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Lee S, Eyer J, Letournel F, Boumil E, Hall G, Shea TB. Neurofilaments form flexible bundles during neuritogenesis in culture and in mature axons in situ. J Neurosci Res 2019; 97:1306-1318. [PMID: 31304612 DOI: 10.1002/jnr.24482] [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: 02/16/2019] [Revised: 05/28/2019] [Accepted: 05/29/2019] [Indexed: 11/07/2022]
Abstract
Neurofilaments (NFs) undergo cation-dependent phospho-mediated associations with each other and other cytoskeletal elements that support axonal outgrowth. Progressive NF-NF associations generate a resident, bundled population that undergoes exchange with transporting NFs. We examined the properties of bundled NFs. Bundles did not always display a fully linear profile but curved and twisted at various points along the neurite length. Bundles retracted faster than neurites and retracted bundles did not expand following extraction with Triton, indicating that they coiled passively rather than due to pressure from the cell. Bundles consisted of helically wound NFs, which may provide flexibility necessary for turning of growing axons during pathfinding. Interactions between NFs and other cytoskeletal elements may be disrupted en masse during neurite retraction or regionally during remodeling. It is suggested that bundles within long axons that cannot be fully retracted into the soma could provide maintain proximal support yet still allow more distal flexibility for remodeling and changing direction during pathfinding.
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Affiliation(s)
- Sangmook Lee
- Laboratory for Neuroscience, Department of Biology Science, UMass Lowell, Lowell, Massachusetts
| | - Joel Eyer
- Institut de Biologie en Santé PBH-IRIS, Universitaire d'Angers, Angers, France
| | | | - Edward Boumil
- Center for Vision Research, SUNY Upstate, Syracuse, New York
| | - Garth Hall
- Laboratory for Neuroscience, Department of Biology Science, UMass Lowell, Lowell, Massachusetts
| | - Thomas B Shea
- Laboratory for Neuroscience, Department of Biology Science, UMass Lowell, Lowell, Massachusetts
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Boumil EF, Vohnoutka R, Lee S, Pant H, Shea TB. Assembly and turnover of neurofilaments in growing axonal neurites. Biol Open 2018; 7:bio.028795. [PMID: 29158321 PMCID: PMC5829495 DOI: 10.1242/bio.028795] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Neurofilaments (NFs) are thought to provide stability to the axon. We examined NF dynamics within axonal neurites of NB2a/d1 neuroblastoma by transient transfection with green fluorescent protein-tagged NF-heavy (GFP-H) under the control of a tetracycline-inducible promoter. Immunofluorescent and biochemical analyses demonstrated that GFP-H expressed early during neurite outgrowth associated with a population of centrally-situated, highly-phosphorylated crosslinked NFs along the length of axonal neurites (‘bundled NFs’). By contrast, GFP-H expressed after considerable neurite outgrowth displayed markedly reduced association with bundled NFs and was instead more evenly distributed throughout the axon. This differential localization was maintained for up to 2 weeks in culture. Once considerable neurite outgrowth had progressed, GFP that had previously associated with the NF bundle during early expression was irreversibly depleted by photobleaching. Cessation of expression allowed monitoring of NF turnover. GFP-H associated bundled NFs underwent slower decay than GFP-H associated with surrounding, less-phosphorylated NFs. Notably, GFP associated with bundled NFs underwent similar decay rates within the core and edges of this bundle. These results are consistent with previous demonstration of a resident NF population within axonal neurites, but suggest that this population is more dynamic than previously considered. Summary: Immunofluorescent and radiolabel analyses demonstrate that neurofilaments establish a resident population within growing axonal neurites that undergoes exchange with a surrounding, transporting pool.
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Affiliation(s)
- Edward F Boumil
- Laboratory for Neuroscience, University of Massachusetts Lowell, Lowell, MA 01854, USA
| | - Rishel Vohnoutka
- Laboratory for Neuroscience, University of Massachusetts Lowell, Lowell, MA 01854, USA
| | - Sangmook Lee
- Laboratory for Neuroscience, University of Massachusetts Lowell, Lowell, MA 01854, USA
| | - Harish Pant
- Cytoskeletal Protein Regulation Section, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD 20892 , USA
| | - Thomas B Shea
- Laboratory for Neuroscience, University of Massachusetts Lowell, Lowell, MA 01854, USA
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Dengler-Crish CM, Smith MA, Inman DM, Wilson GN, Young JW, Crish SD. Anterograde transport blockade precedes deficits in retrograde transport in the visual projection of the DBA/2J mouse model of glaucoma. Front Neurosci 2014; 8:290. [PMID: 25278826 PMCID: PMC4166356 DOI: 10.3389/fnins.2014.00290] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2014] [Accepted: 08/27/2014] [Indexed: 01/30/2023] Open
Abstract
Axonal transport deficits have been reported as an early pathology in several neurodegenerative disorders, including glaucoma. However, the progression and mechanisms of these deficits are poorly understood. Previous work suggests that anterograde transport is affected earlier and to a larger degree than retrograde transport, yet this has never been examined directly in vivo. Using combined anterograde and retrograde tract tracing methods, we examined the time-course of anterograde and retrograde transport deficits in the retinofugal projection in pre-glaucomatous (3 month-old) and glaucomatous (9–13 month old) DBA/2J mice. DBA/2J-Gpnmb+ mice were used as a control strain and were shown to have similar retinal ganglion cell densities as C57BL/6J control mice—a strain commonly investigated in the field of vision research. Using cholera toxin-B injections into the eye and FluoroGold injections into the superior colliculus (SC), we were able to measure anterograde and retrograde transport in the primary visual projection. In DBA/2J, anterograde transport from the retina to SC was decreased by 69% in the 9–10 month-old age group, while retrograde transport was only reduced by 23% from levels seen in pre-glaucomatous mice. Despite this minor reduction, retrograde transport remained largely intact in these glaucomatous age groups until 13-months of age. These findings indicate that axonal transport deficits occur in semi-functional axons that are still connected to their brain targets. Structural persistence as determined by presence of estrogen-related receptor beta label in the superficial SC was maintained beyond time-points where reductions in retrograde transport occurred, also supporting that transport deficits may be due to physiological or functional abnormalities as opposed to overt structural loss.
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Affiliation(s)
- Christine M Dengler-Crish
- Department of Pharmaceutical Sciences, Northeast Ohio Medical University Rootstown, OH, USA ; Department of Anatomy and Neurobiology, Northeast Ohio Medical University Rootstown, OH, USA
| | - Matthew A Smith
- Department of Pharmaceutical Sciences, Northeast Ohio Medical University Rootstown, OH, USA ; Integrated Pharmaceutical Medicine Graduate Program, Northeast Ohio Medical University Rootstown, OH, USA
| | - Denise M Inman
- Department of Pharmaceutical Sciences, Northeast Ohio Medical University Rootstown, OH, USA
| | - Gina N Wilson
- Department of Pharmaceutical Sciences, Northeast Ohio Medical University Rootstown, OH, USA ; Biomedical Sciences Graduate Program, Kent State University Kent, OH, USA
| | - Jesse W Young
- Department of Anatomy and Neurobiology, Northeast Ohio Medical University Rootstown, OH, USA
| | - Samuel D Crish
- Department of Pharmaceutical Sciences, Northeast Ohio Medical University Rootstown, OH, USA
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Shea TB, Lee S. The discontinuous nature of neurofilament transport accommodates both establishment and repair of the axonal neurofilament array. Cytoskeleton (Hoboken) 2012; 70:67-73. [PMID: 23124969 DOI: 10.1002/cm.21087] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2012] [Revised: 10/08/2012] [Accepted: 10/11/2012] [Indexed: 12/19/2022]
Abstract
Neurofilaments (NFs) provide structural support to axons. Timely and regional deposition of NFs is essential during axonogenesis, since progressive stabilization of proximal axons is essential to support continued pathfinding of distal axonal regions. NFs undergo short bursts of microtubule-mediated axonal transport interspersed by prolonged pauses. We demonstrate herein that it is this unique "on-off" method of axonal transport, coupled with the ability of NFs to form cation-dependent, phosphomediated lateral associations that allow neurons to mediate the orderly transition from exploratory process to stabilized axon following synaptogenesis. We further demonstrate how this transport method provides for NF maintenance following maturation and encompasses the potential for regeneration.
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Affiliation(s)
- Thomas B Shea
- Department of Biological Sciences, Center for Cellular Neurobiology and Neurodegeneration Research, University of Massachusetts, Lowell, One University Avenue, Lowell, MA 01854, USA.
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Searching for antigen epitope specificities in the monoclonal IgG molecules of patients with multiple myeloma. The description of a monoclonal antibody with a dynein-specific antigen epitope character. Ann Hematol 2011; 90:1227-8. [DOI: 10.1007/s00277-010-1148-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2010] [Accepted: 12/20/2010] [Indexed: 11/27/2022]
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King A, Dickson T, Blizzard C, Woodhouse A, Foster S, Chung R, Vickers J. Neuron–glia interactions underlie ALS-like axonal cytoskeletal pathology. Neurobiol Aging 2011; 32:459-69. [DOI: 10.1016/j.neurobiolaging.2009.04.004] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2009] [Revised: 03/24/2009] [Accepted: 04/06/2009] [Indexed: 01/24/2023]
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RNA processing pathways in amyotrophic lateral sclerosis. Neurogenetics 2010; 11:275-90. [PMID: 20349096 DOI: 10.1007/s10048-010-0239-4] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2009] [Accepted: 02/24/2010] [Indexed: 12/12/2022]
Abstract
RNA processing is a tightly regulated, highly complex pathway which includes RNA transcription, pre-mRNA splicing, editing, transportation, translation, and degradation of RNA. Over the past few years, several RNA processing genes have been shown to be mutated or genetically associated with amyotrophic lateral sclerosis (ALS), including the RNA-binding proteins TDP-43 and FUS/TLS. These findings suggest that RNA processing may represent a common pathogenic mechanism involved in development of ALS. In this review, we will discuss six ALS-related, RNA processing genes including their discovery, function, and commonalities.
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Del Barco DG, Pérez-Saad H, Rodríguez V, Marín J, Falcón V, Martín J, Cibrian D, Berlanga J. Therapeutic effect of the combined use of growth hormone releasing peptide-6 and epidermal growth factor in an axonopathy model. Neurotox Res 2010; 19:195-209. [PMID: 20169434 DOI: 10.1007/s12640-010-9160-8] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2009] [Revised: 01/13/2010] [Accepted: 02/03/2010] [Indexed: 12/13/2022]
Abstract
Amyotrophic lateral sclerosis (ALS) is a disease of the central nervous system characterized by loss of spinal motor neurons, for which no effective treatment exists. Epidermal growth factor (EGF) and growth hormone releasing peptide-6 (GHRP-6) have been considered as good candidates for the treatment of this disease, due to their well documented effects in eliciting pleiotrophic and cell survival mechanisms. The aim of the present work was to evaluate the separate and combined effects of both peptides in an experimental animal model of ALS, the proximal axonopathy induced by 1,2 diacetylbenzene (1,2 DAB) in mice. The evaluations were conducted by means of behavioral tests (trapeze, tail suspension, gait pattern, and open field) and by recording the complex muscle action potential (CMAP) in three different hind limb segments: proximal S1, medial S2, and distal S3. Intraperitoneal daily administration of 1,2 DAB produced significant reduction in body weight, muscle strength, extensor reflex, spontaneous activity, and changes in gait pattern parameters. In parallel 1,2 DAB produced significant prolongation of onset latency and decrease in amplitude of CMAP and in the integrated complex action potential index. Daily administration of the separate compounds did not accelerate the recovery of the affected parameters, except for the gait pattern. The combined treatment produced significant improvement in behavioral parameters, as well as in electrophysiological recovery, particularly in the proximal segment of CMAP. The latter results confirm the proximal character of 1,2 DAB neuropathy, and suggest that combined therapy with EGF and GHRP-6 might be a good therapeutic strategy for the treatment of ALS.
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Affiliation(s)
- Diana García Del Barco
- Center for Genetic Engineering and Biotechnology, Ave. 31 e/158 & 190, Cubanacan, Playa P.O. Box 6162, 10600 Havana, Cuba.
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Tabakoff B, Saba L, Printz M, Flodman P, Hodgkinson C, Goldman D, Koob G, Richardson HN, Kechris K, Bell RL, Hübner N, Heinig M, Pravenec M, Mangion J, Legault L, Dongier M, Conigrave KM, Whitfield JB, Saunders J, Grant B, Hoffman PL. Genetical genomic determinants of alcohol consumption in rats and humans. BMC Biol 2009; 7:70. [PMID: 19874574 PMCID: PMC2777866 DOI: 10.1186/1741-7007-7-70] [Citation(s) in RCA: 127] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2009] [Accepted: 10/27/2009] [Indexed: 01/22/2023] Open
Abstract
BACKGROUND We have used a genetical genomic approach, in conjunction with phenotypic analysis of alcohol consumption, to identify candidate genes that predispose to varying levels of alcohol intake by HXB/BXH recombinant inbred rat strains. In addition, in two populations of humans, we assessed genetic polymorphisms associated with alcohol consumption using a custom genotyping array for 1,350 single nucleotide polymorphisms (SNPs). Our goal was to ascertain whether our approach, which relies on statistical and informatics techniques, and non-human animal models of alcohol drinking behavior, could inform interpretation of genetic association studies with human populations. RESULTS In the HXB/BXH recombinant inbred (RI) rats, correlation analysis of brain gene expression levels with alcohol consumption in a two-bottle choice paradigm, and filtering based on behavioral and gene expression quantitative trait locus (QTL) analyses, generated a list of candidate genes. A literature-based, functional analysis of the interactions of the products of these candidate genes defined pathways linked to presynaptic GABA release, activation of dopamine neurons, and postsynaptic GABA receptor trafficking, in brain regions including the hypothalamus, ventral tegmentum and amygdala. The analysis also implicated energy metabolism and caloric intake control as potential influences on alcohol consumption by the recombinant inbred rats. In the human populations, polymorphisms in genes associated with GABA synthesis and GABA receptors, as well as genes related to dopaminergic transmission, were associated with alcohol consumption. CONCLUSION Our results emphasize the importance of the signaling pathways identified using the non-human animal models, rather than single gene products, in identifying factors responsible for complex traits such as alcohol consumption. The results suggest cross-species similarities in pathways that influence predisposition to consume alcohol by rats and humans. The importance of a well-defined phenotype is also illustrated. Our results also suggest that different genetic factors predispose alcohol dependence versus the phenotype of alcohol consumption.
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Affiliation(s)
- Boris Tabakoff
- Department of Pharmacology, University of Colorado, Denver, Aurora, CO, USA
| | - Laura Saba
- Department of Pharmacology, University of Colorado, Denver, Aurora, CO, USA
| | - Morton Printz
- Department of Pharmacology, University of California San Diego, La Jolla, CA, USA
| | - Pam Flodman
- Department of Pediatrics, University of California Irvine, Irvine, CA, USA
| | - Colin Hodgkinson
- Laboratory of Neurogenetics, National Institute on Alcohol Abuse and Alcoholism, Bethesda, MD, USA
| | - David Goldman
- Laboratory of Neurogenetics, National Institute on Alcohol Abuse and Alcoholism, Bethesda, MD, USA
| | - George Koob
- Committee on the Neurobiology of Addictive Disorders, The Scripps Research Institute, La Jolla, CA, USA
| | - Heather N Richardson
- Committee on the Neurobiology of Addictive Disorders, The Scripps Research Institute, La Jolla, CA, USA
- Department Psychology-Neuroscience, University of Massachusetts Amherst, Amherst, MA, USA
| | - Katerina Kechris
- Department of Biostatistics and Informatics, Colorado School of Public Health, University of Colorado Denver, Aurora, CO, USA
| | - Richard L Bell
- Institute of Psychiatric Research, Indiana University School of Medicine, Indianapolis, IN, USA
| | - Norbert Hübner
- Max Delbrück Center for Molecular Medicine, Berlin, Germany
| | | | - Michal Pravenec
- Institute of Physiology, Czech Academy of Sciences, Prague, Czech Republic
| | - Jonathan Mangion
- MRC Clinical Sciences Centre, London, UK
- Applied Biosystems, Lingley House, 120 Birchwood Blvd., Warrington, Cheshire, WA3 7QH, UK
| | - Lucie Legault
- Department of Psychiatry, McGill University, Montreal, Quebec, Canada
| | - Maurice Dongier
- Department of Psychiatry, McGill University, Montreal, Quebec, Canada
| | - Katherine M Conigrave
- Drug Health Services, Royal Prince Alfred Hospital, Sydney Medical School, University of Sydney, New South Wales, Australia
| | | | - John Saunders
- School of Medicine, University of Queensland, Brisbane, Queensland, Australia
| | - Bridget Grant
- Division of Epidemiology, National Institute on Alcohol Abuse and Alcoholism, Rockville, MD, USA
| | - Paula L Hoffman
- Department of Pharmacology, University of Colorado, Denver, Aurora, CO, USA
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Alberti C, Gonzalez J, Maldonado H, Medina F, Barriga A, García L, Kettlun A, Collados L, Puente J, Cartier L, Valenzuela M. Comparative study of CSF neurofilaments in HTLV-1-associated myelopathy/tropical spastic paraparesis and other neurological disorders. AIDS Res Hum Retroviruses 2009; 25:803-9. [PMID: 19678766 DOI: 10.1089/aid.2008.0262] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP) is a progressive CNS disease leading to corticospinal tract degeneration. Various degenerative diseases have increased neurofilament subunit concentration in cerebrospinal fluid (CSF), frequently showing hyperphosphorylation in neurofilaments. The aim of this study was to determine if there were elevated concentrations of neurofilament light subunit (NFL) and phosphorylated forms of neurofilament heavy subunit (PNFH) in HAM/TSP CSF. NF concentrations were compared with those of controls and patients with neurodegenerative diseases associated with other retroviruses (HIV-associated dementia, HAD) and a form of prion disease (familiar Creutzfeldt-Jakob, FCJD). Western blotting of CSF with antibodies against NFL showed two immunoreactive bands of 66 and 59 kDa, the latter probably corresponding to a partially degraded NFL form. The concentration of the 59-kDa form was not different in HAM/TSP compared with controls, but it was significantly increased in HAD and FCJD groups. ELISA assay for PNFH did not show differences among HAM/TSP, HAD, and control groups, while PNFH concentration was significantly elevated in FCJD. Our results show that CSF NFL and PNFH are not molecular markers of axonal damage for HAM/TSP probably due to the slow progression of this disease. NFL phosphorylation studies required previous immunoprecipitation from CSF for mass spectrometric analysis. This preliminary analysis indicated phosphorylation at S472 and at some other residues.
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Affiliation(s)
- Carolina Alberti
- Bioquimica y Biologia Molecular, Universidad de Chile, Santiago, Chile
| | - Juan Gonzalez
- Bioquimica y Biologia Molecular, Universidad de Chile, Santiago, Chile
| | - Horacio Maldonado
- Bioquimica y Biologia Molecular, Universidad de Chile, Santiago, Chile
| | - Fernando Medina
- Bioquimica y Biologia Molecular, Universidad de Chile, Santiago, Chile
| | - Andrés Barriga
- Bioquimica y Biologia Molecular, Universidad de Chile, Santiago, Chile
| | - Lorena García
- Bioquimica y Biologia Molecular, Universidad de Chile, Santiago, Chile
| | - Ana Kettlun
- Bioquimica y Biologia Molecular, Universidad de Chile, Santiago, Chile
| | - Lucía Collados
- Bioquimica y Biologia Molecular, Universidad de Chile, Santiago, Chile
| | - Javier Puente
- Bioquimica y Biologia Molecular, Universidad de Chile, Santiago, Chile
| | - Luis Cartier
- Ciencias Neurologicas, Universidad de Chile, Santiago, Chile
| | - Maria Valenzuela
- Bioquimica y Biologia Molecular, Universidad de Chile, Santiago, Chile
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Perrot R, Eyer J. Neuronal intermediate filaments and neurodegenerative disorders. Brain Res Bull 2009; 80:282-95. [PMID: 19539727 DOI: 10.1016/j.brainresbull.2009.06.004] [Citation(s) in RCA: 67] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2009] [Revised: 06/05/2009] [Accepted: 06/05/2009] [Indexed: 12/12/2022]
Abstract
Intermediate filaments represent the most abundant cytoskeletal element in mature neurons. Mutations and/or accumulations of neuronal intermediate filament proteins are frequently observed in several human neurodegenerative disorders. Although it is now admitted that disorganization of the neurofilament network may be directly involved in neurodegeneration, certain type of perikaryal intermediate filament aggregates confer protection in motor neuron disease. The use of various mouse models provided a better knowledge of the role played by the disorganization of intermediate filaments in the pathogenesis of neurodegenerative disorders, but the mechanisms leading to the formation of these aggregates remain elusive. Here, we will review some neurodegenerative diseases involving intermediate filaments abnormalities and possible mechanisms susceptible to provoke them.
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Affiliation(s)
- Rodolphe Perrot
- Department of Anatomy and Physiology of Laval University, Centre de Recherche du Centre Hospitalier Universitaire de Québec, Quebec, Canada
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Shea TB, Lee S, Kushkuley J, Dubey M, Chan WKH. Neurofilament dynamics: a tug of war by microtubule motors. FUTURE NEUROLOGY 2009. [DOI: 10.2217/fnl.09.4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Structural support for axons, which can consist of volumes thousands of times larger than the neuronal perikaryon, is provided in part by neurofilaments (NFs), the major fibrous constituent of the axonal cytoskeleton. Most NFs undergo anterograde transport (towards the synapse or growth cone), while a few undergo retrograde transport (back towards the perikaryon). Some NFs exhibit an extended residence time along axons, which allows NFs to provide structural support to the axon yet minimizes NF turnover, which would otherwise impart a prohibitive metabolic burden upon the neuron. Herein, we explore known and hypothesized roles for microtubule motors in transport and distribution of NFs along axons. We present evidence that those NFs that display extended residence along axons are critically dependent upon surrounding microtubules, and that simultaneous interaction with multiple microtubule motors provides the architectural force regulating their distribution.
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Affiliation(s)
- Thomas B Shea
- Center for Cellular Neurobiology & Neurodegeneration Research, Departments of Biological Sciences & Biochemistry, University of Massachusetts–Lowell, One University Avenue, Lowell, MA 01854, USA
| | - Sangmook Lee
- Center for Cellular Neurobiology & Neurodegeneration Research, Departments of Biological Sciences & Biochemistry, University of Massachusetts–Lowell, One University Avenue, Lowell, MA 01854, USA
| | - Jacob Kushkuley
- Center for Cellular Neurobiology & Neurodegeneration Research, Departments of Biological Sciences & Biochemistry, University of Massachusetts–Lowell, One University Avenue, Lowell, MA 01854, USA
| | - Maya Dubey
- Center for Cellular Neurobiology & Neurodegeneration Research, Departments of Biological Sciences & Biochemistry, University of Massachusetts–Lowell, One University Avenue, Lowell, MA 01854, USA
| | - Walter K-H Chan
- Center for Cellular Neurobiology & Neurodegeneration Research, Departments of Biological Sciences & Biochemistry, University of Massachusetts–Lowell, One University Avenue, Lowell, MA 01854, USA
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Shea TB, Chan WKH, Kushkuley J, Lee S. Organizational dynamics, functions, and pathobiological dysfunctions of neurofilaments. Results Probl Cell Differ 2009; 48:29-45. [PMID: 19554281 DOI: 10.1007/400_2009_8] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Neurofilament phosphorylation has long been considered to regulate their axonal transport rate, and in doing so it provides stability to mature axons. We evaluate the collective evidence to date regarding how neurofilament C-terminal phosphorylation may regulate axonal transport. We present a few suggestions for further experimentation in this area, and expand upon previous models for axonal NF dynamics. We present evidence that the NFs that display extended residence along axons are critically dependent upon the surrounding microtubules, and that simultaneous interaction with multiple microtubule motors provides the architectural force that regulates their distribution. Finally, we address how C-terminal phosphorylation is regionally and temporally regulated by a balance of kinase and phosphatase activities, and how misregulation of this balance might contribute to motor neuron disease.
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Affiliation(s)
- Thomas B Shea
- Departments of Biological Sciences and Biochemistry, Center for Cellular Neurobiology and Neurodegeneration Research, University of Massachusetts Lowell, One University Avenue, Lowell, MA 01854, England.
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Teuling E, van Dis V, Wulf PS, Haasdijk ED, Akhmanova A, Hoogenraad CC, Jaarsma D. A novel mouse model with impaired dynein/dynactin function develops amyotrophic lateral sclerosis (ALS)-like features in motor neurons and improves lifespan in SOD1-ALS mice. Hum Mol Genet 2008; 17:2849-62. [PMID: 18579581 DOI: 10.1093/hmg/ddn182] [Citation(s) in RCA: 62] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative condition characterized by progressive motor neuron degeneration and muscle paralysis. Genetic evidence from man and mouse has indicated that mutations in the dynein/dynactin motor complex are correlated with motor neuron degeneration. In this study, we have generated transgenic mice with neuron-specific expression of Bicaudal D2 N-terminus (BICD2-N) to chronically impair dynein/dynactin function. Motor neurons expressing BICD2-N showed accumulation of dynein and dynactin in the cell body, Golgi fragmentation and several signs of impaired retrograde trafficking: the appearance of giant neurofilament swellings in the proximal axon, reduced retrograde labelling by tracer injected in the muscle and delayed expression of the injury transcription factor ATF3 after axon transection. Despite these abnormalities, BICD2-N mice did not develop signs of motor neuron degeneration and motor abnormalities. Interestingly, the BICD2-N transgene increased lifespan in 'low copy' SOD1-G93A ALS transgenic mice. Our findings indicate that impaired dynein/dynactin function can explain several pathological features observed in ALS patients, but may be beneficial in some forms of ALS.
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Affiliation(s)
- Eva Teuling
- Department of Neuroscience, Erasmus MC, PO Box 2040, 3000CA Rotterdam, The Netherlands
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