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Romeiro Motta M, Biswas S, Schaedel L. Beyond uniformity: Exploring the heterogeneous and dynamic nature of the microtubule lattice. Eur J Cell Biol 2023; 102:151370. [PMID: 37922811 DOI: 10.1016/j.ejcb.2023.151370] [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: 08/14/2023] [Revised: 10/17/2023] [Accepted: 10/26/2023] [Indexed: 11/07/2023] Open
Abstract
A fair amount of research on microtubules since their discovery in 1963 has focused on their dynamic tips. In contrast, the microtubule lattice was long believed to be highly regular and static, and consequently received far less attention. Yet, as it turned out, the microtubule lattice is neither as regular, nor as static as previously believed: structural studies uncovered the remarkable wealth of different conformations the lattice can accommodate. In the last decade, the microtubule lattice was shown to be labile and to spontaneously undergo renovation, a phenomenon that is intimately linked to structural defects and was called "microtubule self-repair". Following this breakthrough discovery, further recent research provided a deeper understanding of the lattice self-repair mechanism, which we review here. Instrumental to these discoveries were in vitro microtubule reconstitution assays, in which microtubules are grown from the minimal components required for their dynamics. In this review, we propose a shift from the term "lattice self-repair" to "lattice dynamics", since this phenomenon is an inherent property of microtubules and can happen without microtubule damage. We focus on how in vitro microtubule reconstitution assays helped us learn (1) which types of structural variations microtubules display, (2) how these structural variations influence lattice dynamics and microtubule damage caused by mechanical stress, (3) how lattice dynamics impact tip dynamics, and (4) how microtubule-associated proteins (MAPs) can play a role in structuring the lattice. Finally, we discuss the unanswered questions about lattice dynamics and how technical advances will help us tackle these questions.
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Affiliation(s)
- Mariana Romeiro Motta
- Department of Physics, Center for Biophysics, Campus A2 4, Saarland University, 66123 Saarbrücken, Germany; Laboratoire Reproduction et Développement des Plantes, Université de Lyon, École normale supérieure de Lyon, Lyon 69364, France
| | - Subham Biswas
- Department of Physics, Center for Biophysics, Campus A2 4, Saarland University, 66123 Saarbrücken, Germany
| | - Laura Schaedel
- Department of Physics, Center for Biophysics, Campus A2 4, Saarland University, 66123 Saarbrücken, Germany.
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2
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Blumrich EM, Nicholson-Fish JC, Pronot M, Davenport EC, Kurian D, Cole A, Smillie KJ, Cousin MA. Phosphatidylinositol 4-kinase IIα is a glycogen synthase kinase 3-regulated interaction hub for activity-dependent bulk endocytosis. Cell Rep 2023; 42:112633. [PMID: 37314927 DOI: 10.1016/j.celrep.2023.112633] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2022] [Revised: 04/04/2023] [Accepted: 05/25/2023] [Indexed: 06/16/2023] Open
Abstract
Phosphatidylinositol 4-kinase IIα (PI4KIIα) generates essential phospholipids and is a cargo for endosomal adaptor proteins. Activity-dependent bulk endocytosis (ADBE) is the dominant synaptic vesicle endocytosis mode during high neuronal activity and is sustained by glycogen synthase kinase 3β (GSK3β) activity. We reveal the GSK3β substrate PI4KIIα is essential for ADBE via its depletion in primary neuronal cultures. Kinase-dead PI4KIIα rescues ADBE in these neurons but not a phosphomimetic form mutated at the GSK3β site, Ser-47. Ser-47 phosphomimetic peptides inhibit ADBE in a dominant-negative manner, confirming that Ser-47 phosphorylation is essential for ADBE. Phosphomimetic PI4KIIα interacts with a specific cohort of presynaptic molecules, two of which, AGAP2 and CAMKV, are also essential for ADBE when depleted in neurons. Thus, PI4KIIα is a GSK3β-dependent interaction hub that silos essential ADBE molecules for liberation during neuronal activity.
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Affiliation(s)
- Eva-Maria Blumrich
- Centre for Discovery Brain Sciences, University of Edinburgh, Hugh Robson Building, George Square, Edinburgh, Scotland EH8 9XD, UK; Muir Maxwell Epilepsy Centre, University of Edinburgh, Hugh Robson Building, George Square, Edinburgh, Scotland EH8 9XD, UK; Simons Initiative for the Developing Brain, University of Edinburgh, Hugh Robson Building, George Square, Edinburgh, Scotland EH8 9XD, UK
| | - Jessica C Nicholson-Fish
- Centre for Discovery Brain Sciences, University of Edinburgh, Hugh Robson Building, George Square, Edinburgh, Scotland EH8 9XD, UK
| | - Marie Pronot
- Centre for Discovery Brain Sciences, University of Edinburgh, Hugh Robson Building, George Square, Edinburgh, Scotland EH8 9XD, UK; Muir Maxwell Epilepsy Centre, University of Edinburgh, Hugh Robson Building, George Square, Edinburgh, Scotland EH8 9XD, UK; Simons Initiative for the Developing Brain, University of Edinburgh, Hugh Robson Building, George Square, Edinburgh, Scotland EH8 9XD, UK
| | - Elizabeth C Davenport
- Centre for Discovery Brain Sciences, University of Edinburgh, Hugh Robson Building, George Square, Edinburgh, Scotland EH8 9XD, UK; Muir Maxwell Epilepsy Centre, University of Edinburgh, Hugh Robson Building, George Square, Edinburgh, Scotland EH8 9XD, UK; Simons Initiative for the Developing Brain, University of Edinburgh, Hugh Robson Building, George Square, Edinburgh, Scotland EH8 9XD, UK
| | - Dominic Kurian
- The Roslin Institute, University of Edinburgh, Easter Bush, Midlothian, Scotland EH25 9RG, UK
| | - Adam Cole
- Neurosignalling and Mood Disorders Group, The Garvan Institute of Medical Research, 384 Victoria Street, Darlinghurst, NSW 2010, Australia
| | - Karen J Smillie
- Centre for Discovery Brain Sciences, University of Edinburgh, Hugh Robson Building, George Square, Edinburgh, Scotland EH8 9XD, UK; Muir Maxwell Epilepsy Centre, University of Edinburgh, Hugh Robson Building, George Square, Edinburgh, Scotland EH8 9XD, UK.
| | - Michael A Cousin
- Centre for Discovery Brain Sciences, University of Edinburgh, Hugh Robson Building, George Square, Edinburgh, Scotland EH8 9XD, UK; Muir Maxwell Epilepsy Centre, University of Edinburgh, Hugh Robson Building, George Square, Edinburgh, Scotland EH8 9XD, UK; Simons Initiative for the Developing Brain, University of Edinburgh, Hugh Robson Building, George Square, Edinburgh, Scotland EH8 9XD, UK.
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3
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Higgs VE, Das RM. Establishing neuronal polarity: microtubule regulation during neurite initiation. OXFORD OPEN NEUROSCIENCE 2022; 1:kvac007. [PMID: 38596701 PMCID: PMC10913830 DOI: 10.1093/oons/kvac007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/14/2022] [Revised: 04/25/2022] [Accepted: 05/02/2022] [Indexed: 04/11/2024]
Abstract
The initiation of nascent projections, or neurites, from the neuronal cell body is the first stage in the formation of axons and dendrites, and thus a critical step in the establishment of neuronal architecture and nervous system development. Neurite formation relies on the polarized remodelling of microtubules, which dynamically direct and reinforce cell shape, and provide tracks for cargo transport and force generation. Within neurons, microtubule behaviour and structure are tightly controlled by an array of regulatory factors. Although microtubule regulation in the later stages of axon development is relatively well understood, how microtubules are regulated during neurite initiation is rarely examined. Here, we discuss how factors that direct microtubule growth, remodelling, stability and positioning influence neurite formation. In addition, we consider microtubule organization by the centrosome and modulation by the actin and intermediate filament networks to provide an up-to-date picture of this vital stage in neuronal development.
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Affiliation(s)
- Victoria E Higgs
- Division of Molecular and Cellular Function, Faculty of Biology, Medicine and Health, University of Manchester, Oxford Road, Manchester M13 9PT, UK
| | - Raman M Das
- Division of Molecular and Cellular Function, Faculty of Biology, Medicine and Health, University of Manchester, Oxford Road, Manchester M13 9PT, UK
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4
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Soliman A, Bakota L, Brandt R. Microtubule-modulating Agents in the Fight Against Neurodegeneration: Will it ever Work? Curr Neuropharmacol 2022; 20:782-798. [PMID: 34852744 PMCID: PMC9878958 DOI: 10.2174/1570159x19666211201101020] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2021] [Revised: 11/15/2021] [Accepted: 11/15/2021] [Indexed: 11/22/2022] Open
Abstract
The microtubule skeleton plays an essential role in nerve cells as the most important structural determinant of morphology and as a highway for axonal transport processes. Many neurodegenerative diseases are characterized by changes in the structure and organization of microtubules and microtubule-regulating proteins such as the microtubule-associated protein tau, which exhibits characteristic changes in a whole class of diseases collectively referred to as tauopathies. Changes in the dynamics of microtubules appear to occur early under neurodegenerative conditions and are also likely to contribute to age-related dysfunction of neurons. Thus, modulating microtubule dynamics and correcting impaired microtubule stability can be a useful neuroprotective strategy to counteract the disruption of the microtubule system in disease and aging. In this article, we review current microtubule- directed approaches for the treatment of neurodegenerative diseases with microtubules as a drug target, tau as a drug target, and post-translational modifications as potential modifiers of the microtubule system. We discuss limitations of the approaches that can be traced back to the rather unspecific mechanism of action, which causes undesirable side effects in non-neuronal cell types or which are due to the disruption of non-microtubule-related interactions. We also develop some thoughts on how the specificity of the approaches can be improved and what further targets could be used for modulating substances.
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Affiliation(s)
- Ahmed Soliman
- Department of Neurobiology, Osnabrück University, Osnabrück, Germany
| | - Lidia Bakota
- Department of Neurobiology, Osnabrück University, Osnabrück, Germany
| | - Roland Brandt
- Department of Neurobiology, Osnabrück University, Osnabrück, Germany;,Center for Cellular Nanoanalytics, Osnabrück University, Osnabrück, Germany;,Institute of Cognitive Science, Osnabrück University, Osnabrück, Germany,Address correspondence to this author at the Department of Neurobiology, Osnabrück University, Osnabrück, Germany; Tel: +49 541 969 2338; E-mail:
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5
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Foster HE, Ventura Santos C, Carter AP. A cryo-ET survey of microtubules and intracellular compartments in mammalian axons. J Cell Biol 2022; 221:e202103154. [PMID: 34878519 PMCID: PMC7612188 DOI: 10.1083/jcb.202103154] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2021] [Revised: 09/28/2021] [Accepted: 11/16/2021] [Indexed: 12/16/2022] Open
Abstract
The neuronal axon is packed with cytoskeletal filaments, membranes, and organelles, many of which move between the cell body and axon tip. Here, we used cryo-electron tomography to survey the internal components of mammalian sensory axons. We determined the polarity of the axonal microtubules (MTs) by combining subtomogram classification and visual inspection, finding MT plus and minus ends are structurally similar. Subtomogram averaging of globular densities in the MT lumen suggests they have a defined structure, which is surprising given they likely contain the disordered protein MAP6. We found the endoplasmic reticulum in axons is tethered to MTs through multiple short linkers. We surveyed membrane-bound cargos and describe unexpected internal features such as granules and broken membranes. In addition, we detected proteinaceous compartments, including numerous virus-like capsid particles. Our observations outline novel features of axonal cargos and MTs, providing a platform for identification of their constituents.
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6
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Meneses Iack P, Rayêe D, Lent R, Ribeiro-Resende VT, Garcez PP. Microcephaly gene Cenpj regulates axonal growth in cortical neurons through microtubule destabilization. J Neurochem 2021; 161:320-334. [PMID: 34940974 DOI: 10.1111/jnc.15568] [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: 04/16/2021] [Revised: 11/25/2021] [Accepted: 12/12/2021] [Indexed: 11/30/2022]
Abstract
Neocortex development comprises of a complex series of time- and space-specific processes to generate the typical interconnected six-layered architecture of adult mammals. Axon growth is required for the proper establishment of cortical circuits. Malformations in axonal growth and pathfinding might lead to severe neuropathologies, such as the Corpus Callosum dysgenesis. Cenpj, a microcephaly gene, encodes a scaffold protein that regulates centrosome biogenesis and microtubule stabilization. During cortical development, Cenpj regulates progenitor division and neuronal migration during corticogenesis. Since microtubule stabilization is crucial for axon extension, we investigated the role of Cenpj in axon extension during cortical development in a mouse model. Using performed loss- and gain-of-function assays ex vivo and in utero, we quantified callosal axonal length, branching and growth cone size compared to controls. We observed that silencing Cenpj results in an increased axonal length. Ex vivo, we assessed the number of branches, the area of growth cones and the stability of microtubules. In silenced Cenpj axons, there were more branches, larger growth cone area and more stable microtubules. Rescue experiments confirmed that neurons present axonal length comparable to controls. Here we propose that Cenpj regulates axon growth by destabilizing microtubules during cortical development. Finally, our findings suggest that Cenpj might be a novel target for axonal regeneration.
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Affiliation(s)
- Pamela Meneses Iack
- Universidade Federal do Rio de Janeiro, Instituto de Ciências Biomédicas, Laboratório de Neuroplasticidade, Centro de Ciências da Saúde Bloco F, Cidade Universitária, 21949-900, Rio de Janeiro, RJ, Brazil.,Universidade Federal do Rio de Janeiro, Instituto de Biofísica Carlos Chagas Filho, Laboratório de Neuroquímica, Centro de Ciências da Saúde, Bloco C, Cidade Universitária, 21949-900, Rio de Janeiro, RJ, Brazil
| | - Danielle Rayêe
- Universidade Federal do Rio de Janeiro, Instituto de Ciências Biomédicas, Laboratório de Neuroplasticidade, Centro de Ciências da Saúde Bloco F, Cidade Universitária, 21949-900, Rio de Janeiro, RJ, Brazil.,Department of Ophthalmology and Visual Sciences, Albert Einstein College of Medicine, NY, USA
| | - Roberto Lent
- Universidade Federal do Rio de Janeiro, Instituto de Ciências Biomédicas, Laboratório de Neuroplasticidade, Centro de Ciências da Saúde Bloco F, Cidade Universitária, 21949-900, Rio de Janeiro, RJ, Brazil.,D'Or Institute for Research and Education, Rio de Janeiro, RJ, Brazil
| | - Victor Túlio Ribeiro-Resende
- Universidade Federal do Rio de Janeiro, Instituto de Biofísica Carlos Chagas Filho, Laboratório de Neuroquímica, Centro de Ciências da Saúde, Bloco C, Cidade Universitária, 21949-900, Rio de Janeiro, RJ, Brazil.,Núcleo Multidisciplinar de Pesquisa em Biologia (Numpex-Bio), Universidade Federal do Rio de Janeiro, Campus de Duque de Caxias Geraldo Guerra Cidade, Duque de Caxias, RJ, 25255-030, Brazil
| | - Patrícia P Garcez
- Universidade Federal do Rio de Janeiro, Instituto de Ciências Biomédicas, Laboratório de Neuroplasticidade, Centro de Ciências da Saúde Bloco F, Cidade Universitária, 21949-900, Rio de Janeiro, RJ, Brazil
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7
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Boulan B, Ravanello C, Peyrel A, Bosc C, Delphin C, Appaix F, Denarier E, Kraut A, Jacquier-Sarlin M, Fournier A, Andrieux A, Gory-Fauré S, Deloulme JC. CRMP4-mediated fornix development involves Semaphorin-3E signaling pathway. eLife 2021; 10:e70361. [PMID: 34860155 PMCID: PMC8683083 DOI: 10.7554/elife.70361] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2021] [Accepted: 12/02/2021] [Indexed: 12/25/2022] Open
Abstract
Neurodevelopmental axonal pathfinding plays a central role in correct brain wiring and subsequent cognitive abilities. Within the growth cone, various intracellular effectors transduce axonal guidance signals by remodeling the cytoskeleton. Semaphorin-3E (Sema3E) is a guidance cue implicated in development of the fornix, a neuronal tract connecting the hippocampus to the hypothalamus. Microtubule-associated protein 6 (MAP6) has been shown to be involved in the Sema3E growth-promoting signaling pathway. In this study, we identified the collapsin response mediator protein 4 (CRMP4) as a MAP6 partner and a crucial effector in Sema3E growth-promoting activity. CRMP4-KO mice displayed abnormal fornix development reminiscent of that observed in Sema3E-KO mice. CRMP4 was shown to interact with the Sema3E tripartite receptor complex within detergent-resistant membrane (DRM) domains, and DRM domain integrity was required to transduce Sema3E signaling through the Akt/GSK3 pathway. Finally, we showed that the cytoskeleton-binding domain of CRMP4 is required for Sema3E's growth-promoting activity, suggesting that CRMP4 plays a role at the interface between Sema3E receptors, located in DRM domains, and the cytoskeleton network. As the fornix is affected in many psychiatric diseases, such as schizophrenia, our results provide new insights to better understand the neurodevelopmental components of these diseases.
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Affiliation(s)
- Benoît Boulan
- Univ. Grenoble Alpes, Inserm, U1216, CEA, Grenoble Institut NeurosciencesGrenobleFrance
| | - Charlotte Ravanello
- Univ. Grenoble Alpes, Inserm, U1216, CEA, Grenoble Institut NeurosciencesGrenobleFrance
| | - Amandine Peyrel
- Univ. Grenoble Alpes, Inserm, U1216, CEA, Grenoble Institut NeurosciencesGrenobleFrance
| | - Christophe Bosc
- Univ. Grenoble Alpes, Inserm, U1216, CEA, Grenoble Institut NeurosciencesGrenobleFrance
| | - Christian Delphin
- Univ. Grenoble Alpes, Inserm, U1216, CEA, Grenoble Institut NeurosciencesGrenobleFrance
| | - Florence Appaix
- Univ. Grenoble Alpes, Inserm, U1216, CEA, Grenoble Institut NeurosciencesGrenobleFrance
| | - Eric Denarier
- Univ. Grenoble Alpes, Inserm, U1216, CEA, Grenoble Institut NeurosciencesGrenobleFrance
| | - Alexandra Kraut
- Univ. Grenoble Alpes, Inserm, CEA, UMR BioSanté U1292, CNRS, CEAGrenobleFrance
| | | | - Alyson Fournier
- Department of Neurology and Neurosurgery, Montréal Neurological Institute, McGill UniversityMontréalCanada
| | - Annie Andrieux
- Univ. Grenoble Alpes, Inserm, U1216, CEA, Grenoble Institut NeurosciencesGrenobleFrance
| | - Sylvie Gory-Fauré
- Univ. Grenoble Alpes, Inserm, U1216, CEA, Grenoble Institut NeurosciencesGrenobleFrance
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8
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Cuveillier C, Boulan B, Ravanello C, Denarier E, Deloulme JC, Gory-Fauré S, Delphin C, Bosc C, Arnal I, Andrieux A. Beyond Neuronal Microtubule Stabilization: MAP6 and CRMPS, Two Converging Stories. Front Mol Neurosci 2021; 14:665693. [PMID: 34025352 PMCID: PMC8131560 DOI: 10.3389/fnmol.2021.665693] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2021] [Accepted: 04/09/2021] [Indexed: 12/21/2022] Open
Abstract
The development and function of the central nervous system rely on the microtubule (MT) and actin cytoskeletons and their respective effectors. Although the structural role of the cytoskeleton has long been acknowledged in neuronal morphology and activity, it was recently recognized to play the role of a signaling platform. Following this recognition, research into Microtubule Associated Proteins (MAPs) diversified. Indeed, historically, structural MAPs—including MAP1B, MAP2, Tau, and MAP6 (also known as STOP);—were identified and described as MT-binding and -stabilizing proteins. Extensive data obtained over the last 20 years indicated that these structural MAPs could also contribute to a variety of other molecular roles. Among multi-role MAPs, MAP6 provides a striking example illustrating the diverse molecular and cellular properties of MAPs and showing how their functional versatility contributes to the central nervous system. In this review, in addition to MAP6’s effect on microtubules, we describe its impact on the actin cytoskeleton, on neuroreceptor homeostasis, and its involvement in signaling pathways governing neuron development and maturation. We also discuss its roles in synaptic plasticity, brain connectivity, and cognitive abilities, as well as the potential relationships between the integrated brain functions of MAP6 and its molecular activities. In parallel, the Collapsin Response Mediator Proteins (CRMPs) are presented as examples of how other proteins, not initially identified as MAPs, fall into the broader MAP family. These proteins bind MTs as well as exhibiting molecular and cellular properties very similar to MAP6. Finally, we briefly summarize the multiple similarities between other classical structural MAPs and MAP6 or CRMPs.In summary, this review revisits the molecular properties and the cellular and neuronal roles of the classical MAPs, broadening our definition of what constitutes a MAP.
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9
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Parato J, Bartolini F. The microtubule cytoskeleton at the synapse. Neurosci Lett 2021; 753:135850. [PMID: 33775740 DOI: 10.1016/j.neulet.2021.135850] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2021] [Revised: 03/19/2021] [Accepted: 03/22/2021] [Indexed: 12/13/2022]
Abstract
In neurons, microtubules (MTs) provide routes for transport throughout the cell and structural support for dendrites and axons. Both stable and dynamic MTs are necessary for normal neuronal functions. Research in the last two decades has demonstrated that MTs play additional roles in synaptic structure and function in both pre- and postsynaptic elements. Here, we review current knowledge of the functions that MTs perform in excitatory and inhibitory synapses, as well as in the neuromuscular junction and other specialized synapses, and discuss the implications that this knowledge may have in neurological disease.
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Affiliation(s)
- Julie Parato
- Columbia University Medical Center, Department of Pathology & Cell Biology, 630 West 168(th)Street, P&S 15-421, NY, NY, 10032, United States; SUNY Empire State College, Department of Natural Sciences, 177 Livingston Street, Brooklyn, NY, 11201, United States
| | - Francesca Bartolini
- Columbia University Medical Center, Department of Pathology & Cell Biology, 630 West 168(th)Street, P&S 15-421, NY, NY, 10032, United States.
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10
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Regulation of actin dynamics in dendritic spines: Nanostructure, molecular mobility, and signaling mechanisms. Mol Cell Neurosci 2020; 109:103564. [DOI: 10.1016/j.mcn.2020.103564] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2020] [Accepted: 10/04/2020] [Indexed: 12/16/2022] Open
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11
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Twelvetrees AE. The lifecycle of the neuronal microtubule transport machinery. Semin Cell Dev Biol 2020; 107:74-81. [DOI: 10.1016/j.semcdb.2020.02.008] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2020] [Revised: 02/24/2020] [Accepted: 02/25/2020] [Indexed: 01/08/2023]
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12
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Ma L, Song J, Sun X, Ding W, Fan K, Qi M, Xu Y, Zhang W. Role of microtubule-associated protein 6 glycosylated with Gal-(β-1,3)-GalNAc in Parkinson's disease. Aging (Albany NY) 2020; 11:4597-4610. [PMID: 31289257 PMCID: PMC6660046 DOI: 10.18632/aging.102072] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2019] [Accepted: 06/28/2019] [Indexed: 12/13/2022]
Abstract
Aberrant glycosylation of proteins has major implications for human diseases. To determine whether protein glycosylation contributes to the pathogenesis of Parkinson’s disease (PD), a mouse model of PD was established by injection of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP). Induction of PD-like features was verified by assessing motor impairment and confirming reductions in biological markers, including dopamine, 5-hydroxytryptamine and tyrosine hydroxylase, as well as the aggregation of α-synuclein. Altered glycosylation was detected using biotinylated agaracus bisporus lectin, which specifically binds exposed Gal-(β-1,3)-GalNAc linked to glycoproteins. Subsequent lectin affinity chromatography coupled with mass spectrometry revealed enhanced glycosylation of microtubule-associated protein 6 (MAP6) in PD mice as compared to healthy controls. In situ dual co-immunofluorescence analysis and immunoblotting confirmed that MAP6 is glycosylated with Gal-(β-1,3)-GalNAc oligosaccharides, which in turn alters the distribution and structure of MAP6 complexes within neurons. This is the first study to described MAP6 as a glycoprotein containing Gal-(β-1,3)-GalNAc oligosaccharides and to show that hyperglycosylation of MAP6 is strongly associated with the pathogenesis of PD. These findings provide potentially valuable information for developing new therapeutic targets for the treatment of PD as well as reliably prognostic biomarkers.
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Affiliation(s)
- Li Ma
- Department of Epidemiology, Dalian Medical University, Dalian 116044, China
| | - Jiaxin Song
- Department of Epidemiology, Dalian Medical University, Dalian 116044, China
| | - Xueying Sun
- Department of Epidemiology, Dalian Medical University, Dalian 116044, China
| | - Wenyong Ding
- Biochemistry and Molecular Biology Department of College of Basic Medical Sciences, Dalian Medical University, Dalian 116044, China
| | - Kaiyang Fan
- Medical Administration Department, Affiliated Hospital of Jining Medical University, Jining 272000, China
| | - Minghua Qi
- Biochemistry and Molecular Biology Department of College of Basic Medical Sciences, Dalian Medical University, Dalian 116044, China
| | - Yuefei Xu
- Biochemistry and Molecular Biology Department of College of Basic Medical Sciences, Dalian Medical University, Dalian 116044, China
| | - Wenli Zhang
- Biochemistry and Molecular Biology Department of College of Basic Medical Sciences, Dalian Medical University, Dalian 116044, China
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13
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Cuveillier C, Delaroche J, Seggio M, Gory-Fauré S, Bosc C, Denarier E, Bacia M, Schoehn G, Mohrbach H, Kulić I, Andrieux A, Arnal I, Delphin C. MAP6 is an intraluminal protein that induces neuronal microtubules to coil. SCIENCE ADVANCES 2020; 6:eaaz4344. [PMID: 32270043 PMCID: PMC7112752 DOI: 10.1126/sciadv.aaz4344] [Citation(s) in RCA: 43] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/09/2019] [Accepted: 01/09/2020] [Indexed: 06/01/2023]
Abstract
Neuronal activities depend heavily on microtubules, which shape neuronal processes and transport myriad molecules within them. Although constantly remodeled through growth and shrinkage events, neuronal microtubules must be sufficiently stable to maintain nervous system wiring. This stability is somehow maintained by various microtubule-associated proteins (MAPs), but little is known about how these proteins work. Here, we show that MAP6, previously known to confer cold stability to microtubules, promotes growth. More unexpectedly, MAP6 localizes in the lumen of microtubules, induces the microtubules to coil into a left-handed helix, and forms apertures in the lattice, likely to relieve mechanical stress. These features have not been seen in microtubules before and could play roles in maintaining axonal width or providing flexibility in the face of compressive forces during development.
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Affiliation(s)
- Camille Cuveillier
- Univ. Grenoble Alpes, Inserm U1216, CEA, CNRS, Grenoble Institut Neurosciences, GIN, 38000 Grenoble, France
| | - Julie Delaroche
- Univ. Grenoble Alpes, Inserm U1216, CEA, CNRS, Grenoble Institut Neurosciences, GIN, 38000 Grenoble, France
| | - Maxime Seggio
- Univ. Grenoble Alpes, Inserm U1216, CEA, CNRS, Grenoble Institut Neurosciences, GIN, 38000 Grenoble, France
| | - Sylvie Gory-Fauré
- Univ. Grenoble Alpes, Inserm U1216, CEA, CNRS, Grenoble Institut Neurosciences, GIN, 38000 Grenoble, France
| | - Christophe Bosc
- Univ. Grenoble Alpes, Inserm U1216, CEA, CNRS, Grenoble Institut Neurosciences, GIN, 38000 Grenoble, France
| | - Eric Denarier
- Univ. Grenoble Alpes, Inserm U1216, CEA, CNRS, Grenoble Institut Neurosciences, GIN, 38000 Grenoble, France
| | - Maria Bacia
- Univ. Grenoble Alpes, CNRS, CEA, Institut for Structural Biology (IBS), 38000 Grenoble, France
| | - Guy Schoehn
- Univ. Grenoble Alpes, CNRS, CEA, Institut for Structural Biology (IBS), 38000 Grenoble, France
| | - Hervé Mohrbach
- Laboratoire de Chimie et Physique Théorique, UMR 7019, Université de Lorraine
| | - Igor Kulić
- Institut Charles Sandron, CNRS-UdS, 67034 Strasbourg, France
| | - Annie Andrieux
- Univ. Grenoble Alpes, Inserm U1216, CEA, CNRS, Grenoble Institut Neurosciences, GIN, 38000 Grenoble, France
| | - Isabelle Arnal
- Univ. Grenoble Alpes, Inserm U1216, CEA, CNRS, Grenoble Institut Neurosciences, GIN, 38000 Grenoble, France
| | - Christian Delphin
- Univ. Grenoble Alpes, Inserm U1216, CEA, CNRS, Grenoble Institut Neurosciences, GIN, 38000 Grenoble, France
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14
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O V SS, Palaparthi S, Pidaparti R. Mimicking Sub-Structures Self-Organization in Microtubules. Biomimetics (Basel) 2019; 4:biomimetics4040071. [PMID: 31635308 PMCID: PMC6963431 DOI: 10.3390/biomimetics4040071] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2019] [Revised: 09/19/2019] [Accepted: 10/15/2019] [Indexed: 01/25/2023] Open
Abstract
Microtubules (MTs) are highly dynamic polymers distributed in the cytoplasm of a biological cell. Alpha and beta globular proteins constituting the heterodimer building blocks combine to form these tubules through polymerization, controlled by the concentration of Guanosine-triphosphate (GTPs) and other Microtubule Associated Proteins (MAPs). MTs play a crucial role in many intracellular processes, predominantly in mitosis, organelle transport and cell locomotion. Current research in this area is focused on understanding the exclusive behaviors of self-organization and their association with different MAPs through organized laboratory experiments. However, the intriguing intelligence behind these tiny machines resulting in complex self-organizing structures is mostly unexplored. In this study, we propose a novel swarm engineering framework in modeling rules for these systems, by combining the principles of design with swarm intelligence. The proposed framework was simulated on a game engine and these simulations demonstrated self-organization of rings and protofilaments in MTs. Analytics from these simulations assisted in understanding the influence of GTPs on protofilament formation. Also, results showed that the population density of GTPs rather than their bonding probabilities played a crucial role in polymerization in forming microtubule substructures.
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Affiliation(s)
- Sanjay Sarma O V
- College of Engineering, University of Georgia, Athens, GA 30602, USA.
| | - Sruthi Palaparthi
- Department of Computer Science, University of Georgia, Athens, GA 30602, USA.
| | - Ramana Pidaparti
- College of Engineering, University of Georgia, Athens, GA 30602, USA.
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15
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Li T, Tang H, Zhu J, Zhang JH. The finer scale of consciousness: quantum theory. ANNALS OF TRANSLATIONAL MEDICINE 2019; 7:585. [PMID: 31807566 DOI: 10.21037/atm.2019.09.09] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Consciousness is a multidisciplinary problem that has puzzled all human beings since the origin of human life. Being defined in various pointcuts by philosophers, biologists, physicists, and neuroscientists, the definitive explanation of consciousness is still suspending. The nature of consciousness has taken great evolution by centering on the behavioral and neuronal correlates of perception and cognition, for example, the theory of Neural Correlates of Consciousness, the Global Workspace Theory, the Integrated Information Theory. While tremendous progress has been achieved, they are not enough if we are to understand even basic facts-how and where does the consciousness emerge. The Quantum mechanics, a thriving branch of physics, has an inseparable relationship with consciousness (e.g., observer effect) since Planck created this subject and its derived quantum consciousness theory can perfectly fill this gap. In this review, we briefly introduce some consciousness hypotheses derived from quantum mechanics and focus on the framework of orchestrated objective reduction (Orch-OR), including its principal points and practicality.
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Affiliation(s)
- Tianwen Li
- Department of Neurosurgery, Fudan University Huashan Hospital, National Key Laboratory of Medical Neurobiology, the Institutes of Brain Science and the Collaborative Innovation Center for Brain Science, Shanghai Medical College, Fudan University, Shanghai 200040, China
| | - Hailiang Tang
- Department of Neurosurgery, Fudan University Huashan Hospital, National Key Laboratory of Medical Neurobiology, the Institutes of Brain Science and the Collaborative Innovation Center for Brain Science, Shanghai Medical College, Fudan University, Shanghai 200040, China
| | - Jianhong Zhu
- Department of Neurosurgery, Fudan University Huashan Hospital, National Key Laboratory of Medical Neurobiology, the Institutes of Brain Science and the Collaborative Innovation Center for Brain Science, Shanghai Medical College, Fudan University, Shanghai 200040, China
| | - John H Zhang
- Center for Neuroscience Research, Loma Linda University School of Medicine, Loma Linda, CA, USA
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16
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Sébastien M, Giannesini B, Aubin P, Brocard J, Chivet M, Pietrangelo L, Boncompagni S, Bosc C, Brocard J, Rendu J, Gory-Fauré S, Andrieux A, Fourest-Lieuvin A, Fauré J, Marty I. Deletion of the microtubule-associated protein 6 (MAP6) results in skeletal muscle dysfunction. Skelet Muscle 2018; 8:30. [PMID: 30231928 PMCID: PMC6147105 DOI: 10.1186/s13395-018-0176-8] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2018] [Accepted: 09/12/2018] [Indexed: 01/23/2023] Open
Abstract
Background The skeletal muscle fiber has a specific and precise intracellular organization which is at the basis of an efficient muscle contraction. Microtubules are long known to play a major role in the function and organization of many cells, but in skeletal muscle, the contribution of the microtubule cytoskeleton to the efficiency of contraction has only recently been studied. The microtubule network is dynamic and is regulated by many microtubule-associated proteins (MAPs). In the present study, the role of the MAP6 protein in skeletal muscle organization and function has been studied using the MAP6 knockout mouse line. Methods The presence of MAP6 transcripts and proteins was shown in mouse muscle homogenates and primary culture using RT-PCR and western blot. The in vivo evaluation of muscle force of MAP6 knockout (KO) mice was performed on anesthetized animals using electrostimulation coupled to mechanical measurement and multimodal magnetic resonance. The impact of MAP6 deletion on microtubule organization and intracellular structures was studied using immunofluorescent labeling and electron microscopy, and on calcium release for muscle contraction using Fluo-4 calcium imaging on cultured myotubes. Statistical analysis was performed using Student’s t test or the Mann-Whitney test. Results We demonstrate the presence of MAP6 transcripts and proteins in skeletal muscle. Deletion of MAP6 results in a large number of muscle modifications: muscle weakness associated with slight muscle atrophy, alterations of microtubule network and sarcoplasmic reticulum organization, and reduction in calcium release. Conclusion Altogether, our results demonstrate that MAP6 is involved in skeletal muscle function. Its deletion results in alterations in skeletal muscle contraction which contribute to the global deleterious phenotype of the MAP6 KO mice. As MAP6 KO mouse line is a model for schizophrenia, our work points to a possible muscle weakness associated to some forms of schizophrenia. Electronic supplementary material The online version of this article (10.1186/s13395-018-0176-8) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Muriel Sébastien
- INSERM 1216, Grenoble Institute of Neurosciences, F-38000, Grenoble, France.,University Grenoble Alpes, F-38000, Grenoble, France
| | | | - Perrine Aubin
- INSERM 1216, Grenoble Institute of Neurosciences, F-38000, Grenoble, France.,University Grenoble Alpes, F-38000, Grenoble, France
| | - Julie Brocard
- INSERM 1216, Grenoble Institute of Neurosciences, F-38000, Grenoble, France.,University Grenoble Alpes, F-38000, Grenoble, France
| | - Mathilde Chivet
- INSERM 1216, Grenoble Institute of Neurosciences, F-38000, Grenoble, France.,University Grenoble Alpes, F-38000, Grenoble, France
| | - Laura Pietrangelo
- CeSI-Met & DNICS, University G. d' Annunzio of Chieti, I-66100, Chieti, Italy
| | - Simona Boncompagni
- CeSI-Met & DNICS, University G. d' Annunzio of Chieti, I-66100, Chieti, Italy
| | - Christophe Bosc
- INSERM 1216, Grenoble Institute of Neurosciences, F-38000, Grenoble, France.,University Grenoble Alpes, F-38000, Grenoble, France
| | - Jacques Brocard
- INSERM 1216, Grenoble Institute of Neurosciences, F-38000, Grenoble, France.,University Grenoble Alpes, F-38000, Grenoble, France
| | - John Rendu
- INSERM 1216, Grenoble Institute of Neurosciences, F-38000, Grenoble, France.,University Grenoble Alpes, F-38000, Grenoble, France.,CHU Grenoble, Biochimie et Génétique Moléculaire, F-38000, Grenoble, France
| | - Sylvie Gory-Fauré
- INSERM 1216, Grenoble Institute of Neurosciences, F-38000, Grenoble, France.,University Grenoble Alpes, F-38000, Grenoble, France
| | - Annie Andrieux
- INSERM 1216, Grenoble Institute of Neurosciences, F-38000, Grenoble, France.,University Grenoble Alpes, F-38000, Grenoble, France.,CEA-Grenoble, BIG, F-38000, Grenoble, France
| | - Anne Fourest-Lieuvin
- INSERM 1216, Grenoble Institute of Neurosciences, F-38000, Grenoble, France.,University Grenoble Alpes, F-38000, Grenoble, France.,CEA-Grenoble, BIG, F-38000, Grenoble, France
| | - Julien Fauré
- INSERM 1216, Grenoble Institute of Neurosciences, F-38000, Grenoble, France.,University Grenoble Alpes, F-38000, Grenoble, France.,CHU Grenoble, Biochimie et Génétique Moléculaire, F-38000, Grenoble, France
| | - Isabelle Marty
- INSERM 1216, Grenoble Institute of Neurosciences, F-38000, Grenoble, France. .,University Grenoble Alpes, F-38000, Grenoble, France. .,GIN- Inserm U1216 - Bat EJ Safra, Chemin Fortuné Ferrini, 38700, La Tronche, France.
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17
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Ou J, Ball JM, Luan Y, Zhao T, Miyagishima KJ, Xu Y, Zhou H, Chen J, Merriman DK, Xie Z, Mallon BS, Li W. iPSCs from a Hibernator Provide a Platform for Studying Cold Adaptation and Its Potential Medical Applications. Cell 2018; 173:851-863.e16. [PMID: 29576452 DOI: 10.1016/j.cell.2018.03.010] [Citation(s) in RCA: 68] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2017] [Revised: 12/12/2017] [Accepted: 03/02/2018] [Indexed: 12/22/2022]
Abstract
Hibernating mammals survive hypothermia (<10°C) without injury, a remarkable feat of cellular preservation that bears significance for potential medical applications. However, mechanisms imparting cold resistance, such as cytoskeleton stability, remain elusive. Using the first iPSC line from a hibernating mammal (13-lined ground squirrel), we uncovered cellular pathways critical for cold tolerance. Comparison between human and ground squirrel iPSC-derived neurons revealed differential mitochondrial and protein quality control responses to cold. In human iPSC-neurons, cold triggered mitochondrial stress, resulting in reactive oxygen species overproduction and lysosomal membrane permeabilization, contributing to microtubule destruction. Manipulations of these pathways endowed microtubule cold stability upon human iPSC-neurons and rat (a non-hibernator) retina, preserving its light responsiveness after prolonged cold exposure. Furthermore, these treatments significantly improved microtubule integrity in cold-stored kidneys, demonstrating the potential for prolonging shelf-life of organ transplants. Thus, ground squirrel iPSCs offer a unique platform for bringing cold-adaptive strategies from hibernators to humans in clinical applications. VIDEO ABSTRACT.
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Affiliation(s)
- Jingxing Ou
- Retinal Neurophysiology Section, National Eye Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - John M Ball
- Retinal Neurophysiology Section, National Eye Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Yizhao Luan
- State Key Laboratory of Ophthalmology, Guangdong Provincial Key Lab of Ophthalmology and Visual Science, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou 510060, China; School of Life Sciences, Sun Yat-sen University, Guangzhou 510275, China
| | - Tantai Zhao
- Retinal Neurophysiology Section, National Eye Institute, National Institutes of Health, Bethesda, MD 20892, USA; Department of Ophthalmology, The Second Xiang-Ya Hospital, Central South University, Changsha 410011, China
| | - Kiyoharu J Miyagishima
- Retinal Neurophysiology Section, National Eye Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Yufeng Xu
- Retinal Neurophysiology Section, National Eye Institute, National Institutes of Health, Bethesda, MD 20892, USA; Department of Ophthalmology, The Second Affiliated Hospital of Zhejiang University, College of Medicine, Hangzhou 310009, China
| | - Huizhi Zhou
- Trans-NIH Center for Human Immunology, Autoimmunity, and Inflammation, National Institutes of Health, Bethesda, MD 20892, USA
| | - Jinguo Chen
- Trans-NIH Center for Human Immunology, Autoimmunity, and Inflammation, National Institutes of Health, Bethesda, MD 20892, USA
| | - Dana K Merriman
- Department of Biology, University of Wisconsin, Oshkosh, WI 54901, USA
| | - Zhi Xie
- State Key Laboratory of Ophthalmology, Guangdong Provincial Key Lab of Ophthalmology and Visual Science, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou 510060, China
| | - Barbara S Mallon
- NIH Stem Cell Unit, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD 20892, USA
| | - Wei Li
- Retinal Neurophysiology Section, National Eye Institute, National Institutes of Health, Bethesda, MD 20892, USA.
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18
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Brocard J, Dufour F, Gory-Fauré S, Arnoult C, Bosc C, Denarier E, Peris L, Saoudi Y, De Waard M, Andrieux A. MAP6 interacts with Tctex1 and Ca v 2.2/N-type calcium channels to regulate calcium signalling in neurons. Eur J Neurosci 2017; 46:2754-2767. [PMID: 29094416 PMCID: PMC5765474 DOI: 10.1111/ejn.13766] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2017] [Revised: 10/20/2017] [Accepted: 10/23/2017] [Indexed: 11/29/2022]
Abstract
MAP6 proteins were first described as microtubule‐stabilizing agents, whose properties were thought to be essential for neuronal development and maintenance of complex neuronal networks. However, deletion of all MAP6 isoforms in MAP6 KO mice does not lead to dramatic morphological aberrations of the brain but rather to alterations in multiple neurotransmissions and severe behavioural impairments. A search for protein partners of MAP6 proteins identified Tctex1 – a dynein light chain with multiple non‐microtubule‐related functions. The involvement of Tctex1 in calcium signalling led to investigate it in MAP6 KO neurons. In this study, we show that functional Cav2.2/N‐type calcium channels are deficient in MAP6 KO neurons, due to improper location. We also show that MAP6 proteins interact directly with both Tctex1 and the C‐terminus of Cav2.2/N‐type calcium channels. A balance of these two interactions seems to be crucial for MAP6 to modulate calcium signalling in neurons.
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Affiliation(s)
- Jacques Brocard
- U1216, INSERM, Grenoble, F-38000, France.,Grenoble Institute of Neuroscience, Université Grenoble Alpes, Grenoble, France
| | - Fabrice Dufour
- U1216, INSERM, Grenoble, F-38000, France.,Grenoble Institute of Neuroscience, Université Grenoble Alpes, Grenoble, France
| | - Sylvie Gory-Fauré
- U1216, INSERM, Grenoble, F-38000, France.,Grenoble Institute of Neuroscience, Université Grenoble Alpes, Grenoble, France
| | - Christophe Arnoult
- U1209, INSERM, Grenoble, France.,UMR 5309, CNRS, Grenoble, France.,Institute for Advanced Biosciences, Université Grenoble Alpes, Grenoble, France
| | - Christophe Bosc
- U1216, INSERM, Grenoble, F-38000, France.,Grenoble Institute of Neuroscience, Université Grenoble Alpes, Grenoble, France
| | - Eric Denarier
- U1216, INSERM, Grenoble, F-38000, France.,Grenoble Institute of Neuroscience, Université Grenoble Alpes, Grenoble, France.,CEA, BIG-GPC, Grenoble, France
| | - Leticia Peris
- U1216, INSERM, Grenoble, F-38000, France.,Grenoble Institute of Neuroscience, Université Grenoble Alpes, Grenoble, France
| | - Yasmina Saoudi
- U1216, INSERM, Grenoble, F-38000, France.,Grenoble Institute of Neuroscience, Université Grenoble Alpes, Grenoble, France
| | - Michel De Waard
- U1087, INSERM, Nantes, France.,UMR 6291, CNRS, Nantes, France.,Université Nantes, Nantes, France
| | - Annie Andrieux
- U1216, INSERM, Grenoble, F-38000, France.,Grenoble Institute of Neuroscience, Université Grenoble Alpes, Grenoble, France.,CEA, BIG-GPC, Grenoble, France
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19
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Establishing Neuronal Polarity with Environmental and Intrinsic Mechanisms. Neuron 2017; 96:638-650. [DOI: 10.1016/j.neuron.2017.10.021] [Citation(s) in RCA: 63] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2017] [Revised: 10/14/2017] [Accepted: 10/15/2017] [Indexed: 12/31/2022]
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20
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Dynamic Palmitoylation Targets MAP6 to the Axon to Promote Microtubule Stabilization during Neuronal Polarization. Neuron 2017; 94:809-825.e7. [PMID: 28521134 DOI: 10.1016/j.neuron.2017.04.042] [Citation(s) in RCA: 68] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2016] [Revised: 02/19/2017] [Accepted: 04/27/2017] [Indexed: 11/22/2022]
Abstract
Microtubule-associated proteins (MAPs) are main candidates to stabilize neuronal microtubules, playing an important role in establishing axon-dendrite polarity. However, how MAPs are selectively targeted to specific neuronal compartments remains poorly understood. Here, we show specific localization of microtubule-associated protein 6 (MAP6)/stable tubule-only polypeptide (STOP) throughout neuronal maturation and its role in axonal development. In unpolarized neurons, MAP6 is present at the Golgi complex and in secretory vesicles. As neurons mature, MAP6 is translocated to the proximal axon, where it binds and stabilizes microtubules. Further, we demonstrate that dynamic palmitoylation, mediated by the family of α/β Hydrolase domain-containing protein 17 (ABHD17A-C) depalmitoylating enzymes, controls shuttling of MAP6 between membranes and microtubules and is required for MAP6 retention in axons. We propose a model in which MAP6's palmitoylation mediates microtubule stabilization, allows efficient organelle trafficking, and controls axon maturation in vitro and in situ.
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21
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Gu Y, Jukkola P, Wang Q, Esparza T, Zhao Y, Brody D, Gu C. Polarity of varicosity initiation in central neuron mechanosensation. J Cell Biol 2017; 216:2179-2199. [PMID: 28606925 PMCID: PMC5496611 DOI: 10.1083/jcb.201606065] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2016] [Revised: 01/17/2017] [Accepted: 04/20/2017] [Indexed: 12/22/2022] Open
Abstract
Little is known about mechanical regulation of morphological and functional polarity of central neurons. In this study, we report that mechanical stress specifically induces varicosities in the axons but not the dendrites of central neurons by activating TRPV4, a Ca2+/Na+-permeable mechanosensitive channel. This process is unexpectedly rapid and reversible, consistent with the formation of axonal varicosities in vivo induced by mechanical impact in a mouse model of mild traumatic brain injury. In contrast, prolonged stimulation of glutamate receptors induces varicosities in dendrites but not in axons. We further show that axonal varicosities are induced by persistent Ca2+ increase, disassembled microtubules (MTs), and subsequently reversible disruption of axonal transport, and are regulated by stable tubulin-only polypeptide, an MT-associated protein. Finally, axonal varicosity initiation can trigger action potentials to antidromically propagate to the soma in retrograde signaling. Therefore, our study demonstrates a new feature of neuronal polarity: axons and dendrites preferentially respond to physical and chemical stresses, respectively.
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Affiliation(s)
- Yuanzheng Gu
- Department of Biological Chemistry and Pharmacology, The Ohio State University, Columbus, OH
| | - Peter Jukkola
- Biomedical Sciences Graduate Program, The Ohio State University, Columbus, OH
| | - Qian Wang
- Biomedical Engineering Department, The Ohio State University, Columbus, OH
| | - Thomas Esparza
- Department of Neurology, Washington University, St. Louis, MO
| | - Yi Zhao
- Biomedical Engineering Department, The Ohio State University, Columbus, OH
| | - David Brody
- Department of Neurology, Washington University, St. Louis, MO
| | - Chen Gu
- Department of Biological Chemistry and Pharmacology, The Ohio State University, Columbus, OH .,Biomedical Sciences Graduate Program, The Ohio State University, Columbus, OH
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22
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Penazzi L, Bakota L, Brandt R. Microtubule Dynamics in Neuronal Development, Plasticity, and Neurodegeneration. INTERNATIONAL REVIEW OF CELL AND MOLECULAR BIOLOGY 2015; 321:89-169. [PMID: 26811287 DOI: 10.1016/bs.ircmb.2015.09.004] [Citation(s) in RCA: 64] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Neurons are the basic information-processing units of the nervous system. In fulfilling their task, they establish a structural polarity with an axon that can be over a meter long and dendrites with a complex arbor, which can harbor ten-thousands of spines. Microtubules and their associated proteins play important roles during the development of neuronal morphology, the plasticity of neurons, and neurodegenerative processes. They are dynamic structures, which can quickly adapt to changes in the environment and establish a structural scaffold with high local variations in composition and stability. This review presents a comprehensive overview about the role of microtubules and their dynamic behavior during the formation and maturation of processes and spines in the healthy brain, during aging and under neurodegenerative conditions. The review ends with a discussion of microtubule-targeted therapies as a perspective for the supportive treatment of neurodegenerative disorders.
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Affiliation(s)
- Lorène Penazzi
- Department of Neurobiology, University of Osnabrück, Osnabrück, Germany
| | - Lidia Bakota
- Department of Neurobiology, University of Osnabrück, Osnabrück, Germany
| | - Roland Brandt
- Department of Neurobiology, University of Osnabrück, Osnabrück, Germany
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23
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Lemonidis K, Sanchez-Perez MC, Chamberlain LH. Identification of a Novel Sequence Motif Recognized by the Ankyrin Repeat Domain of zDHHC17/13 S-Acyltransferases. J Biol Chem 2015; 290:21939-50. [PMID: 26198635 PMCID: PMC4571948 DOI: 10.1074/jbc.m115.657668] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2015] [Revised: 07/20/2015] [Indexed: 11/06/2022] Open
Abstract
S-Acylation is a major post-translational modification affecting several cellular processes. It is particularly important for neuronal functions. This modification is catalyzed by a family of transmembrane S-acyltransferases that contain a conserved zinc finger DHHC (zDHHC) domain. Typically, eukaryote genomes encode for 7-24 distinct zDHHC enzymes, with two members also harboring an ankyrin repeat (AR) domain at their cytosolic N termini. The AR domain of zDHHC enzymes is predicted to engage in numerous interactions and facilitates both substrate recruitment and S-acylation-independent functions; however, the sequence/structural features recognized by this module remain unknown. The two mammalian AR-containing S-acyltransferases are the Golgi-localized zDHHC17 and zDHHC13, also known as Huntingtin-interacting proteins 14 and 14-like, respectively; they are highly expressed in brain, and their loss in mice leads to neuropathological deficits that are reminiscent of Huntington's disease. Here, we report that zDHHC17 and zDHHC13 recognize, via their AR domain, evolutionary conserved and closely related sequences of a [VIAP][VIT]XXQP consensus in SNAP25, SNAP23, cysteine string protein, Huntingtin, cytoplasmic linker protein 3, and microtubule-associated protein 6. This novel AR-binding sequence motif is found in regions predicted to be unstructured and is present in a number of zDHHC17 substrates and zDHHC17/13-interacting S-acylated proteins. This is the first study to identify a motif recognized by AR-containing zDHHCs.
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Affiliation(s)
- Kimon Lemonidis
- From the Strathclyde Institute of Pharmacy and Biomedical Sciences, Univesity of Strathclyde, Glasgow G4 0RE, United Kingdom
| | - Maria C Sanchez-Perez
- From the Strathclyde Institute of Pharmacy and Biomedical Sciences, Univesity of Strathclyde, Glasgow G4 0RE, United Kingdom
| | - Luke H Chamberlain
- From the Strathclyde Institute of Pharmacy and Biomedical Sciences, Univesity of Strathclyde, Glasgow G4 0RE, United Kingdom
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24
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25
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Deloulme JC, Gory-Fauré S, Mauconduit F, Chauvet S, Jonckheere J, Boulan B, Mire E, Xue J, Jany M, Maucler C, Deparis AA, Montigon O, Daoust A, Barbier EL, Bosc C, Deglon N, Brocard J, Denarier E, Le Brun I, Pernet-Gallay K, Vilgrain I, Robinson PJ, Lahrech H, Mann F, Andrieux A. Microtubule-associated protein 6 mediates neuronal connectivity through Semaphorin 3E-dependent signalling for axonal growth. Nat Commun 2015; 6:7246. [PMID: 26037503 PMCID: PMC4468860 DOI: 10.1038/ncomms8246] [Citation(s) in RCA: 49] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2014] [Accepted: 04/22/2015] [Indexed: 01/07/2023] Open
Abstract
Structural microtubule associated proteins (MAPs) stabilize microtubules, a property that was thought to be essential for development, maintenance and function of neuronal circuits. However, deletion of the structural MAPs in mice does not lead to major neurodevelopment defects. Here we demonstrate a role for MAP6 in brain wiring that is independent of microtubule binding. We find that MAP6 deletion disrupts brain connectivity and is associated with a lack of post-commissural fornix fibres. MAP6 contributes to fornix development by regulating axonal elongation induced by Semaphorin 3E. We show that MAP6 acts downstream of receptor activation through a mechanism that requires a proline-rich domain distinct from its microtubule-stabilizing domains. We also show that MAP6 directly binds to SH3 domain proteins known to be involved in neurite extension and semaphorin function. We conclude that MAP6 is critical to interface guidance molecules with intracellular signalling effectors during the development of cerebral axon tracts. Loss of the structural microtubule-associated protein 6 (MAP6) leads to neuronal differentiation defects that are independent of MAP6's microtubule-binding properties. Here the authors establish a functional link between MAP6 and Semaphorin 3E signalling for proper formation of the fornix of the brain.
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Affiliation(s)
- Jean-Christophe Deloulme
- 1] INSERM, U836, F-38000 Grenoble, France [2] Univ. Grenoble Alpes, Grenoble Institut Neurosciences, F-38000 Grenoble, France
| | - Sylvie Gory-Fauré
- 1] INSERM, U836, F-38000 Grenoble, France [2] Univ. Grenoble Alpes, Grenoble Institut Neurosciences, F-38000 Grenoble, France
| | - Franck Mauconduit
- 1] INSERM, U836, F-38000 Grenoble, France [2] Univ. Grenoble Alpes, Grenoble Institut Neurosciences, F-38000 Grenoble, France
| | - Sophie Chauvet
- Aix-Marseille Université, CNRS, IBDM UMR 7288, 13288 Marseille, France
| | - Julie Jonckheere
- 1] INSERM, U836, F-38000 Grenoble, France [2] Univ. Grenoble Alpes, Grenoble Institut Neurosciences, F-38000 Grenoble, France
| | - Benoit Boulan
- 1] INSERM, U836, F-38000 Grenoble, France [2] Univ. Grenoble Alpes, Grenoble Institut Neurosciences, F-38000 Grenoble, France
| | - Erik Mire
- Aix-Marseille Université, CNRS, IBDM UMR 7288, 13288 Marseille, France
| | - Jing Xue
- Cell Signalling Unit, Children's Medical Research Institute, University of Sydney, Wentworthville, New South Wales 2145, Australia
| | - Marion Jany
- 1] INSERM, U836, F-38000 Grenoble, France [2] Univ. Grenoble Alpes, Grenoble Institut Neurosciences, F-38000 Grenoble, France
| | - Caroline Maucler
- 1] INSERM, U836, F-38000 Grenoble, France [2] Univ. Grenoble Alpes, Grenoble Institut Neurosciences, F-38000 Grenoble, France
| | - Agathe A Deparis
- 1] INSERM, U836, F-38000 Grenoble, France [2] Univ. Grenoble Alpes, Grenoble Institut Neurosciences, F-38000 Grenoble, France
| | - Olivier Montigon
- 1] INSERM, U836, F-38000 Grenoble, France [2] Univ. Grenoble Alpes, Grenoble Institut Neurosciences, F-38000 Grenoble, France [3] Centre Hospitalier Universitaire de Grenoble, IRMaGe, 38043 Grenoble, France [4] CNRS, UMS 3552, 38042 Grenoble, France
| | - Alexia Daoust
- 1] INSERM, U836, F-38000 Grenoble, France [2] Univ. Grenoble Alpes, Grenoble Institut Neurosciences, F-38000 Grenoble, France
| | - Emmanuel L Barbier
- 1] INSERM, U836, F-38000 Grenoble, France [2] Univ. Grenoble Alpes, Grenoble Institut Neurosciences, F-38000 Grenoble, France
| | - Christophe Bosc
- 1] INSERM, U836, F-38000 Grenoble, France [2] Univ. Grenoble Alpes, Grenoble Institut Neurosciences, F-38000 Grenoble, France
| | - Nicole Deglon
- 1] Lausanne University Hospital (CHUV), Department of Clinical Neurosciences (DNC), Laboratory of Cellular and Molecular Neurotherapies (LCMN), 1011 Lausanne, Switzerland [2] Lausanne University Hospital (CHUV), Neuroscience Research Center (CRN), 1011 Lausanne, Switzerland
| | - Jacques Brocard
- 1] INSERM, U836, F-38000 Grenoble, France [2] Univ. Grenoble Alpes, Grenoble Institut Neurosciences, F-38000 Grenoble, France
| | - Eric Denarier
- 1] INSERM, U836, F-38000 Grenoble, France [2] Univ. Grenoble Alpes, Grenoble Institut Neurosciences, F-38000 Grenoble, France [3] CEA, iRTSV, F-38000 Grenoble, France
| | - Isabelle Le Brun
- 1] Univ. Grenoble Alpes, Grenoble Institut Neurosciences, F-38000 Grenoble, France [2] INSERM, U1036, 38054 Grenoble, France [3] CEA, iRTSV, F-38000 Grenoble, France
| | - Karin Pernet-Gallay
- 1] INSERM, U836, F-38000 Grenoble, France [2] Univ. Grenoble Alpes, Grenoble Institut Neurosciences, F-38000 Grenoble, France
| | - Isabelle Vilgrain
- 1] Univ. Grenoble Alpes, Grenoble Institut Neurosciences, F-38000 Grenoble, France [2] INSERM, U1036, 38054 Grenoble, France [3] INSERM, U1036, 38054 Grenoble, France
| | - Phillip J Robinson
- Cell Signalling Unit, Children's Medical Research Institute, University of Sydney, Wentworthville, New South Wales 2145, Australia
| | - Hana Lahrech
- 1] INSERM, U836, F-38000 Grenoble, France [2] Univ. Grenoble Alpes, Grenoble Institut Neurosciences, F-38000 Grenoble, France [3] CEA, LETI, CLINATEC, MINATEC Campus, F-38054 Grenoble, France
| | - Fanny Mann
- Aix-Marseille Université, CNRS, IBDM UMR 7288, 13288 Marseille, France
| | - Annie Andrieux
- 1] INSERM, U836, F-38000 Grenoble, France [2] Univ. Grenoble Alpes, Grenoble Institut Neurosciences, F-38000 Grenoble, France [3] CEA, iRTSV, F-38000 Grenoble, France
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Gory-Fauré S, Windscheid V, Brocard J, Montessuit S, Tsutsumi R, Denarier E, Fukata Y, Bosc C, Delaroche J, Collomb N, Fukata M, Martinou JC, Pernet-Gallay K, Andrieux A. Non-microtubular localizations of microtubule-associated protein 6 (MAP6). PLoS One 2014; 9:e114905. [PMID: 25526643 PMCID: PMC4272302 DOI: 10.1371/journal.pone.0114905] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2014] [Accepted: 11/11/2014] [Indexed: 01/29/2023] Open
Abstract
MAP6 proteins (MAP6s), which include MAP6-N (also called Stable Tubule Only Polypeptide, or STOP) and MAP6d1 (MAP6 domain-containing protein 1, also called STOP-Like protein 21 kD, or SL21), bind to and stabilize microtubules. MAP6 deletion in mice severely alters integrated brain functions and is associated with synaptic defects, suggesting that MAP6s may also have alternative cellular roles. MAP6s reportedly associate with the Golgi apparatus through palmitoylation of their N-terminal domain, and specific isoforms have been shown to bind actin. Here, we use heterologous systems to investigate several biochemical properties of MAP6 proteins. We demonstrate that the three N-terminal cysteines of MAP6d1 are palmitoylated by a subset of DHHC-type palmitoylating enzymes. Analysis of the subcellular localization of palmitoylated MAP6d1, including electron microscopic analysis, reveals possible localization to the Golgi and the plasma membrane but no association with the endoplasmic reticulum. Moreover, we observed localization of MAP6d1 to mitochondria, which requires the N-terminus of the protein but does not require palmitoylation. We show that endogenous MAP6d1 localized at mitochondria in mature mice neurons as well as at the outer membrane and in the intermembrane space of purified mouse mitochondria. Last, we found that MAP6d1 can multimerize via a microtubule-binding module. Interestingly, most of these properties of MAP6d1 are shared by MAP6-N. Together, these results describe several properties of MAP6 proteins, including their intercellular localization and multimerization activity, which may be relevant to neuronal differentiation and synaptic functions.
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Affiliation(s)
- Sylvie Gory-Fauré
- Inserm, U836, Physiopathologie du cytosquelette, BP170, Grenoble, France
- University Grenoble Alpes, Grenoble Institut des Neurosciences, BP170, Grenoble, France
- * E-mail: (SGF); (AA)
| | - Vanessa Windscheid
- Inserm, U836, Physiopathologie du cytosquelette, BP170, Grenoble, France
- University Grenoble Alpes, Grenoble Institut des Neurosciences, BP170, Grenoble, France
| | - Jacques Brocard
- Inserm, U836, Physiopathologie du cytosquelette, BP170, Grenoble, France
- University Grenoble Alpes, Grenoble Institut des Neurosciences, BP170, Grenoble, France
| | - Sylvie Montessuit
- Department of Cell Biology, University of Geneva, Sciences III, Geneva, Switzerland
| | - Ryouhei Tsutsumi
- Division of Membrane Physiology, Department of Cell Physiology, National Institute for Physiological Sciences, Aichi, Japan
| | - Eric Denarier
- Inserm, U836, Physiopathologie du cytosquelette, BP170, Grenoble, France
- University Grenoble Alpes, Grenoble Institut des Neurosciences, BP170, Grenoble, France
- Commissariat à l'énergie atomique, Institut de Recherches en Technologies et Sciences pour le Vivant, Groupe Physiopathologie du Cytosquelette, Grenoble, France
| | - Yuko Fukata
- Division of Membrane Physiology, Department of Cell Physiology, National Institute for Physiological Sciences, Aichi, Japan
| | - Christophe Bosc
- Inserm, U836, Physiopathologie du cytosquelette, BP170, Grenoble, France
- University Grenoble Alpes, Grenoble Institut des Neurosciences, BP170, Grenoble, France
| | - Julie Delaroche
- Inserm, U836, Physiopathologie du cytosquelette, BP170, Grenoble, France
- University Grenoble Alpes, Grenoble Institut des Neurosciences, BP170, Grenoble, France
| | - Nora Collomb
- Inserm, U836, Physiopathologie du cytosquelette, BP170, Grenoble, France
- University Grenoble Alpes, Grenoble Institut des Neurosciences, BP170, Grenoble, France
| | - Masaki Fukata
- Division of Membrane Physiology, Department of Cell Physiology, National Institute for Physiological Sciences, Aichi, Japan
| | - Jean-Claude Martinou
- Department of Cell Biology, University of Geneva, Sciences III, Geneva, Switzerland
| | - Karin Pernet-Gallay
- Inserm, U836, Physiopathologie du cytosquelette, BP170, Grenoble, France
- University Grenoble Alpes, Grenoble Institut des Neurosciences, BP170, Grenoble, France
| | - Annie Andrieux
- Inserm, U836, Physiopathologie du cytosquelette, BP170, Grenoble, France
- University Grenoble Alpes, Grenoble Institut des Neurosciences, BP170, Grenoble, France
- Commissariat à l'énergie atomique, Institut de Recherches en Technologies et Sciences pour le Vivant, Groupe Physiopathologie du Cytosquelette, Grenoble, France
- * E-mail: (SGF); (AA)
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27
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Chesta ME, Carbajal A, Arce CA, Bisig CG. Serum-induced neurite retraction in CAD cells--involvement of an ATP-actin retractile system and the lack of microtubule-associated proteins. FEBS J 2014; 281:4767-78. [PMID: 25112570 DOI: 10.1111/febs.12967] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2014] [Revised: 06/23/2014] [Accepted: 08/08/2014] [Indexed: 11/28/2022]
Abstract
Cultured catecholamine-differentiated cells [which lack the microtubule-associated proteins (MAPs): MAP1B, MAP2, Tau, STOP, and Doublecortin] proliferate in the presence of fetal bovine serum, and, in its absence, cease dividing and generate processes similar to the neurites of normal neurons. The reintroduction of serum induces neurite retraction, and proliferation resumes. The neurite retraction process in catecholamine-differentiated cells was partially characterized in this study. Microtubules in the cells were found to be in a highly dynamic state, and tubulin in the microtubules consisted primarily of the tyrosinated and deacetylated isotypes. Increased levels of acetylated or Δ2-tubulin (which are normally absent) did not prevent serum-induced neurite retraction. Treatment of differentiated cells with lysophosphatidic acid or adenosine deaminase induced neurite retraction. Inhibition of Rho-associated protein kinase, ATP depletion and microfilament disruption each (individually) blocked serum-induced neurite retraction, suggesting that an ATP-dependent actomyosin system underlies the mechanism of neurite retraction. Nocodazole treatment induced neurite retraction, but this effect was blocked by pretreatment with the microtubule-stabilizing drug paclitaxel (Taxol). Paclitaxel did not prevent serum-induced or lysophosphatidic acid-induced retraction, suggesting that integrity of microtubules (despite their dynamic state) is necessary to maintain neurite elongation, and that paclitaxel-induced stabilization alone is not sufficient to resist the retraction force induced by serum. Transfection with green fluorescent protein-Tau conferred resistance to retraction caused by serum. We hypothesize that, in normal neurons (cultured or in vivo), MAPs are necessary not only to stabilize microtubules, but also to establish interactions with other cytoskeletal or membrane components to form a stable structure capable of resisting the retraction force.
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Affiliation(s)
- María E Chesta
- Centro de Investigaciones en Química Biológica de Córdoba (CIQUIBIC), UNC-CONICET, Departamento de Química Biológica, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Argentina
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28
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Toriumi K, Ikami M, Kondo M, Mouri A, Koseki T, Ibi D, Furukawa-Hibi Y, Nagai T, Mamiya T, Nitta A, Yamada K, Nabeshima T. SHATI/NAT8L regulates neurite outgrowth via microtubule stabilization. J Neurosci Res 2013; 91:1525-32. [DOI: 10.1002/jnr.23273] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2013] [Revised: 04/09/2013] [Accepted: 06/06/2013] [Indexed: 11/11/2022]
Affiliation(s)
- Kazuya Toriumi
- Department of Chemical Pharmacology; Graduate School of Pharmaceutical Sciences, Meijo University; Nagoya Japan
- The Academic Frontier Project for Private University, Comparative Cognitive Science Institutes, Meijo University; Nagoya Japan
| | - Miki Ikami
- Department of Chemical Pharmacology; Graduate School of Pharmaceutical Sciences, Meijo University; Nagoya Japan
| | - Mizuki Kondo
- Department of Chemical Pharmacology; Graduate School of Pharmaceutical Sciences, Meijo University; Nagoya Japan
| | - Akihiro Mouri
- Department of Chemical Pharmacology; Graduate School of Pharmaceutical Sciences, Meijo University; Nagoya Japan
| | - Takenao Koseki
- Department of Chemical Pharmacology; Graduate School of Pharmaceutical Sciences, Meijo University; Nagoya Japan
- The Academic Frontier Project for Private University, Comparative Cognitive Science Institutes, Meijo University; Nagoya Japan
| | - Daisuke Ibi
- Department of Chemical Pharmacology; Graduate School of Pharmaceutical Sciences, Meijo University; Nagoya Japan
- Department of Neuropsychopharmacology and Hospital Pharmacy; Nagoya University Graduate School of Medicine; Nagoya Japan
- Department of Regional Pharmaceutical Care and Sciences; Graduate School of Pharmaceutical Sciences, Meijo University; Nagoya Japan
| | - Yoko Furukawa-Hibi
- Department of Neuropsychopharmacology and Hospital Pharmacy; Nagoya University Graduate School of Medicine; Nagoya Japan
| | - Taku Nagai
- Department of Neuropsychopharmacology and Hospital Pharmacy; Nagoya University Graduate School of Medicine; Nagoya Japan
| | - Takayoshi Mamiya
- Department of Chemical Pharmacology; Graduate School of Pharmaceutical Sciences, Meijo University; Nagoya Japan
- The Academic Frontier Project for Private University, Comparative Cognitive Science Institutes, Meijo University; Nagoya Japan
| | - Atsumi Nitta
- Department of Pharmaceutical Therapy and Neuropharmacology, Faculty of Pharmaceutical Science; Graduate School of Medicine and Pharmaceutical Science, University of Toyama; Toyama Japan
| | - Kiyofumi Yamada
- Department of Neuropsychopharmacology and Hospital Pharmacy; Nagoya University Graduate School of Medicine; Nagoya Japan
| | - Toshitaka Nabeshima
- Department of Chemical Pharmacology; Graduate School of Pharmaceutical Sciences, Meijo University; Nagoya Japan
- The Academic Frontier Project for Private University, Comparative Cognitive Science Institutes, Meijo University; Nagoya Japan
- Department of Regional Pharmaceutical Care and Sciences; Graduate School of Pharmaceutical Sciences, Meijo University; Nagoya Japan
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29
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Volle J, Brocard J, Saoud M, Gory-Faure S, Brunelin J, Andrieux A, Suaud-Chagny MF. Reduced expression of STOP/MAP6 in mice leads to cognitive deficits. Schizophr Bull 2013; 39:969-78. [PMID: 23002183 PMCID: PMC3756782 DOI: 10.1093/schbul/sbs113] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
BACKGROUND STOP/MAP6 null (KO) mice recapitulate behavioral abnormalities related to positive and negative symptoms and cognitive deficits of schizophrenia. Here, we investigated whether decreased expression of STOP/MAP6 proteins in heterozygous mice (only one allele expressed) would result in abnormal behavior related to those displayed by STOP null mice. METHODS Using a comprehensive test battery, we investigated the behavioral phenotype of STOP heterozygous (Het) mice compared with STOP KO and wild type (WT) mice on animals raised either in standard conditions (controls) or submitted to maternal deprivation. RESULTS Control Het mice displayed prominent deficits in social interaction and learning, resembling KO mice. In contrast, they exhibited short-lasting locomotor hyperreactivity to acute mild stress and no impaired locomotor response to amphetamine, much like WT mice. Additionally, perinatal stress deteriorated Het mouse phenotype by exacerbating alterations related to positive symptoms such as their locomotor reactivity to acute mild stress and psychostimulant challenge. CONCLUSION Results show that the dosage of susceptibility genes modulates their putative phenotypic contribution and that STOP expression has a high penetrance on cognitive abilities. Hence, STOP Het mice might be useful to investigate cognitive defects related to those observed in mental diseases and ultimately might be a valuable experimental model to evaluate preventive treatments.
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Affiliation(s)
- Julien Volle
- Université de Lyon, Lyon, F-69003, France; Université Lyon 1, Lyon, EA 4615
| | - Jacques Brocard
- Institut National de la Santé et de la Recherche Médicale Unité 836, Institut des Neurosciences de Grenoble, Université Joseph Fourier, 38042 Grenoble Cedex 9, France;,Groupe Physiopathologie du Cytosquelette, Institut de Recherches en Technologies et Sciences pour le Vivant Direction des Sciences du Vivant, Commissariat à l’Énergie Atomique, 38054 Grenoble Cedex 9, France
| | - Mohamed Saoud
- Université de Lyon, Lyon, F-69003, France; Université Lyon 1, Lyon, EA 4615;,Centre Hospitalier le Vinatier, F-69677 Bron Cedex, France
| | - Sylvie Gory-Faure
- Institut National de la Santé et de la Recherche Médicale Unité 836, Institut des Neurosciences de Grenoble, Université Joseph Fourier, 38042 Grenoble Cedex 9, France;,Groupe Physiopathologie du Cytosquelette, Institut de Recherches en Technologies et Sciences pour le Vivant Direction des Sciences du Vivant, Commissariat à l’Énergie Atomique, 38054 Grenoble Cedex 9, France
| | - Jérôme Brunelin
- Université de Lyon, Lyon, F-69003, France; Université Lyon 1, Lyon, EA 4615;,Centre Hospitalier le Vinatier, F-69677 Bron Cedex, France
| | - Annie Andrieux
- Institut National de la Santé et de la Recherche Médicale Unité 836, Institut des Neurosciences de Grenoble, Université Joseph Fourier, 38042 Grenoble Cedex 9, France;,Groupe Physiopathologie du Cytosquelette, Institut de Recherches en Technologies et Sciences pour le Vivant Direction des Sciences du Vivant, Commissariat à l’Énergie Atomique, 38054 Grenoble Cedex 9, France
| | - Marie-Françoise Suaud-Chagny
- Université de Lyon, Lyon, F-69003, France; Université Lyon 1, Lyon, EA 4615;,Centre Hospitalier le Vinatier, F-69677 Bron Cedex, France;,To whom correspondence should be addressed; EA 4615, Pôle Est - Pr d’Amato, CH le vinatier, 95 bd Pinel, 69677 Bron cedex, France; tel: +33 4 37 91 55 65, fax: +33 4 37 91 55 49, e-mail:
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30
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Consciousness in the universe: a review of the 'Orch OR' theory. Phys Life Rev 2013; 11:39-78. [PMID: 24070914 DOI: 10.1016/j.plrev.2013.08.002] [Citation(s) in RCA: 223] [Impact Index Per Article: 20.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2013] [Accepted: 08/05/2013] [Indexed: 11/20/2022]
Abstract
The nature of consciousness, the mechanism by which it occurs in the brain, and its ultimate place in the universe are unknown. We proposed in the mid 1990's that consciousness depends on biologically 'orchestrated' coherent quantum processes in collections of microtubules within brain neurons, that these quantum processes correlate with, and regulate, neuronal synaptic and membrane activity, and that the continuous Schrödinger evolution of each such process terminates in accordance with the specific Diósi-Penrose (DP) scheme of 'objective reduction' ('OR') of the quantum state. This orchestrated OR activity ('Orch OR') is taken to result in moments of conscious awareness and/or choice. The DP form of OR is related to the fundamentals of quantum mechanics and space-time geometry, so Orch OR suggests that there is a connection between the brain's biomolecular processes and the basic structure of the universe. Here we review Orch OR in light of criticisms and developments in quantum biology, neuroscience, physics and cosmology. We also introduce a novel suggestion of 'beat frequencies' of faster microtubule vibrations as a possible source of the observed electro-encephalographic ('EEG') correlates of consciousness. We conclude that consciousness plays an intrinsic role in the universe.
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31
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Lefèvre J, Savarin P, Gans P, Hamon L, Clément MJ, David MO, Bosc C, Andrieux A, Curmi PA. Structural basis for the association of MAP6 protein with microtubules and its regulation by calmodulin. J Biol Chem 2013; 288:24910-22. [PMID: 23831686 DOI: 10.1074/jbc.m113.457267] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
Microtubules are highly dynamic αβ-tubulin polymers. In vitro and in living cells, microtubules are most often cold- and nocodazole-sensitive. When present, the MAP6/STOP family of proteins protects microtubules from cold- and nocodazole-induced depolymerization but the molecular and structure determinants by which these proteins stabilize microtubules remain under debate. We show here that a short protein fragment from MAP6-N, which encompasses its Mn1 and Mn2 modules (MAP6(90-177)), recapitulates the function of the full-length MAP6-N protein toward microtubules, i.e. its ability to stabilize microtubules in vitro and in cultured cells in ice-cold conditions or in the presence of nocodazole. We further show for the first time, using biochemical assays and NMR spectroscopy, that these effects result from the binding of MAP6(90-177) to microtubules with a 1:1 MAP6(90-177):tubulin heterodimer stoichiometry. NMR data demonstrate that the binding of MAP6(90-177) to microtubules involve its two Mn modules but that a single one is also able to interact with microtubules in a closely similar manner. This suggests that the Mn modules represent each a full microtubule binding domain and that MAP6 proteins may stabilize microtubules by bridging tubulin heterodimers from adjacent protofilaments or within a protofilament. Finally, we demonstrate that Ca(2+)-calmodulin competes with microtubules for MAP6(90-177) binding and that the binding mode of MAP6(90-177) to microtubules and Ca(2+)-calmodulin involves a common stretch of amino acid residues on the MAP6(90-177) side. This result accounts for the regulation of microtubule stability in cold condition by Ca(2+)-calmodulin.
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Affiliation(s)
- Julien Lefèvre
- Institut National de la Santé et de la Recherche Médicale (INSERM), UMR829, Laboratoire Structure-Activité des Biomolécules Normales et Pathologiques, Université Evry-Val d'Essonne, Evry 91025, France.
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32
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Moroz N, Guillaud L, Desai B, Kostyukova AS. Mutations changing tropomodulin affinity for tropomyosin alter neurite formation and extension. PeerJ 2013; 1:e7. [PMID: 23638401 PMCID: PMC3628370 DOI: 10.7717/peerj.7] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2012] [Accepted: 12/15/2012] [Indexed: 11/20/2022] Open
Abstract
Assembly of the actin cytoskeleton is an important part of formation of neurites in developing neurons. Tropomodulin, a tropomyosin-dependent capping protein for the pointed end of the actin filament, is one of the key players in this process. Tropomodulin binds tropomyosin in two binding sites. Tmod1 and Tmod2, tropomodulin isoforms found in neurons, were overexpressed in PC12 cells, a model system for neuronal differentiation. Tmod1 did not affect neuronal differentiation; while cells expressing Tmod2 showed a significant reduction in the number and the length of neurites. Both tropomodulins bind short α-, γ- and δ-tropomyosin isoforms. Mutations in one of the tropomyosin-binding sites of Tmod1, which increased its affinity to short γ- and δ-tropomyosin isoforms, caused a decrease in binding short α-tropomyosin isoforms along with a 2-fold decrease in the length of neurites. Our data demonstrate that Tmod1 is involved in neuronal differentiation for proper neurite formation and outgrowth, and that Tmod2 inhibits these processes. The mutations in the tropomyosin-binding site of Tmod1 impair neurite outgrowth, suggesting that the integrity of this binding site is critical for the proper function of Tmod1 during neuronal differentiation.
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Affiliation(s)
- Natalia Moroz
- Voiland School of Chemical Engineering and Bioengineering, Washington State University, Pullman, WA, USA
| | - Laurent Guillaud
- Cellular and Molecular Synaptic Function Unit, Okinawa Institute of Science and Technology - Graduate University, Kunigami, Okinawa, Japan
| | - Brinda Desai
- Department of Neuroscience and Cell Biology, Robert Wood Johnson Medical School, Piscataway, NJ, USA
| | - Alla S Kostyukova
- Voiland School of Chemical Engineering and Bioengineering, Washington State University, Pullman, WA, USA.,Department of Neuroscience and Cell Biology, Robert Wood Johnson Medical School, Piscataway, NJ, USA
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33
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34
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Ghosh-Roy A, Goncharov A, Jin Y, Chisholm AD. Kinesin-13 and tubulin posttranslational modifications regulate microtubule growth in axon regeneration. Dev Cell 2012; 23:716-28. [PMID: 23000142 DOI: 10.1016/j.devcel.2012.08.010] [Citation(s) in RCA: 111] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2012] [Revised: 07/18/2012] [Accepted: 08/20/2012] [Indexed: 11/16/2022]
Abstract
The microtubule (MT) cytoskeleton of a mature axon is maintained in a stabilized steady state, yet after axonal injury it can be transformed into a dynamic structure capable of supporting axon regrowth. Using Caenorhabditis elegans mechanosensory axons and in vivo imaging, we find that, in mature axons, the growth of MTs is restricted in the steady state by the depolymerizing kinesin-13 family member KLP-7. After axon injury, we observe a two-phase process of MT growth upregulation. First, the number of growing MTs increases at the injury site, concomitant with local downregulation of KLP-7. A second phase of persistent MT growth requires the cytosolic carboxypeptidase CCPP-6, which promotes Δ2 modification of α-tubulin. Both phases of MT growth are coordinated by the DLK-1 MAP kinase cascade. Our results define how the stable MT cytoskeleton of a mature neuron is converted into the dynamically growing MT cytoskeleton of a regrowing axon.
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Affiliation(s)
- Anindya Ghosh-Roy
- Division of Biological Sciences, Section of Neurobiology, University of California, San Diego, La Jolla, CA 92093, USA
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35
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Delphin C, Bouvier D, Seggio M, Couriol E, Saoudi Y, Denarier E, Bosc C, Valiron O, Bisbal M, Arnal I, Andrieux A. MAP6-F is a temperature sensor that directly binds to and protects microtubules from cold-induced depolymerization. J Biol Chem 2012; 287:35127-35138. [PMID: 22904321 DOI: 10.1074/jbc.m112.398339] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Microtubules are dynamic structures that present the peculiar characteristic to be ice-cold labile in vitro. In vivo, microtubules are protected from ice-cold induced depolymerization by the widely expressed MAP6/STOP family of proteins. However, the mechanism by which MAP6 stabilizes microtubules at 4 °C has not been identified. Moreover, the microtubule cold sensitivity and therefore the needs for microtubule stabilization in the wide range of temperatures between 4 and 37 °C are unknown. This is of importance as body temperatures of animals can drop during hibernation or torpor covering a large range of temperatures. Here, we show that in the absence of MAP6, microtubules in cells below 20 °C rapidly depolymerize in a temperature-dependent manner whereas they are stabilized in the presence of MAP6. We further show that in cells, MAP6-F binding to and stabilization of microtubules is temperature- dependent and very dynamic, suggesting a direct effect of the temperature on the formation of microtubule/MAP6 complex. We also demonstrate using purified proteins that MAP6-F binds directly to microtubules through its Mc domain. This binding is temperature-dependent and coincides with progressive conformational changes of the Mc domain as revealed by circular dichroism. Thus, MAP6 might serve as a temperature sensor adapting its conformation according to the temperature to maintain the cellular microtubule network in organisms exposed to temperature decrease.
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Affiliation(s)
- Christian Delphin
- Team 1 Physiopathology of Cytoskeleton; Commissariat à I'Energie Atomique, Institut National de la Santé et de la Recherche Médicale, U836-GIN iRTSV-GPC, Site Santé La Tronche, BP170, 38042 Grenoble, Cedex 9, France.
| | - Denis Bouvier
- the European Molecular Biology Laboratory, Grenoble Outstation, 6 rue Jules Horowitz, BP181, 38042 Grenoble Cedex 9, France
| | - Maxime Seggio
- Team 1 Physiopathology of Cytoskeleton; Commissariat à I'Energie Atomique, Institut National de la Santé et de la Recherche Médicale, U836-GIN iRTSV-GPC, Site Santé La Tronche, BP170, 38042 Grenoble, Cedex 9, France
| | - Emilie Couriol
- Team 1 Physiopathology of Cytoskeleton; Commissariat à I'Energie Atomique, Institut National de la Santé et de la Recherche Médicale, U836-GIN iRTSV-GPC, Site Santé La Tronche, BP170, 38042 Grenoble, Cedex 9, France
| | - Yasmina Saoudi
- Team 1 Physiopathology of Cytoskeleton; Commissariat à I'Energie Atomique, Institut National de la Santé et de la Recherche Médicale, U836-GIN iRTSV-GPC, Site Santé La Tronche, BP170, 38042 Grenoble, Cedex 9, France
| | - Eric Denarier
- Team 1 Physiopathology of Cytoskeleton; Commissariat à I'Energie Atomique, Institut National de la Santé et de la Recherche Médicale, U836-GIN iRTSV-GPC, Site Santé La Tronche, BP170, 38042 Grenoble, Cedex 9, France
| | - Christophe Bosc
- Team 1 Physiopathology of Cytoskeleton; Commissariat à I'Energie Atomique, Institut National de la Santé et de la Recherche Médicale, U836-GIN iRTSV-GPC, Site Santé La Tronche, BP170, 38042 Grenoble, Cedex 9, France
| | - Odile Valiron
- Team 1 Physiopathology of Cytoskeleton; Commissariat à I'Energie Atomique, Institut National de la Santé et de la Recherche Médicale, U836-GIN iRTSV-GPC, Site Santé La Tronche, BP170, 38042 Grenoble, Cedex 9, France
| | - Mariano Bisbal
- Team 1 Physiopathology of Cytoskeleton; Commissariat à I'Energie Atomique, Institut National de la Santé et de la Recherche Médicale, U836-GIN iRTSV-GPC, Site Santé La Tronche, BP170, 38042 Grenoble, Cedex 9, France
| | - Isabelle Arnal
- Team 13 Dynamic and Structural Regulation of Cytoskeleton, Institut National de la Santé et de la Recherche Médicale, U836-GIN, Site Santé La Tronche, BP170, 38042 Grenoble, Cedex 9, France
| | - Annie Andrieux
- Team 1 Physiopathology of Cytoskeleton; Commissariat à I'Energie Atomique, Institut National de la Santé et de la Recherche Médicale, U836-GIN iRTSV-GPC, Site Santé La Tronche, BP170, 38042 Grenoble, Cedex 9, France
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Kulkarni VA, Firestein BL. The dendritic tree and brain disorders. Mol Cell Neurosci 2012; 50:10-20. [DOI: 10.1016/j.mcn.2012.03.005] [Citation(s) in RCA: 242] [Impact Index Per Article: 20.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2012] [Accepted: 03/09/2012] [Indexed: 01/21/2023] Open
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Arama J, Boulay AC, Bosc C, Delphin C, Loew D, Rostaing P, Amigou E, Ezan P, Wingertsmann L, Guillaud L, Andrieux A, Giaume C, Cohen-Salmon M. Bmcc1s, a novel brain-isoform of Bmcc1, affects cell morphology by regulating MAP6/STOP functions. PLoS One 2012; 7:e35488. [PMID: 22523599 PMCID: PMC3327665 DOI: 10.1371/journal.pone.0035488] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2011] [Accepted: 03/16/2012] [Indexed: 12/21/2022] Open
Abstract
The BCH (BNIP2 and Cdc42GAP Homology) domain-containing protein Bmcc1/Prune2 is highly enriched in the brain and is involved in the regulation of cytoskeleton dynamics and cell survival. However, the molecular mechanisms accounting for these functions are poorly defined. Here, we have identified Bmcc1s, a novel isoform of Bmcc1 predominantly expressed in the mouse brain. In primary cultures of astrocytes and neurons, Bmcc1s localized on intermediate filaments and microtubules and interacted directly with MAP6/STOP, a microtubule-binding protein responsible for microtubule cold stability. Bmcc1s overexpression inhibited MAP6-induced microtubule cold stability by displacing MAP6 away from microtubules. It also resulted in the formation of membrane protrusions for which MAP6 was a necessary cofactor of Bmcc1s. This study identifies Bmcc1s as a new MAP6 interacting protein able to modulate MAP6-induced microtubule cold stability. Moreover, it illustrates a novel mechanism by which Bmcc1 regulates cell morphology.
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Affiliation(s)
- Jessica Arama
- Collège de France, Center for Interdisciplinary Research in Biology (CIRB)/Centre National de la Recherche Scientifique, Unité Mixte de Recherche 7241/Institut National de la Santé et de la Recherche Médicale U1050, Paris, France
- University Pierre et Marie Curie, ED, N°158, Paris, France
- MEMOLIFE Laboratory of Excellence and Paris Science Lettre Research University, Paris, France
| | - Anne-Cécile Boulay
- Collège de France, Center for Interdisciplinary Research in Biology (CIRB)/Centre National de la Recherche Scientifique, Unité Mixte de Recherche 7241/Institut National de la Santé et de la Recherche Médicale U1050, Paris, France
- University Pierre et Marie Curie, ED, N°158, Paris, France
- MEMOLIFE Laboratory of Excellence and Paris Science Lettre Research University, Paris, France
| | - Christophe Bosc
- Equipe Physiopathologie du Cytosquelette, Institut National de la Santé et de la Recherche Médicale U836, Institut des Neurosciences, Université Joseph Fourier, Faculté de Médecine, Domaine de la Merci, La Tronche, France
| | - Christian Delphin
- Equipe Physiopathologie du Cytosquelette, Institut National de la Santé et de la Recherche Médicale U836, Institut des Neurosciences, Université Joseph Fourier, Faculté de Médecine, Domaine de la Merci, La Tronche, France
| | - Damarys Loew
- Institut Curie, Laboratory of Proteomic Mass Spectrometry, Paris, France
| | - Philippe Rostaing
- Institut de Biologie de l'Ecole Normale Supérieure (IBENS), Institut National de la Santé et de la Recherche Médicale U1024, Paris, France
| | - Edwige Amigou
- Collège de France, Center for Interdisciplinary Research in Biology (CIRB)/Centre National de la Recherche Scientifique, Unité Mixte de Recherche 7241/Institut National de la Santé et de la Recherche Médicale U1050, Paris, France
- University Pierre et Marie Curie, ED, N°158, Paris, France
- MEMOLIFE Laboratory of Excellence and Paris Science Lettre Research University, Paris, France
| | - Pascal Ezan
- Collège de France, Center for Interdisciplinary Research in Biology (CIRB)/Centre National de la Recherche Scientifique, Unité Mixte de Recherche 7241/Institut National de la Santé et de la Recherche Médicale U1050, Paris, France
- University Pierre et Marie Curie, ED, N°158, Paris, France
- MEMOLIFE Laboratory of Excellence and Paris Science Lettre Research University, Paris, France
| | - Laure Wingertsmann
- Institut de Biologie de l'Ecole Normale Supérieure (IBENS), Institut National de la Santé et de la Recherche Médicale U1024, Paris, France
| | - Laurent Guillaud
- Cell and Molecular Synaptic Function Unit, Okinawa Institute of Science and Technology, Okinawa, Japan
| | - Annie Andrieux
- Equipe Physiopathologie du Cytosquelette, Institut National de la Santé et de la Recherche Médicale U836, Institut des Neurosciences, Université Joseph Fourier, Faculté de Médecine, Domaine de la Merci, La Tronche, France
| | - Christian Giaume
- Collège de France, Center for Interdisciplinary Research in Biology (CIRB)/Centre National de la Recherche Scientifique, Unité Mixte de Recherche 7241/Institut National de la Santé et de la Recherche Médicale U1050, Paris, France
- University Pierre et Marie Curie, ED, N°158, Paris, France
- MEMOLIFE Laboratory of Excellence and Paris Science Lettre Research University, Paris, France
| | - Martine Cohen-Salmon
- Collège de France, Center for Interdisciplinary Research in Biology (CIRB)/Centre National de la Recherche Scientifique, Unité Mixte de Recherche 7241/Institut National de la Santé et de la Recherche Médicale U1050, Paris, France
- University Pierre et Marie Curie, ED, N°158, Paris, France
- MEMOLIFE Laboratory of Excellence and Paris Science Lettre Research University, Paris, France
- * E-mail:
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Dacheux D, Landrein N, Thonnus M, Gilbert G, Sahin A, Wodrich H, Robinson DR, Bonhivers M. A MAP6-related protein is present in protozoa and is involved in flagellum motility. PLoS One 2012; 7:e31344. [PMID: 22355359 PMCID: PMC3280300 DOI: 10.1371/journal.pone.0031344] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2011] [Accepted: 01/06/2012] [Indexed: 12/25/2022] Open
Abstract
In vertebrates the microtubule-associated proteins MAP6 and MAP6d1 stabilize cold-resistant microtubules. Cilia and flagella have cold-stable microtubules but MAP6 proteins have not been identified in these organelles. Here, we describe TbSAXO as the first MAP6-related protein to be identified in a protozoan, Trypanosoma brucei. Using a heterologous expression system, we show that TbSAXO is a microtubule stabilizing protein. Furthermore we identify the domains of the protein responsible for microtubule binding and stabilizing and show that they share homologies with the microtubule-stabilizing Mn domains of the MAP6 proteins. We demonstrate, in the flagellated parasite, that TbSAXO is an axonemal protein that plays a role in flagellum motility. Lastly we provide evidence that TbSAXO belongs to a group of MAP6-related proteins (SAXO proteins) present only in ciliated or flagellated organisms ranging from protozoa to mammals. We discuss the potential roles of the SAXO proteins in cilia and flagella function.
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Affiliation(s)
- Denis Dacheux
- Microbiologie Fondamentale et Pathogénicité, Université de Bordeaux, UMR 5234, Bordeaux, France
- Microbiologie Fondamentale et Pathogénicité, CNRS, UMR 5234, Bordeaux, France
- Microbiologie Fondamentale et Pathogénicité, Institut Polytechnique de Bordeaux, UMR 5234, Bordeaux, France
| | - Nicolas Landrein
- Microbiologie Fondamentale et Pathogénicité, Université de Bordeaux, UMR 5234, Bordeaux, France
- Microbiologie Fondamentale et Pathogénicité, CNRS, UMR 5234, Bordeaux, France
| | - Magali Thonnus
- Microbiologie Fondamentale et Pathogénicité, Université de Bordeaux, UMR 5234, Bordeaux, France
- Microbiologie Fondamentale et Pathogénicité, CNRS, UMR 5234, Bordeaux, France
| | - Guillaume Gilbert
- Microbiologie Fondamentale et Pathogénicité, Université de Bordeaux, UMR 5234, Bordeaux, France
- Microbiologie Fondamentale et Pathogénicité, CNRS, UMR 5234, Bordeaux, France
| | - Annelise Sahin
- Microbiologie Fondamentale et Pathogénicité, Université de Bordeaux, UMR 5234, Bordeaux, France
- Microbiologie Fondamentale et Pathogénicité, CNRS, UMR 5234, Bordeaux, France
| | - Harald Wodrich
- Microbiologie Fondamentale et Pathogénicité, Université de Bordeaux, UMR 5234, Bordeaux, France
- Microbiologie Fondamentale et Pathogénicité, CNRS, UMR 5234, Bordeaux, France
| | - Derrick R. Robinson
- Microbiologie Fondamentale et Pathogénicité, Université de Bordeaux, UMR 5234, Bordeaux, France
- Microbiologie Fondamentale et Pathogénicité, CNRS, UMR 5234, Bordeaux, France
| | - Mélanie Bonhivers
- Microbiologie Fondamentale et Pathogénicité, Université de Bordeaux, UMR 5234, Bordeaux, France
- Microbiologie Fondamentale et Pathogénicité, CNRS, UMR 5234, Bordeaux, France
- * E-mail:
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Kiyasova V, Gaspar P. Development of raphe serotonin neurons from specification to guidance. Eur J Neurosci 2011; 34:1553-62. [DOI: 10.1111/j.1460-9568.2011.07910.x] [Citation(s) in RCA: 80] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
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Myotonic dystrophy type 1-associated CTG repeats disturb the expression and subcellular distribution of microtubule-associated proteins MAP1A, MAP2, and MAP6/STOP in PC12 cells. Mol Biol Rep 2011; 39:415-24. [PMID: 21567201 DOI: 10.1007/s11033-011-0753-y] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2010] [Accepted: 04/27/2011] [Indexed: 02/04/2023]
Abstract
To study the effect of DM1-associated CTG repeats on neuronal function, we developed a PC12 cell-based model that constitutively expresses the DMPK gene 3'-untranslated region with 90 CTG repeats (CTG90 cells). As CTG90 cells exhibit impaired neurite outgrowth and as microtubule-associated proteins (MAPs) are crucial for microtubule stability, we analyzed whether MAPs are a target of CTG repeats. NGF induces mRNA expression of Map2, Map1a and Map6 in control cells (PC12 cells transfected with the empty vector), but this induction is abolished for Map2 and Map1a in CTG90 cells. MAP2 and MAP6/STOP proteins decrease in NGF-treated CTG90 cells, whereas MAP1A increases. Data suggest that CTG repeats might alter somehow the expression of MAPs, which appears to be related with CTG90 cell-deficient neurite outgrowth. Decreased MAP2 levels found in the hippocampus of a DM1 mouse model indicates that targeting of MAPs expression by CTG repeats might be relevant to DM1.
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Hameroff SR, Craddock TJA, Tuszynski JA. "Memory bytes" - molecular match for CaMKII phosphorylation encoding of microtubule lattices. J Integr Neurosci 2011; 9:253-67. [PMID: 21064217 DOI: 10.1142/s0219635210002482] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2010] [Accepted: 09/02/2010] [Indexed: 11/18/2022] Open
Abstract
Learning, memory and long-term potentiation (LTP) are supported by factors including post-synaptic calcium ion flux activating and transforming the hexagonal calcium-calmodulin kinase II (CaMKII) holoenzyme. Upon calcium-induced activation, up to six kinase domains extend upward, and up to six kinase domains extend downward from the CaMKII association domain, the fully activated holoenzyme resembling a robotic insect 20 nanometers in length. Each extended kinase domain can be phosphorylated, and able to phosphorylate other proteins, thus potentially further encoding synaptic information at intraneuronal molecular sites for memory storage, processing and distribution. Candidate sites for phosphorylation-encoded molecular memory include microtubules, cylindrical lattice polymers of the protein tubulin. Using molecular modeling, we find spatial dimensions and geometry of the six extended CaMKII kinase domains can precisely match those of microtubule hexagonal lattice neighborhoods (both A- and B-lattices), and show two feasible phosphorylation mechanisms. In one, phosphorylation sites (e.g., valine 208) on a CaMKII extended kinase domain interact with serine 444 on a C-terminal "tail" of tubulin. In the second, the CaMKII kinase domain unfurls, enabling phosphorylation sites to contact threonine and serine sites on the tubulin surface. We suggest sets of six CaMKII kinase domains phosphorylate hexagonal microtubule lattice neighborhoods collectively, e.g., conveying synaptic information as ordered arrays of six "bits", and thus a "byte", with (minimally) 2⁶ (64) possible bit states per CaMKII-microtubule interaction. We model two levels of interaction between CaMKII and microtubules, suggesting a testable framework for molecular memory encoding.
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Affiliation(s)
- Stuart R Hameroff
- Department of Anesthesiology, Center for Consciousness Studies, The University of Arizona Health Sciences Center, Tucson, Arizona 85724, USA
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Charlet A, Muller AH, Laux A, Kemmel V, Schweitzer A, Deloulme JC, Stuber D, Delalande F, Bianchi E, Van Dorsselaer A, Aunis D, Andrieux A, Poisbeau P, Goumon Y. Abnormal nociception and opiate sensitivity of STOP null mice exhibiting elevated levels of the endogenous alkaloid morphine. Mol Pain 2010; 6:96. [PMID: 21172011 PMCID: PMC3017033 DOI: 10.1186/1744-8069-6-96] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2010] [Accepted: 12/20/2010] [Indexed: 01/12/2023] Open
Abstract
BACKGROUND Mice deficient for the stable tubule only peptide (STOP) display altered dopaminergic neurotransmission associated with severe behavioural defects including disorganized locomotor activity. Endogenous morphine, which is present in nervous tissues and synthesized from dopamine, may contribute to these behavioral alterations since it is thought to play a role in normal and pathological neurotransmission. RESULTS In this study, we showed that STOP null brain structures, including cortex, hippocampus, cerebellum and spinal cord, contain high endogenous morphine amounts. The presence of elevated levels of morphine was associated with the presence of a higher density of mu opioid receptor with a higher affinity for morphine in STOP null brains. Interestingly, STOP null mice exhibited significantly lower nociceptive thresholds to thermal and mechanical stimulations. They also had abnormal behavioural responses to the administration of exogenous morphine and naloxone. Low dose of morphine (1 mg/kg, i.p.) produced a significant mechanical antinociception in STOP null mice whereas it has no effect on wild-type mice. High concentration of naloxone (1 mg/kg) was pronociceptive for both mice strain, a lower concentration (0.1 mg/kg) was found to increase the mean mechanical nociceptive threshold only in the case of STOP null mice. CONCLUSIONS Together, our data show that STOP null mice displayed elevated levels of endogenous morphine, as well as an increase of morphine receptor affinity and density in brain. This was correlated with hypernociception and impaired pharmacological sensitivity to mu opioid receptor ligands.
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Affiliation(s)
- Alexandre Charlet
- Institut des Neurosciences Cellulaires et Intégratives, Centre National de la Recherche Scientifique et Université de Strasbourg, Strasbourg, F-67084, France
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Fournet V, Jany M, Fabre V, Chali F, Orsal D, Schweitzer A, Andrieux A, Messanvi F, Giros B, Hamon M, Lanfumey L, Deloulme JC, Martres MP. The deletion of the microtubule-associated STOP protein affects the serotonergic mouse brain network. J Neurochem 2010; 115:1579-94. [PMID: 20969568 DOI: 10.1111/j.1471-4159.2010.07064.x] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
The deletion of microtubule-associated protein stable tubule only polypeptide (STOP) leads to neuroanatomical, biochemical and severe behavioral alterations in mice, partly alleviated by antipsychotics. Therefore, STOP knockout (KO) mice have been proposed as a model of some schizophrenia-like symptoms. Preliminary data showed decreased brain serotonin (5-HT) tissue levels in STOP KO mice. As literature data demonstrate various interactions between microtubule-associated proteins and 5-HT, we characterized some features of the serotonergic neurotransmission in STOP KO mice. In the brainstem, mutant mice displayed higher tissue 5-HT levels and in vivo synthesis rate, together with marked increases in 5-HT transporter densities and 5-HT1A autoreceptor levels and electrophysiological sensitivity, without modification of the serotonergic soma number. Conversely, in projection areas, STOP KO mice exhibited lower 5-HT levels and in vivo synthesis rate, associated with severe decreases in 5-HT transporter densities, possibly related to reduced serotonergic terminals. Mutant mice also displayed a deficit of adult hippocampal neurogenesis, probably related to both STOP deletion and 5-HT depletion. Finally, STOP KO mice exhibited a reduced anxiety- and, probably, an increased helpness-status, that could be because of the strong imbalance of the serotonin neurotransmission between somas and terminals. Altogether, these data suggested that STOP deletion elicited peculiar 5-HT disconnectivity.
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Affiliation(s)
- Vincent Fournet
- INSERM UMRS 952, CNRS UMR 7224, Université Pierre et Marie Curie, Paris, France
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Ochoa CD, Stevens T, Balczon R. Cold exposure reveals two populations of microtubules in pulmonary endothelia. Am J Physiol Lung Cell Mol Physiol 2010; 300:L132-8. [PMID: 20971804 DOI: 10.1152/ajplung.00185.2010] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Microtubules are composed of α-tubulin and β-tubulin dimers. Microtubules yield tubulin dimers when exposed to cold, which reassemble spontaneously to form microtubule fibers at 37°C. However, mammalian neurons, glial cells, and fibroblasts have cold-stable microtubules. While studying the microtubule toxicity mechanisms of the exotoxin Y from Pseudomonas aeruginosa in pulmonary microvascular endothelial cells, we observed that some endothelial microtubules were very difficult to disassemble in the cold. As a consequence, we designed studies to test the hypothesis that microvascular endothelium has a population of cold-stable microtubules. Pulmonary microvascular endothelial cells and HeLa cells (control) were grown under regular cell culture conditions, followed by exposure to an ice-cold water bath and a microtubule extraction protocol. Polymerized microtubules were detected by immunofluorescence confocal microscopy and Western blot analyses. After cold exposure, immunofluorescence revealed that the majority of HeLa cell microtubules disassembled, whereas a smaller population of endothelial cell microtubules disassembled. Immunoblot analyses showed that microvascular endothelial cells express the microtubule cold-stabilizing protein N-STOP (neuronal stable tubule-only polypeptides), and that N-STOP binds to endothelial microtubules after cold exposure, but not if microtubules are disassembled with nocodazole before cold exposure. Hence, pulmonary endothelia have a population of cold-stable microtubules.
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Affiliation(s)
- Cristhiaan D Ochoa
- Departments of Pharmacology, University of South Alabama, Mobile, Alabama 36688, USA
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Benardais K, Kasem B, Couegnas A, Samama B, Fernandez S, Schaeffer C, Antal MC, Job D, Schweitzer A, Andrieux A, Giersch A, Nehlig A, Boehm N. Loss of STOP protein impairs peripheral olfactory neurogenesis. PLoS One 2010; 5:e12753. [PMID: 20856814 PMCID: PMC2939889 DOI: 10.1371/journal.pone.0012753] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2010] [Accepted: 08/18/2010] [Indexed: 11/19/2022] Open
Abstract
Background STOP (Stable Tubulin-Only Polypeptide) null mice show behavioral deficits, impaired synaptic plasticity, decrease in synaptic vesicular pools and disturbances in dopaminergic transmission, and are considered a neurodevelopmental model of schizophrenia. Olfactory neurons highly express STOP protein and are continually generated throughout life. Experimentally-induced loss of olfactory neurons leads to epithelial regeneration within two months, providing a useful model to evaluate the role played by STOP protein in adult olfactory neurogenesis. Methodology/Principal Findings Immunocytochemistry and electron microscopy were used to study the structure of the glomerulus in the main olfactory bulb and neurogenesis in the neurosensorial epithelia. In STOP null mice, olfactory neurons showed presynaptic swellings with tubulovesicular profiles and autophagic-like structures. In olfactory and vomeronasal epithelia, there was an increase in neurons turnover, as shown by the increase in number of proliferating, apoptotic and immature cells with no changes in the number of mature neurons. Similar alterations in peripheral olfactory neurogenesis have been previously described in schizophrenia patients. In STOP null mice, regeneration of the olfactory epithelium did not modify these anomalies; moreover, regeneration resulted in abnormal organisation of olfactory terminals within the olfactory glomeruli in STOP null mice. Conclusions/Significance In conclusion, STOP protein seems to be involved in the establishment of synapses in the olfactory glomerulus. Our results indicate that the olfactory system of STOP null mice is a well-suited experimental model (1) for the study of the mechanism of action of STOP protein in synaptic function/plasticity and (2) for pathophysiological studies of the mechanisms of altered neuronal connections in schizophrenia.
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Affiliation(s)
- Karelle Benardais
- INSERM U666, Strasbourg, France
- Université de Strasbourg, Faculté de Médecine, Institut d'Histologie, Strasbourg, France
| | - Basem Kasem
- INSERM U666, Strasbourg, France
- Université de Strasbourg, Faculté de Médecine, Institut d'Histologie, Strasbourg, France
| | - Alice Couegnas
- INSERM U666, Strasbourg, France
- Université de Strasbourg, Faculté de Médecine, Institut d'Histologie, Strasbourg, France
| | - Brigitte Samama
- INSERM U666, Strasbourg, France
- Université de Strasbourg, Faculté de Médecine, Institut d'Histologie, Strasbourg, France
- Hôpitaux Universitaires de Strasbourg, Strasbourg, France
- * E-mail:
| | - Sebastien Fernandez
- Université de Strasbourg, Faculté de Médecine, Institut d'Histologie, Strasbourg, France
| | - Christiane Schaeffer
- INSERM U666, Strasbourg, France
- Université de Strasbourg, Faculté de Médecine, Institut d'Histologie, Strasbourg, France
- Hôpitaux Universitaires de Strasbourg, Strasbourg, France
| | - Maria-Cristina Antal
- INSERM U666, Strasbourg, France
- Université de Strasbourg, Faculté de Médecine, Institut d'Histologie, Strasbourg, France
- Hôpitaux Universitaires de Strasbourg, Strasbourg, France
| | - Didier Job
- INSERM U836, Grenoble Institut of Neurosciences, Grenoble, France; iRTSV-GPC, CEA-Grenoble, France; Université Joseph Fourrier, Grenoble, France
| | - Annie Schweitzer
- INSERM U836, Grenoble Institut of Neurosciences, Grenoble, France; iRTSV-GPC, CEA-Grenoble, France; Université Joseph Fourrier, Grenoble, France
| | - Annie Andrieux
- INSERM U836, Grenoble Institut of Neurosciences, Grenoble, France; iRTSV-GPC, CEA-Grenoble, France; Université Joseph Fourrier, Grenoble, France
| | | | | | - Nelly Boehm
- INSERM U666, Strasbourg, France
- Université de Strasbourg, Faculté de Médecine, Institut d'Histologie, Strasbourg, France
- Hôpitaux Universitaires de Strasbourg, Strasbourg, France
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Bisig CG, Chesta ME, Zampar GG, Purro SA, Santander VS, Arce CA. Lack of stabilized microtubules as a result of the absence of major maps in CAD cells does not preclude neurite formation. FEBS J 2009; 276:7110-23. [DOI: 10.1111/j.1742-4658.2009.07422.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Abstract
Neurofilaments assemble from three intermediate-filament proteins, contribute to the radial growth of axons, and are exceptionally stable. Microtubules are dynamic structures that assemble from tubulin dimers to support intracellular transport of molecules and organelles. We show here that neurofilaments, and other intermediate-filament proteins, contain motifs in their N-terminal domains that bind unassembled tubulin. Peptides containing such motifs inhibit the in vitro polymerization of microtubules and can be taken up by cultured cells in which they disrupt microtubules leading to altered cell shapes and an arrest of division. In transgenic mice in which neurofilaments are withheld from the axonal compartment, axonal tubulin accumulation is normal but microtubules assemble in excessive numbers. These observations suggest a model in which axonal neurofilaments modulate local microtubule assembly. This capacity also suggests novel mechanisms through which inherited or acquired disruptions in intermediate filaments might contribute to pathogenesis in multiple conditions.
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The microtubule network and neuronal morphogenesis: Dynamic and coordinated orchestration through multiple players. Mol Cell Neurosci 2009; 43:15-32. [PMID: 19660553 DOI: 10.1016/j.mcn.2009.07.012] [Citation(s) in RCA: 116] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2009] [Accepted: 07/27/2009] [Indexed: 11/24/2022] Open
Abstract
Nervous system function and plasticity rely on the complex architecture of neuronal networks elaborated during development, when neurons acquire their specific and complex shape. During neuronal morphogenesis, the formation and outgrowth of functionally and structurally distinct axons and dendrites require a coordinated and dynamic reorganization of the microtubule cytoskeleton involving numerous regulators. While most of these factors act directly on microtubules to stabilize them or promote their assembly, depolymerization or fragmentation, others are now emerging as essential regulators of neuronal differentiation by controlling tubulin availability and modulating microtubule dynamics. In this review, we recapitulate how the microtubule network is actively regulated during the successive phases of neuronal morphogenesis, and what are the specific roles of the various microtubule-regulating proteins in that process. We then describe the specific signaling pathways and inter-regulations that coordinate the different activities of these proteins to sustain neuronal development in response to environmental cues.
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McKemmish LK, Reimers JR, McKenzie RH, Mark AE, Hush NS. Penrose-Hameroff orchestrated objective-reduction proposal for human consciousness is not biologically feasible. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2009; 80:021912. [PMID: 19792156 DOI: 10.1103/physreve.80.021912] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/15/2008] [Revised: 05/29/2009] [Indexed: 05/28/2023]
Abstract
Penrose and Hameroff have argued that the conventional models of a brain function based on neural networks alone cannot account for human consciousness, claiming that quantum-computation elements are also required. Specifically, in their Orchestrated Objective Reduction (Orch OR) model [R. Penrose and S. R. Hameroff, J. Conscious. Stud. 2, 99 (1995)], it is postulated that microtubules act as quantum processing units, with individual tubulin dimers forming the computational elements. This model requires that the tubulin is able to switch between alternative conformational states in a coherent manner, and that this process be rapid on the physiological time scale. Here, the biological feasibility of the Orch OR proposal is examined in light of recent experimental studies on microtubule assembly and dynamics. It is shown that the tubulins do not possess essential properties required for the Orch OR proposal, as originally proposed, to hold. Further, we consider also recent progress in the understanding of the long-lived coherent motions in biological systems, a feature critical to Orch OR, and show that no reformation of the proposal based on known physical paradigms could lead to quantum computing within microtubules. Hence, the Orch OR model is not a feasible explanation of the origin of consciousness.
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Affiliation(s)
- Laura K McKemmish
- School of Chemistry, The University of Sydney, New South Wales 2006, Australia
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