المؤلفون: Katrukha, Eugene A, Jurriens, Daphne, Salas Pastene, Desiree M, Kapitein, Lukas C, Sub Cell Biology, Celbiologie

المساهمون: Sub Cell Biology, Celbiologie

المصدر: eLife, 10, 1. eLife Sciences Publications
elife
eLife, Vol 10 (2021)
eLife

مصطلحات موضوعية: Male, Kinesins, super-resolution, Hippocampus, Cell membrane, Neurons/cytology, 0302 clinical medicine, Tubulin, Biology (General), Cytoskeleton, Neurons, 0303 health sciences, Absolute number, Chemistry, General Neuroscience, STED microscopy, cytoskeleton, Acetylation, General Medicine, medicine.anatomical_structure, Microtubules/metabolism, Medicine, Female, expansion microscopy, Research Article, Kinesins/metabolism, QH301-705.5, hippocampal neurons, Science, Hippocampus/metabolism, General Biochemistry, Genetics and Molecular Biology, microtubules, Motor protein, 03 medical and health sciences, Microtubule, Detyrosination, medicine, Animals, Protein Processing, 030304 developmental biology, General Immunology and Microbiology, Microtubule cytoskeleton, Post-Translational, Dendritic shaft, Cell Biology, Tubulin/metabolism, Superresolution, Rats, Biophysics, Rat, Developmental biology, Protein Processing, Post-Translational, 030217 neurology & neurosurgery, Intracellular transport, Developmental Biology

الوصف: The neuronal microtubule cytoskeleton underlies the polarization and proper functioning of neurons, amongst others by providing tracks for motor proteins that drive intracellular transport. Different subsets of neuronal microtubules, varying in composition, stability, and motor preference, are known to exist, but the high density of microtubules has so far precluded mapping their relative abundance and three-dimensional organization. Here, we use different super-resolution techniques (STED, Expansion Microscopy) to explore the nanoscale organization of the neuronal microtubule network in rat hippocampal neurons. This revealed that in dendrites acetylated microtubules are enriched in the core of the dendritic shaft, while tyrosinated microtubules are enriched near the plasma membrane, thus forming a shell around the acetylated microtubules. Moreover, using a novel analysis pipeline we quantified the absolute number of acetylated and tyrosinated microtubules within dendrites and found that they account for 65–75% and ~20–30% of all microtubules, respectively, leaving only few microtubules that do not fall in either category. Because these different microtubule subtypes facilitate different motor proteins, these novel insights help to understand the spatial regulation of intracellular transport.
eLife digest Cells in the body need to control the position of the molecules and other components inside them. To do this, they use a system of proteins that work a bit like a road network. The ‘roads’ are tubular structures known as microtubules, while ‘vehicles’ are transporters, called motor proteins, that ‘walk’ along the microtubules. Microtubule networks are important in all cells, but especially in neurons, which can grow very large. These cells have tree-like branches called dendrites that receive messages from other neurons. Dendrites contain different types of microtubules with many chemical modifications. These modifications consist of specific molecules or ‘groups’ becoming attached to or removed from the microtubules to change their properties – for example, microtubules can be ‘acetylated’ or ‘detyrosinated’. Motor proteins prefer different kinds of microtubules, and so understanding transport inside cells involves creating a precise roadmap showing how many of each type of microtubule exist and where they go. Using different super-resolution microscopy techniques, Katrukha et al. created maps of the microtubules in rat neurons. These show that acetylated microtubules form a core in the centre of the dendrites, while tyrosinated microtubules (which did not undergo detyrosination) line the cell membrane of the dendrites. Katrukha et al. then used the maps to determine that acetylated microtubules account for 65 to 70% of all microtubules, while tyrosinated microtubules make up 20 to 30%. This means that most microtubules fall into these two categories. The work by Katrukha et al. provides one of the first quantitative estimates of the relative amount of acetylated and tyrosinated microtubules, starting to shed light on how cells control their transport network. This could ultimately allow researchers to explore how transport changes in health and disease.

وصف الملف: application/pdf

الوصول الحر: https://explore.openaire.eu/search/publication?articleId=doi_dedup___::6163981e83876b16d85d1db7b2c5c941Test
https://dspace.library.uu.nl/handle/1874/419552Test

المؤلفون: Judith B Fuelle, André Voelzmann, Laura Anne Lowery, Ines Hahn, Andreas Prokop, Natalia Sanchez-Soriano, Paula G. Slater, Jill Parkin

المصدر: PLoS Genetics, Vol 17, Iss 7, p e1009647 (2021)
Hahn, I, Voelzmann, A, Parkin, J, Fülle, J B, Slater, P G, Lowery, L A, Sanchez-Soriano, N & Prokop, A 2021, ' Tau, XMAP215/Msps and Eb1 co-operate interdependently to regulate microtubule polymerisation and bundle formation in axons ', PLoS Genetics, vol. 17, no. 7, 1009647 . https://doi.org/10.1371/journal.pgen.1009647Test
PLoS Genetics
PLOS GENETICS

مصطلحات موضوعية: 0301 basic medicine, Cancer Research, Life Cycles, Drosophila Proteins/metabolism, Xenopus, Mutant, Neurons/metabolism, Xenopus Proteins, QH426-470, Microtubules, Polymerization, Xenopus laevis, 0302 clinical medicine, Nerve Fibers, Larvae, Animal Cells, Drosophila Proteins, Axon, Genetics (clinical), Cytoskeleton, Neurons, 0303 health sciences, Chemistry, Drosophila Melanogaster, Neurodegeneration, Chemical Reactions, Eukaryota, Animal Models, Axon growth, Cell biology, Insects, Phenotypes, medicine.anatomical_structure, Experimental Organism Systems, Microtubules/metabolism, Physical Sciences, Vertebrates, Microtubule-Associated Proteins/metabolism, Frogs, Drosophila, Drosophila melanogaster, Cellular Types, Cellular Structures and Organelles, Xenopus laevis/metabolism, Microtubule-Associated Proteins, Research Article, Arthropoda, tau Proteins, Axons/metabolism, macromolecular substances, Biology, Xenopus Proteins/metabolism, Research and Analysis Methods, Drosophila melanogaster/metabolism, Amphibians, 03 medical and health sciences, Model Organisms, tau Proteins/metabolism, Microtubule, medicine, Genetics, Animals, Molecular Biology, Ecology, Evolution, Behavior and Systematics, 030304 developmental biology, fungi, Organisms, Biology and Life Sciences, Cell Biology, medicine.disease, biology.organism_classification, Polymer Chemistry, Invertebrates, Axons, 030104 developmental biology, Bundle, Cellular Neuroscience, Axoplasmic transport, Animal Studies, Zoology, Entomology, 030217 neurology & neurosurgery, Neuroscience, Developmental Biology

الوصف: The formation and maintenance of microtubules requires their polymerisation, but little is known about how this polymerisation is regulated in cells. Focussing on the essential microtubule bundles in axons of Drosophila and Xenopus neurons, we show that the plus-end scaffold Eb1, the polymerase XMAP215/Msps and the lattice-binder Tau co-operate interdependently to promote microtubule polymerisation and bundle organisation during axon development and maintenance. Eb1 and XMAP215/Msps promote each other’s localisation at polymerising microtubule plus-ends. Tau outcompetes Eb1-binding along microtubule lattices, thus preventing depletion of Eb1 tip pools. The three factors genetically interact and show shared mutant phenotypes: reductions in axon growth, comet sizes, comet numbers and comet velocities, as well as prominent deterioration of parallel microtubule bundles into disorganised curled conformations. This microtubule curling is caused by Eb1 plus-end depletion which impairs spectraplakin-mediated guidance of extending microtubules into parallel bundles. Our demonstration that Eb1, XMAP215/Msps and Tau co-operate during the regulation of microtubule polymerisation and bundle organisation, offers new conceptual explanations for developmental and degenerative axon pathologies.
Author summary Axons are the up-to-meter-long processes of nerve cells that form the cables wiring our nervous system. Once established, they must survive for a century in humans. Improper extension of axons leads to neurodevelopmental defects, and age- or disease-related neurodegeneration usually starts in axons. Axonal architecture and function depend on bundles of filamentous polymers, called microtubules. These bundles run all along the axonal core, and their disruption correlates with axon decay. How these axonal microtubule bundles are formed and dynamically maintained is little understood. We bridge this knowledge gap by studying how different classes of microtubule-binding proteins may regulate these processes. Here we show how three proteins of very different function, Eb1, XMAP215 and Tau, cooperate intricately to promote the polymerisation processes that form new microtubules during axon development and maintenance. If either protein is dysfunctional, polymerisation is slowed down and newly forming microtubules fail to align into proper bundles. These findings provide new explanations for the decay of microtubule bundles, hence axons. To unravel these mechanisms, we used the fruit fly as a powerful organism for biomedical discoveries. We then showed that the same mechanisms act in frog axons, suggesting they might apply also to humans.

وصف الملف: application/pdf

الوصول الحر: https://explore.openaire.eu/search/publication?articleId=doi_dedup___::d17abca2879f65f60eb95a33dfe6642bTest
https://doaj.org/article/c5e8e8f422334f6baa0209cb9072db39Test

المؤلفون: Helder Maiato, Danilo Lopes

المساهمون: Instituto de Investigação e Inovação em Saúde

المصدر: Cells
Cells, Vol 9, Iss 2356, p 2356 (2020)

مصطلحات موضوعية: Review, tubulin post-translational modifications, Microtubules, Chromosome segregation, 0302 clinical medicine, Cell Movement, Tubulin, Chromosome instability, Neoplasms, Mitosis / genetics, Neoplasms / etiology, Protein Isoforms, lcsh:QH301-705.5, Neoplasms / metabolism, Cell Movement / genetics, 0303 health sciences, biology, General Medicine, Cell biology, 030220 oncology & carcinogenesis, Disease Susceptibility, microtubule, Microtubules / metabolism, chromosomal instability, Context (language use), macromolecular substances, Spindle Apparatus, 03 medical and health sciences, Microtubule, Detyrosination, biochemistry, Humans, cancer, Neoplasm Invasiveness, Mitosis, 030304 developmental biology, Cytokinesis, Centrosome, mitosis, Neoplasms / pathology, Tubulin / metabolism, Centrosome / metabolism, Spindle apparatus, Tubulin / genetics, lcsh:Biology (General), Spindle Apparatus / metabolism, tubulin code, biology.protein, Protein Processing, Post-Translational

الوصف: The "tubulin code" combines different a/ß-tubulin isotypes with several post-translational modifications (PTMs) to generate microtubule diversity in cells. During cell division, specific microtubule populations in the mitotic spindle are differentially modified, but only recently, the functional significance of the tubulin code, with particular emphasis on the role specified by tubulin PTMs, started to be elucidated. This is the case of a-tubulin detyrosination, which was shown to guide chromosomes during congression to the metaphase plate and allow the discrimination of mitotic errors, whose correction is required to prevent chromosomal instability-a hallmark of human cancers implicated in tumor evolution and metastasis. Although alterations in the expression of certain tubulin isotypes and associated PTMs have been reported in human cancers, it remains unclear whether and how the tubulin code has any functional implications for cancer cell properties. Here, we review the role of the tubulin code in chromosome segregation during mitosis and how it impacts cancer cell properties. In this context, we discuss the existence of an emerging "cancer tubulin code" and the respective implications for diagnostic, prognostic and therapeutic purposes. Danilo Lopes is a student of Programa de Pós-Graduação Ciência para o Desenvolvimento (PGCD) from Instituto Gulbenkian de Ciência (IGC), Oeiras, Portugal and recipient of a studentship (SFRH/BD/135077/2017) from Fundação para a Ciência e a Tecnologia of Portugal. Work in the laboratory of H.M. is funded by the European Research Council (ERC) under the European Union’s Horizon 2020 Research and Innovation Programme (grant agreement No 681443).

وصف الملف: application/pdf

الوصول الحر: https://explore.openaire.eu/search/publication?articleId=doi_dedup___::02a10aacc345646ff952f29ff23861b1Test
https://pubmed.ncbi.nlm.nih.gov/33114575Test

المؤلفون: Carsten Janke, Ana L. Pereira, Suvranta K. Tripathy, Anatoly V. Zaytsev, Maria M. Magiera, Helder Maiato, Ekaterina L. Grishchuk, Marin Barisic, Ricardo Silva e Sousa

المساهمون: Instituto de Investigação e Inovação em Saúde

المصدر: Repositório Científico de Acesso Aberto de Portugal
Repositório Científico de Acesso Aberto de Portugal (RCAAP)
instacron:RCAAP

مصطلحات موضوعية: Mitosis, macromolecular substances, Biology, Spindle pole body, 03 medical and health sciences, 0302 clinical medicine, Microtubule, Cell Line, Tumor, Chromosome Segregation, Detyrosination, Humans, Sarcosine/analogs & derivatives, Non-Histone/antagonists & inhibitors, 030304 developmental biology, Genetics, Spindle Apparatus/metabolism, 0303 health sciences, Chromosomal Proteins Non-Histone/metabolism, Multidisciplinary, Kinetochore, Sarcosine/pharmacology, Tubulin/metabolism, Molecular Imaging, Spindle apparatus, Cell biology, Chromosomal Proteins, Tubulin, Microtubules/metabolism, Chromosomal Proteins Non-Histone/genetics, Bridged Bicyclo Compounds Heterocyclic/pharmacology, biology.protein, Tyrosine/metabolism, Astral microtubules, 030217 neurology & neurosurgery

الوصف: Before chromosomes segregate into daughter cells, they align at the mitotic spindle equator, a process known as chromosome congression. Centromere-associated protein E (CENP-E)/Kinesin-7 is a microtubule plus-end-directed kinetochore motor required for congression of pole-proximal chromosomes. Because the plus-ends of many astral microtubules in the spindle point to the cell cortex, it remains unknown how CENP-E guides pole-proximal chromosomes specifically toward the equator. We found that congression of pole-proximal chromosomes depended on specific posttranslational detyrosination of spindle microtubules that point to the equator. In vitro reconstitution experiments demonstrated that CENP-E-dependent transport was strongly enhanced on detyrosinated microtubules. Blocking tubulin tyrosination in cells caused ubiquitous detyrosination of spindle microtubules, and CENP-E transported chromosomes away from spindle poles in random directions. Thus, CENP-E-driven chromosome congression is guided by microtubule detyrosination. We thank F. I. Ataullakhanov for help with the laser trap and data analysis; A. Kiyatkin, V. Mustyatsa, M. Molodtsov, A. Gautreau, G. Lakisic, and M. Barisic for technical assistance; and members of our laboratories for stimulating discussions. This work was supported by National Institutes of Health grant R01-GM098389 and RSG-14-018-01-CCG from the American Cancer Society to E.L.G.; by the Institut Curie, the Centre National de la Recherche Scientifique, the Institut National de la Sante et de la Recherche Medicale, the L'Agence Nationale de la Recherche (ANR) award ANR-12-BSV2-0007, INCA_6517, ANR-10-LBX-0038, part of the IDEX Idex PSL, ANR-10-IDEX-0001-02 PSL to C.J.; and Fundacao Luso-Americana para o Desenvolvimento (FLAD) Life Science 2020 and PRECISE grant from the European Research Council to H.M. A.V.Z. is supported by the RAS Presidium Grants "Mechanisms of the Molecular Systems Integration," " Molecular and Cell Biology programs," and Russian Fund for Basic Research Grant 12-04-00111-a and 13-00-40188. R.S.S. is supported by a fellowship from the Programa Graduado em Areas da Biologia Basica e Aplicada (GABBA) PhD program from the University of Porto. A.L.P. is supported by fellowship SFRH/BPD/66707/2009 from Fundacao para a Ciencia e a Tecnologia of Portugal. M.B., R.S.S., S.K.T., M.M.M., C.J., E.L.G., and H.M. designed the experiments; M.B. performed all experiments in cells; M. M. M. established and performed the tubulin purification protocol from HeLa cells; R.S.S. performed single-molecule experiments; S.K.T. performed force measurements; A.L.P. provided reagents; all authors analyzed data; H.M., E.L.G., and M.B. wrote the paper, with contributions from all authors; H.M. conceived and coordinated the project. Data described can be found in the main figures and supplementary materials. The authors declare no conflict of interests.

وصف الملف: application/pdf

الوصول الحر: https://explore.openaire.eu/search/publication?articleId=doi_dedup___::ae16d669e28eecb53df4c0b4cb413103Test
https://doi.org/10.1126/science.aaa5175Test

المؤلفون: Benjamin T. Goult, York-Christoph Ammon, Anna Akhmanova, Albert J. R. Heck, A. F. Maarten Altelaar, Harm Post, Rosemarie E. Gough, Dieudonnée van de Willige, Benjamin P. Bouchet, Guillaume Jacquemet

المصدر: eLife, Vol 5 (2016)
eLife
Elife, 5:e18124. eLife Sciences Publications, Ltd

مصطلحات موضوعية: 0301 basic medicine, Role of cell adhesions in neural development, Microtubules, Tumor Suppressor Proteins/metabolism, Extracellular matrix, 0302 clinical medicine, focal adhesion, Biology (General), 0303 health sciences, biology, Chemistry, General Neuroscience, Adaptor Proteins, Signal transducing adaptor protein, General Medicine, Biophysics and Structural Biology, Cell biology, Microtubules/metabolism, Medicine, Cortical microtubule, Research Article, Human, microtubule, QH301-705.5, Science, Integrin, macromolecular substances, ta3111, General Biochemistry, Genetics and Molecular Biology, Focal adhesion, 03 medical and health sciences, QH301, Microtubule, Cell Adhesion, Humans, Actin, 030304 developmental biology, Adaptor Proteins, Signal Transducing, Focal Adhesions, General Immunology and Microbiology, Point mutation, talin, Focal Adhesions/metabolism, Signal Transducing, ta1182, KANK, Cell Biology, Cytoskeletal Proteins, HEK293 Cells, 030104 developmental biology, Biophysics, Talin/metabolism, biology.protein, 030217 neurology & neurosurgery, HeLa Cells

الوصف: The cross-talk between dynamic microtubules and integrin-based adhesions to the extracellular matrix plays a crucial role in cell polarity and migration. Microtubules regulate the turnover of adhesion sites, and, in turn, focal adhesions promote the cortical microtubule capture and stabilization in their vicinity, but the underlying mechanism is unknown. Here, we show that cortical microtubule stabilization sites containing CLASPs, KIF21A, LL5β and liprins are recruited to focal adhesions by the adaptor protein KANK1, which directly interacts with the major adhesion component, talin. Structural studies showed that the conserved KN domain in KANK1 binds to the talin rod domain R7. Perturbation of this interaction, including a single point mutation in talin, which disrupts KANK1 binding but not the talin function in adhesion, abrogates the association of microtubule-stabilizing complexes with focal adhesions. We propose that the talin-KANK1 interaction links the two macromolecular assemblies that control cortical attachment of actin fibers and microtubules. DOI: http://dx.doi.org/10.7554/eLife.18124.001Test
eLife digest Animal cells are organized into tissues and organs. A scaffold-like framework outside of the cells called the extracellular matrix provides support to the cells and helps to hold them in place. Cells attach to the extracellular matrix via structures called focal adhesions on the cell surface; these structures contain a protein called talin. For a cell to be able to move, the existing focal adhesions must be broken down and new adhesions allowed to form. This process is regulated by the delivery and removal of different materials along fibers called microtubules. Microtubules can usually grow and shrink rapidly, but near focal adhesions they are captured at the surface of the cell and become more stable. However, it is not clear how focal adhesions promote microtubule capture and stability. Bouchet et al. found that a protein called KANK1 binds to the focal adhesion protein talin in human cells grown in a culture dish. This allows KANK1 to recruit microtubules to the cell surface around the focal adhesions by binding to particular proteins that are associated with microtubules. Disrupting the interaction between KANK1 and talin by making small alterations in these two proteins blocked the ability of focal adhesions to capture surrounding microtubules. The next step following on from this work will be to find out whether this process also takes place in the cells within an animal’s body, such as a fly or a mouse. DOI: http://dx.doi.org/10.7554/eLife.18124.002Test

وصف الملف: application/pdf

الوصول الحر: https://explore.openaire.eu/search/publication?articleId=doi_dedup___::bcf8514e39a2d26f25dff8b8361415afTest
https://doi.org/10.7554/eLife.18124Test

المؤلفون: René Holtackers, Mukta Belwal, Samuel Wieser, Ana C. Amaro, Julien Mouysset, Nunu Mchedlishvili, Patrick Meraldi

المصدر: Journal of Cell Science, Vol. 125, No Pt 4 (2012) pp. 906-18
Journal of cell science

مصطلحات موضوعية: Prometaphase, M Phase Cell Cycle Checkpoints, Chromosomal Proteins, Non-Histone, Nuclear Envelope, Cell Cycle Proteins, Spindle Apparatus, Biology, Microtubule-Associated Proteins/deficiency/metabolism, Microtubules, Chromosome segregation, 03 medical and health sciences, 0302 clinical medicine, Microtubule, Chromosome Segregation, Humans, Kinetochores, Mitosis, Nuclear Envelope/metabolism, 030304 developmental biology, Centrosome, 0303 health sciences, Kinetochore, Cell Biology, Cell biology, Cell Cycle Proteins/deficiency/metabolism, Centrosome/metabolism, Kinetochores/metabolism, Microtubules/metabolism, Centrosome separation, Microtubule-Associated Proteins, Mitotic Spindle Apparatus/metabolism, 030217 neurology & neurosurgery, HeLa Cells

الوصف: At the onset of mitosis, cells need to break down their nuclear envelope, form a bipolar spindle and attach the chromosomes to microtubules via kinetochores. Previous studies have shown that spindle bipolarization can occur either before or after nuclear envelope breakdown. In the latter case, early kinetochore–microtubule attachments generate pushing forces that accelerate centrosome separation. However, until now, the physiological relevance of this prometaphase kinetochore pushing force was unknown. We investigated the depletion phenotype of the kinetochore protein CENP-L, which we find to be essential for the stability of kinetochore microtubules, for a homogenous poleward microtubule flux rate and for the kinetochore pushing force. Loss of this force in prometaphase not only delays centrosome separation by 5–6 minutes, it also causes massive chromosome alignment and segregation defects due to the formation of syntelic and merotelic kinetochore–microtubule attachments. By contrast, CENP-L depletion has no impact on mitotic progression in cells that have already separated their centrosomes at nuclear envelope breakdown. We propose that the kinetochore pushing force is an essential safety mechanism that favors amphitelic attachments by ensuring that spindle bipolarization occurs before the formation of the majority of kinetochore–microtubule attachments.

الوصول الحر: https://explore.openaire.eu/search/publication?articleId=doi_dedup___::f90b7f1bfc640f0226f7fc8e71237e7bTest
https://doi.org/10.1242/jcs.091967Test

المؤلفون: Helder Maiato, Patrick Meraldi, António J. Pereira, Marin Barisic, Reinhard Sigl, Stephan Geley, Ana C. Amaro, Veronika Rauch, Ulrike Kutay, Chia Huei Tan, Cornelia Wandke, Frank Wolf

المصدر: The Journal of cell biology
The Journal of Cell Biology
The Journal of Cell Biology, Vol. 198, No 5 (2012) pp. 847-63
The Journal of Cell Biology, 198 (5)

مصطلحات موضوعية: Metaphase/physiology, Xenopus, Kinesins, Cell Cycle Proteins, Xenopus Proteins, Microtubules, chemistry.chemical_compound, Chromosome Segregation, Mad2 Proteins, Kinesin/metabolism, Kinetochores, Research Articles, Anaphase, 0303 health sciences, DNA-Binding Proteins/metabolism, Kinetochore, 030302 biochemistry & molecular biology, Nuclear Proteins, Anaphase/physiology, Cell biology, DNA-Binding Proteins, Nocodazole, Microtubules/metabolism, Mitotic Spindle Apparatus/metabolism, Mitosis, Spindle Apparatus, Biology, Xenopus Proteins/metabolism, Article, Cell Line, Kinetochore microtubule, 03 medical and health sciences, Calcium-Binding Proteins/metabolism, Cell Line, Tumor, mental disorders, Animals, Humans, Cell Cycle Checkpoints/physiology, ddc:612, Metaphase, 030304 developmental biology, Nuclear Proteins/metabolism, Cell Cycle Proteins/metabolism, Repressor Proteins/metabolism, Calcium-Binding Proteins, Cell Biology, Cell Cycle Checkpoints, HCT116 Cells, Mitosis/physiology, Spindle apparatus, Repressor Proteins, Kinetochores/metabolism, HEK293 Cells, chemistry, Chromosome Segregation/physiology, HeLa Cells

الوصف: The Journal of Cell Biology, 198 (5)
ISSN:0021-9525
ISSN:1540-8140

وصف الملف: application/application/pdf

الوصول الحر: https://explore.openaire.eu/search/publication?articleId=doi_dedup___::84e40f4fd0ade91f056cd8cc3353818cTest

المؤلفون: Andrew D. McAinsh, Patrick Meraldi

المصدر: Seminars in Cell and Developmental Biology, Vol. 22, No 9 (2011) pp. 946-52
Seminars in cell & developmental biology

مصطلحات موضوعية: Chromosome movement, Cell division, Chromosomal Proteins, Non-Histone, Centromere, Biology, Microtubules, Kinetochore microtubule, 03 medical and health sciences, 0302 clinical medicine, Chromosomal Proteins, Non-Histone/genetics/metabolism, Humans, Kinetochores, Mitosis, 030304 developmental biology, Genetics, 0303 health sciences, Kinetochore, Chromosome, Cell Biology, Cell biology, Spindle apparatus, Models, Structural, Kinetochores/metabolism, Microtubules/metabolism, Centromere/metabolism, 030217 neurology & neurosurgery, Developmental Biology

الوصف: For over 70 years, chromosomes have been known to oscillate back-and-forth on the metaphase plate. These movements are directed by kinetochores, the microtubule-attachment complexes on centromeres that regulate the dynamics of bound spindle microtubules. Recent evidence shows that the CCAN (Constitutive Centromere Associated Network) kinetochore network, which directly binds centromeric nucleosomes, plays a crucial role in the control of kinetochore microtubule dynamics. Here we review how this 15-subunit protein network functions within the kinetochore machinery, how it may adapt dynamically both in time and in space to the functional requirements necessary for controlled and faithful chromosome movements during cell division, and how this conserved protein network may have evolved in organisms with different cell division machineries.

الوصول الحر: https://explore.openaire.eu/search/publication?articleId=doi_dedup___::971d18180cb2bf5d1298a43f6dd81ed1Test
https://doi.org/10.1016/j.semcdb.2011.09.016Test

المؤلفون: Mayya Meriane, Emmanuel Vignal, Cécile Gauthier-Rouvière, Pierre Roux, Philippe Fort, Philippe Montcourier

المساهمون: Institut de Génétique Moléculaire de Montpellier (IGMM), Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM), Centre de recherches de biochimie macromoléculaire (CRBM), Centre National de la Recherche Scientifique (CNRS)-IFR122-Université Montpellier 2 - Sciences et Techniques (UM2)-Université Montpellier 1 (UM1), Dynamique moléculaire des interactions membranaires (DMIM), Centre National de la Recherche Scientifique (CNRS)-Université Montpellier 2 - Sciences et Techniques (UM2), Institut de biologie et chimie des protéines [Lyon] (IBCP), Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS)

المصدر: Molecular Biology of the Cell
Molecular Biology of the Cell, American Society for Cell Biology, 1998, 9 (6), pp.1379-1394. ⟨10.1091/mbc.9.6.1379⟩
Molecular Biology of the Cell, American Society for Cell Biology, 1998, 9 (6), pp.1379--94. ⟨10.1091/mbc.9.6.1379⟩

مصطلحات موضوعية: rho GTP-Binding Proteins, MESH: 3T3 Cells, MESH: rac GTP-Binding Proteins, Cell Cycle Proteins, [SDV.BC.BC]Life Sciences [q-bio]/Cellular Biology/Subcellular Processes [q-bio.SC], [SDV.BID.SPT]Life Sciences [q-bio]/Biodiversity/Systematics, Phylogenetics and taxonomy, Microtubules, GTP Phosphohydrolases, Mice, MESH: Animals, cdc42 GTP-Binding Protein, Cytoskeleton, Platelet-Derived Growth Factor, 0303 health sciences, biology, MESH: Microtubules, MESH: Platelet-Derived Growth Factor, 030302 biochemistry & molecular biology, MESH: Transcription Factors, 3T3 Cells, rac GTP-Binding Proteins, Cell biology, 3T3 Cells Actins/metabolism Animals Bradykinin/pharmacology Cell Cycle Proteins/*metabolism Cell Line Cytoskeleton/physiology GTP Phosphohydrolases/genetics/*metabolism GTP-Binding Proteins/*metabolism Green Fluorescent Proteins Luminescent Proteins/metabolism Mice Microtubules/metabolism Platelet-Derived Growth Factor/pharmacology Rats Recombinant Fusion Proteins/genetics/metabolism Transcription Factors/genetics/*metabolism cdc42 GTP-Binding Protein rac GTP-Binding Proteins, MESH: Luminescent Proteins, Lamellipodium, Filopodia, MESH: GTP Phosphohydrolases, MESH: GTP-Binding Proteins, MESH: Rats, Membrane ruffling, Recombinant Fusion Proteins, Green Fluorescent Proteins, [SDV.CAN]Life Sciences [q-bio]/Cancer, RAC1, Rho family of GTPases, MESH: Actins, Bradykinin, Article, Cell Line, 03 medical and health sciences, MESH: Cell Cycle Proteins, MESH: Green Fluorescent Proteins, GTP-Binding Proteins, MESH: Cytoskeleton, MESH: Recombinant Fusion Proteins, Animals, [SDV.BBM]Life Sciences [q-bio]/Biochemistry, Molecular Biology, MESH: Mice, Molecular Biology, 030304 developmental biology, MESH: Bradykinin, MESH: cdc42 GTP-Binding Protein, [SDV.BBM.BM]Life Sciences [q-bio]/Biochemistry, Molecular Biology/Molecular biology, Cell Biology, Apical membrane, Actins, MESH: Cell Line, Rats, Luminescent Proteins, [SDV.BDD.EO]Life Sciences [q-bio]/Development Biology/Embryology and Organogenesis, biology.protein, RhoG, Transcription Factors

الوصف: International audience; RhoG is a member of the Rho family of GTPases that shares 72% and 62% sequence identity with Rac1 and Cdc42Hs, respectively. We have expressed mutant RhoG proteins fused to the green fluorescent protein and analyzed subsequent changes in cell surface morphology and modifications of cytoskeletal structures. In rat and mouse fibroblasts, green fluorescent protein chimera and endogenous RhoG proteins colocalize according to a tubular cytoplasmic pattern, with perinuclear accumulation and local concentration at the plasma membrane. Constitutively active RhoG proteins produce morphological and cytoskeletal changes similar to those elicited by a simultaneous activation of Rac1 and Cdc42Hs, i.e., the formation of ruffles, lamellipodia, filopodia, and partial loss of stress fibers. In addition, RhoG and Cdc42Hs promote the formation of microvilli at the cell apical membrane. RhoG-dependent events are not mediated through a direct interaction with Rac1 and Cdc42Hs targets such as PAK-1, POR1, or WASP proteins but require endogenous Rac1 and Cdc42Hs activities: coexpression of a dominant negative Rac1 impairs membrane ruffling and lamellipodia but not filopodia or microvilli formation. Conversely, coexpression of a dominant negative Cdc42Hs only blocks microvilli and filopodia, but not membrane ruffling and lamellipodia. Microtubule depolymerization upon nocodazole treatment leads to a loss of RhoG protein from the cell periphery associated with a reversal of the RhoG phenotype, whereas PDGF or bradykinin stimulation of nocodazole-treated cells could still promote Rac1- and Cdc42Hs-dependent cytoskeletal reorganization. Therefore, our data demonstrate that RhoG controls a pathway that requires the microtubule network and activates Rac1 and Cdc42Hs independently of their growth factor signaling pathways.

الوصول الحر: https://explore.openaire.eu/search/publication?articleId=doi_dedup___::77eec23146dd1e2d1ddaf7f836891649Test
https://doi.org/10.1091/mbc.9.6.1379Test

المؤلفون: Arnaud Echard, Jean-Yves Tinevez, Elizabeth Faris Crowell

المساهمون: Trafic membranaire et Division cellulaire - Membrane Traffic and Cell Division, Institut Pasteur [Paris]-Centre National de la Recherche Scientifique (CNRS), Imagerie Dynamique (Plate-Forme) (PFID), Institut Pasteur [Paris], E.F.C. was supported by a fellowship from the French Association pour la Recherche sur le Cancer (ARC). This work was supported by the Institut PASTEUR (G5 program), the CNRS, the Schlumberger Foundation for Education and Research and the Fondation pour la Recherche Médicale (FRM Team)., We are indebted to Jean‐Luc Lecouey (Laboratoire de Physique Corpusculaire, Caen) for helpful discussions and advice on the model. We gratefully acknowledge Hua Wong (Computational Imaging and Modeling Group, Institut Pasteur, Paris) and Mickaël Machicoane (Membrane Traffic and Cell Division Lab, Institut Pasteur, Paris) for critical reading of the manuscript. We thank E. Laplantine (Signalisation moléculaire et Activation cellulaire Lab, Institut Pasteur, Paris) for sharing reagents., Institut Pasteur [Paris] (IP)-Centre National de la Recherche Scientifique (CNRS), Institut Pasteur [Paris] (IP)

المصدر: BioEssays
BioEssays, Wiley-VCH Verlag, 2013, 35 (5), pp.472-481. ⟨10.1002/bies.201200132⟩
BioEssays, 2013, 35 (5), pp.472-481. ⟨10.1002/bies.201200132⟩

مصطلحات موضوعية: cell division, MESH: Cell Differentiation, autophagy, Cell division, [SDV]Life Sciences [q-bio], Population, MESH: Cell Membrane / metabolism, [SDV.BC]Life Sciences [q-bio]/Cellular Biology, Biology, General Biochemistry, Genetics and Molecular Biology, remnant, 03 medical and health sciences, 0302 clinical medicine, MESH: Cell Proliferation, MESH: Autophagy, MESH: Microtubules / metabolism, MESH: Animals, education, MESH: Mice, 030304 developmental biology, 0303 health sciences, education.field_of_study, model, MESH: Humans, Autophagy, digestive, oral, and skin physiology, MESH: Models, Biological, MESH: Research Design, MESH: Time Factors, Anatomy, MESH: Fibroblasts / metabolism, Cell biology, Midbody, Bridge (graph theory), surgical procedures, operative, midbody, MESH: HeLa Cells, MESH: Cytokinesis, MESH: Fibroblasts / cytology, 030217 neurology & neurosurgery, Cytokinesis, Degradation (telecommunications)

الوصف: International audience; When a cell divides, it produces two daughter cells initially connected by a cytokinesis bridge, which is eventually cut through abscission. One of the two daughter cells inherits a bridge "remnant", which has been proposed to be degraded by autophagy. The fate and function of remnants is attracting increasing attention, as their accumulation appears to influence proliferation versus differentiation of the daughter cells. Here, we present a simple model for bridge and remnant turnover in a dynamic cell population. We demonstrate that remnant proportions depend on the ratio of remnant and bridge lifetimes to the cell population doubling time. Our results yield new alternative interpretations for published experimental data, leading us to believe that autophagy-independent pathways for remnant degradation may exist. In addition, using the model, we determined experimentally inaccessible parameters such as remnant lifetime. Our model proves to be a useful tool for studying bridge and remnant populations.

الوصول الحر: https://explore.openaire.eu/search/publication?articleId=doi_dedup___::cc183f56bdfecd12ec49cb176c834b23Test
https://hal-pasteur.archives-ouvertes.fr/pasteur-02616463Test