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Nefedova VV, Kleymenov SY, Safenkova IV, Levitsky DI, Matyushenko AM. Neurofilament Light Protein Rod Domain Exhibits Structural Heterogeneity. Biomolecules 2024; 14:85. [PMID: 38254685 PMCID: PMC10813002 DOI: 10.3390/biom14010085] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2023] [Revised: 12/23/2023] [Accepted: 01/06/2024] [Indexed: 01/24/2024] Open
Abstract
Neurofilaments are neuron-specific proteins that belong to the intermediate filament (IFs) protein family, with the neurofilament light chain protein (NFL) being the most abundant. The IFs structure typically includes a central coiled-coil rod domain comprised of coils 1A, 1B, and 2, separated by linker regions. The thermal stability of the IF molecule plays a crucial role in its ability for self-association. In the current study, we investigated the thermal stability of NFL coiled-coil domains by analyzing a set of recombinant domains and their fusions (NFL1B, NFL1A+1B, NFL2, NFL1B+2, and NFLROD) via circular dichroism spectroscopy and differential scanning calorimetry. The thermal stability of coiled-coil domains is evident in a wide range of temperatures, and thermal transition values (Tm) correspond well between isolated coiled-coil domains and full-length NFL. NFL1B has a Tm of 39.4 °C, and its' fusions, NFL1A+1B and NFL1B+2, have a Tm of 41.9 °C and 41.5 °C, respectively. However, in the case of NFL2, thermal denaturation includes at least two thermal transitions at 37.2 °C and 62.7 °C. These data indicate that the continuous α-helical structure of the coil 2 domain has parts with varied thermal stability. Among all the NFL fragments, only NFL2 underwent irreversible heat-induced denaturation. Together, these results unveil the origin of full-length NFL's thermal transitions, and reveal its domains structure and properties.
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Affiliation(s)
- Victoria V. Nefedova
- Research Centre of Biotechnology, Russian Academy of Sciences, 119071 Moscow, Russia; (S.Y.K.); (I.V.S.); (D.I.L.); (A.M.M.)
| | - Sergey Y. Kleymenov
- Research Centre of Biotechnology, Russian Academy of Sciences, 119071 Moscow, Russia; (S.Y.K.); (I.V.S.); (D.I.L.); (A.M.M.)
- Koltzov Institute of Developmental Biology, Russian Academy of Sciences, 119334 Moscow, Russia
| | - Irina V. Safenkova
- Research Centre of Biotechnology, Russian Academy of Sciences, 119071 Moscow, Russia; (S.Y.K.); (I.V.S.); (D.I.L.); (A.M.M.)
| | - Dmitrii I. Levitsky
- Research Centre of Biotechnology, Russian Academy of Sciences, 119071 Moscow, Russia; (S.Y.K.); (I.V.S.); (D.I.L.); (A.M.M.)
| | - Alexander M. Matyushenko
- Research Centre of Biotechnology, Russian Academy of Sciences, 119071 Moscow, Russia; (S.Y.K.); (I.V.S.); (D.I.L.); (A.M.M.)
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2
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Kotaich F, Caillol D, Bomont P. Neurofilaments in health and Charcot-Marie-Tooth disease. Front Cell Dev Biol 2023; 11:1275155. [PMID: 38164457 PMCID: PMC10758125 DOI: 10.3389/fcell.2023.1275155] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2023] [Accepted: 10/02/2023] [Indexed: 01/03/2024] Open
Abstract
Neurofilaments (NFs) are the most abundant component of mature neurons, that interconnect with actin and microtubules to form the cytoskeleton. Specifically expressed in the nervous system, NFs present the particularity within the Intermediate Filament family of being formed by four subunits, the neurofilament light (NF-L), medium (NF-M), heavy (NF-H) proteins and α-internexin or peripherin. Here, we review the current knowledge on NF proteins and neurofilaments, from their domain structures and their model of assembly to the dynamics of their transport and degradation along the axon. The formation of the filament and its behaviour are regulated by various determinants, including post-transcriptional (miRNA and RBP proteins) and post-translational (phosphorylation and ubiquitination) modifiers. Altogether, the complex set of modifications enable the neuron to establish a stable but elastic NF array constituting the structural scaffold of the axon, while permitting the local expression of NF proteins and providing the dynamics necessary to fulfil local demands and respond to stimuli and injury. Thus, in addition to their roles in mechano-resistance, radial axonal outgrowth and nerve conduction, NFs control microtubule dynamics, organelle distribution and neurotransmission at the synapse. We discuss how the studies of neurodegenerative diseases with NF aggregation shed light on the biology of NFs. In particular, the NEFL and NEFH genes are mutated in Charcot-Marie-Tooth (CMT) disease, the most common inherited neurological disorder of the peripheral nervous system. The clinical features of the CMT forms (axonal CMT2E, CMT2CC; demyelinating CMT1F; intermediate I-CMT) with symptoms affecting the central nervous system (CNS) will allow us to further investigate the physiological roles of NFs in the brain. Thus, NF-CMT mouse models exhibit various degrees of sensory-motor deficits associated with CNS symptoms. Cellular systems brought findings regarding the dominant effect of NF-L mutants on NF aggregation and transport, although these have been recently challenged. Neurofilament detection without NF-L in recessive CMT is puzzling, calling for a re-examination of the current model in which NF-L is indispensable for NF assembly. Overall, we discuss how the fundamental and translational fields are feeding each-other to increase but also challenge our knowledge of NF biology, and to develop therapeutic avenues for CMT and neurodegenerative diseases with NF aggregation.
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Affiliation(s)
| | | | - Pascale Bomont
- ERC team, NeuroMyoGene Institute-Pathophysiology and Genetics of Neuron and Muscle, Inserm U1315, CNRS UMR5261, University of Lyon 1, Lyon, France
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3
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Nasr-Eldin YK, Cartwright MS, Hamed A, Ali LH, Abdel-Nasser AM. Exploration of Neurofilament Light Chain and Nerve Ultrasound in Leprotic Neuropathy. JOURNAL OF ULTRASOUND IN MEDICINE : OFFICIAL JOURNAL OF THE AMERICAN INSTITUTE OF ULTRASOUND IN MEDICINE 2023; 42:2803-2813. [PMID: 37661825 DOI: 10.1002/jum.16319] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/14/2023] [Revised: 07/26/2023] [Accepted: 08/06/2023] [Indexed: 09/05/2023]
Abstract
OBJECTIVES To explore neurofilament light chain (NfL) levels in leprotic neuropathy compared to controls, and to determine if the changes correlate with ultrasonographic nerve findings. METHODS Individuals with leprosy with signs or symptoms suggestive of peripheral nerve involvement were recruited. They were evaluated by clinical examination, functional scores, laboratory assessments (including NfL), nerve conduction studies (NCS), and ultrasound. Ultrasound was conducted in bilateral median, ulnar, tibial, fibular, sural, and vagus nerves as well as cervical roots 5 and 6. Results were compared to age, sex, and body mass index matched healthy controls. RESULTS A total of 320 nerves from 20 patients and 480 nerves from 30 controls were evaluated. NfL was significantly elevated in those with leprosy with a mean and standard deviation of 7.50 + 2.83 compared with 3.42 + 1.18 in controls (P < .001). Ultrasound showed focal enlargement of the nerves, particularly at entrapment sites. Additionally, there were noticeable changes in neural Doppler signal, echogenicity, and epineural thickness among the measured nerve sites. NfL levels in those with leprosy correlated closely with nerve cross-sectional area at all sites (P < .05). Functional and clinical assessment scores correlated with NfL and sonographic cross-sectional area as well (P ≤ .05). CONCLUSIONS NfL is elevated in leprotic neuropathy. Ultrasound showed specific morphological changes in individuals with leprosy, and nerve enlargement correlated with NfL levels. Thus, both modalities may be useful for the diagnosis, prognosis, and disease monitoring in those with leprotic neuropathy, and further investigations are warranted.
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Affiliation(s)
| | - Michael S Cartwright
- Neurology Department, Wake Forest University School of Medicine, Winston-Salem, North Carolina, USA
| | - Ahmed Hamed
- Rheumatology and Rehabilitation Department, Minia University, Minia, Egypt
| | - Lamia Hamdy Ali
- Clinical Pathology Department, Minia University, Minia, Egypt
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Huynh DT, Tsolova KN, Watson AJ, Khal SK, Green JR, Li D, Hu J, Soderblom EJ, Chi JT, Evans CS, Boyce M. O-GlcNAcylation regulates neurofilament-light assembly and function and is perturbed by Charcot-Marie-Tooth disease mutations. Nat Commun 2023; 14:6558. [PMID: 37848414 PMCID: PMC10582078 DOI: 10.1038/s41467-023-42227-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2023] [Accepted: 10/02/2023] [Indexed: 10/19/2023] Open
Abstract
The neurofilament (NF) cytoskeleton is critical for neuronal morphology and function. In particular, the neurofilament-light (NF-L) subunit is required for NF assembly in vivo and is mutated in subtypes of Charcot-Marie-Tooth (CMT) disease. NFs are highly dynamic, and the regulation of NF assembly state is incompletely understood. Here, we demonstrate that human NF-L is modified in a nutrient-sensitive manner by O-linked-β-N-acetylglucosamine (O-GlcNAc), a ubiquitous form of intracellular glycosylation. We identify five NF-L O-GlcNAc sites and show that they regulate NF assembly state. NF-L engages in O-GlcNAc-mediated protein-protein interactions with itself and with the NF component α-internexin, implying that O-GlcNAc may be a general regulator of NF architecture. We further show that NF-L O-GlcNAcylation is required for normal organelle trafficking in primary neurons. Finally, several CMT-causative NF-L mutants exhibit perturbed O-GlcNAc levels and resist the effects of O-GlcNAcylation on NF assembly state, suggesting a potential link between dysregulated O-GlcNAcylation and pathological NF aggregation. Our results demonstrate that site-specific glycosylation regulates NF-L assembly and function, and aberrant NF O-GlcNAcylation may contribute to CMT and other neurodegenerative disorders.
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Affiliation(s)
- Duc T Huynh
- Department of Biochemistry, Duke University School of Medicine, Durham, NC, 27710, USA
| | - Kalina N Tsolova
- Department of Biochemistry, Duke University School of Medicine, Durham, NC, 27710, USA
| | - Abigail J Watson
- Department of Biochemistry, Duke University School of Medicine, Durham, NC, 27710, USA
| | - Sai Kwan Khal
- Department of Biochemistry, Duke University School of Medicine, Durham, NC, 27710, USA
| | - Jordan R Green
- Department of Cell Biology, Duke University School of Medicine, Durham, NC, 27710, USA
| | - Di Li
- Department of Biochemistry, Duke University School of Medicine, Durham, NC, 27710, USA
| | - Jimin Hu
- Department of Biochemistry, Duke University School of Medicine, Durham, NC, 27710, USA
| | - Erik J Soderblom
- Proteomics and Metabolomics Shared Resource, Duke University School of Medicine, Durham, NC, 27710, USA
| | - Jen-Tsan Chi
- Department of Molecular Genetics and Microbiology, Duke University School of Medicine, Durham, NC, 27710, USA
| | - Chantell S Evans
- Department of Cell Biology, Duke University School of Medicine, Durham, NC, 27710, USA
| | - Michael Boyce
- Department of Biochemistry, Duke University School of Medicine, Durham, NC, 27710, USA.
- Department of Cell Biology, Duke University School of Medicine, Durham, NC, 27710, USA.
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5
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Abstract
Neurons are markedly compartmentalized, which makes them reliant on axonal transport to maintain their health. Axonal transport is important for anterograde delivery of newly synthesized macromolecules and organelles from the cell body to the synapse and for the retrograde delivery of signaling endosomes and autophagosomes for degradation. Dysregulation of axonal transport occurs early in neurodegenerative diseases and plays a key role in axonal degeneration. Here, we provide an overview of mechanisms for regulation of axonal transport; discuss how these mechanisms are disrupted in neurodegenerative diseases including Alzheimer's disease, Parkinson's disease, Huntington's disease, hereditary spastic paraplegia, amyotrophic lateral sclerosis, and Charcot-Marie-Tooth disease; and discuss therapeutic approaches targeting axonal transport.
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6
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Uchida A, Peng J, Brown A. Regulation of neurofilament length and transport by a dynamic cycle of phospho-dependent polymer severing and annealing. Mol Biol Cell 2023; 34:ar68. [PMID: 36989035 PMCID: PMC10295484 DOI: 10.1091/mbc.e23-01-0024] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2023] [Revised: 03/17/2023] [Accepted: 03/22/2023] [Indexed: 03/30/2023] Open
Abstract
Neurofilaments are cargoes of axonal transport which are unique among known intracellular cargoes in that they are long, flexible protein polymers. These polymers are transported into axons, where they accumulate in large numbers to drive the expansion of axon caliber, which is an important determinant of axonal conduction velocity. We reported previously that neurofilaments can be lengthened by joining ends, called end-to-end annealing, and that they can be shortened by severing. Here, we show that neurofilament annealing and severing are robust and quantifiable phenomena in cultured neurons that act antagonistically to regulate neurofilament length. We show that this in turn regulates neurofilament transport and that severing is regulated by N-terminal phosphorylation of the neurofilament subunit proteins. We propose that focal destabilization of intermediate filaments by site-directed phosphorylation may be a general enzymatic mechanism for severing these cytoskeletal polymers, providing a mechanism to regulate the transport and accumulation of neurofilaments in axons.
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Affiliation(s)
- Atsuko Uchida
- Department of Neuroscience, Ohio State University, Columbus, OH 43210
| | - Juan Peng
- Center for Biostatistics and Department of Biomedical Informatics, Ohio State University, Columbus, OH 43210
| | - Anthony Brown
- Department of Neuroscience, Ohio State University, Columbus, OH 43210
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7
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Huynh DT, Hu J, Schneider JR, Tsolova KN, Soderblom EJ, Watson AJ, Chi JT, Evans CS, Boyce M. O-GlcNAcylation regulates neurofilament-light assembly and function and is perturbed by Charcot-Marie-Tooth disease mutations. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.02.22.529563. [PMID: 36865196 PMCID: PMC9980138 DOI: 10.1101/2023.02.22.529563] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/24/2023]
Abstract
The neurofilament (NF) cytoskeleton is critical for neuronal morphology and function. In particular, the neurofilament-light (NF-L) subunit is required for NF assembly in vivo and is mutated in subtypes of Charcot-Marie-Tooth (CMT) disease. NFs are highly dynamic, and the regulation of NF assembly state is incompletely understood. Here, we demonstrate that human NF-L is modified in a nutrient-sensitive manner by O-linked-β-N-acetylglucosamine (O-GlcNAc), a ubiquitous form of intracellular glycosylation. We identify five NF-L O-GlcNAc sites and show that they regulate NF assembly state. Interestingly, NF-L engages in O-GlcNAc-mediated protein-protein interactions with itself and with the NF component α-internexin, implying that O-GlcNAc is a general regulator of NF architecture. We further show that NF-L O-GlcNAcylation is required for normal organelle trafficking in primary neurons, underlining its functional significance. Finally, several CMT-causative NF-L mutants exhibit perturbed O-GlcNAc levels and resist the effects of O-GlcNAcylation on NF assembly state, indicating a potential link between dysregulated O-GlcNAcylation and pathological NF aggregation. Our results demonstrate that site-specific glycosylation regulates NF-L assembly and function, and aberrant NF O-GlcNAcylation may contribute to CMT and other neurodegenerative disorders.
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Affiliation(s)
- Duc T. Huynh
- Department of Biochemistry, Duke University School of Medicine, Durham, NC 27710, USA
| | - Jimin Hu
- Department of Biochemistry, Duke University School of Medicine, Durham, NC 27710, USA
| | - Jordan R. Schneider
- Department of Cell Biology, Duke University School of Medicine, Durham, NC 27710, USA
| | - Kalina N. Tsolova
- Department of Biochemistry, Duke University School of Medicine, Durham, NC 27710, USA
| | - Erik J. Soderblom
- Proteomics and Metabolomics Shared Resource, Duke University School of Medicine, Durham, NC 27710, USA
| | - Abigail J. Watson
- Department of Biochemistry, Duke University School of Medicine, Durham, NC 27710, USA
| | - Jen-Tsan Chi
- Department of Cell Biology, Duke University School of Medicine, Durham, NC 27710, USA
- Department of Molecular Genetics and Microbiology, Duke University School of Medicine, Durham, NC 27710, USA
| | - Chantell S. Evans
- Department of Cell Biology, Duke University School of Medicine, Durham, NC 27710, USA
| | - Michael Boyce
- Department of Biochemistry, Duke University School of Medicine, Durham, NC 27710, USA
- Department of Cell Biology, Duke University School of Medicine, Durham, NC 27710, USA
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8
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Mages B, Fuhs T, Aleithe S, Blietz A, Hobusch C, Härtig W, Schob S, Krueger M, Michalski D. The Cytoskeletal Elements MAP2 and NF-L Show Substantial Alterations in Different Stroke Models While Elevated Serum Levels Highlight Especially MAP2 as a Sensitive Biomarker in Stroke Patients. Mol Neurobiol 2021; 58:4051-4069. [PMID: 33931805 PMCID: PMC8280005 DOI: 10.1007/s12035-021-02372-3] [Citation(s) in RCA: 20] [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: 01/05/2021] [Accepted: 03/22/2021] [Indexed: 02/07/2023]
Abstract
In the setting of ischemic stroke, the neurofilament subunit NF-L and the microtubule-associated protein MAP2 have proven to be exceptionally ischemia-sensitive elements of the neuronal cytoskeleton. Since alterations of the cytoskeleton have been linked to the transition from reversible to irreversible tissue damage, the present study investigates underlying time- and region-specific alterations of NF-L and MAP2 in different animal models of focal cerebral ischemia. Although NF-L is increasingly established as a clinical stroke biomarker, MAP2 serum measurements after stroke are still lacking. Therefore, the present study further compares serum levels of MAP2 with NF-L in stroke patients. In the applied animal models, MAP2-related immunofluorescence intensities were decreased in ischemic areas, whereas the abundance of NF-L degradation products accounted for an increase of NF-L-related immunofluorescence intensity. Accordingly, Western blot analyses of ischemic areas revealed decreased protein levels of both MAP2 and NF-L. The cytoskeletal alterations are further reflected at an ultrastructural level as indicated by a significant reduction of detectable neurofilaments in cortical axons of ischemia-affected areas. Moreover, atomic force microscopy measurements confirmed altered mechanical properties as indicated by a decreased elastic strength in ischemia-affected tissue. In addition to the results from the animal models, stroke patients exhibited significantly elevated serum levels of MAP2, which increased with infarct size, whereas serum levels of NF-L did not differ significantly. Thus, MAP2 appears to be a more sensitive stroke biomarker than NF-L, especially for early neuronal damage. This perspective is strengthened by the results from the animal models, showing MAP2-related alterations at earlier time points compared to NF-L. The profound ischemia-induced alterations further qualify both cytoskeletal elements as promising targets for neuroprotective therapies.
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Affiliation(s)
- Bianca Mages
- Institute of Anatomy, Leipzig University, Leipzig, Germany.
| | - Thomas Fuhs
- Section of Soft Matter Physics, Faculty of Physics and Geosciences, Leipzig University, Leipzig, Germany
| | - Susanne Aleithe
- Department of Neurology, Leipzig University, Leipzig, Germany
| | | | | | - Wolfgang Härtig
- Paul Flechsig Institute of Brain Research, Leipzig University, Leipzig, Germany
| | - Stefan Schob
- Department of Neuroradiology, Leipzig University, Leipzig, Germany
| | - Martin Krueger
- Institute of Anatomy, Leipzig University, Leipzig, Germany
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9
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Atkinson R, Leung J, Bender J, Kirkcaldie M, Vickers J, King A. TDP-43 mislocalization drives neurofilament changes in a novel model of TDP-43 proteinopathy. Dis Model Mech 2021; 14:dmm.047548. [PMID: 33408125 PMCID: PMC7888715 DOI: 10.1242/dmm.047548] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2020] [Accepted: 12/17/2020] [Indexed: 12/21/2022] Open
Abstract
Mislocalization of the TAR DNA-binding protein 43 (TDP-43) from the nucleus to the cytoplasm is a common feature of neurodegenerative conditions such as amyotrophic lateral sclerosis (ALS) and frontotemporal lobar degeneration (FTLD). The downstream in vivo cellular effects of this mislocalization are not well understood. To investigate the impact of mislocalized TDP-43 on neuronal cell bodies, axons and axonal terminals, we utilized the mouse visual system to create a new model of TDP-43 proteinopathy. Mouse (C57BL/6J) retinal ganglion cells (RGCs) were transduced with GFP-tagged human wildtype TDP-43 (hTDP-WT-GFP) and human TDP-43 with a mutation in the nuclear localization sequence (hTDP-ΔNLS-GFP), to cause TDP-43 mislocalization, with ∼60% transduction efficiency achieved. Expression of both hTDP-WT-GFP and hTDP-ΔNLS-GFP resulted in changes to neurofilament expression, with cytoplasmic TDP-43 being associated with significantly (p<0.05) increased neurofilament heavy expression in the cell soma, and both forms of altered TDP-43 leading to significantly (p<0.05) decreased numbers of neurofilament-positive axons within the optic nerve. Alterations to neurofilament proteins were associated with significantly (p<0.05) increased microglial density in the optic nerve and retina. Furthermore expression of hTDP-WT-GFP was associated with a significant (p<0.05) increase in pre-synaptic input into RGCs in the retina. The current study has developed a new model allowing detailed examination of alterations to TDP-43 and will contribute to the knowledge of TDP-43-mediated neuronal alterations and degeneration.
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Affiliation(s)
- Rachel Atkinson
- Wicking Dementia Research and Education Centre, University of Tasmania, Medical Science Precinct, 17, Liverpool Street, Hobart, Tasmania, Australia 7000, Australia
| | - Jacqueline Leung
- Wicking Dementia Research and Education Centre, University of Tasmania, Medical Science Precinct, 17, Liverpool Street, Hobart, Tasmania, Australia 7000, Australia
| | - James Bender
- Wicking Dementia Research and Education Centre, University of Tasmania, Medical Science Precinct, 17, Liverpool Street, Hobart, Tasmania, Australia 7000, Australia
| | - Matthew Kirkcaldie
- Wicking Dementia Research and Education Centre, University of Tasmania, Medical Science Precinct, 17, Liverpool Street, Hobart, Tasmania, Australia 7000, Australia
| | - James Vickers
- Wicking Dementia Research and Education Centre, University of Tasmania, Medical Science Precinct, 17, Liverpool Street, Hobart, Tasmania, Australia 7000, Australia
| | - Anna King
- Wicking Dementia Research and Education Centre, University of Tasmania, Medical Science Precinct, 17, Liverpool Street, Hobart, Tasmania, Australia 7000, Australia
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10
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Guillaud L, El-Agamy SE, Otsuki M, Terenzio M. Anterograde Axonal Transport in Neuronal Homeostasis and Disease. Front Mol Neurosci 2020; 13:556175. [PMID: 33071754 PMCID: PMC7531239 DOI: 10.3389/fnmol.2020.556175] [Citation(s) in RCA: 46] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2020] [Accepted: 08/26/2020] [Indexed: 12/12/2022] Open
Abstract
Neurons are highly polarized cells with an elongated axon that extends far away from the cell body. To maintain their homeostasis, neurons rely extensively on axonal transport of membranous organelles and other molecular complexes. Axonal transport allows for spatio-temporal activation and modulation of numerous molecular cascades, thus playing a central role in the establishment of neuronal polarity, axonal growth and stabilization, and synapses formation. Anterograde and retrograde axonal transport are supported by various molecular motors, such as kinesins and dynein, and a complex microtubule network. In this review article, we will primarily discuss the molecular mechanisms underlying anterograde axonal transport and its role in neuronal development and maturation, including the establishment of functional synaptic connections. We will then provide an overview of the molecular and cellular perturbations that affect axonal transport and are often associated with axonal degeneration. Lastly, we will relate our current understanding of the role of axonal trafficking concerning anterograde trafficking of mRNA and its involvement in the maintenance of the axonal compartment and disease.
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Affiliation(s)
- Laurent Guillaud
- Molecular Neuroscience Unit, Okinawa Institute of Science and Technology Graduate University, Okinawa, Japan
| | - Sara Emad El-Agamy
- Molecular Neuroscience Unit, Okinawa Institute of Science and Technology Graduate University, Okinawa, Japan
| | - Miki Otsuki
- Molecular Neuroscience Unit, Okinawa Institute of Science and Technology Graduate University, Okinawa, Japan
| | - Marco Terenzio
- Molecular Neuroscience Unit, Okinawa Institute of Science and Technology Graduate University, Okinawa, Japan
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11
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Beijer D, Sisto A, Van Lent J, Baets J, Timmerman V. Defects in Axonal Transport in Inherited Neuropathies. J Neuromuscul Dis 2020; 6:401-419. [PMID: 31561383 PMCID: PMC6918914 DOI: 10.3233/jnd-190427] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Axonal transport is a highly complex process essential for sustaining proper neuronal functioning. Disturbances can result in an altered neuronal homeostasis, aggregation of cargoes, and ultimately a dying-back degeneration of neurons. The impact of dysfunction in axonal transport is shown by genetic defects in key proteins causing a broad spectrum of neurodegenerative diseases, including inherited peripheral neuropathies. In this review, we provide an overview of the cytoskeletal components, molecular motors and adaptor proteins involved in axonal transport mechanisms and their implication in neuronal functioning. In addition, we discuss the involvement of axonal transport dysfunction in neurodegenerative diseases with a particular focus on inherited peripheral neuropathies. Lastly, we address some recent scientific advances most notably in therapeutic strategies employed in the area of axonal transport, patient-derived iPSC models, in vivo animal models, antisense-oligonucleotide treatments, and novel chemical compounds.
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Affiliation(s)
- Danique Beijer
- Neurogenetics Research Group, Department of Medical Sciences, University of Antwerp, Antwerpen, Belgium.,Neurogenetics Laboratory, Institute Born Bunge, Antwerpen, Belgium
| | - Angela Sisto
- Peripheral Neuropathy Research Group, Department of Biomedical Sciences, University of Antwerp, Antwerpen, Belgium.,Neurogenetics Laboratory, Institute Born Bunge, Antwerpen, Belgium
| | - Jonas Van Lent
- Peripheral Neuropathy Research Group, Department of Biomedical Sciences, University of Antwerp, Antwerpen, Belgium.,Neurogenetics Laboratory, Institute Born Bunge, Antwerpen, Belgium
| | - Jonathan Baets
- Neurogenetics Research Group, Department of Medical Sciences, University of Antwerp, Antwerpen, Belgium.,Neurogenetics Laboratory, Institute Born Bunge, Antwerpen, Belgium.,Neurology Department, University Hospital Antwerp, Antwerpen, Belgium
| | - Vincent Timmerman
- Peripheral Neuropathy Research Group, Department of Biomedical Sciences, University of Antwerp, Antwerpen, Belgium.,Neurogenetics Laboratory, Institute Born Bunge, Antwerpen, Belgium
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12
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Lambertsen KL, Soares CB, Gaist D, Nielsen HH. Neurofilaments: The C-Reactive Protein of Neurology. Brain Sci 2020; 10:brainsci10010056. [PMID: 31963750 PMCID: PMC7016784 DOI: 10.3390/brainsci10010056] [Citation(s) in RCA: 42] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2019] [Revised: 01/14/2020] [Accepted: 01/16/2020] [Indexed: 12/12/2022] Open
Abstract
Neurofilaments (NFs) are quickly becoming the biomarkers of choice in the field of neurology, suggesting their use as an unspecific screening marker, much like the use of elevated plasma C-reactive protein (CRP) in other fields. With sensitive techniques being readily available, evidence is growing regarding the diagnostic and prognostic value of NFs in many neurological disorders. Here, we review the latest literature on the structure and function of NFs and report the strengths and pitfalls of NFs as markers of neurodegeneration in the context of neurological diseases of the central and peripheral nervous systems.
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Affiliation(s)
- Kate L. Lambertsen
- Department of Neurology, Odense University Hospital, J.B. Winsloewsvej 4, 5000 Odense C, Denmark; (K.L.L.); (C.B.S.); (D.G.)
- Department of Neurobiology Research, Institute of Molecular Medicine, University of Southern Denmark, J.B. Winsloewsvej 21, st, 5000 Odense C, Denmark
- BRIDGE—Brain Research—Inter Disciplinary Guided Excellence, Department of Clinical Research, University of Southern Denmark, J.B. Winsloewsvej 19, 3. sal, 5000 Odense C, Denmark
| | - Catarina B. Soares
- Department of Neurology, Odense University Hospital, J.B. Winsloewsvej 4, 5000 Odense C, Denmark; (K.L.L.); (C.B.S.); (D.G.)
- Department of Neurobiology Research, Institute of Molecular Medicine, University of Southern Denmark, J.B. Winsloewsvej 21, st, 5000 Odense C, Denmark
| | - David Gaist
- Department of Neurology, Odense University Hospital, J.B. Winsloewsvej 4, 5000 Odense C, Denmark; (K.L.L.); (C.B.S.); (D.G.)
- BRIDGE—Brain Research—Inter Disciplinary Guided Excellence, Department of Clinical Research, University of Southern Denmark, J.B. Winsloewsvej 19, 3. sal, 5000 Odense C, Denmark
- Department of Clinical Research, Neurology Research Unit, Faculty of Health Sciences, University of Southern Denmark, Campusvej 55, 5230 Odense, Denmark
| | - Helle H. Nielsen
- Department of Neurology, Odense University Hospital, J.B. Winsloewsvej 4, 5000 Odense C, Denmark; (K.L.L.); (C.B.S.); (D.G.)
- Department of Neurobiology Research, Institute of Molecular Medicine, University of Southern Denmark, J.B. Winsloewsvej 21, st, 5000 Odense C, Denmark
- BRIDGE—Brain Research—Inter Disciplinary Guided Excellence, Department of Clinical Research, University of Southern Denmark, J.B. Winsloewsvej 19, 3. sal, 5000 Odense C, Denmark
- Department of Clinical Research, Neurology Research Unit, Faculty of Health Sciences, University of Southern Denmark, Campusvej 55, 5230 Odense, Denmark
- Correspondence:
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13
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Stone EJ, Uchida A, Brown A. Charcot-Marie-Tooth disease Type 2E/1F mutant neurofilament proteins assemble into neurofilaments. Cytoskeleton (Hoboken) 2019; 76:423-439. [PMID: 31574566 DOI: 10.1002/cm.21566] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2019] [Revised: 08/30/2019] [Accepted: 09/13/2019] [Indexed: 11/12/2022]
Abstract
Charcot-Marie-Tooth disease Type 2E/1F (CMT2E/1F) is a peripheral neuropathy caused by mutations in neurofilament protein L (NFL), which is one of five neurofilament subunit proteins that co-assemble to form neurofilaments in vivo. Prior studies on cultured cells have shown that CMT2E/1F mutations disrupt neurofilament assembly and lead to protein aggregation, suggesting a possible disease mechanism. However, electron microscopy of axons in peripheral nerve biopsies from patients has revealed accumulations of neurofilament polymers of normal appearance and no evidence of protein aggregates. To reconcile these observations, we reexamined the assembly of seven CMT2E/1F NFL mutants in cultured cells. None of the mutants assembled into homopolymers in SW13vim- cells, but P8R, P22S, L268/269P, and P440/441L mutant NFL assembled into heteropolymers in the presence of neurofilament protein M (NFM) alone, and N98S, Q332/333P, and E396/397K mutant NFL assembled in the presence of NFM and peripherin. P8R, P22S, N98S, L268/269P, E396/397K, and P440/441L mutant NFL co-assembled into neurofilaments with endogenous NFL, NFM, and α-internexin in cultured neurons, although the N98S and E396/397K mutants showed reduced filament incorporation, and the Q332/333P mutant showed limited incorporation. We conclude that all the mutants are capable of assembling into neurofilaments, but for some of the mutants this was dependent on the identity of the other neurofilament proteins available for co-assembly, and most likely also their relative expression level. Thus, caution should be exercised when drawing conclusions about the assembly capacity of CMT2E/1F mutants based on transient transfections in cultured cells.
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Affiliation(s)
- Elizabeth J Stone
- Department of Neuroscience, Ohio State University, Columbus, Ohio.,Neuroscience Graduate Program, Ohio State University, Columbus, Ohio
| | - Atsuko Uchida
- Department of Neuroscience, Ohio State University, Columbus, Ohio
| | - Anthony Brown
- Department of Neuroscience, Ohio State University, Columbus, Ohio
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14
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Didonna A, Opal P. The role of neurofilament aggregation in neurodegeneration: lessons from rare inherited neurological disorders. Mol Neurodegener 2019; 14:19. [PMID: 31097008 PMCID: PMC6524292 DOI: 10.1186/s13024-019-0318-4] [Citation(s) in RCA: 72] [Impact Index Per Article: 14.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2018] [Accepted: 04/26/2019] [Indexed: 12/13/2022] Open
Abstract
Many neurodegenerative disorders, including Parkinson's, Alzheimer's, and amyotrophic lateral sclerosis, are well known to involve the accumulation of disease-specific proteins. Less well known are the accumulations of another set of proteins, neuronal intermediate filaments (NFs), which have been observed in these diseases for decades. NFs belong to the family of cytoskeletal intermediate filament proteins (IFs) that give cells their shape; they determine axonal caliber, which controls signal conduction; and they regulate the transport of synaptic vesicles and modulate synaptic plasticity by binding to neurotransmitter receptors. In the last two decades, a number of rare disorders caused by mutations in genes that encode NFs or regulate their metabolism have been discovered. These less prevalent disorders are providing novel insights into the role of NF aggregation in the more common neurological disorders.
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Affiliation(s)
- Alessandro Didonna
- Department of Neurology and Weill Institute for Neurosciences, University of California at San Francisco, San Francisco, CA, 94158, USA
| | - Puneet Opal
- Davee Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, IL, 60611, USA. .,Department of Cell and Molecular Biology, Northwestern University Feinberg School of Medicine, Chicago, IL, 60611, USA.
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15
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Iverson GL, Reddi PJ, Posti JP, Kotilainen AK, Tenovuo O, Öhman J, Zetterberg H, Blennow K, Luoto TM. Serum Neurofilament Light Is Elevated Differentially in Older Adults with Uncomplicated Mild Traumatic Brain Injuries. J Neurotrauma 2019; 36:2400-2406. [PMID: 30843469 DOI: 10.1089/neu.2018.6341] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
Neurofilament light (NF-L) might have diagnostic and prognostic potential as a blood biomarker for mild traumatic brain injury (mTBI). However, elevated NF-L is associated with several neurological disorders associated with older age, which could confound its usefulness as a traumatic brain injury biomarker. We examined whether NF-L is elevated differentially following uncomplicated mTBI in older adults with pre-injury neurological disorders. In a case-control study, a sample of 118 adults (mean age = 62.3 years, standard deviation [SD] = 22.5, range = 18-100; 52.5% women) presenting to the emergency department (ED) with an uncomplicated mTBI were enrolled. All participants underwent head computed tomography in the ED and showed no macroscopic evidence of injury. The mean time between injury and blood sampling was 8.3 h (median [Md] = 3.5; SD = 13.5; interquartile range [IQR] = 1.9-6.0, range = 0.8-67.4, and 90% collected within 19 h). A sample of 40 orthopedically-injured trauma control subjects recruited from a second ED also were examined. Serum NF-L levels were measured and analyzed using Human Neurology 4-Plex A assay on a HD-1 Single Molecule Array (Simoa) instrument. A high correlation was found between age and NF-L levels in the total mTBI sample (r = 0.80), within the subgroups without pre-injury neurological diseases (r = 0.76) and with pre-injury neurological diseases (r = 0.68), and in the trauma control subjects (r = 0.76). Those with mTBIs and pre-injury neurological conditions had higher NF-L levels than those with no pre-injury neurological conditions (p < 0.001, Cohen's d = 1.01). Older age and pre-injury neurological diseases are associated with elevated serum NF-L levels in patients with head trauma and in orthopedically-injured control subjects.
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Affiliation(s)
- Grant L Iverson
- 1Department of Physical Medicine and Rehabilitation, Harvard Medical School, Spaulding Rehabilitation Hospital, and Home Base, a Red Sox Foundation and Massachusetts General Hospital Program, Boston, Massachusetts
| | | | - Jussi P Posti
- 3Department of Neurosurgery and Turku University Hospital and University of Turku, Turku, Finland.,4Turku Brain Injury Centre, Turku University Hospital and University of Turku, Turku, Finland
| | | | - Olli Tenovuo
- 4Turku Brain Injury Centre, Turku University Hospital and University of Turku, Turku, Finland
| | - Juha Öhman
- 6Department of Neurosurgery, Tampere University Hospital and University of Tampere, Tampere, Finland
| | - Henrik Zetterberg
- 7Department of Psychiatry and Neurochemistry, the Sahlgrenska Academy at the University of Gothenburg, Mölndal, Sweden.,8Clinical Neurochemistry Laboratory, Sahlgrenska University Hospital, Mölndal, Sweden.,9U.K. Dementia Research Institute at University College London, London, United Kingdom.,10Department of Neurodegenerative Disease, University College London Institute of Neurology, Queen Square, London, United Kingdom
| | - Kaj Blennow
- 7Department of Psychiatry and Neurochemistry, the Sahlgrenska Academy at the University of Gothenburg, Mölndal, Sweden.,8Clinical Neurochemistry Laboratory, Sahlgrenska University Hospital, Mölndal, Sweden
| | - Teemu M Luoto
- 6Department of Neurosurgery, Tampere University Hospital and University of Tampere, Tampere, Finland
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16
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Alteration of O-GlcNAcylation affects assembly and axonal transport of neurofilament via phosphorylation. Neurosci Lett 2019; 698:97-104. [PMID: 30395884 DOI: 10.1016/j.neulet.2018.11.001] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2018] [Revised: 08/26/2018] [Accepted: 11/01/2018] [Indexed: 01/03/2023]
Abstract
Neurofilaments (NFs), the most abundant cytoskeletal components in the mature neuron, are hyperphosphorylated and accumulated in the neuronal cell body of AD brain, and the abnormalities of NFs appear to contribute to neurodegeneration. Although previous studies have showed that O-GlcNAcylation and phosphorylation of NFs regulate each other reciprocally, the NFs O-GlcNAcylation and its effects on assembly and axonal transport are poorly explored. Here, we focus on the role of dysregulation of O-GlcNAcylation on structure and function of neurofilaments by corresponding phosphorylation. In the study, we found that decreased O-GlcNAcylation by intracerebroventricular administration of Alloxan, 6-diazo-5-oxonorleucine (Don) and okadaic acid (OA) in the rats resulted in increased phosphorylation with assembly of lower and shorter NFs. In contrast, in the sample of NAG-thiazoline (NAG-Ae) causing increased O-GlcNAcylation, NFs showed elongated filaments fibers and higher proportion of assembly. Furthermore, alloxan treatment induced abnormal accumulation of NFs bodies and delayed time of Fluorescence Recovery After Photobleaching (FRAP) in SK-N-SH cells, but the NAG-Ae treatment speeded up the axonal transport. Our experiments suggest that increased O-GlcNAcylation plays a key role in protecting the structure and function of NFs including filament assembly and axonal transport via decreased phosphorylation. These results expanded the function of O-GlcNAcylation in AD pathogenesis.
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17
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Prior R, Van Helleputte L, Klingl YE, Van Den Bosch L. HDAC6 as a potential therapeutic target for peripheral nerve disorders. Expert Opin Ther Targets 2018; 22:993-1007. [DOI: 10.1080/14728222.2018.1541235] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Affiliation(s)
- Robert Prior
- Department of Neurosciences, KU Leuven - University of Leuven, Experimental Neurology and Leuven Brain Institute (LBI), Leuven, Belgium
- Center for Brain & Disease Research, Laboratory of Neurobiology, VIB, Leuven, Belgium
| | - Lawrence Van Helleputte
- Department of Neurosciences, KU Leuven - University of Leuven, Experimental Neurology and Leuven Brain Institute (LBI), Leuven, Belgium
- Center for Brain & Disease Research, Laboratory of Neurobiology, VIB, Leuven, Belgium
| | - Yvonne Eileen Klingl
- Department of Neurosciences, KU Leuven - University of Leuven, Experimental Neurology and Leuven Brain Institute (LBI), Leuven, Belgium
- Center for Brain & Disease Research, Laboratory of Neurobiology, VIB, Leuven, Belgium
| | - Ludo Van Den Bosch
- Department of Neurosciences, KU Leuven - University of Leuven, Experimental Neurology and Leuven Brain Institute (LBI), Leuven, Belgium
- Center for Brain & Disease Research, Laboratory of Neurobiology, VIB, Leuven, Belgium
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18
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Moore EE, Hohman TJ, Badami FS, Pechman KR, Osborn KE, Acosta LMY, Bell SP, Babicz MA, Gifford KA, Anderson AW, Goldstein LE, Blennow K, Zetterberg H, Jefferson AL. Neurofilament relates to white matter microstructure in older adults. Neurobiol Aging 2018; 70:233-241. [PMID: 30036759 PMCID: PMC6119102 DOI: 10.1016/j.neurobiolaging.2018.06.023] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2017] [Revised: 06/14/2018] [Accepted: 06/18/2018] [Indexed: 01/10/2023]
Abstract
Cerebrospinal fluid (CSF) neurofilament light (NFL) is a protein biomarker of axonal injury. To study whether NFL is associated with diffusion tensor imaging (DTI) measurements of white matter (WM) microstructure, Vanderbilt Memory & Aging Project participants with normal cognition (n = 77), early mild cognitive impairment (n = 15), and MCI (n = 55) underwent lumbar puncture to obtain CSF and 3T brain MRI. Voxel-wise analyses cross-sectionally related NFL to DTI metrics, adjusting for demographic and vascular risk factors. Increased NFL correlated with multiple DTI metrics (p-values < 0.05). An NFL × diagnosis interaction (excluding early mild cognitive impairment) on WM microstructure (p-values < 0.05) was detected, with associations strongest among MCI. Multiple NFL × CSF biomarker interactions were detected. Associations between NFL and worse WM metrics were strongest among amyloid-β42-negative, tau-positive, and suspected nonamyloid pathology participants. Findings suggest increased NFL, a biomarker of axonal injury, is correlated with compromised WM microstructure. Results highlight the role of elevated NFL in predicting WM damage in cognitively impaired older adults who are amyloid-negative, tau-positive, or meet suspected nonamyloid pathology criteria.
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Affiliation(s)
- Elizabeth E Moore
- Department of Neurology, Vanderbilt Memory & Alzheimer's Center, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Timothy J Hohman
- Department of Neurology, Vanderbilt Memory & Alzheimer's Center, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Faizan S Badami
- Department of Neurology, Vanderbilt Memory & Alzheimer's Center, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Kimberly R Pechman
- Department of Neurology, Vanderbilt Memory & Alzheimer's Center, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Katie E Osborn
- Department of Neurology, Vanderbilt Memory & Alzheimer's Center, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Lealani Mae Y Acosta
- Department of Neurology, Vanderbilt Memory & Alzheimer's Center, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Susan P Bell
- Department of Neurology, Vanderbilt Memory & Alzheimer's Center, Vanderbilt University Medical Center, Nashville, TN, USA; Division of Cardiovascular Medicine, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Michelle A Babicz
- Department of Neurology, Vanderbilt Memory & Alzheimer's Center, Vanderbilt University Medical Center, Nashville, TN, USA; Department of Psychology, University of Houston, Houston, TX, USA
| | - Katherine A Gifford
- Department of Neurology, Vanderbilt Memory & Alzheimer's Center, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Adam W Anderson
- Department of Biomedical Engineering, Vanderbilt University, Nashville, TN, USA
| | - Lee E Goldstein
- Departments of Psychiatry, Neurology, Radiology, Pathology & Laboratory Medicine, Biomedical Engineering, Electrical & Computer Engineering, Boston University School of Medicine and College of Engineering, Boston, MA, USA
| | - Kaj Blennow
- Department of Psychiatry and Neurochemistry, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at University of Gothenburg, Mölndal, Sweden; Clinical Neurochemistry Lab, Sahlgrenska University Hospital, Mölndal, Sweden
| | - Henrik Zetterberg
- Department of Psychiatry and Neurochemistry, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at University of Gothenburg, Mölndal, Sweden; Clinical Neurochemistry Lab, Sahlgrenska University Hospital, Mölndal, Sweden; Department of Molecular Neuroscience, UCL Institute of Neurology, Queen Square, London, UK; UK Dementia Research Institute at UCL, London, UK
| | - Angela L Jefferson
- Department of Neurology, Vanderbilt Memory & Alzheimer's Center, Vanderbilt University Medical Center, Nashville, TN, USA.
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19
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Bian X, Lin P, Li J, Long F, Duan R, Yuan Q, Li Y, Gao F, Gao S, Wei S, Li X, Sun W, Gong Y, Yan C, Liu Q. Whole-Genome Linkage Analysis with Whole-Exome Sequencing Identifies a Novel Frameshift Variant in NEFH in a Chinese Family with Charcot-Marie-Tooth 2: A Novel Variant in NEFH for Charcot-Marie-Tooth 2. NEURODEGENER DIS 2018; 18:74-83. [PMID: 29587262 DOI: 10.1159/000487754] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2017] [Accepted: 02/16/2018] [Indexed: 12/23/2022] Open
Abstract
BACKGROUND Charcot-Marie-Tooth disease (CMT) is the most common neurodegenerative disorder of the peripheral nervous system. More than 50 genes/loci were found associated with the disease. We found a family with autosomal-dominant CMT2. OBJECTIVE To reveal the pathogenic gene of the family and further investigate the function of the variant. METHODS DNA underwent whole-genome linkage analysis for all family members and whole-exome sequencing for 2 affected members. Neurofilament light polypeptide and wild-type or mutant neurofilament heavy polypeptide (NEFH) were co-transfected into SW13 (vim-) cells. The nefh-knockdown zebrafish model was produced by using morpholino antisense oligonucleotides. RESULTS We identified a novel insertion variant (c.3057insG) in NEFH in the family. The variant led to the loss of a stop codon and an extended 41 amino acids in the protein. Immunofluorescence results revealed that mutant NEFH disrupted the neurofilament network and induced aggregation of NEFH protein. Knockdown of nefh in zebrafish caused a slightly or severely curled tail. The motor ability of nefh-knockdown embryos was impaired or even absent, and the embryos showed developmental defects of axons in motor neurons. The abnormal phenotype and axonal developmental defects could be rescued by injection of human wild-type but not human mutant NEFH mRNA. CONCLUSIONS We identified a novel stop loss variant in NEFH that is likely pathogenic for CMT2, and the results provide further evidence for the role of an aberrant assembly of neurofilament in CMT.
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Affiliation(s)
- Xianli Bian
- Key Laboratory for Experimental Teratology of the Ministry of Education and Department of Medical Genetics, Shandong University School of Medicine, Jinan, China
| | - Pengfei Lin
- Department of Neurology, Qilu Hospital of Shandong University, Jinan, China
| | - Jiangxia Li
- Key Laboratory for Experimental Teratology of the Ministry of Education and Department of Medical Genetics, Shandong University School of Medicine, Jinan, China
| | - Feng Long
- Key Laboratory for Experimental Teratology of the Ministry of Education and Department of Medical Genetics, Shandong University School of Medicine, Jinan, China
| | - Ruonan Duan
- Key Laboratory for Experimental Teratology of the Ministry of Education and Department of Medical Genetics, Shandong University School of Medicine, Jinan, China
| | - Qianqian Yuan
- Key Laboratory for Experimental Teratology of the Ministry of Education and Department of Medical Genetics, Shandong University School of Medicine, Jinan, China
| | - Yan Li
- Key Laboratory for Experimental Teratology of the Ministry of Education and Department of Medical Genetics, Shandong University School of Medicine, Jinan, China
| | - Fei Gao
- Key Laboratory for Experimental Teratology of the Ministry of Education and Department of Medical Genetics, Shandong University School of Medicine, Jinan, China
| | - Shang Gao
- Key Laboratory for Experimental Teratology of the Ministry of Education and Department of Medical Genetics, Shandong University School of Medicine, Jinan, China
| | - Shijun Wei
- Key Laboratory for Experimental Teratology of the Ministry of Education and Department of Medical Genetics, Shandong University School of Medicine, Jinan, China
| | - Xi Li
- Key Laboratory for Experimental Teratology of the Ministry of Education and Department of Medical Genetics, Shandong University School of Medicine, Jinan, China
| | - Wenjie Sun
- Key Laboratory for Experimental Teratology of the Ministry of Education and Department of Medical Genetics, Shandong University School of Medicine, Jinan, China
| | - Yaoqin Gong
- Key Laboratory for Experimental Teratology of the Ministry of Education and Department of Medical Genetics, Shandong University School of Medicine, Jinan, China
| | - Chuanzhu Yan
- Department of Neurology, Qilu Hospital of Shandong University, Jinan, China
| | - Qiji Liu
- Key Laboratory for Experimental Teratology of the Ministry of Education and Department of Medical Genetics, Shandong University School of Medicine, Jinan, China
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20
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Prior R, Van Helleputte L, Benoy V, Van Den Bosch L. Defective axonal transport: A common pathological mechanism in inherited and acquired peripheral neuropathies. Neurobiol Dis 2017; 105:300-320. [DOI: 10.1016/j.nbd.2017.02.009] [Citation(s) in RCA: 72] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2016] [Revised: 01/29/2017] [Accepted: 02/20/2017] [Indexed: 12/29/2022] Open
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21
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Horga A, Laurà M, Jaunmuktane Z, Jerath NU, Gonzalez MA, Polke JM, Poh R, Blake JC, Liu YT, Wiethoff S, Bettencourt C, Lunn MP, Manji H, Hanna MG, Houlden H, Brandner S, Züchner S, Shy M, Reilly MM. Genetic and clinical characteristics of NEFL-related Charcot-Marie-Tooth disease. J Neurol Neurosurg Psychiatry 2017; 88:575-585. [PMID: 28501821 PMCID: PMC5580821 DOI: 10.1136/jnnp-2016-315077] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/13/2016] [Revised: 01/20/2017] [Accepted: 01/24/2017] [Indexed: 11/03/2022]
Abstract
OBJECTIVES To analyse and describe the clinical and genetic spectrum of Charcot-Marie-Tooth disease (CMT) caused by mutations in the neurofilament light polypeptide gene (NEFL). METHODS Combined analysis of newly identified patients with NEFL-related CMT and all previously reported cases from the literature. RESULTS Five new unrelated patients with CMT carrying the NEFL mutations P8R and N98S and the novel variant L311P were identified. Combined data from these cases and 62 kindreds from the literature revealed four common mutations (P8R, P22S, N98S and E396K) and three mutational hotspots accounting for 37 (55%) and 50 (75%) kindreds, respectively. Eight patients had de novo mutations. Loss of large-myelinated fibres was a uniform feature in a total of 21 sural nerve biopsies and 'onion bulb' formations and/or thin myelin sheaths were observed in 14 (67%) of them. The neurophysiological phenotype was broad but most patients with E90K and N98S had upper limb motor conduction velocities <38 m/s. Age of onset was ≤3 years in 25 cases. Pyramidal tract signs were described in 13 patients and 7 patients were initially diagnosed with or tested for inherited ataxia. Patients with E90K and N98S frequently presented before age 3 years and developed hearing loss or other neurological features including ataxia and/or cerebellar atrophy on brain MRI. CONCLUSIONS NEFL-related CMT is clinically and genetically heterogeneous. Based on this study, however, we propose mutational hotspots and relevant clinical-genetic associations that may be helpful in the evaluation of NEFL sequence variants and the differential diagnosis with other forms of CMT.
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Affiliation(s)
- Alejandro Horga
- MRC Centre for Neuromuscular Diseases, UCL Institute of Neurology, London, UK.,Department of Neurology, Hospital Clinico Universitario San Carlos, Madrid, Spain
| | - Matilde Laurà
- MRC Centre for Neuromuscular Diseases, UCL Institute of Neurology, London, UK.,UCL Institute of Neurology, MRC Centre for Neuromuscular Diseases, National Hospital for Neurology and Neurosurgery, London, UK
| | - Zane Jaunmuktane
- Division of Neuropathology and Department of Neurodegenerative Disease, The National Hospital for Neurology and Neurosurgery and UCL Institute of Neurology, London, UK
| | | | - Michael A Gonzalez
- Department of Human Genetics and Hussman Institute for Human Genomics, Miller School of Medicine, University of Miami, Miami, Florida, USA.,The Genesis Project Foundation, The Genesis Project Foundation, Miami, Florida, USA
| | - James M Polke
- Department of Neurogenetics, The National Hospital for Neurology and Neurosurgery and UCL Institute of Neurology, London, UK.,Neurogenetics Unit, National Hospital for Neurology and Neurosurgery, London, UK
| | - Roy Poh
- Department of Neurogenetics, The National Hospital for Neurology and Neurosurgery and UCL Institute of Neurology, London, UK
| | - Julian C Blake
- Department of Clinical Neurophysiology, National Hospital for Neurology and Neurosurgery (and Norfolk and Norwich University Hospital), London, UK
| | - Yo-Tsen Liu
- MRC Centre for Neuromuscular Diseases, UCL Institute of Neurology, London, UK.,Department of Neurology, Neurological Institute, Taipei Veterans General Hospital, Taipei, Taiwan
| | - Sarah Wiethoff
- Department of Molecular Neuroscience, UCL Institute of Neurology, London, UK
| | | | - Michael Pt Lunn
- Department of Neurology, National Hospital for Neurology and Neurosurgery, London, UK
| | - Hadi Manji
- MRC Centre for Neuromuscular Diseases, UCL Institute of Neurology, London, UK
| | - Michael G Hanna
- MRC Centre for Neuromuscular Diseases, UCL Institute of Neurology, London, UK
| | - Henry Houlden
- MRC Centre for Neuromuscular Diseases, UCL Institute of Neurology and National Hospital for Neurology and Neurosurgery, London, UK
| | - Sebastian Brandner
- Division of Neuropatholgoy, UCL Institute of Neurology and National Hospital for Neurology and Neurosurgery, London, UK
| | | | - Michael Shy
- Department of Neurology, University of Iowa, Iowa City, Iowa, USA.,Wayne State University, Michigan, Michigan, USA
| | - Mary M Reilly
- MRC Centre for Neuromuscular Diseases, UCL Institute of Neurology, London, UK.,MRC Centre for Neuromuscular Diseases, UCL Institute of Neurology and National Hospital for Neurology and Neurosurgery, London, UK
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22
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Nefedova VV, Sudnitsyna MV, Gusev NB. Interaction of small heat shock proteins with light component of neurofilaments (NFL). Cell Stress Chaperones 2017; 22:467-479. [PMID: 28000086 PMCID: PMC5465025 DOI: 10.1007/s12192-016-0757-6] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2016] [Revised: 12/08/2016] [Accepted: 12/09/2016] [Indexed: 11/26/2022] Open
Abstract
The interaction of human small heat shock protein HspB1, its point mutants associated with distal hereditary motor neuropathy, and three other small heat shock proteins (HspB5, HspB6, HspB8) with the light component of neurofilaments (NFL) was analyzed by differential centrifugation, analytical ultracentrifugation, and fluorescent spectroscopy. The wild-type HspB1 decreased the quantity of NFL in pellets obtained after low- and high-speed centrifugation and increased the quantity of NFL remaining in the supernatant after high-speed centrifugation. Part of HspB1 was detected in the pellet of NFL after high-speed centrifugation, and at saturation, 1 mol of HspB1 monomer was bound per 2 mol of NFL. Point mutants of HspB1 associated with distal hereditary motor neuropathy (G84R, L99M, R140G, K141Q, and P182S) were almost as effective as the wild-type HspB1 in modulation of NFL assembly. At low ionic strength, HspB1 weakly interacted with NFL tetramers, and this interaction was increased upon salt-induced polymerization of NFL. HspB1 and HspB5 (αB-crystallin) decreased the rate of NFL polymerization measured by fluorescent spectroscopy. HspB6 (Hsp20) and HspB8 (Hsp22) were less effective than HspB1 (or HspB5) in modulation of NFL assembly. The data presented indicate that the small heat shock proteins affect NFL transition from tetramers to filaments, hydrodynamic properties of filaments, and their bundling and therefore probably modulate the formation of intermediate filament networks in neurons.
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Affiliation(s)
- Victoria V Nefedova
- Department of Biochemistry, School of Biology, Moscow State University, Moscow, Russian Federation, 119991
| | - Maria V Sudnitsyna
- Department of Biochemistry, School of Biology, Moscow State University, Moscow, Russian Federation, 119991
| | - Nikolai B Gusev
- Department of Biochemistry, School of Biology, Moscow State University, Moscow, Russian Federation, 119991.
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Kirkcaldie MTK, Dwyer ST. The third wave: Intermediate filaments in the maturing nervous system. Mol Cell Neurosci 2017; 84:68-76. [PMID: 28554564 DOI: 10.1016/j.mcn.2017.05.010] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2017] [Revised: 05/10/2017] [Accepted: 05/25/2017] [Indexed: 01/16/2023] Open
Abstract
Intermediate filaments are critical for the extreme structural specialisations of neurons, providing integrity in dynamic environments and efficient communication along axons a metre or more in length. As neurons mature, an initial expression of nestin and vimentin gives way to the neurofilament triplet proteins and α-internexin, substituted by peripherin in axons outside the CNS, which physically consolidate axons as they elongate and find their targets. Once connection is established, these proteins are transported, assembled, stabilised and modified, structurally transforming axons and dendrites as they acquire their full function. The interaction between these neurons and myelinating glial cells optimises the structure of axons for peak functional efficiency, a property retained across their lifespan. This finely calibrated structural regulation allows the nervous system to maintain timing precision and efficient control across large distances throughout somatic growth and, in maturity, as a plasticity mechanism allowing functional adaptation.
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Affiliation(s)
- Matthew T K Kirkcaldie
- School of Medicine, Wicking Dementia Research and Education Centre, Faculty of Health, University of Tasmania, Australia.
| | - Samuel T Dwyer
- School of Medicine, Wicking Dementia Research and Education Centre, Faculty of Health, University of Tasmania, Australia
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The tail domain is essential but the head domain dispensable for C. elegans intermediate filament IFA-2 function. PLoS One 2015; 10:e0119282. [PMID: 25742641 PMCID: PMC4351089 DOI: 10.1371/journal.pone.0119282] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2014] [Accepted: 01/19/2015] [Indexed: 01/12/2023] Open
Abstract
The intermediate filament protein IFA-2 is essential for the structural integrity of the Caenorhabditis elegans epidermis. It is one of the major components of the fibrous organelle, an epidermal structure comprised of apical and basal hemidesmosomes linked by cytoplasmic intermediate filaments that serve to transmit force from the muscle to the cuticle. Mutations of IFA-2 result in epidermal fragility and separation of the apical and basal epidermal surfaces during postembryonic growth. An IFA-2 lacking the head domain fully rescues the IFA-2 null mutant, whereas an IFA-2 lacking the tail domain cannot. Conversely, an isolated IFA-2 head was able to localize to fibrous organelles whereas the tail was not. Taken together these results suggest that the head domain contains redundant signals for IF localization, whereas non-redundant essential functions map to the IFA-2, tail, although the tail is unlikely to be directly involved in fibrous organelle localization.
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Laser-Azogui A, Kornreich M, Malka-Gibor E, Beck R. Neurofilament assembly and function during neuronal development. Curr Opin Cell Biol 2015; 32:92-101. [PMID: 25635910 DOI: 10.1016/j.ceb.2015.01.003] [Citation(s) in RCA: 84] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2014] [Revised: 01/06/2015] [Accepted: 01/09/2015] [Indexed: 02/06/2023]
Abstract
Studies on the assembly of neuronal intermediate filaments (IFs) date back to the early work of Alzheimer. Developing neurons express a series of IF proteins, sequentially, at distinct stages of mammalian cell differentiation. This correlates with altered morphologies during the neuronal development, including axon outgrowth, guidance and conductivity. Importantly, neuronal IFs that fail to properly assemble into a filamentous network are a hallmark of neurodegenerative diseases such as amyotrophic lateral sclerosis, Alzheimer's, and Parkinson's disease. Traditional structural methodologies fail to fully describe neuronal IF assembly, interactions and resulting function due to IFs structural plasticity, particularly in their C-terminal domains. We review here current progress in the field of neuronal-specific IFs, a dominant component affecting the cytoskeletal structure and function of neurons.
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Affiliation(s)
- Adi Laser-Azogui
- The Raymond and Beverly Sackler School of Physics and Astronomy, Tel-Aviv University, Tel-Aviv 69978, Israel
| | - Micha Kornreich
- The Raymond and Beverly Sackler School of Physics and Astronomy, Tel-Aviv University, Tel-Aviv 69978, Israel
| | - Eti Malka-Gibor
- Sackler Faculty of Medicine, Tel-Aviv University, Tel-Aviv 69978, Israel
| | - Roy Beck
- The Raymond and Beverly Sackler School of Physics and Astronomy, Tel-Aviv University, Tel-Aviv 69978, Israel.
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26
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Gentil BJ, Tibshirani M, Durham HD. Neurofilament dynamics and involvement in neurological disorders. Cell Tissue Res 2015; 360:609-20. [PMID: 25567110 DOI: 10.1007/s00441-014-2082-7] [Citation(s) in RCA: 66] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2014] [Accepted: 11/19/2014] [Indexed: 12/21/2022]
Abstract
Neurons are extremely polarised cells in which the cytoskeleton, composed of microtubules, microfilaments and neurofilaments, plays a crucial role in maintaining structure and function. Neurofilaments, the 10-nm intermediate filaments of neurons, provide structure and mechanoresistance but also provide a scaffolding for the organization of the nucleus and organelles such as mitochondria and ER. Disruption of neurofilament organization and expression or metabolism of neurofilament proteins is characteristic of certain neurological syndromes including Amyotrophic Lateral Sclerosis, Charcot-Marie-Tooth sensorimotor neuropathies and Giant Axonal Neuropathy. Microfluorometric live imaging techniques have been instrumental in revealing the dynamics of neurofilament assembly and transport and their functions in organizing intracellular organelle networks. The insolubility of neurofilament proteins has limited identifying interactors by conventional biochemical techniques but yeast two-hybrid experiments have revealed new roles for oligomeric, nonfilamentous structures including vesicular trafficking. Although having long half-lives, new evidence points to degradation of subunits by the ubiquitin-proteasome system as a mechanism of normal turnover. Although certain E3-ligases ubiquitinating neurofilament proteins have been identified, the overall process of neurofilament degradation is not well understood. We review these mechanisms of neurofilament homeostasis and abnormalities in motor neuron and peripheral nerve disorders. Much remains to discover about the disruption of processes that leads to their pathological aggregation and accumulation and the relevance to pathogenesis. Understanding these mechanisms is crucial for identifying novel therapeutic strategies.
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Affiliation(s)
- Benoit J Gentil
- Department of Neurology/Neurosurgery and Montreal Neurological Institute, McGill University, Montreal, QC, H3A 2B4, Canada,
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27
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Politis C, Lambrichts I, Agbaje JO. Neuropathic pain after orthognathic surgery. Oral Surg Oral Med Oral Pathol Oral Radiol 2013; 117:e102-7. [PMID: 24120908 DOI: 10.1016/j.oooo.2013.08.001] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2013] [Revised: 06/21/2013] [Accepted: 08/02/2013] [Indexed: 11/25/2022]
Abstract
OBJECTIVE This study assesses the incidence of neuropathic pain after orthognathic surgery at our center and briefly reports the cases found. STUDY DESIGN All records of orthognathic surgical patients between 2001 and 2011 were exported from the hospital information system into a Portable Document Format platform (Adobe Acrobat) to simplify keyword searching. Records of patients that developed debilitating chronic pain were isolated and examined. RESULTS Records included 982 bilateral sagittal split osteotomies, 536 LeFort I procedures, and 335 surgically assisted rapid palatal expansion procedures. Six records were identified that described cases in which patients developed debilitating chronic neuropathic pain after orthognathic surgery (mean age at surgery, 43 years). CONCLUSIONS The exposure of the inferior alveolar nerve or partial axonal injury together with a disruption of the bony environment of the inferior alveolar nerve is a risk factor after bilateral sagittal split osteotomy.
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Affiliation(s)
- Constantinus Politis
- Professor, Department of Oral Health Sciences; Professor and Department Head, Department of Oral and Maxillofacial Surgery, Katholieke Universiteit Leuven and University Hospitals Leuven; Professor, Faculty of Medicine, Hasselt University, Leuven.
| | - Ivo Lambrichts
- Professor and Senior Lecturer, Faculty of Medicine, Hasselt University, Diepenbeek; and St John's Hospital, Genk, Belgium
| | - Jimoh Olubanwo Agbaje
- Professor, Department of Oral Health Sciences and Department of Oral and Maxillofacial Surgery, Katholieke Universiteit Leuven and University Hospitals Leuven; Researcher, Oral and Maxillofacial Surgery, St John's Hospital, Genk, Belgium
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28
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Holmgren A, Bouhy D, De Winter V, Asselbergh B, Timmermans JP, Irobi J, Timmerman V. Charcot-Marie-Tooth causing HSPB1 mutations increase Cdk5-mediated phosphorylation of neurofilaments. Acta Neuropathol 2013; 126:93-108. [PMID: 23728742 PMCID: PMC3963106 DOI: 10.1007/s00401-013-1133-6] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2013] [Revised: 05/03/2013] [Accepted: 05/21/2013] [Indexed: 01/21/2023]
Abstract
Mutations in the small heat shock protein HSPB1 (HSP27) are a cause of axonal Charcot-Marie-Tooth neuropathy (CMT2F) and distal hereditary motor neuropathy. To better understand the effect of mutations in HSPB1 on the neuronal cytoskeleton, we stably transduced neuronal cells with wild-type and mutant HSPB1 and investigated axonal transport of neurofilaments (NFs). We observed that mutant HSPB1 affected the binding of NFs to the anterograde motor protein kinesin, reducing anterograde transport of NFs. These deficits were associated with an increased phosphorylation of NFs and cyclin-dependent kinase Cdk5. As Cdk5 mediates NF phosphorylation, inhibition of Cdk5/p35 restored NF phosphorylation level, as well as NF binding to kinesin in mutant HSPB1 neuronal cells. Altogether, we demonstrate that HSPB1 mutations induce hyperphosphorylation of NFs through Cdk5 and reduce anterograde transport of NFs.
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Affiliation(s)
- Anne Holmgren
- Department of Molecular Genetics, VIB and University of Antwerp, 2610 Antwerpen, Belgium
- Laboratory of Neurogenetics, Institute Born-Bunge, 2610 Antwerpen, Belgium
| | - Delphine Bouhy
- Department of Molecular Genetics, VIB and University of Antwerp, 2610 Antwerpen, Belgium
- Laboratory of Neurogenetics, Institute Born-Bunge, 2610 Antwerpen, Belgium
| | - Vicky De Winter
- Department of Molecular Genetics, VIB and University of Antwerp, 2610 Antwerpen, Belgium
- Laboratory of Neurogenetics, Institute Born-Bunge, 2610 Antwerpen, Belgium
| | - Bob Asselbergh
- Department of Molecular Genetics, VIB and University of Antwerp, 2610 Antwerpen, Belgium
- Laboratory of Neurogenetics, Institute Born-Bunge, 2610 Antwerpen, Belgium
| | - Jean-Pierre Timmermans
- Laboratory of Cell Biology and Histology, Department of Veterinary Sciences, University of Antwerp, 2020 Antwerpen, Belgium
| | - Joy Irobi
- Department of Molecular Genetics, VIB and University of Antwerp, 2610 Antwerpen, Belgium
- Laboratory of Neurogenetics, Institute Born-Bunge, 2610 Antwerpen, Belgium
| | - Vincent Timmerman
- Department of Molecular Genetics, VIB and University of Antwerp, 2610 Antwerpen, Belgium
- Laboratory of Neurogenetics, Institute Born-Bunge, 2610 Antwerpen, Belgium
- Peripheral Neuropathy Group, VIB Department of Molecular Genetics, University of Antwerp, Universiteitsplein 1, 2610 Antwerpen, Belgium
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Gentil BJ, Mushynski WE, Durham HD. Heterogeneity in the properties of NEFL mutants causing Charcot-Marie-Tooth disease results in differential effects on neurofilament assembly and susceptibility to intervention by the chaperone-inducer, celastrol. Int J Biochem Cell Biol 2013; 45:1499-508. [PMID: 23618875 DOI: 10.1016/j.biocel.2013.04.009] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2013] [Accepted: 04/05/2013] [Indexed: 11/25/2022]
Abstract
Aberrant aggregation of neurofilament proteins is a common feature of neurodegenerative diseases. For example, neurofilament light protein (NEFL) mutants causing Charcot-Marie-Tooth disease induce misassembly of neurofilaments. This study demonstrated that mutations in different functional domains of NEFL have different effects on filament assembly and susceptibility to interventions to restore function. The mouse NEFL mutants, NEFL(Q333P) and NEFL(P8R), exhibited different assembly properties in SW13-cells, cells lacking endogenous intermediate filaments, indicating different consequences of these mutations on the biochemical properties of NEFL. The p.Q333P mutation caused reversible misfolding of the protein. NEFL(Q333P) could be refolded and form coil-coiled dimers, in vitro using chaotropic agent, and in cultured cells by induction of HSPA1 and HSPB1. Celastrol, an inducer of chaperone proteins, induced HSPA1 expression in motor neurons and prevented the formation of neurofilament inclusions and mitochondrial shortening induced by expression of NEFL(Q333P), but not in sensory neurons. Conversely, celastrol had a protective effect against the toxicity of NEFL(P8R), a mutant which is sensitive to HSBP1 but not HSPA1 chaperoning, only in large-sized sensory neurons, not in motor neurons. Importantly, sensory and motor neurons do not respond identically to celastrol and different chaperones are upregulated by the same treatment. Thus, effective therapy of CMT not only depends on the identity of the mutated gene, but the consequences of the specific mutation on the properties of the protein and the neuronal population targeted.
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Affiliation(s)
- Benoit J Gentil
- Department of Neurology/Neurosurgery and Montreal Neurological Institute, Montreal, QC, Canada.
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30
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Affiliation(s)
- Aidong Yuan
- Center for Dementia Research, Nathan Kline Institute, Orangeburg, New York, NY 10962, USA.
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31
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Berges R, Balzeau J, Takahashi M, Prevost C, Eyer J. Structure-function analysis of the glioma targeting NFL-TBS.40-63 peptide corresponding to the tubulin-binding site on the light neurofilament subunit. PLoS One 2012; 7:e49436. [PMID: 23152907 PMCID: PMC3494675 DOI: 10.1371/journal.pone.0049436] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2012] [Accepted: 10/08/2012] [Indexed: 11/23/2022] Open
Abstract
We previously reported that a 24 amino acid peptide (NFL-TBS.40-63) corresponding to the tubulin-binding site located on the light neurofilament subunit, selectively enters in glioblastoma cells where it disrupts their microtubule network and inhibits their proliferation. Here, we analyzed the structure-function relationships using an alanine-scanning strategy, in order to identify residues essential for these biological activities. We showed that the majority of modified peptides present a decreased or total loss to penetrate in these cells, or to alter microtubules. Correspondingly, circular dichroism measurements showed that this peptide forms either β-sheet or α-helix structures according to the solvent and that alanine substitution modified or destabilized the structure, in relation with changes in the biological activities. Moreover, substitution of serine residues by phosphoserine or aspartic acid concomitantly decreased the cell penetrating activity and the structure stability. These results indicate the importance of structure for the activities, including selectivity to glioblastoma cells of this peptide, and its regulation by phosphorylation.
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Affiliation(s)
| | | | | | | | - Joel Eyer
- Laboratoire de Neurobiologie & Transgenèse, UPRES EA 3143, INSERM, Centre Hospitalier Universitaire, Angers, France
- * E-mail:
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32
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Rao MV, Yuan A, Campbell J, Kumar A, Nixon RA. The C-terminal domains of NF-H and NF-M subunits maintain axonal neurofilament content by blocking turnover of the stationary neurofilament network. PLoS One 2012; 7:e44320. [PMID: 23028520 PMCID: PMC3448626 DOI: 10.1371/journal.pone.0044320] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2012] [Accepted: 08/01/2012] [Indexed: 02/03/2023] Open
Abstract
Newly synthesized neurofilaments or protofilaments are incorporated into a highly stable stationary cytoskeleton network as they are transported along axons. Although the heavily phosphorylated carboxyl-terminal tail domains of the heavy and medium neurofilament (NF) subunits have been proposed to contribute to this process and particularly to stability of this structure, their function is still obscure. Here we show in NF-H/M tail deletion [NF-(H/M)(tailΔ)] mice that the deletion of both of these domains selectively lowers NF levels 3-6 fold along optic axons without altering either rates of subunit synthesis or the rate of slow axonal transport of NF. Pulse labeling studies carried out over 90 days revealed a significantly faster rate of disappearance of NF from the stationary NF network of optic axons in NF-(H/M)(tailΔ) mice. Faster NF disappearance was accompanied by elevated levels of NF-L proteolytic fragments in NF-(H/M)(tailΔ) axons. We conclude that NF-H and NF-M C-terminal domains do not normally regulate NF transport rates as previously proposed, but instead increase the proteolytic resistance of NF, thereby stabilizing the stationary neurofilament cytoskeleton along axons.
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Affiliation(s)
- Mala V Rao
- Center for Dementia Research, Nathan Kline Institute, Orangeburg, New York, United States of America.
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Gentil BJ, Cooper L. Molecular basis of axonal dysfunction and traffic impairments in CMT. Brain Res Bull 2012; 88:444-53. [PMID: 22595495 DOI: 10.1016/j.brainresbull.2012.05.003] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2011] [Revised: 05/01/2012] [Accepted: 05/04/2012] [Indexed: 12/17/2022]
Abstract
Charcot-Marie-Tooth disease (CMT) is one of the most common inherited neurological disorders. It comprises a group of diseases caused by mutations in genes involved in Schwann cells homeostasis and neuronal function that affect the peripheral nerves. So far mutations in more than 33 genes have been identified causing either the demyelinating form (CMT1) or the axonal form (CMT2). Genes involving a large variety of unrelated functions may lead to the same phenotype when mutated. Our review will focus on the common link between genes causing axonal phenotypes like MFN2, KIF1B, DYNC1H1, Rab7, TRPV4, ARSs, NEFL, HSPB1, MPZ, and HSPB8. While KIF1B and DYNC1H1, two genes coding for molecular motors, are directly linked to axonal transport, the involvement of the other CMT2-causing genes in this function is less obvious. However, the last years have seen a growing list of evidence demonstrating that intracellular trafficking and mitochondrial dynamics might be dysfunctional in CMT2, and these mechanisms might present a common link between dissimilar CMT2-causing genes. The involvement of impaired transport in the pathogenesis of other rare neurological diseases or recessive CMT2 is also discussed.
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Affiliation(s)
- Benoit J Gentil
- Department of Neurology/Neurosurgery and Montreal Neurological Institute, McGill University, Montreal, QC H3A 2B4 Canada.
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Neurofilament Phosphorylation during Development and Disease: Which Came First, the Phosphorylation or the Accumulation? JOURNAL OF AMINO ACIDS 2012; 2012:382107. [PMID: 22570767 PMCID: PMC3337605 DOI: 10.1155/2012/382107] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/17/2011] [Accepted: 01/31/2012] [Indexed: 11/17/2022]
Abstract
Posttranslational modification of proteins is a ubiquitous cellular mechanism for regulating protein function. Some of the most heavily modified neuronal proteins are cytoskeletal proteins of long myelinated axons referred to as neurofilaments (NFs). NFs are type IV intermediate filaments (IFs) that can be composed of four subunits, neurofilament heavy (NF-H), neurofilament medium (NF-M), neurofilament light (NF-L), and α-internexin. Within wild type axons, NFs are responsible for mediating radial growth, a process that determines axonal diameter. NFs are phosphorylated on highly conserved lysine-serine-proline (KSP) repeats located along the C-termini of both NF-M and NF-H within myelinated axonal regions. Phosphorylation is thought to regulate aspects of NF transport and function. However, a key pathological hallmark of several neurodegenerative diseases is ectopic accumulation and phosphorylation of NFs. The goal of this review is to provide an overview of the posttranslational modifications that occur in both normal and diseased axons. We review evidence that challenges the role of KSP phosphorylation as essential for radial growth and suggests an alternative role for NF phosphorylation in myelinated axons. Furthermore, we demonstrate that regulation of NF phosphorylation dynamics may be essential to avoiding NF accumulations.
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Kim SK, Kim H, Yang YR, Suh PG, Chang JS. Phosphatidylinositol phosphates directly bind to neurofilament light chain (NF-L) for the regulation of NF-L self assembly. Exp Mol Med 2011; 43:153-60. [PMID: 21339697 DOI: 10.3858/emm.2011.43.3.019] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
Abstract
Phosphatidylinositol phosphates (PtdInsPs) are ubiquitous membrane phospholipids that play diverse roles in cell growth and differentiation. To clarify the regulation mechanism acting on neurofilament light chain (NF-L) self assembly, we examined the effects of various PtdInsPs on this process. We found that PtdInsPs, including PI(4,5)P((2)), directly bind to the positively charged Arg(54) of murine NF-L, and this binding promotes NF-L self assembly in vitro. Mutant NF-L (R53A/R54A) proteins lacking binding affinity to PtdInsPs did not have the same effect, but the mutant NF-L proteins showed greater self assembly than the wild-type in the absence of any PtdInsP. These results collectively suggest that Arg(54) plays a pivotal role in NF-L self assembly by binding with PtdInsPs.
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Affiliation(s)
- Sung-Kuk Kim
- Department of Life Science, College of Natural Science, Daejin University, Kyeonggido, Korea
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36
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Vagnoni A, Rodriguez L, Manser C, De Vos KJ, Miller CCJ. Phosphorylation of kinesin light chain 1 at serine 460 modulates binding and trafficking of calsyntenin-1. J Cell Sci 2011; 124:1032-42. [PMID: 21385839 DOI: 10.1242/jcs.075168] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
Kinesin light chain 1 (KLC1) binds to the intracellular cytoplasmic domain of the type-1 membrane-spanning protein calsyntenin-1 (also known as alcadein-α) to mediate transport of a subset of vesicles. Here, we identify serine 460 in KLC1 (KLC1ser460) as a phosphorylation site and show that mutation of KLC1ser460 influences the binding of KLC1 to calsyntenin-1. Mutation of KLC1ser460 to an alanine residue, to preclude phosphorylation, increased the binding of calsyntenin-1, whereas mutation to an aspartate residue, to mimic permanent phosphorylation, reduced the binding. Mutation of KLC1ser460 did not affect the interaction of KLC1 with four other known binding partners: huntingtin-associated protein 1 isoform A (HAP1A), collapsin response mediator protein-2 (CRMP2), c-Jun N-terminal kinase-interacting protein-1 (JIP1) and kinase-D-interacting substrate of 220 kDa (Kidins220). KLC1ser460 is a predicted mitogen-activated protein kinase (MAPK) target site, and we show that extracellular-signal-regulated kinase (ERK) phosphorylates this residue in vitro. We also demonstrate that inhibition of ERK promotes binding of calsyntenin-1 to KLC1. Finally, we show that expression of the KLC1ser460 mutant proteins influences calsyntenin-1 distribution and transport in cultured cells. Thus, phosphorylation of KLC1ser460 represents a mechanism for selectively regulating the binding and trafficking of calsyntenin-1.
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Affiliation(s)
- Alessio Vagnoni
- MRC Centre for Neurodegeneration Research, Institute of Psychiatry, King's College London, PO Box 37, De Crespigny Park, Denmark Hill, London SE5 8AF, UK
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Zhou J, Wang H, Xiong Y, Li Z, Feng Y, Chen J. Puerarin attenuates glutamate-induced neurofilament axonal transport impairment. JOURNAL OF ETHNOPHARMACOLOGY 2010; 132:150-156. [PMID: 20727960 DOI: 10.1016/j.jep.2010.08.005] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/27/2010] [Revised: 07/09/2010] [Accepted: 08/06/2010] [Indexed: 05/29/2023]
Abstract
AIM OF THE STUDY Puerarin (Pur) is a primary component of the most functional extracts of Pueraria lobata used in traditional Chinese medicine for centuries. Since it has been postulated that Pur protects the brain against glutamate (Glu) neurotoxicity, we investigated the effects of Pur on Glu-induced axonal transport impairment in primary hippocampal neurons in this study. MATERIALS AND METHODS Primary hippocampal cultures were prepared from 2-day-old Sprague-Dawley rats. Intracellular calcium concentration [Ca(2+)](i), neurofilament (NF) phosphorylation and protein kinase activity for Cdk5 were measured. Time-lapse imaging technology was used to capture the NF axonal transport in the cultured neurons with transiently transfected fluorescence protein linked to the N-terminus of NF-M (EGFP-NFM). RESULTS The results showed that Pur significantly diminished the Glu-induced elevation of [Ca(2+)](i) in dose-dependent manner and antagonized the Glu-evoked increases in NF phosphorylation at protein levels. The neurons under the Glu treatment displayed the accumulation of immobile NF clusters in the cell body and the reduced rates of axonal transport of NFs by 72.8% compared to the control neurons. Intriguingly, Pur reversed the slowed rate of the axonal transport by 35.6%. Pur also remarkably attenuated Glu-evoked activation of Cdk5. CONCLUSIONS Pur may play a role in protecting against Glu-induced NF axonal transport impairment in rat primary hippocampal neurons by inhibiting the increased [Ca(2+)](i) and by impeding the activation of Cdk5.
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Affiliation(s)
- Jie Zhou
- Department of Biochemistry and Molecular Biology, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China
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38
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Chen A, McEwen ML, Sun S, Ravikumar R, Springer JE. Proteomic and phosphoproteomic analyses of the soluble fraction following acute spinal cord contusion in rats. J Neurotrauma 2010; 27:263-74. [PMID: 19691422 DOI: 10.1089/neu.2009.1051] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Traumatic spinal cord injury (SCI) causes marked neuropathological changes in the spinal cord, resulting in limited functional recovery. Currently, there are no effective treatments, and the mechanisms underlying these neuropathological changes are not completely understood. In this study, two-dimensional gel electrophoresis coupled with mass spectrometry was used to investigate injury-related changes in the abundance (SYPRO Ruby stain) and phosphorylation (Pro-Q Diamond stain) of proteins from the soluble fraction of the lesion epicenter at 24 h following SCI. Over 1500 SYPRO Ruby-stained spots and 100 Pro-Q Diamond-stained spots were examined. We identified 26 unique proteins within 38 gel spots that differentially changed in abundance, phosphorylation, or both in response to SCI. Protein redundancies among the gel spots were likely due to differences in proteolysis, post-translational modifications, and the existence of isoforms. The proteins affected were blood-related proteins, heat-shock proteins, glycolytic enzymes, antioxidants, and proteins that function in cell structure, cell signaling, DNA damage, and protein degradation. These protein changes post injury may suggest additional avenues of investigation into the underlying molecular mechanisms responsible for the pathophysiological consequences of SCI.
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Affiliation(s)
- Anshu Chen
- University of Kentucky, Department of Physical Medicine and Rehabilitation, Lexington, Kentucky 40536-0509, USA
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Tonnaer ELGM, Peters TA, Curfs JHAJ. Neurofilament localization and phosphorylation in the developing inner ear of the rat. Hear Res 2010; 267:27-35. [PMID: 20430081 DOI: 10.1016/j.heares.2010.03.090] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/01/2009] [Revised: 03/24/2010] [Accepted: 03/25/2010] [Indexed: 01/27/2023]
Abstract
Detailed understanding of neurofilament protein distribution in the inner ear can shed light on regulatory mechanisms involved in neuronal development of this tissue. We assessed the spatio-temporal changes in the distribution of neurofilaments in the developing rat inner ear between embryonic day 12 and 30 days after birth, using antibodies against phosphorylated as well as non-phosphorylated light (NFL), medium (NFM) and heavy (NFH) neurofilament subunits. Our results show that during development, the onset of neurofilament expression in the rat inner ear is on embryonic day 12, earlier than previously shown. We demonstrate that neurofilament subunits of different molecular weight emerge in a developmental stage-dependent order. In addition, we determined that neurofilaments of the vestibular nerve mature earlier than neurofilaments of the cochlear nerve. Cochlear neurofilament maturation progresses in a gradient from base to apex, and from inner to outer hair cells. The sequential pattern of neurofilament expression we describe may help understand the consequences of certain mutations, and contribute to develop therapeutic strategies.
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Affiliation(s)
- Edith L G M Tonnaer
- Radboud University Nijmegen Medical Center, Department of Otorhinolaryngology, Head & Neck Surgery, Donders Institute for Brain, Cognition and Behaviour, Center for Neuroscience, Philips van Leydenlaan 15, P.O. Box 9101, 6500 HB Nijmegen, The Netherlands.
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40
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Abstract
Neurodegenerative diseases are characterized by progressive dysfunction of specific populations of neurons, determining clinical presentation. Neuronal loss is associated with extra and intracellular accumulation of misfolded proteins, the hallmarks of many neurodegenerative proteinopathies. Major basic processes include abnormal protein dynamics due to deficiency of the ubiquitin-proteosome-autophagy system, oxidative stress and free radical formation, mitochondrial dysfunction, impaired bioenergetics, dysfunction of neurotrophins, 'neuroinflammatory' processes and (secondary) disruptions of neuronal Golgi apparatus and axonal transport. These interrelated mechanisms lead to programmed cell death is a long run over many years. Neurodegenerative disorders are classified according to known genetic mechanisms or to major components of protein deposits, but recent studies showed both overlap and intraindividual diversities between different phenotypes. Synergistic mechanisms between pathological proteins suggest common pathogenic mechanisms. Animal models and other studies have provided insight into the basic neurodegeneration and cell death programs, offering new ways for future prevention/treatment strategies.
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Affiliation(s)
- Kurt A Jellinger
- Institute of Clinical Neurobiology, Kenyongasse, Vienna, Austria.
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Jellinger KA. Recent advances in our understanding of neurodegeneration. J Neural Transm (Vienna) 2009; 116:1111-62. [DOI: 10.1007/s00702-009-0240-y] [Citation(s) in RCA: 160] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2009] [Accepted: 05/05/2009] [Indexed: 12/12/2022]
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42
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Stevenson A, Yates DM, Manser C, De Vos KJ, Vagnoni A, Leigh PN, McLoughlin DM, Miller CCJ. Riluzole protects against glutamate-induced slowing of neurofilament axonal transport. Neurosci Lett 2009; 454:161-4. [PMID: 19429076 DOI: 10.1016/j.neulet.2009.02.061] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2009] [Revised: 02/26/2009] [Accepted: 02/26/2009] [Indexed: 10/21/2022]
Abstract
Riluzole is the only drug approved for the treatment of amyotrophic lateral sclerosis (ALS) but its precise mode of action is not properly understood. Damage to axonal transport of neurofilaments is believed to be part of the pathogenic mechanism in ALS and this has been linked to defective glutamate handling and increased phosphorylation of neurofilament side-arm domains. Here, we show that riluzole protects against glutamate-induced slowing of neurofilament transport. Protection is associated with decreased neurofilament side-arm phosphorylation and inhibition of the activities of two neurofilament kinases, ERK and p38 that are activated in ALS. Thus, the anti-glutamatergic properties of riluzole include protection against glutamate-induced changes to neurofilament phosphorylation and transport.
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Affiliation(s)
- Alison Stevenson
- MRC Centre for Neurodegeneration Research, Institute of Psychiatry, King's College, London, UK
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