, cell division and intracellular transport, microtubules have not yet been considered as critical actors influencing tumor cell aggressivity. To evaluate the impact of microtubule mass and dynamics on the phenotype and sensitivity of breast cancer cells, we have targeted tubulin binding cofactor C (TBCC), a crucial protein for the proper folding of α and β tubulins into polymerization-competent tubulin heterodimers. Methods We developed variants of human breast cancer cells with increased content of TBCC. Analysis of proliferation, cell cycle distribution and mitotic durations were assayed to investigate the influence of TBCC on the cell phenotype. In vivo growth of tumors was monitored in mice xenografted with breast cancer cells. The microtubule dynamics and the different fractions of tubulins were studied by time-lapse microscopy and lysate fractionation, respectively. In vitro sensitivity to antimicrotubule agents was studied by flow cytometry. In vivo chemosensitivity was assayed by treatment of mice implanted with tumor cells. Results TBCC overexpression influenced tubulin fraction distribution, with higher content of nonpolymerizable tubulins and lower content of polymerizable dimers and microtubules. Microtubule dynamicity was reduced in cells overexpressing TBCC. Cell cycle distribution was altered in cells containing larger amounts of TBCC with higher percentage of cells in G2-M phase and lower percentage in S-phase, along with slower passage into mitosis. While increased content of TBCC had little effect on cell proliferation in vitro, we observed a significant delay in tumor growth with respect to controls when TBCC overexpressing cells were implanted as xenografts in vivo. TBCC overexpressing variants displayed enhanced sensitivity to antimicrotubule agents both in vitro and in xenografts. Conclusion These results underline the essential role of fine tuned regulation of tubulin content in tumor cells and the major impact of dysregulation of tubulin dimer content on tumor cell phenotype and response to chemotherapy. A better understanding of how the microtubule cytoskeleton is dysregulated in cancer cells would greatly contribute to a better understanding of tumor cell biology and characterisation of resistant phenotypes.
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Affiliation(s)
- Rouba Hage-Sleiman
- Inserm U590, Laboratoire de Cytologie Analytique, Université Lyon 1, 69008 Lyon, France.
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