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Lima JT, Ferreira JG. Mechanobiology of the nucleus during the G2-M transition. Nucleus 2024; 15:2330947. [PMID: 38533923 DOI: 10.1080/19491034.2024.2330947] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2023] [Accepted: 03/09/2024] [Indexed: 03/28/2024] Open
Abstract
Cellular behavior is continuously influenced by mechanical forces. These forces span the cytoskeleton and reach the nucleus, where they trigger mechanotransduction pathways that regulate downstream biochemical events. Therefore, the nucleus has emerged as a regulator of cellular response to mechanical stimuli. Cell cycle progression is regulated by cyclin-CDK complexes. Recent studies demonstrated these biochemical pathways are influenced by mechanical signals, highlighting the interdependence of cellular mechanics and cell cycle regulation. In particular, the transition from G2 to mitosis (G2-M) shows significant changes in nuclear structure and organization, ranging from nuclear pore complex (NPC) and nuclear lamina disassembly to chromosome condensation. The remodeling of these mechanically active nuclear components indicates that mitotic entry is particularly sensitive to forces. Here, we address how mechanical forces crosstalk with the nucleus to determine the timing and efficiency of the G2-M transition. Finally, we discuss how the deregulation of nuclear mechanics has consequences for mitosis.
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Affiliation(s)
- Joana T Lima
- Epithelial Polarity and Cell Division Laboratory, Instituto de Investigação e Inovação em Saúde (i3S), Porto, Portugal
- Departamento de Biomedicina, Unidade de Biologia Experimental, Faculdade de Medicina do Porto, Porto, Portugal
- Programa Doutoral em Biomedicina, Faculdade de Medicina, Universidade do Porto, Porto, Portugal
| | - Jorge G Ferreira
- Epithelial Polarity and Cell Division Laboratory, Instituto de Investigação e Inovação em Saúde (i3S), Porto, Portugal
- Departamento de Biomedicina, Unidade de Biologia Experimental, Faculdade de Medicina do Porto, Porto, Portugal
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2
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Aquino-Perez C, Safaralizade M, Podhajecky R, Wang H, Lansky Z, Grosse R, Macurek L. FAM110A promotes mitotic spindle formation by linking microtubules with actin cytoskeleton. Proc Natl Acad Sci U S A 2024; 121:e2321647121. [PMID: 38995965 PMCID: PMC11260166 DOI: 10.1073/pnas.2321647121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2024] [Accepted: 06/06/2024] [Indexed: 07/14/2024] Open
Abstract
Precise segregation of chromosomes during mitosis requires assembly of a bipolar mitotic spindle followed by correct attachment of microtubules to the kinetochores. This highly spatiotemporally organized process is controlled by various mitotic kinases and molecular motors. We have recently shown that Casein Kinase 1 (CK1) promotes timely progression through mitosis by phosphorylating FAM110A leading to its enrichment at spindle poles. However, the mechanism by which FAM110A exerts its function in mitosis is unknown. Using structure prediction and a set of deletion mutants, we mapped here the interaction of the N- and C-terminal domains of FAM110A with actin and tubulin, respectively. Next, we found that the FAM110A-Δ40-61 mutant deficient in actin binding failed to rescue defects in chromosomal alignment caused by depletion of endogenous FAM110A. Depletion of FAM110A impaired assembly of F-actin in the proximity of spindle poles and was rescued by expression of the wild-type FAM110A, but not the FAM110A-Δ40-61 mutant. Purified FAM110A promoted binding of F-actin to microtubules as well as bundling of actin filaments in vitro. Finally, we found that the inhibition of CK1 impaired spindle actin formation and delayed progression through mitosis. We propose that CK1 and FAM110A promote timely progression through mitosis by mediating the interaction between spindle microtubules and filamentous actin to ensure proper mitotic spindle formation.
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Affiliation(s)
- Cecilia Aquino-Perez
- Cancer Cell Biology, Institute of Molecular Genetics, Czech Academy of Sciences, PragueCZ14220, Czech Republic
| | - Mahira Safaralizade
- Institute for Clinical and Experimental Pharmacology and Toxicology I, Medical Faculty, University of Freiburg, Freiburg79104, Germany
| | - Roman Podhajecky
- Institute of Biotechnology, Czech Academy of Sciences, Biocev, VestecCZ25250, Czech Republic
| | - Hong Wang
- Institute for Clinical and Experimental Pharmacology and Toxicology I, Medical Faculty, University of Freiburg, Freiburg79104, Germany
- Centre for Integrative Biological Signaling Studies, University of Freiburg, Freiburg79104, Germany
| | - Zdenek Lansky
- Institute of Biotechnology, Czech Academy of Sciences, Biocev, VestecCZ25250, Czech Republic
| | - Robert Grosse
- Institute for Clinical and Experimental Pharmacology and Toxicology I, Medical Faculty, University of Freiburg, Freiburg79104, Germany
- Centre for Integrative Biological Signaling Studies, University of Freiburg, Freiburg79104, Germany
| | - Libor Macurek
- Cancer Cell Biology, Institute of Molecular Genetics, Czech Academy of Sciences, PragueCZ14220, Czech Republic
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3
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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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4
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Hannaford MR, Rusan NM. Positioning centrioles and centrosomes. J Cell Biol 2024; 223:e202311140. [PMID: 38512059 PMCID: PMC10959756 DOI: 10.1083/jcb.202311140] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2023] [Revised: 02/23/2024] [Accepted: 02/26/2024] [Indexed: 03/22/2024] Open
Abstract
Centrosomes are the primary microtubule organizer in eukaryotic cells. In addition to shaping the intracellular microtubule network and the mitotic spindle, centrosomes are responsible for positioning cilia and flagella. To fulfill these diverse functions, centrosomes must be properly located within cells, which requires that they undergo intracellular transport. Importantly, centrosome mispositioning has been linked to ciliopathies, cancer, and infertility. The mechanisms by which centrosomes migrate are diverse and context dependent. In many cells, centrosomes move via indirect motor transport, whereby centrosomal microtubules engage anchored motor proteins that exert forces on those microtubules, resulting in centrosome movement. However, in some cases, centrosomes move via direct motor transport, whereby the centrosome or centriole functions as cargo that directly binds molecular motors which then walk on stationary microtubules. In this review, we summarize the mechanisms of centrosome motility and the consequences of centrosome mispositioning and identify key questions that remain to be addressed.
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Affiliation(s)
- Matthew R. Hannaford
- Cell and Developmental Biology Center, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD, USA
| | - Nasser M. Rusan
- Cell and Developmental Biology Center, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD, USA
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5
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Zhang F, Wu L, Feng S, Zhao Z, Zhang K, Thakur A, Xu Z, Liang Q, Liu Y, Liu W, Yan Y. FHOD1 is upregulated in glioma cells and attenuates ferroptosis of glioma cells by targeting HSPB1 signaling. CNS Neurosci Ther 2023; 29:3351-3363. [PMID: 37211949 PMCID: PMC10580363 DOI: 10.1111/cns.14264] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2023] [Revised: 04/09/2023] [Accepted: 04/11/2023] [Indexed: 05/23/2023] Open
Abstract
BACKGROUND As a new type of regulatory cell death, ferroptosis has been proven to be involved in cancer pathogenesis and therapeutic response. However, the detailed roles of ferroptosis or ferroptosis-associated genes in glioma remain to be clarified. METHODS Here, we performed the TMT/iTRAQ-Based Quantitative Proteomic Approach to identify the differentially expressed proteins between glioma specimens and adjacent tissues. Kaplan-Meier survival was used to estimate the survival values. We also explored the regulatory roles of abnormally expressed formin homology 2 domain-containing protein 1 (FHOD1) in glioma ferroptosis sensitivity. RESULTS In our study, FHOD1 was identified to be the most significantly upregulated protein in glioma tissues. Multiple glioma datasets revealed that the glioma patients with low FHOD1 expression displayed favorable survival time. Functional analysis proved that the knockdown of FHOD1 inhibited cell growth and improved the cellular sensitivity to ferroptosis in glioma cells T98G and U251. Mechanically, we found the up-regulation and hypomethylation of HSPB1, a negative regulator of ferroptosis, in glioma tissues. FHOD1 knockdown could enhance the ferroptosis sensitivity of glioma cells via up-regulating the methylated heat-shock protein B (HSPB1). Overexpression of HSPB1 significantly reversed FHOD1 knockdown-mediated ferroptosis. CONCLUSIONS In summary, this study demonstrated that the FHOD1-HSPB1 axis exerts marked regulatory effects on ferroptosis, and might affect the prognosis and therapeutic response in glioma.
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Affiliation(s)
- Fan Zhang
- Department of Gynecology, Xiangya HospitalCentral South UniversityChangshaChina
- Department of Physiology, School of Basic Medical ScienceCentral South UniversityChangshaChina
| | - Lixiang Wu
- Department of Physiology, School of Basic Medical ScienceCentral South UniversityChangshaChina
| | - Songshan Feng
- Department of Neurosurgery, Xiangya HospitalCentral South UniversityChangshaChina
| | - Zijin Zhao
- Department of Neurosurgery, Xiangya HospitalCentral South UniversityChangshaChina
| | - Kui Zhang
- State Key Laboratory of Silkworm Genome Biology, Medical Research InstituteSouthwest UniversityChongqingChina
| | - Abhimanyu Thakur
- Pritzker School of Molecular Engineering, Ben May Department for Cancer ResearchUniversity of ChicagoChicagoIllinoisUSA
| | - Zhijie Xu
- Department of Pathology, Xiangya HospitalCentral South UniversityChangshaChina
| | - Qiuju Liang
- Department of Pharmacy, Xiangya HospitalCentral South UniversityChangshaChina
| | - Yuanhong Liu
- Department of Pharmacy, Xiangya HospitalCentral South UniversityChangshaChina
| | - Wei Liu
- Department of Pathology, Xiangya HospitalCentral South UniversityChangshaChina
| | - Yuanliang Yan
- Department of Pharmacy, Xiangya HospitalCentral South UniversityChangshaChina
- National Clinical Research Center for Geriatric Disorders, Xiangya HospitalCentral South UniversityChangshaChina
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6
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Monteiro P, Yeon B, Wallis SS, Godinho SA. Centrosome amplification fine tunes tubulin acetylation to differentially control intracellular organization. EMBO J 2023; 42:e112812. [PMID: 37403793 PMCID: PMC10425843 DOI: 10.15252/embj.2022112812] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2022] [Revised: 06/05/2023] [Accepted: 06/14/2023] [Indexed: 07/06/2023] Open
Abstract
Intracellular organelle organization is conserved in eukaryotic cells and is primarily achieved through active transport by motor proteins along the microtubule cytoskeleton. Microtubule post-translational modifications (PTMs) can contribute to microtubule diversity and differentially regulate motor-mediated transport. Here, we show that centrosome amplification, commonly observed in cancer and shown to promote aneuploidy and invasion, induces a global change in organelle positioning towards the cell periphery and facilitates nuclear migration through confined spaces. This reorganization requires kinesin-1 and is analogous to the loss of dynein. Cells with amplified centrosomes display increased levels of acetylated tubulin, a PTM that could enhance kinesin-1-mediated transport. Depletion of α-tubulin acetyltransferase 1 (αTAT1) to block tubulin acetylation rescues the displacement of centrosomes, mitochondria, and vimentin but not Golgi or endosomes. Analyses of the distribution of total and acetylated microtubules indicate that the polarized distribution of modified microtubules, rather than levels alone, plays an important role in the positioning of specific organelles, such as the centrosome. We propose that increased tubulin acetylation differentially impacts kinesin-1-mediated organelle displacement to regulate intracellular organization.
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Affiliation(s)
- Pedro Monteiro
- Centre for Cancer Cell and Molecular Biology, Barts Cancer InstituteQueen Mary University of LondonLondonUK
- Institut Curie, Paris Sciences and Lettres Research UniversityCentre National de la Recherche Scientifique, UMR144ParisFrance
| | - Bongwhan Yeon
- Centre for Cancer Cell and Molecular Biology, Barts Cancer InstituteQueen Mary University of LondonLondonUK
| | - Samuel S Wallis
- Centre for Cancer Cell and Molecular Biology, Barts Cancer InstituteQueen Mary University of LondonLondonUK
| | - Susana A Godinho
- Centre for Cancer Cell and Molecular Biology, Barts Cancer InstituteQueen Mary University of LondonLondonUK
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7
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Dang D, Efstathiou C, Sun D, Yue H, Sastry NR, Draviam VM. Deep learning techniques and mathematical modeling allow 3D analysis of mitotic spindle dynamics. J Cell Biol 2023; 222:213913. [PMID: 36880744 PMCID: PMC9998659 DOI: 10.1083/jcb.202111094] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2021] [Revised: 12/03/2022] [Accepted: 01/31/2023] [Indexed: 03/08/2023] Open
Abstract
Time-lapse microscopy movies have transformed the study of subcellular dynamics. However, manual analysis of movies can introduce bias and variability, obscuring important insights. While automation can overcome such limitations, spatial and temporal discontinuities in time-lapse movies render methods such as 3D object segmentation and tracking difficult. Here, we present SpinX, a framework for reconstructing gaps between successive image frames by combining deep learning and mathematical object modeling. By incorporating expert feedback through selective annotations, SpinX identifies subcellular structures, despite confounding neighbor-cell information, non-uniform illumination, and variable fluorophore marker intensities. The automation and continuity introduced here allows the precise 3D tracking and analysis of spindle movements with respect to the cell cortex for the first time. We demonstrate the utility of SpinX using distinct spindle markers, cell lines, microscopes, and drug treatments. In summary, SpinX provides an exciting opportunity to study spindle dynamics in a sophisticated way, creating a framework for step changes in studies using time-lapse microscopy.
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Affiliation(s)
- David Dang
- School of Biological and Behavioural Sciences, Queen Mary University of London , London, UK.,Department of Informatics, King's College London , London, UK
| | | | - Dijue Sun
- School of Biological and Behavioural Sciences, Queen Mary University of London , London, UK
| | - Haoran Yue
- School of Biological and Behavioural Sciences, Queen Mary University of London , London, UK
| | | | - Viji M Draviam
- School of Biological and Behavioural Sciences, Queen Mary University of London , London, UK
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8
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Gallisà-Suñé N, Sànchez-Fernàndez-de-Landa P, Zimmermann F, Serna M, Regué L, Paz J, Llorca O, Lüders J, Roig J. BICD2 phosphorylation regulates dynein function and centrosome separation in G2 and M. Nat Commun 2023; 14:2434. [PMID: 37105961 PMCID: PMC10140047 DOI: 10.1038/s41467-023-38116-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2021] [Accepted: 04/17/2023] [Indexed: 04/29/2023] Open
Abstract
The activity of dynein is regulated by a number of adaptors that mediate its interaction with dynactin, effectively activating the motor complex while also connecting it to different cargos. The regulation of adaptors is consequently central to dynein physiology but remains largely unexplored. We now describe that one of the best-known dynein adaptors, BICD2, is effectively activated through phosphorylation. In G2, phosphorylation of BICD2 by CDK1 promotes its interaction with PLK1. In turn, PLK1 phosphorylation of a single residue in the N-terminus of BICD2 results in a structural change that facilitates the interaction with dynein and dynactin, allowing the formation of active motor complexes. Moreover, modified BICD2 preferentially interacts with the nucleoporin RanBP2 once RanBP2 has been phosphorylated by CDK1. BICD2 phosphorylation is central for dynein recruitment to the nuclear envelope, centrosome tethering to the nucleus and centrosome separation in the G2 and M phases of the cell cycle. This work reveals adaptor activation through phosphorylation as crucial for the spatiotemporal regulation of dynein activity.
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Affiliation(s)
- Núria Gallisà-Suñé
- Department of Cells and Tissues, Molecular Biology Institute of Barcelona (IBMB-CSIC), Baldiri i Reixac 10-12, 08028, Barcelona, Spain
| | - Paula Sànchez-Fernàndez-de-Landa
- Department of Cells and Tissues, Molecular Biology Institute of Barcelona (IBMB-CSIC), Baldiri i Reixac 10-12, 08028, Barcelona, Spain
- Aging and Metabolism Programme, IRB Barcelona, Barcelona, Spain
| | - Fabian Zimmermann
- Mechanisms of Disease Programme, Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology, Baldiri Reixac 10-12, 08028, Barcelona, Spain
| | - Marina Serna
- Structural Biology Programme, Spanish National Cancer Research Centre (CNIO), Melchor Fernández Almagro 3, E-28029, Madrid, Spain
| | - Laura Regué
- Department of Cells and Tissues, Molecular Biology Institute of Barcelona (IBMB-CSIC), Baldiri i Reixac 10-12, 08028, Barcelona, Spain
| | - Joel Paz
- Mechanisms of Disease Programme, Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology, Baldiri Reixac 10-12, 08028, Barcelona, Spain
| | - Oscar Llorca
- Structural Biology Programme, Spanish National Cancer Research Centre (CNIO), Melchor Fernández Almagro 3, E-28029, Madrid, Spain
| | - Jens Lüders
- Mechanisms of Disease Programme, Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology, Baldiri Reixac 10-12, 08028, Barcelona, Spain
| | - Joan Roig
- Department of Cells and Tissues, Molecular Biology Institute of Barcelona (IBMB-CSIC), Baldiri i Reixac 10-12, 08028, Barcelona, Spain.
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9
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Zhao Y, Yang J, Lu D, Zhu Y, Liao K, Tian Y, Yin R. The Loss-Function of KNL1 Causes Oligospermia and Asthenospermia in Mice by Affecting the Assembly and Separation of the Spindle through Flow Cytometry and Immunofluorescence. SENSORS (BASEL, SWITZERLAND) 2023; 23:2571. [PMID: 36904774 PMCID: PMC10007211 DOI: 10.3390/s23052571] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/15/2023] [Revised: 02/13/2023] [Accepted: 02/20/2023] [Indexed: 06/18/2023]
Abstract
KNL1 (kinetochore scaffold 1) has attracted much attention as one of the assembly elements of the outer kinetochore, and the functions of its different domains have been gradually revealed, most of which are associated with cancers, but few links have been made between KNL1 and male fertility. Here, we first linked KNL1 to male reproductive health and the loss-function of KNL1 resulted in oligospermia and asthenospermia in mice (an 86.5% decrease in total sperm number and an 82.4% increase in static sperm number, respectively) through CASA (computer-aided sperm analysis). Moreover, we introduced an ingenious method to pinpoint the abnormal stage in the spermatogenic cycle using flow cytometry combined with immunofluorescence. Results showed that 49.5% haploid sperm was reduced and 53.2% diploid sperm was increased after the function of KNL1 was lost. Spermatocytes arrest was identified at the meiotic prophase I of spermatogenesis, which was induced by the abnormal assembly and separation of the spindle. In conclusion, we established an association between KNL1 and male fertility, providing a guide for future genetic counseling regarding oligospermia and asthenospermia, and a powerful method for further exploring spermatogenic dysfunction by utilizing flow cytometry and immunofluorescence.
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Affiliation(s)
- Yuwei Zhao
- State Key Laboratory of Genetic Engineering, School of Life Sciences, Fudan University, Shanghai 200000, China
| | - Jingmin Yang
- State Key Laboratory of Genetic Engineering, School of Life Sciences, Fudan University, Shanghai 200000, China
- Shanghai WeHealth BioMedical Technology Co., Ltd., Shanghai 201318, China
- NHC Key Laboratory of Birth Defects and Reproductive Health, Chongqing Population and Family Planning Science and Technology Research Institute, Chongqing 404100, China
| | - Daru Lu
- State Key Laboratory of Genetic Engineering, School of Life Sciences, Fudan University, Shanghai 200000, China
- NHC Key Laboratory of Birth Defects and Reproductive Health, Chongqing Population and Family Planning Science and Technology Research Institute, Chongqing 404100, China
| | - Yijian Zhu
- NHC Key Laboratory of Birth Defects and Reproductive Health, Chongqing Population and Family Planning Science and Technology Research Institute, Chongqing 404100, China
| | - Kai Liao
- State Key Laboratory of Genetic Engineering, School of Life Sciences, Fudan University, Shanghai 200000, China
| | - Yafei Tian
- State Key Laboratory of Genetic Engineering, School of Life Sciences, Fudan University, Shanghai 200000, China
- Shanghai WeHealth BioMedical Technology Co., Ltd., Shanghai 201318, China
| | - Rui Yin
- NHC Key Laboratory of Birth Defects and Reproductive Health, Chongqing Population and Family Planning Science and Technology Research Institute, Chongqing 404100, China
- Reproductive Medicine Research Center, Medical Research Institute, Southwest University, Chongqing 400715, China
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10
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Song C, Zhang Y, Li Y, Bie J, Wang Z, Yang X, Li H, Zhu L, Zhang T, Chang Q, Luo J. The phosphorylation of PHF5A by TrkA-ERK1/2-ABL1 cascade regulates centrosome separation. Cell Death Dis 2023; 14:98. [PMID: 36759599 PMCID: PMC9911754 DOI: 10.1038/s41419-023-05561-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2022] [Revised: 12/22/2022] [Accepted: 01/05/2023] [Indexed: 02/11/2023]
Abstract
During interphase, the newly duplicated pairs of centrosomes are held together by a centrosome linker, and the centrosome separation needs the disruption of this linker to induce the duplicated centrosomes separating into two distinct microtubule organization centers. The mechanism of regulating centrosome separation is however poorly understood. Here, we demonstrated that the phosphorylation of PHF5A at Y36 by the TrkA-ERK1/2-ABL1 cascade plays a critical role in regulating centrosome separation. PHF5A, a well-characterized spliceosome component, is enriched in the centrosome. The pY36-PHF5A promotes the interaction between CEP250 and Nek2A in a spliceosomal-independent manner, which leads to premature centrosome separation. Furthermore, the unmatured centrosome remodels the microtubule and subsequently regulates cell proliferation and migration. Importantly, we found that the phosphorylation cascade of TrkA-ERK1/2-ABL1-PHF5A is hyper-regulated in medulloblastoma. The inhibition of this cascade can induce senescence and restrict the proliferation of medulloblastoma. Our findings on this phosphorylation cascade in regulating centrosome separation could provide a series of potential targets for restricting the progress of medulloblastoma.
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Affiliation(s)
- Chen Song
- Department of Medical Genetics, Center for Medical Genetics, Peking University Health Science Center, Beijing, 100191, China
| | - Yu Zhang
- Department of Medical Genetics, Center for Medical Genetics, Peking University Health Science Center, Beijing, 100191, China
| | - Yutong Li
- Department of Medical Genetics, Center for Medical Genetics, Peking University Health Science Center, Beijing, 100191, China
| | - Juntao Bie
- Department of Medical Genetics, Center for Medical Genetics, Peking University Health Science Center, Beijing, 100191, China
| | - Zhe Wang
- Department of Medical Genetics, Center for Medical Genetics, Peking University Health Science Center, Beijing, 100191, China
- Institute for Cancer Genetics, Columbia University, New York, NY, 10032, USA
| | - Xin Yang
- Department of Medical Genetics, Center for Medical Genetics, Peking University Health Science Center, Beijing, 100191, China
- Institute for Cancer Genetics, Columbia University, New York, NY, 10032, USA
| | - Haishuang Li
- Department of Pathology, Peking University School of Basic Medical Science; Peking University Third Hospital, Peking University Health Science Center, Beijing, 100191, China
| | - Liangyi Zhu
- Department of Pathology, Peking University School of Basic Medical Science; Peking University Third Hospital, Peking University Health Science Center, Beijing, 100191, China
| | - Tianzhuo Zhang
- Department of Medical Genetics, Center for Medical Genetics, Peking University Health Science Center, Beijing, 100191, China
| | - Qing Chang
- Department of Pathology, Peking University School of Basic Medical Science; Peking University Third Hospital, Peking University Health Science Center, Beijing, 100191, China.
| | - Jianyuan Luo
- Department of Medical Genetics, Center for Medical Genetics, Peking University Health Science Center, Beijing, 100191, China.
- Department of Biochemistry and Biophysics, Beijing Key Laboratory of Protein Posttranslational Modifications and Cell Function, Center for Medical Genetics, Peking University Health Science Center, Beijing, 100191, China.
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11
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Dantas M, Oliveira A, Aguiar P, Maiato H, Ferreira JG. Nuclear tension controls mitotic entry by regulating cyclin B1 nuclear translocation. J Cell Biol 2022; 221:213539. [PMID: 36222828 PMCID: PMC9565158 DOI: 10.1083/jcb.202205051] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2022] [Revised: 07/15/2022] [Accepted: 09/14/2022] [Indexed: 12/13/2022] Open
Abstract
As cells prepare to divide, they must ensure that enough space is available to assemble the mitotic machinery without perturbing tissue homeostasis. To do so, cells undergo a series of biochemical reactions regulated by cyclin B1-CDK1 that trigger cytoskeletal reorganization and ensure the coordination of cytoplasmic and nuclear events. Along with the biochemical events that control mitotic entry, mechanical forces have recently emerged as important players in cell-cycle regulation. However, the exact link between mechanical forces and the biochemical pathways that control mitotic progression remains unknown. Here, we identify a tension-dependent signal on the nucleus that sets the time for nuclear envelope permeabilization (NEP) and mitotic entry. This signal relies on actomyosin contractility, which unfolds the nucleus during the G2-M transition, activating the stretch-sensitive cPLA2 on the nuclear envelope and regulating the nuclear translocation of cyclin B1. Our data demonstrate how nuclear tension during the G2-M transition contributes to timely and efficient mitotic spindle assembly and prevents chromosomal instability.
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Affiliation(s)
- Margarida Dantas
- Instituto de Investigação e Inovação em Saúde (i3S), Universidade do Porto, Porto, Portugal,BiotechHealth PhD program, Instituto de Ciências Biomédicas Abel Salazar (ICBAS), Porto, Portugal
| | - Andreia Oliveira
- Instituto de Investigação e Inovação em Saúde (i3S), Universidade do Porto, Porto, Portugal
| | - Paulo Aguiar
- Instituto de Investigação e Inovação em Saúde (i3S), Universidade do Porto, Porto, Portugal
| | - Helder Maiato
- Instituto de Investigação e Inovação em Saúde (i3S), Universidade do Porto, Porto, Portugal,Departamento de Biomedicina, Faculdade de Medicina do Porto, Porto, Portugal,Instituto de Biologia Molecular e Celular (IBMC), Universidade do Porto, Porto, Portugal
| | - Jorge G. Ferreira
- Instituto de Investigação e Inovação em Saúde (i3S), Universidade do Porto, Porto, Portugal,Departamento de Biomedicina, Faculdade de Medicina do Porto, Porto, Portugal,Instituto de Biologia Molecular e Celular (IBMC), Universidade do Porto, Porto, Portugal,Correspondence to Jorge G. Ferreira:
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12
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Abstract
The centrosome, consisting of centrioles and the associated pericentriolar material, is the main microtubule-organizing centre (MTOC) in animal cells. During most of interphase, the two centrosomes of a cell are joined together by centrosome cohesion into one MTOC. The most dominant element of centrosome cohesion is the centrosome linker, an interdigitating, fibrous network formed by the protein C-Nap1 anchoring a number of coiled-coil proteins including rootletin to the proximal end of centrioles. Alternatively, centrosomes can be kept together by the action of the minus end directed kinesin motor protein KIFC3 that works on interdigitating microtubules organized by both centrosomes and probably by the actin network. Although cells connect the two interphase centrosomes by several mechanisms into one MTOC, the general importance of centrosome cohesion, particularly for an organism, is still largely unclear. In this article, we review the functions of the centrosome linker and discuss how centrosome cohesion defects can lead to diseases.
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Affiliation(s)
- Hairuo Dang
- Zentrum für Molekulare Biologie der Universität Heidelberg, Deutsches Krebsforschungszentrum-ZMBH Allianz, and,Heidelberg Biosciences International Graduate School (HBIGS), Universität Heidelberg, Heidelberg 69120, Germany
| | - Elmar Schiebel
- Zentrum für Molekulare Biologie der Universität Heidelberg, Deutsches Krebsforschungszentrum-ZMBH Allianz, and
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13
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She ZY, Zhong N, Wei YL. Kinesin-5 Eg5 mediates centrosome separation to control spindle assembly in spermatocytes. Chromosoma 2022; 131:87-105. [PMID: 35437661 DOI: 10.1007/s00412-022-00772-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2021] [Revised: 03/12/2022] [Accepted: 04/08/2022] [Indexed: 11/25/2022]
Abstract
Timely and accurate centrosome separation is critical for bipolar spindle organization and faithful chromosome segregation during cell division. Kinesin-5 Eg5 is essential for centrosome separation and spindle organization in somatic cells; however, the detailed functions and mechanisms of Eg5 in spermatocytes remain unclear. In this study, we show that Eg5 proteins are located at spindle microtubules and centrosomes in spermatocytes both in vivo and in vitro. We reveal that the spermatocytes are arrested at metaphase I in seminiferous tubules after Eg5 inhibition. Eg5 ablation results in cell cycle arrest, the formation of monopolar spindle, and chromosome misalignment in cultured GC-2 spd cells. Importantly, we find that the long-term inhibition of Eg5 results in an increased number of centrosomes and chromosomal instability in spermatocytes. Our findings indicate that Eg5 mediates centrosome separation to control spindle assembly and chromosome alignment in spermatocytes, which finally contribute to chromosome stability and faithful cell division of the spermatocytes.
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Affiliation(s)
- Zhen-Yu She
- Department of Cell Biology and Genetics, The School of Basic Medical Sciences, Fujian Medical University, Fuzhou, 350122, Fujian, China.
- Key Laboratory of Stem Cell Engineering and Regenerative Medicine, Fujian Province University, Fuzhou, 350122, Fujian, China.
| | - Ning Zhong
- Department of Cell Biology and Genetics, The School of Basic Medical Sciences, Fujian Medical University, Fuzhou, 350122, Fujian, China
- Key Laboratory of Stem Cell Engineering and Regenerative Medicine, Fujian Province University, Fuzhou, 350122, Fujian, China
| | - Ya-Lan Wei
- Fujian Obstetrics and Gynecology Hospital, Fuzhou, 350011, Fujian, China
- Medical Research Center, Fujian Maternity and Child Health Hospital, Affiliated Hospital of Fujian Medical University, Fuzhou, 350001, Fujian, China
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14
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von der Heyde EL, Hallmann A. Molecular and cellular dynamics of early embryonic cell divisions in Volvox carteri. THE PLANT CELL 2022; 34:1326-1353. [PMID: 35018470 PMCID: PMC9026201 DOI: 10.1093/plcell/koac004] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/17/2021] [Accepted: 01/03/2022] [Indexed: 06/14/2023]
Abstract
Cell division is fundamental to all organisms and the green alga used here exhibits both key animal and plant functions. Specifically, we analyzed the molecular and cellular dynamics of early embryonic divisions of the multicellular green alga Volvox carteri (Chlamydomonadales). Relevant proteins related to mitosis and cytokinesis were identified in silico, the corresponding genes were cloned, fused to yfp, and stably expressed in Volvox, and the tagged proteins were studied by live-cell imaging. We reveal rearrangements of the microtubule cytoskeleton during centrosome separation, spindle formation, establishment of the phycoplast, and generation of previously unknown structures. The centrosomes participate in initiation of spindle formation and determination of spindle orientation. Although the nuclear envelope does not break down during early mitosis, intermixing of cytoplasm and nucleoplasm results in loss of nuclear identity. Finally, we present a model for mitosis in Volvox. Our study reveals enormous dynamics, clarifies spatio-temporal relationships of subcellular structures, and provides insight into the evolution of cell division.
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Affiliation(s)
- Eva Laura von der Heyde
- Department of Cellular and Developmental Biology of Plants, University of Bielefeld, Universitätsstr. 25, 33615 Bielefeld, Germany
| | - Armin Hallmann
- Department of Cellular and Developmental Biology of Plants, University of Bielefeld, Universitätsstr. 25, 33615 Bielefeld, Germany
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15
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Gibieža P, Petrikaitė V. The regulation of actin dynamics during cell division and malignancy. Am J Cancer Res 2021; 11:4050-4069. [PMID: 34659876 PMCID: PMC8493394] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2021] [Accepted: 07/29/2021] [Indexed: 06/13/2023] Open
Abstract
Actin is the most abundant protein in almost all the eukaryotic cells. Actin amino acid sequences are highly conserved and have not changed a lot during the progress of evolution, varying by no more than 20% in the completely different species, such as humans and algae. The network of actin filaments plays a crucial role in regulating cells' cytoskeleton that needs to undergo dynamic tuning and structural changes in order for various functional processes, such as cell motility, migration, adhesion, polarity establishment, cell growth and cell division, to take place in live cells. Owing to its fundamental role in the cell, actin is a prominent regulator of cell division, a process, whose success directly depends on morphological changes of actin cytoskeleton and correct segregation of duplicated chromosomes. Disorganization of actin framework during the last stage of cell division, known as cytokinesis, can lead to multinucleation and formation of polyploidy in post-mitotic cells, eventually developing into cancer. In this review, we will cover the principles of actin regulation during cell division and discuss how the control of actin dynamics is altered during the state of malignancy.
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Affiliation(s)
- Paulius Gibieža
- Laboratory of Drug Targets Histopathology, Institute of Cardiology, Lithuanian University of Health Sciences Kaunas, LT-50162, Lithuania
| | - Vilma Petrikaitė
- Laboratory of Drug Targets Histopathology, Institute of Cardiology, Lithuanian University of Health Sciences Kaunas, LT-50162, Lithuania
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16
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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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17
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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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18
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Actin on and around the Nucleus. Trends Cell Biol 2020; 31:211-223. [PMID: 33376040 DOI: 10.1016/j.tcb.2020.11.009] [Citation(s) in RCA: 60] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2020] [Revised: 11/15/2020] [Accepted: 11/19/2020] [Indexed: 12/14/2022]
Abstract
Actin plays roles in many important cellular processes, including cell motility, organelle movement, and cell signaling. The discovery of transmembrane actin-binding proteins at the outer nuclear membrane (ONM) raises the exciting possibility that actin can play a role in direct force transmission to the nucleus and the genome at its interior. Actin-dependent nucleus displacement was first described a decade ago. We are now gaining a more detailed understanding of its mechanisms, as well as new roles for actin during mitosis and meiosis, for gene expression, and in the cell's response to mechanical stimuli. Here we review these recent developments, the actin-binding proteins involved, the tissue specificity of these mechanisms, and methods developed to reconstitute and study this interaction in vitro.
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19
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Castro D, Nunes V, Lima JT, Ferreira JG, Aguiar P. Trackosome: a computational toolbox to study the spatiotemporal dynamics of centrosomes, nuclear envelope and cellular membrane. J Cell Sci 2020; 133:jcs.252254. [PMID: 33199521 DOI: 10.1242/jcs.252254] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2020] [Accepted: 11/02/2020] [Indexed: 11/20/2022] Open
Abstract
During the initial stages of mitosis, multiple mechanisms drive centrosome separation and positioning. How they are coordinated to promote centrosome migration to opposite sides of the nucleus remains unclear. Here, we present Trackosome, an open-source image analysis software for tracking centrosomes and reconstructing nuclear and cellular membranes, based on volumetric live-imaging data. The toolbox runs in MATLAB and provides a graphical user interface for easy access to the tracking and analysis algorithms. It provides detailed quantification of the spatiotemporal relationships between centrosomes, nuclear envelope and cellular membrane, and can also be used to measure the dynamic fluctuations of the nuclear envelope. These fluctuations are important because they are related to the mechanical forces exerted on the nucleus by its adjacent cytoskeletal structures. Unlike previous algorithms based on circular or elliptical approximations, Trackosome measures membrane movement in a model-free condition, making it viable for irregularly shaped nuclei. Using Trackosome, we demonstrate significant correlations between the movements of the centrosomes, and identify specific oscillation modes of the nuclear envelope. Overall, Trackosome is a powerful tool that can be used to help unravel new elements in the spatiotemporal dynamics of subcellular structures.
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Affiliation(s)
- Domingos Castro
- i3S - Instituto de Investigação e Inovação em Saúde, Universidade do Porto, 4200-135 Porto, Portugal
| | - Vanessa Nunes
- i3S - Instituto de Investigação e Inovação em Saúde, Universidade do Porto, 4200-135 Porto, Portugal
| | - Joana T Lima
- i3S - Instituto de Investigação e Inovação em Saúde, Universidade do Porto, 4200-135 Porto, Portugal
| | - Jorge G Ferreira
- i3S - Instituto de Investigação e Inovação em Saúde, Universidade do Porto, 4200-135 Porto, Portugal .,Departamento de Biomedicina, Faculdade de Medicina, Universidade do Porto, 4200-450 Porto, Portugal
| | - Paulo Aguiar
- i3S - Instituto de Investigação e Inovação em Saúde, Universidade do Porto, 4200-135 Porto, Portugal
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20
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Bornens M. Centrosome organization and functions. Curr Opin Struct Biol 2020; 66:199-206. [PMID: 33338884 DOI: 10.1016/j.sbi.2020.11.002] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2020] [Revised: 10/23/2020] [Accepted: 11/03/2020] [Indexed: 02/06/2023]
Abstract
The centrosome, discovered near 1875, was named by Boveri when proposing the chromosomal theory of heredity. After a long eclipse, a considerable amount of molecular data has been accumulated on the centrosome and its biogenesis in the last 30 years, summarized regularly in excellent reviews. Major questions are still at stake in 2021 however, as we lack a comprehensive view of the centrosome functions. I will first try to see how progress towards a unified view of the role of centrosomes during evolution is possible, and then review recent data on only some of the many important questions raised by this organelle.
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Affiliation(s)
- Michel Bornens
- Institut Curie, PSL University, CNRS - UMR 144, 75005 Paris, France.
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21
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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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