651
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Vance C, Rogelj B, Hortobágyi T, De Vos KJ, Nishimura AL, Sreedharan J, Hu X, Smith B, Ruddy D, Wright P, Ganesalingam J, Williams KL, Tripathi V, Al-Saraj S, Al-Chalabi A, Leigh PN, Blair IP, Nicholson G, de Belleroche J, Gallo JM, Miller CC, Shaw CE. Mutations in FUS, an RNA processing protein, cause familial amyotrophic lateral sclerosis type 6. Science 2009; 323:1208-1211. [PMID: 19251628 PMCID: PMC4516382 DOI: 10.1126/science.1165942] [Citation(s) in RCA: 1938] [Impact Index Per Article: 129.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease that is familial in 10% of cases. We have identified a missense mutation in the gene encoding fused in sarcoma (FUS) in a British kindred, linked to ALS6. In a survey of 197 familial ALS index cases, we identified two further missense mutations in eight families. Postmortem analysis of three cases with FUS mutations showed FUS-immunoreactive cytoplasmic inclusions and predominantly lower motor neuron degeneration. Cellular expression studies revealed aberrant localization of mutant FUS protein. FUS is involved in the regulation of transcription and RNA splicing and transport, and it has functional homology to another ALS gene, TARDBP, which suggests that a common mechanism may underlie motor neuron degeneration.
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Affiliation(s)
- Caroline Vance
- Department of Clinical Neuroscience, King’s College London, Medical Research Council (MRC) Centre for Neurodegeneration Research, Institute of Psychiatry, London SE5 8AF, UK
| | - Boris Rogelj
- Department of Clinical Neuroscience, King’s College London, Medical Research Council (MRC) Centre for Neurodegeneration Research, Institute of Psychiatry, London SE5 8AF, UK
| | - Tibor Hortobágyi
- Department of Clinical Neuroscience, King’s College London, Medical Research Council (MRC) Centre for Neurodegeneration Research, Institute of Psychiatry, London SE5 8AF, UK
| | - Kurt J. De Vos
- Department of Neuroscience, King’s College London, MRC Centre for Neurodegeneration Research, Institute of Psychiatry, London SE5 8AF, UK
| | - Agnes Lumi Nishimura
- Department of Clinical Neuroscience, King’s College London, Medical Research Council (MRC) Centre for Neurodegeneration Research, Institute of Psychiatry, London SE5 8AF, UK
| | - Jemeen Sreedharan
- Department of Clinical Neuroscience, King’s College London, Medical Research Council (MRC) Centre for Neurodegeneration Research, Institute of Psychiatry, London SE5 8AF, UK
| | - Xun Hu
- Department of Clinical Neuroscience, King’s College London, Medical Research Council (MRC) Centre for Neurodegeneration Research, Institute of Psychiatry, London SE5 8AF, UK
| | - Bradley Smith
- Department of Clinical Neuroscience, King’s College London, Medical Research Council (MRC) Centre for Neurodegeneration Research, Institute of Psychiatry, London SE5 8AF, UK
| | - Deborah Ruddy
- Department of Clinical Neuroscience, King’s College London, Medical Research Council (MRC) Centre for Neurodegeneration Research, Institute of Psychiatry, London SE5 8AF, UK
| | - Paul Wright
- Department of Clinical Neuroscience, King’s College London, Medical Research Council (MRC) Centre for Neurodegeneration Research, Institute of Psychiatry, London SE5 8AF, UK
| | - Jeban Ganesalingam
- Department of Clinical Neuroscience, King’s College London, Medical Research Council (MRC) Centre for Neurodegeneration Research, Institute of Psychiatry, London SE5 8AF, UK
| | - Kelly L. Williams
- Northcott Neuroscience Laboratory, Australian and New Zealand Army Corps (ANZAC) Research Institute, Concord, NSW 2139, Australia
| | - Vineeta Tripathi
- Department of Clinical Neuroscience, King’s College London, Medical Research Council (MRC) Centre for Neurodegeneration Research, Institute of Psychiatry, London SE5 8AF, UK
| | - Safa Al-Saraj
- Department of Clinical Neuroscience, King’s College London, Medical Research Council (MRC) Centre for Neurodegeneration Research, Institute of Psychiatry, London SE5 8AF, UK
| | - Ammar Al-Chalabi
- Department of Clinical Neuroscience, King’s College London, Medical Research Council (MRC) Centre for Neurodegeneration Research, Institute of Psychiatry, London SE5 8AF, UK
| | - P. Nigel Leigh
- Department of Clinical Neuroscience, King’s College London, Medical Research Council (MRC) Centre for Neurodegeneration Research, Institute of Psychiatry, London SE5 8AF, UK
| | - Ian P. Blair
- Northcott Neuroscience Laboratory, Australian and New Zealand Army Corps (ANZAC) Research Institute, Concord, NSW 2139, Australia
- Faculty of Medicine, University of Sydney, Sydney, NSW 2139, Australia
| | - Garth Nicholson
- Northcott Neuroscience Laboratory, Australian and New Zealand Army Corps (ANZAC) Research Institute, Concord, NSW 2139, Australia
- Molecular Medicine Laboratory, Concord Hospital, Concord, NSW 2139, Australia
- Faculty of Medicine, University of Sydney, Sydney, NSW 2139, Australia
| | - Jackie de Belleroche
- Division of Neurosciences and Mental Health, Faculty of Medicine, Imperial College London, Hammersmith Hospital, London W12 0NN, UK
| | - Jean-Marc Gallo
- Department of Clinical Neuroscience, King’s College London, Medical Research Council (MRC) Centre for Neurodegeneration Research, Institute of Psychiatry, London SE5 8AF, UK
| | - Christopher C. Miller
- Department of Clinical Neuroscience, King’s College London, Medical Research Council (MRC) Centre for Neurodegeneration Research, Institute of Psychiatry, London SE5 8AF, UK
- Department of Neuroscience, King’s College London, MRC Centre for Neurodegeneration Research, Institute of Psychiatry, London SE5 8AF, UK
| | - Christopher E. Shaw
- Department of Clinical Neuroscience, King’s College London, Medical Research Council (MRC) Centre for Neurodegeneration Research, Institute of Psychiatry, London SE5 8AF, UK
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652
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McCluskey LF, Elman LB, Martinez-Lage M, Van Deerlin V, Yuan W, Clay D, Siderowf A, Trojanowski JQ. Amyotrophic lateral sclerosis-plus syndrome with TAR DNA-binding protein-43 pathology. ACTA ACUST UNITED AC 2009; 66:121-4. [PMID: 19139310 DOI: 10.1001/archneur.66.1.121] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
BACKGROUND Amyotrophic lateral sclerosis (ALS)-Plus syndromes meet clinical criteria for ALS but also include 1 or more additional features such as dementia, geographic clustering, extrapyramidal signs, objective sensory loss, autonomic dysfunction, cerebellar degeneration, or ocular motility disturbance. METHODS We performed a whole-brain and spinal cord pathologic analysis in a patient with an ALS-Plus syndrome that included repetitive behaviors along with extrapyramidal and supranuclear ocular motility disturbances resembling the clinical phenotype of progressive supranuclear palsy. RESULTS There was motoneuron cell loss and degeneration of the corticospinal tracts. Bunina bodies were present. TAR DNA-binding protein-43 pathology was diffuse. Significant tau pathology was absent. CONCLUSIONS TAR DNA-binding protein-43 disorders can produce a clinical spectrum of neurodegeneration that includes ALS, frontotemporal lobar degeneration, and ALS with frontotemporal lobar degeneration. The present case illustrates that isolated TAR DNA-binding protein-43 disorders can produce an ALS-Plus syndrome with extrapyramidal features and supranuclear gaze palsy resembling progressive supranuclear palsy.
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Affiliation(s)
- Leo F McCluskey
- Department of Neurology, University of Pennsylvania School of Medicine, 330 S 9th St, Philadelphia, PA 19107, USA.
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653
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Mimicking aspects of frontotemporal lobar degeneration and Lou Gehrig's disease in rats via TDP-43 overexpression. Mol Ther 2009; 17:607-13. [PMID: 19223871 DOI: 10.1038/mt.2009.3] [Citation(s) in RCA: 67] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
Since the discovery of neuropathological lesions made of TDP-43 and ubiquitin proteins in cases of frontotemporal lobar degeneration (FTLD) and amyotrophic lateral sclerosis (ALS), there is a burst of effort on finding related familial mutations and developing animal models. We used an adeno-associated virus (AAV) vector for human TDP-43 expression targeted to the substantia nigra (SN) of rats. Though TDP-43 was expressed mainly in neuronal nuclei as expected, it was also expressed in the cytoplasm, and dotted along the plasma membrane of neurons. Cytoplasmic staining was both diffuse and granular, indicative of preinclusion lesions, over 4 weeks. Ubiquitin deposited in the cytoplasm, specifically in the TDP-43 group, and staining for microglia was increased dose-dependently by 1-2 logs in the TDP-43 group, while neurons were selectively obliterated. Neuronal death induced by TDP-43 was pyknotic and apoptotic. TDP-43 gene transfer caused loss of dopaminergic neurons in the SN and their axons in the striatum. Behavioral motor dysfunction resulted after TDP-43 gene transfer that was vector dose-dependent and progressive over time. The cytoplasmic expression, ubiquitination, and neurodegeneration mimicked features of the TDP-43 diseases, and the gliosis, apoptosis, and motor impairment may also be relevant to TDP-43 disease forms involving nigrostriatal degeneration.
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654
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Abstract
Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease characterised by progressive muscular paralysis reflecting degeneration of motor neurones in the primary motor cortex, corticospinal tracts, brainstem and spinal cord. Incidence (average 1.89 per 100,000/year) and prevalence (average 5.2 per 100,000) are relatively uniform in Western countries, although foci of higher frequency occur in the Western Pacific. The mean age of onset for sporadic ALS is about 60 years. Overall, there is a slight male prevalence (M:F ratio approximately 1.5:1). Approximately two thirds of patients with typical ALS have a spinal form of the disease (limb onset) and present with symptoms related to focal muscle weakness and wasting, where the symptoms may start either distally or proximally in the upper and lower limbs. Gradually, spasticity may develop in the weakened atrophic limbs, affecting manual dexterity and gait. Patients with bulbar onset ALS usually present with dysarthria and dysphagia for solid or liquids, and limbs symptoms can develop almost simultaneously with bulbar symptoms, and in the vast majority of cases will occur within 1-2 years. Paralysis is progressive and leads to death due to respiratory failure within 2-3 years for bulbar onset cases and 3-5 years for limb onset ALS cases. Most ALS cases are sporadic but 5-10% of cases are familial, and of these 20% have a mutation of the SOD1 gene and about 2-5% have mutations of the TARDBP (TDP-43) gene. Two percent of apparently sporadic patients have SOD1 mutations, and TARDBP mutations also occur in sporadic cases. The diagnosis is based on clinical history, examination, electromyography, and exclusion of 'ALS-mimics' (e.g. cervical spondylotic myelopathies, multifocal motor neuropathy, Kennedy's disease) by appropriate investigations. The pathological hallmarks comprise loss of motor neurones with intraneuronal ubiquitin-immunoreactive inclusions in upper motor neurones and TDP-43 immunoreactive inclusions in degenerating lower motor neurones. Signs of upper motor neurone and lower motor neurone damage not explained by any other disease process are suggestive of ALS. The management of ALS is supportive, palliative, and multidisciplinary. Non-invasive ventilation prolongs survival and improves quality of life. Riluzole is the only drug that has been shown to extend survival.
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Affiliation(s)
- Lokesh C Wijesekera
- MRC centre for Neurodegeneration Research, Department of Clinical Neuroscience, Box 41, Institute of Psychiatry, Kings College London, London, SE5 8AF, UK
| | - P Nigel Leigh
- MRC centre for Neurodegeneration Research, Department of Clinical Neuroscience, Box 41, Institute of Psychiatry, Kings College London, London, SE5 8AF, UK
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655
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Fujishiro H, Uchikado H, Arai T, Hasegawa M, Akiyama H, Yokota O, Tsuchiya K, Togo T, Iseki E, Hirayasu Y. Accumulation of phosphorylated TDP-43 in brains of patients with argyrophilic grain disease. Acta Neuropathol 2009; 117:151-8. [PMID: 19039597 DOI: 10.1007/s00401-008-0463-2] [Citation(s) in RCA: 82] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2008] [Revised: 11/18/2008] [Accepted: 11/18/2008] [Indexed: 12/12/2022]
Abstract
To determine whether TAR-DNA binding protein 43 (TDP-43) immunoreactivity was present in brains of argyrophilic grain disease (AGD), we immunohistochemically examined 15 cases of AGD (mean age at death: 84 years) using a panel of anti-TDP-43 antibodies, including both phosphorylation-independent and -dependent ones. Nine AGD cases (60%) showed TDP-43 immunoreactivities mainly in the limbic regions and lateral occipitotemporal cortex. TDP-43 positive structures included neuronal cytoplasmic inclusions, dystrophic neurites, glial cytoplasmic inclusions, grain-like dot-shaped structures, and neurofibrillary tangle (NFT)-like structures. The distribution of these TDP-43 positive structures was largely consistent with that of argyrophilic grains. Double-labeling confocal microscopy revealed, however, that many of phospho-TDP-43 positive structures were not colocalized with phospho-tau staining. Colocalization of phospho-TDP-43 and phospho-tau was observed only in part of neuronal cytoplasmic inclusions, grain-like structures and NFT-like structures. There were no differences in demographics, disease duration, brain weight, NFT Braak stage, or severity of amyloid burden between AGD cases with and without TDP-43-immunoreactivity. However, cases of AGD with TDP-43-immunoreactivity were assigned to higher AGD stages than those without TDP-43-immunoreactivity (P < 0.05). Furthermore, the TDP-43 pathology tended to be prominent in cases with severe grain pathology. The results of the present study indicate for the first time a high frequency of concomitant TDP-43 pathology in AGD, and suggest that abnormal accumulation of TDP-43 may be involved in the pathological process and disease progression of AGD.
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Affiliation(s)
- Hiroshige Fujishiro
- Department of Psychogeriatrics, Tokyo Institute of Psychiatry, 2-1-8 Kamikitazawa, Setagaya-ku, Tokyo 156-8585, Japan
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656
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Neumann M, Kwong LK, Lee EB, Kremmer E, Flatley A, Xu Y, Forman MS, Troost D, Kretzschmar HA, Trojanowski JQ, Lee VMY. Phosphorylation of S409/410 of TDP-43 is a consistent feature in all sporadic and familial forms of TDP-43 proteinopathies. Acta Neuropathol 2009; 117:137-49. [PMID: 19125255 DOI: 10.1007/s00401-008-0477-9] [Citation(s) in RCA: 424] [Impact Index Per Article: 28.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2008] [Revised: 12/22/2008] [Accepted: 12/22/2008] [Indexed: 12/12/2022]
Abstract
Accumulation of hyperphosphorylated, ubiquitinated and N-terminally truncated TAR DNA-binding protein (TDP-43) is the pathological hallmark lesion in most familial and sporadic forms of FTLD-U and ALS, which can be subsumed as TDP-43 proteinopathies. In order to get more insight into the role of abnormal phosphorylation in the disease process, the identification of specific phosphorylation sites and the generation of phosphorylation-specific antibodies are mandatory. Here, we developed and characterized novel rat monoclonal antibodies (1D3 and 7A9) raised against phosphorylated S409/410 of TDP-43. These antibodies were used to study the presence of S409/410 phosphorylation by immunohistochemistry and biochemical analysis in a large series of 64 FTLD-U cases with or without motor neuron disease including familial cases with mutations in progranulin (n = 5), valosin-containing protein (n = 4) and linkage to chromosome 9p (n = 4), 18 ALS cases as well as other neurodegenerative diseases with concomitant TDP-43 pathology (n = 5). Our data demonstrate that phosphorylation of S409/410 of TDP-43 is a highly consistent feature in pathologic inclusions in the whole spectrum of sporadic and familial forms of TDP-43 proteinopathies. Physiological nuclear TDP-43 was not detectable with these mAbs by immunohistochemistry and by immunoblot analyses. While the accumulation of phosphorylated C-terminal fragments was a robust finding in the cortical brain regions of FTLD-U and ALS, usually being much more abundant than the phosphorylated full-length TDP-43 band, spinal cord samples revealed a predominance of full-length TDP-43 over C-terminal fragments. This argues for a distinct TDP-43 species composition in inclusions in cortical versus spinal cord cells. Overall, these mAbs are powerful tools for the highly specific detection of disease-associated abnormal TDP-43 species and will be extremely useful for the neuropathological routine diagnostics of TDP-43 proteinopathies and for the investigation of emerging cellular and animal models for TDP-43 proteinopathies.
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Affiliation(s)
- Manuela Neumann
- Institute of Neuropathology, University Hospital of Zürich, Schmelzbergstr. 12, 8091 Zurich, Switzerland.
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657
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Arai T, Mackenzie IRA, Hasegawa M, Nonoka T, Niizato K, Tsuchiya K, Iritani S, Onaya M, Akiyama H. Phosphorylated TDP-43 in Alzheimer's disease and dementia with Lewy bodies. Acta Neuropathol 2009; 117:125-36. [PMID: 19139911 DOI: 10.1007/s00401-008-0480-1] [Citation(s) in RCA: 262] [Impact Index Per Article: 17.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2008] [Revised: 12/29/2008] [Accepted: 12/29/2008] [Indexed: 12/12/2022]
Abstract
Phosphorylated and proteolytically cleaved TDP-43 is a major component of the ubiquitin-positive inclusions in the most common pathological subtype of frontotemporal lobar degeneration (FTLD-U). Intracellular accumulation of TDP-43 is observed in a subpopulation of patients with other dementia disorders, including Alzheimer's disease (AD) and dementia with Lewy bodies (DLB). However, the pathological significance of TDP-43 pathology in these disorders is unknown, since biochemical features of the TDP-43 accumulated in AD and DLB brains, especially its phosphorylation sites and pattern of fragmentation, are still unclear. To address these issues, we performed immunohistochemical and biochemical analyses of AD and DLB cases, using phosphorylation-dependent anti-TDP-43 antibodies. We found a higher frequency of pathological TDP-43 in AD (36-56%) and in DLB (53-60%) than previously reported. Of the TDP-43-positive cases, about 20-30% showed neocortical TDP-43 pathology resembling the FTLD-U subtype associated with progranulin gene (PGRN) mutations. Immunoblot analyses of the sarkosyl-insoluble fraction from cases with neocortical TDP-43 pathology showed intense staining of several low-molecular-weight bands, corresponding to C-terminal fragments of TDP-43. Interestingly, the band pattern of these C-terminal fragments in AD and DLB also corresponds to that previously observed in the FTLD-U subtype associated with PGRN mutations. These results suggest that the morphological and biochemical features of TDP-43 pathology are common between AD or DLB and a specific subtype of FTLD-U. There may be genetic factors, such as mutations or genetic variants of PGRN underlying the co-occurrence of abnormal deposition of TDP-43, tau and alpha-synuclein.
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Affiliation(s)
- Tetsuaki Arai
- Department of Psychogeriatrics, Tokyo Institute of Psychiatry, Tokyo Metropolitan Organization for Medical Research, 2-1-8 Kamikitazawa, Setagaya-ku, Tokyo 156-8585, Japan.
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658
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Neumann M. Molecular neuropathology of TDP-43 proteinopathies. Int J Mol Sci 2009; 10:232-246. [PMID: 19333444 PMCID: PMC2662455 DOI: 10.3390/ijms10010232] [Citation(s) in RCA: 104] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2008] [Revised: 01/06/2009] [Accepted: 01/08/2009] [Indexed: 12/12/2022] Open
Abstract
The identification of TDP-43 as the major component of the pathologic inclusions in most forms of sporadic and familial frontotemporal lobar degeneration with ubiquitin-positive inclusions (FTLD-U) and amyotrophic lateral sclerosis (ALS) resolved a long-standing enigma concerning the nature of the ubiquitinated disease protein under these conditions. Anti-TDP-43 immunohistochemistry and the recent development of novel tools, such as phosphorylation-specific TDP-43 antibodies, have increased our knowledge about the spectrum of pathological changes associated with FTLD-U and ALS and moreover, facilitated the neuropathological routine diagnosis of these conditions. This review summarizes the recent advances in our understanding on the molecular neuropathology and pathobiology of TDP-43 in FTLD and ALS.
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Affiliation(s)
- Manuela Neumann
- Institute of Neuropathology, University Hospital of Zurich, Schmelzbergstr. 12, 8091 Zurich, Switzerland
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659
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Buratti E, Baralle FE. The molecular links between TDP-43 dysfunction and neurodegeneration. ADVANCES IN GENETICS 2009; 66:1-34. [PMID: 19737636 DOI: 10.1016/s0065-2660(09)66001-6] [Citation(s) in RCA: 76] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
TDP-43 nuclear protein is involved in several major neurodegenerative diseases that include frontotemporal lobar degeneration with ubiquitin (FTLD-U) bodies and amyotrophic lateral sclerosis (ALS). As a consequence, the role played by this protein in both normal and diseased cellular metabolism has come under very close scrutiny. In the neuronal tissues of affected individuals TDP-43 undergoes aberrant localization to the cytoplasm to form insoluble aggregates. Furthermore, it is subject to degradation, ubiquitination, and phosphorylation. Understanding the pathways that lead to these changes will be crucial to define the functional role played by this protein in disease. Several recent biochemical and molecular studies have provided new information regarding the potential physiological consequences of these modifications. Moreover, the discovery of TDP-43 mutations associated with disease in a limited number of cases and the data from existing animal models have strengthened the proposed links between this protein and disease. In this review we will discuss the available data regarding the biochemical and functional changes that transform the wild-type endogenous TDP-43 in its pathological form. Furthermore, we will concentrate on examining the potential pathological mechanisms mediated by TDP-43 in different gain- versus loss-of-function scenarios. In the near future, this knowledge will hopefully increase our knowledge on disease progression and development. Moreover, it will allow the design of innovative therapeutic strategies for these pathologies based on the specific molecular defects causing the disease.
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Affiliation(s)
- Emanuele Buratti
- International Centre for Genetic Engineering and Biotechnology (ICGEB), Trieste, Italy
| | - Francisco E Baralle
- International Centre for Genetic Engineering and Biotechnology (ICGEB), Trieste, Italy
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660
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Kasai T, Tokuda T, Ishigami N, Sasayama H, Foulds P, Mitchell DJ, Mann DMA, Allsop D, Nakagawa M. Increased TDP-43 protein in cerebrospinal fluid of patients with amyotrophic lateral sclerosis. Acta Neuropathol 2009; 117:55-62. [PMID: 18989684 DOI: 10.1007/s00401-008-0456-1] [Citation(s) in RCA: 161] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2008] [Revised: 10/28/2008] [Accepted: 10/28/2008] [Indexed: 12/14/2022]
Abstract
There is mounting pathological, biochemical and genetic evidence that the metabolism and aggregation of the 43-kDa transactive response (TAR)-DNA-binding protein (TDP-43) play a crucial role in the pathogenesis of sporadic and some forms of familial amyotrophic lateral sclerosis (ALS). Recently, it was reported using an ELISA system that elevated levels of TDP-43 were detected in plasma samples from patients with Alzheimer's disease and frontotemporal dementia, compared to healthy controls. To determine whether quantification of TDP-43 in cerebrospinal fluid (CSF) is potentially informative in the diagnosis of ALS, we measured the concentration, by a similar ELISA method, of TDP-43 in CSF from 30 patients with ALS (diagnosed according to the revised El Escorial criteria) and 29 age-matched control patients without any neurodegenerative disease. We found that, as a group, the ALS patients had significantly higher levels of TDP-43 in their CSF than the age-matched controls (6.92 +/- 3.71 ng/ml in ALS versus 5.31 +/- 0.94 ng/ml in controls, p < 0.05), with levels of TDP-43 in CSF elevated beyond 95% upper confidence level for the control group in six (20%) of the patients with sporadic ALS. All the six patients with higher levels of CSF TDP-43 were examined within 10 months of the onset of illness. The patients examined within 10 months of onset showed significantly higher levels of CSF TDP-43 (8.24 +/- 4.72 ng/ml) than those examined after 11 months or more of onset (5.41 +/- 0.66 ng/ml, p < 0.05). These results suggest that the levels of TDP-43 in CSF may increase in the early stage of ALS. We also confirmed the existence of the TDP-43 protein in CSF from some patients with ALS, and a control subject, by western blotting of proteins immunocaptured from the CSF samples. Raised TDP-43 levels in the CSF may preempt the formation of TDP-43 pathology in the central nervous system, or correlate with early-stage TDP-43 pathology, and accordingly be a biomarker for the early stage of ALS.
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Affiliation(s)
- Takashi Kasai
- Department of Neurology, Kyoto Prefectural University of Medicine, 465 Kajii-cho, Kamigyo-ku, Kyoto, 602-0841, Japan
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661
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Wobbler mice modeling motor neuron disease display elevated transactive response DNA binding protein. Neuroscience 2009; 158:745-50. [DOI: 10.1016/j.neuroscience.2008.10.030] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2008] [Revised: 10/14/2008] [Accepted: 10/16/2008] [Indexed: 12/12/2022]
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662
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Kishikawa H, Wu D, Hu GF. Targeting angiogenin in therapy of amyotropic lateral sclerosis. Expert Opin Ther Targets 2008; 12:1229-42. [PMID: 18781822 DOI: 10.1517/14728222.12.10.1229] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
BACKGROUND Missense heterozygous mutations in the coding region of angiogenin (ANG) gene, encoding a 14 kDa angiogenic RNase, were recently found in patients of amyotropic lateral sclerosis (ALS). Functional analyses have shown that these are loss-of-function mutations, implying that angiogenin deficiency is associated with ALS pathogenesis and that increasing ANG expression or angiogenin activity could be a novel approach for ALS therapy. OBJECTIVE Review the evidence showing the involvement of angiogenin in motor neuron physiology and function, and provide a rationale for targeting angiogenin in ALS therapy. METHODS Review the current understanding of the mechanism of angiogenin action in connection with ALS genetics, pathogenesis and therapy. CONCLUSION ANG is the first gene whose loss-of-function mutations are associated with ALS pathogenesis. Therapeutic modulation of angiogenin level and activity in the spinal cord, either by systemic delivery of angiogenin protein or through retrograde transport of ANG-encoding viral particles, may be beneficial for ALS patients.
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Affiliation(s)
- Hiroko Kishikawa
- Harvard Medical School, Department of Pathology, 77 Avenue Louis Pasteur, Boston, MA 02115, USA
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663
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Nuclear erythroid 2-related factor 2-antioxidative response element signaling pathway in motor cortex and spinal cord in amyotrophic lateral sclerosis. J Neuropathol Exp Neurol 2008; 67:1055-62. [PMID: 18957896 DOI: 10.1097/nen.0b013e31818b4906] [Citation(s) in RCA: 113] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
Oxidative stress and inflammation are important pathogenetic mechanisms in amyotrophic lateral sclerosis (ALS). Nuclear erythroid 2-related factor 2 (Nrf2) is a basic region leucine-zipper transcription factor that binds to the antioxidant response element, thereby regulating the expression of many genes that are involved in cellular antioxidant and anti-inflammatory defense. Under normal conditions, Nrf2 activation is inhibited by Kelch-like ECH-associated protein 1 (Keap1). We investigated the potential involvement of the Nrf2/antioxidant response element signaling pathway in the selective degeneration of motor neurons in ALS. Nrf2 and Keap1 expression was analyzed in primary motor cortex and spinal cord postmortem tissue samples from ALS patients and controls by in situ hybridization histochemistry, quantitative real-time polymerase chain reaction, immunohistochemistry, and Western blot analysis. In ALS samples, there was a reduction of Nrf2 mRNA and protein expression in neurons, whereas Keap1 mRNA expression was increased in the motor cortex. These results suggest that alterations in this signaling cascade occur in motor neurons in ALS and that they may contribute to chronic motor neuron degeneration.
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664
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van der Graaff MM, de Jong JMBV, Baas F, de Visser M. Upper motor neuron and extra-motor neuron involvement in amyotrophic lateral sclerosis: a clinical and brain imaging review. Neuromuscul Disord 2008; 19:53-8. [PMID: 19070491 DOI: 10.1016/j.nmd.2008.10.002] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2008] [Revised: 09/25/2008] [Accepted: 10/05/2008] [Indexed: 11/17/2022]
Abstract
There is an ongoing discussion whether ALS is primarily a disease of upper motor neurons or lower motor neurons. We undertook a review to assess how new insights have contributed to solve this controversy. For this purpose we selected relevant publications from 1995 onwards focussing on (1) primary targets and disease progression in ALS and variants of ALS, (2) brain imaging markers for upper motor neuron lesion, and (3) evidence for ALS being a multisystem disorder. Clinically, upper motor and lower motor neuron symptoms can occur in any order over time. Brain imaging markers show upper motor neuron involvement in early disease. Overlap syndromes of ALS and dementia, and involvement of autonomic and sensory nerves occur frequently. PET/SPECT scans, functional MRI and voxel based morphometry studies clearly show abnormalities in extra-motor areas of the brain. Pathologically, the 43 kDa TAR DNA-binding protein (TDP-43) provides a clue to these overlapping disorders. In conclusion, evidence accumulates that ALS is a multisystem disorder rather than a pure lower and/or upper motor neuron disorder.
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Affiliation(s)
- M M van der Graaff
- Department of Neurology, Academic Medical Centre, P.O. Box 22660, 1100 DD Amsterdam, The Netherlands.
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665
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Steinacker P, Hendrich C, Sperfeld AD, Jesse S, von Arnim CAF, Lehnert S, Pabst A, Uttner I, Tumani H, Lee VMY, Trojanowski JQ, Kretzschmar HA, Ludolph A, Neumann M, Otto M. TDP-43 in cerebrospinal fluid of patients with frontotemporal lobar degeneration and amyotrophic lateral sclerosis. ACTA ACUST UNITED AC 2008; 65:1481-7. [PMID: 19001167 DOI: 10.1001/archneur.65.11.1481] [Citation(s) in RCA: 152] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
BACKGROUND Recently, TAR DNA-binding protein 43 (TDP-43) was identified as the major component of ubiquitin-positive tau-negative neuronal and glial inclusions in the most common form of frontotemporal lobar degeneration (FTLD) and in amyotrophic lateral sclerosis (ALS). It was demonstrated that different TDP-43 profiles correspond to clinical phenotypes of FTLD or ALS subgroups, and the differential diagnostic potential of TDP-43 was suggested. OBJECTIVES To examine TDP-43 in cerebrospinal fluid (CSF) and to analyze whether it could serve as a diagnostic marker. DESIGN We characterized CSF TDP-43 by immunoblot using different TDP-43 antibodies and determined the relative TDP-43 levels in CSF samples from patients. SETTING Academic research. PATIENTS Twelve patients with FTLD, 15 patients with ALS, 9 patients with ALS plus FTLD, 3 patients with ALS plus additional signs of frontal disinhibition, and 13 control subjects. MAIN OUTCOME MEASURES Results of TDP-43 immunoblot. RESULTS Polyclonal TDP-43 antibodies recognized a 45-kDa band in all analyzed samples. Two monoclonal and N-terminus-specific antibodies did not detect any specific bands, but C-terminus-specific antibodies detected a 45-kDa band and additional bands at approximately 20 kDa in all CSF samples. Relative quantification of 45-kDa bands revealed significant differences among the diagnostic groups (P =.046). Specifically, patients with ALS (P =.03) and FTLD (P =.02) had higher TDP-43 levels than controls but with a prominent overlap of values. CONCLUSION Although there is no evidence of pathologically altered TDP-43 proteins in CSF, TDP-43 levels in CSF might aid in characterizing subgroups of patients across the ALS and FTLD disease spectrum.
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666
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Abstract
Selective involvements of upper and lower motor neurons have been regarded as one of the most characteristic features of amyotrophic lateral sclerosis (ALS). However, evidences of more extensive involvements affecting the systems other than the pure motor systems have been accumulated since the discovery of ubiquitin-positive inclusions (UbIs) in ALS, ALS-dementia (ALS-D), and frontotemporal lobar degeneration (FTLD) with UbIs (FTLD-U). A breakthrough occurred in ALS research in October 2006, when TAR DNA-binding protein43 (TDP-43) was identified as the core protein that is ubiquitinated in the cytoplasm, neurites and nucleus as UbIs. Antibody to phosphorylated TDP-43 selectively reacts to the inclusions and Western blotting demonstrates abnormal bands of phosphorylated TDP-43 in the brains of patients with ALS/FTLD-U. Similar findings were observed in ALS/parkinsonism-dementia complex (PDC) of Guam and Kii peninsula. These diseases are lumped in the "TDP-43 proteinopathy". In early 2008, several mutations of the TDP-43 gene were identified as the causative gene of autosomal-dominant familial ALS without SOD1 gene mutations. These findings suggest that abnormalities of TDP-43 directly or indirectly produce severe motor neuron degeneration. TDP-43 is thus one of the key proteins causing TDP-43 proteinopathies such as ALS, ALS-D, FTLD-U, and ALS/PDC of Guam and Kii. New revolutionary developments on ALS research for molecular mechanism and therapy are expected.
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Affiliation(s)
- Shigeki Kuzuhara
- Department of Neurology, National Center Hospital of Neurology and Psychiatry
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667
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Colocalization of Transactivation-Responsive DNA-Binding Protein 43 and Huntingtin in Inclusions of Huntington Disease. J Neuropathol Exp Neurol 2008; 67:1159-65. [DOI: 10.1097/nen.0b013e31818e8951] [Citation(s) in RCA: 153] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
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668
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Gribkoff VK, Bozik ME. KNS-760704 [(6R)-4,5,6,7-tetrahydro-N6-propyl-2, 6-benzothiazole-diamine dihydrochloride monohydrate] for the treatment of amyotrophic lateral sclerosis. CNS Neurosci Ther 2008; 14:215-26. [PMID: 18801114 DOI: 10.1111/j.1755-5949.2008.00048.x] [Citation(s) in RCA: 62] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Developing effective treatments for chronic neurodegenerative disorders such as amyotrophic lateral sclerosis (ALS) has proven extremely difficult. ALS is universally fatal, characterized by progressive weakness due to the degeneration of upper and lower motor neurons, and leads eventually to respiratory failure which is the usual cause of death. Only a single treatment has been approved, the modestly effective nonspecific neuroprotectant Rilutek (riluzole; 2-amino-6-(trifluoromethoxy)benzothiazole). KNS-760704 [(6R)-4,5,6,7-tetrahydro-N6-propyl-2,6-benzothiazole-diamine dihydrochloride, RPPX], a synthetic amino-benzothiazole with demonstrated activity in maintaining mitochondrial function, is being developed as a treatment for ALS. It has proven to be effective in multiple in vitro and in vivo assays of neuroprotection, including the G93A-SOD1 mutant mouse model; however, its specific mechanism of action remains unknown. The potential of KNS-760604 as a treatment for ALS was first suggested by studies showing that its optical enantiomer, Mirapex[(6S)-4,5,6,7-tetrahydro-N6-propyl-2,6-benzothiazole-diamine; pramipexole dihydrochloride; PPX], a high-affinity agonist at dopamine D2, D3, and D4 receptors, exhibits important neuroprotective properties independent of its dopamine receptor agonism. In cell-based assays, both RPPX and PPX reduce the production of reactive oxygen species (ROS), attenuate the activation of apoptotic pathways, and increase cell survival in response to a variety of neurotoxins. However, PPX has limited utility as a clinical neuroprotective agent because the drug concentrations required for neuroprotection would likely produce unacceptable dopaminergic side effects. RPPX, on the other hand, while possessing the same neuroprotective potential as PPX, is a much lower-affinity dopamine receptor agonist and may therefore be more useful in the treatment of ALS. This review will examine the data supporting the hypothesis that the RPPX may have therapeutic potential for the treatment of neurodegenerative disorders including ALS. In addition, we will briefly review recent preclinical data in support of RPPX, and discuss the current status of its clinical development.
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669
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Isaacs AM, Powell C, Webb TE, Linehan JM, Collinge J, Brandner S. Lack of TAR-DNA binding protein-43 (TDP-43) pathology in human prion diseases. Neuropathol Appl Neurobiol 2008; 34:446-56. [PMID: 18657254 PMCID: PMC2607533 DOI: 10.1111/j.1365-2990.2008.00963.x] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
AIMS TAR-DNA binding protein-43 (TDP-43) is the major ubiquitinated protein in the aggregates in frontotemporal dementia with ubiquitin-positive, tau-negative inclusions and motor neurone disease. Abnormal TDP-43 immunoreactivity has also been described in Alzheimer's disease, Lewy body diseases and Guam parkinsonism-dementia complex. We therefore aimed to determine whether there is TDP-43 pathology in human prion diseases, which are characterised by variable deposition of prion protein (PrP) aggregates in the brain as amyloid plaques or more diffuse deposits. MATERIAL AND METHODS TDP-43, ubiquitin and PrP were analysed by immunohistochemistry and double-labelling immunofluorescence, in sporadic, acquired and inherited forms of human prion disease. RESULTS Most PrP plaques contained ubiquitin, while synaptic PrP deposits were not associated with ubiquitin. No abnormal TDP-43 inclusions were identified in any type of prion disease case, and TDP-43 did not co-localize with ubiquitin-positive PrP plaques or with diffuse PrP aggregates. CONCLUSIONS These data do not support a role for TDP-43 in prion disease pathogenesis and argue that TDP-43 inclusions define a distinct group of neurodegenerative disorders.
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Affiliation(s)
- A M Isaacs
- MRC Prion Unit, UCL Institute of Neurology, London, U.K
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670
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Current world literature. Trauma and rehabilitation. Curr Opin Neurol 2008; 21:762-4. [PMID: 18989123 DOI: 10.1097/wco.0b013e32831cbb85] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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671
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Turner BJ, Bäumer D, Parkinson NJ, Scaber J, Ansorge O, Talbot K. TDP-43 expression in mouse models of amyotrophic lateral sclerosis and spinal muscular atrophy. BMC Neurosci 2008; 9:104. [PMID: 18957104 PMCID: PMC2583980 DOI: 10.1186/1471-2202-9-104] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2008] [Accepted: 10/28/2008] [Indexed: 12/12/2022] Open
Abstract
Background Redistribution of nuclear TAR DNA binding protein 43 (TDP-43) to the cytoplasm and ubiquitinated inclusions of spinal motor neurons and glial cells is characteristic of amyotrophic lateral sclerosis (ALS) pathology. Recent evidence suggests that TDP-43 pathology is common to sporadic ALS and familial ALS without SOD1 mutation, but not SOD1-related fALS cases. Furthermore, it remains unclear whether TDP-43 abnormalities occur in non-ALS forms of motor neuron disease. Here, we characterise TDP-43 localisation, expression levels and post-translational modifications in mouse models of ALS and spinal muscular atrophy (SMA). Results TDP-43 mislocalisation to ubiquitinated inclusions or cytoplasm was notably lacking in anterior horn cells from transgenic mutant SOD1G93A mice. In addition, abnormally phosphorylated or truncated TDP-43 species were not detected in fractionated ALS mouse spinal cord or brain. Despite partial colocalisation of TDP-43 with SMN, depletion of SMN- and coilin-positive Cajal bodies in motor neurons of affected SMA mice did not alter nuclear TDP-43 distribution, expression or biochemistry in spinal cords. Conclusion These results emphasise that TDP-43 pathology characteristic of human sporadic ALS is not a core component of the neurodegenerative mechanisms caused by SOD1 mutation or SMN deficiency in mouse models of ALS and SMA, respectively.
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Affiliation(s)
- Bradley J Turner
- University of Oxford, MRC Functional Genetics Unit, Department of Physiology, Anatomy and Genetics, South Parks Road, Oxford, OX1 3QX, UK.
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672
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Liscic RM, Grinberg LT, Zidar J, Gitcho MA, Cairns NJ. ALS and FTLD: two faces of TDP-43 proteinopathy. Eur J Neurol 2008; 15:772-80. [PMID: 18684309 DOI: 10.1111/j.1468-1331.2008.02195.x] [Citation(s) in RCA: 103] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Major discoveries have been made in the recent past in the genetics, biochemistry and neuropathology of frontotemporal lobar degeneration (FTLD). TAR DNA-binding protein 43 (TDP-43), encoded by the TARDBP gene, has been identified as the major pathological protein of FTLD with ubiquitin-immunoreactive (ub-ir) inclusions (FTLD-U) with or without amyotrophic lateral sclerosis (ALS) and sporadic ALS. Recently, mutations in the TARDBP gene in familial and sporadic ALS have been reported which demonstrate that abnormal TDP-43 alone is sufficient to cause neurodegeneration. Several familial cases of FTLD-U, however, are now known to have mutations in the progranulin (GRN) gene, but granulin is not a component of the TDP-43- and ub-ir inclusions. Further, TDP-43 is found to be a component of the inclusions of an increasing number of neurodegenerative diseases. Other FTLD-U entities with TDP-43 proteinopathy include: FTLD-U with valosin-containing protein (VCP) gene mutation and FTLD with ALS linked to chromosome 9p. In contrast, chromosome 3-linked dementia, FTLD-U with chromatin modifying protein 2B (CHMP2B) mutation, has ub-ir, TDP-43-negative inclusions. In summary, recent discoveries have generated new insights into the pathogenesis of a spectrum of disorders called TDP-43 proteinopathies including: FTLD-U, FTLD-U with ALS, ALS, and a broadening spectrum of other disorders. It is anticipated that these discoveries and a revised nosology of FTLD will contribute toward an accurate diagnosis, and facilitate the development of new diagnostic tests and therapeutics.
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Affiliation(s)
- R M Liscic
- Institute for Medical Research and Occupational Health, Zagreb, Croatia
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673
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Ule J. Ribonucleoprotein complexes in neurologic diseases. Curr Opin Neurobiol 2008; 18:516-23. [PMID: 18929657 DOI: 10.1016/j.conb.2008.09.018] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2008] [Revised: 09/25/2008] [Accepted: 09/29/2008] [Indexed: 12/12/2022]
Abstract
Ribonucleoprotein (RNP) complexes regulate the tissue-specific RNA processing and transport that increases the coding capacity of our genome and the ability to respond quickly and precisely to the diverse set of signals. This review focuses on three proteins that are part of RNP complexes in most cells of our body: TAR DNA-binding protein (TDP-43), the survival motor neuron protein (SMN), and fragile-X mental retardation protein (FMRP). In particular, the review asks the question why these ubiquitous proteins are primarily associated with defects in specific regions of the central nervous system? To understand this question, it is important to understand the role of genetic and cellular environment in causing the defect in the protein, as well as how the defective protein leads to misregulation of specific target RNAs. Two approaches for comprehensive analysis of defective RNA-protein interactions are presented. The first approach defines the RNA code or the collection of proteins that bind to a certain cis-acting RNA site in order to lead to a predictable outcome. The second approach defines the RNA map or the summary of positions on target RNAs where binding of a particular RNA-binding protein leads to a predictable outcome. As we learn more about the RNA codes and maps that guide the action of the dynamic RNP world in our brain, possibilities for new treatments of neurologic diseases are bound to emerge.
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Affiliation(s)
- Jernej Ule
- MRC Laboratory of Molecular Biology, Cambridge, UK.
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674
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Wang IF, Wu LS, Shen CKJ. TDP-43: an emerging new player in neurodegenerative diseases. Trends Mol Med 2008; 14:479-85. [PMID: 18929508 DOI: 10.1016/j.molmed.2008.09.001] [Citation(s) in RCA: 86] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2008] [Revised: 09/01/2008] [Accepted: 09/01/2008] [Indexed: 12/12/2022]
Abstract
Until a couple of years ago, TAR-DNA-binding protein-43 (TDP-43) was a relatively unknown nuclear protein implicated in transcriptional repression and splicing. Since 2006, when the protein was reported to be present in inclusions in the neurons and/or glial cells of a range of neurodegenerative diseases, including amyotrophic lateral sclerosis (ALS), frontotemporal lobar degeneration with ubiquitin-positive, tau- and alpha-synuclein-negative inclusions (FTLD-U) and Alzheimer's disease (AD), many reports on the medical aspects of TDP-43 have been published. Here, we summarize the current literature on TDP-43, focusing on recent studies that provide clues to the function of TDP-43. Using this information and database analysis, we also suggest a molecular and cellular model for possible events in normal and diseased neurons in relation to the emerging importance of the function and dysfunction of this protein as a target for basic as well as translational research.
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Affiliation(s)
- I-Fan Wang
- Institute of Molecular Biology, Academia Sinica, Taipei, Taiwan
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675
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Kühnlein P, Sperfeld AD, Vanmassenhove B, Van Deerlin V, Lee VMY, Trojanowski JQ, Kretzschmar HA, Ludolph AC, Neumann M. Two German kindreds with familial amyotrophic lateral sclerosis due to TARDBP mutations. ACTA ACUST UNITED AC 2008; 65:1185-9. [PMID: 18779421 DOI: 10.1001/archneur.65.9.1185] [Citation(s) in RCA: 121] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
BACKGROUND Abnormal neuronal inclusions composed of the transactivation response DNA-binding protein 43 (TDP-43) are characteristic neuropathologic lesions in sporadic and familial forms of amyotrophic lateral sclerosis (ALS). This makes TARDBP, the gene encoding for TDP-43, a candidate for genetic screening in ALS. OBJECTIVES To investigate the presence and frequency of TARDBP mutations in ALS. DESIGN Genetic analysis. SETTING Academic research. PARTICIPANTS One hundred thirty-four patients with sporadic ALS, 31 patients with familial non-superoxide dismutase 1 gene (non-SOD1) (OMIM 147450) ALS, and 400 healthy control subjects. MAIN OUTCOME MEASURES We identified 2 missense mutations (G348C and the novel N352S) in TARDBP in 2 small kindreds with a hereditary form of ALS with early spinal onset resulting in fatal respiratory insufficiency without clinical relevant bulbar symptoms or signs of cognitive impairment. RESULTS The mutations located in the C-terminus of TDP-43 were absent in 400 controls of white race/ethnicity. The novel identified N352S mutation is predicted to increase TDP-43 phosphorylation, while the G348C mutation might interfere with normal TDP-43 function by forming intermolecular disulfide bridges. CONCLUSIONS Mutations in TARDBP are a rare cause of familial non-SOD1 ALS. The identification of TARDBP mutations provides strong evidence for a direct link between TDP-43 dysfunction and neurodegeneration in ALS.
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Affiliation(s)
- Peter Kühnlein
- Center for Neuropathology and Prion Research, Ludwig-Maximilians University, Munich, Feodor-Lynen-Strasse 23, 81377 Munich, Germany
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676
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Update on recent molecular and genetic advances in frontotemporal lobar degeneration. J Neuropathol Exp Neurol 2008; 67:635-48. [PMID: 18596549 DOI: 10.1097/nen.0b013e31817d751c] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Great strides have been made in the last 2 years in the field of frontotemporal lobar degeneration (FTLD), particularly with respect to the genetics and molecular biology of FTLD with ubiquitinated inclusions. It is now clear that most cases of familial FTLD with ubiquitinated inclusions have mutations in the progranulin gene, located on chromosome 17. It is also clear that most ubiquitinated inclusions in FTLD with ubiquitinated inclusions are composed primarily of TAR DNA-binding protein-43. Thus, FTLDs can be separated into 2 major groups (i.e. tauopathies and ubiquitinopathies), and most of the ubiquitinopathies can now be defined as TAR DNA-binding protein-43 proteinopathies. Many of the familial FTLDs are linked to chromosome 17, including both the familial tauopathies and the familial TAR DNA-binding protein-43 proteinopathies with progranulin mutations. This review highlights the neuropathologic features and the most important discoveries of the last 2 years and places these findings into the historical context of FTLD.
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677
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Rutherford NJ, Zhang YJ, Baker M, Gass JM, Finch NA, Xu YF, Stewart H, Kelley BJ, Kuntz K, Crook RJP, Sreedharan J, Vance C, Sorenson E, Lippa C, Bigio EH, Geschwind DH, Knopman DS, Mitsumoto H, Petersen RC, Cashman NR, Hutton M, Shaw CE, Boylan KB, Boeve B, Graff-Radford NR, Wszolek ZK, Caselli RJ, Dickson DW, Mackenzie IR, Petrucelli L, Rademakers R. Novel mutations in TARDBP (TDP-43) in patients with familial amyotrophic lateral sclerosis. PLoS Genet 2008; 4:e1000193. [PMID: 18802454 PMCID: PMC2527686 DOI: 10.1371/journal.pgen.1000193] [Citation(s) in RCA: 351] [Impact Index Per Article: 21.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2008] [Accepted: 08/07/2008] [Indexed: 12/11/2022] Open
Abstract
The TAR DNA-binding protein 43 (TDP-43) has been identified as the major disease protein in amyotrophic lateral sclerosis (ALS) and frontotemporal lobar degeneration with ubiquitin inclusions (FTLD-U), defining a novel class of neurodegenerative conditions: the TDP-43 proteinopathies. The first pathogenic mutations in the gene encoding TDP-43 (TARDBP) were recently reported in familial and sporadic ALS patients, supporting a direct role for TDP-43 in neurodegeneration. In this study, we report the identification and functional analyses of two novel and one known mutation in TARDBP that we identified as a result of extensive mutation analyses in a cohort of 296 patients with variable neurodegenerative diseases associated with TDP-43 histopathology. Three different heterozygous missense mutations in exon 6 of TARDBP (p.M337V, p.N345K, and p.I383V) were identified in the analysis of 92 familial ALS patients (3.3%), while no mutations were detected in 24 patients with sporadic ALS or 180 patients with other TDP-43-positive neurodegenerative diseases. The presence of p.M337V, p.N345K, and p.I383V was excluded in 825 controls and 652 additional sporadic ALS patients. All three mutations affect highly conserved amino acid residues in the C-terminal part of TDP-43 known to be involved in protein-protein interactions. Biochemical analysis of TDP-43 in ALS patient cell lines revealed a substantial increase in caspase cleaved fragments, including the approximately 25 kDa fragment, compared to control cell lines. Our findings support TARDBP mutations as a cause of ALS. Based on the specific C-terminal location of the mutations and the accumulation of a smaller C-terminal fragment, we speculate that TARDBP mutations may cause a toxic gain of function through novel protein interactions or intracellular accumulation of TDP-43 fragments leading to apoptosis.
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Affiliation(s)
- Nicola J. Rutherford
- Department of Neuroscience, Mayo Clinic, Jacksonville, Florida, United States of America
| | - Yong-Jie Zhang
- Department of Neuroscience, Mayo Clinic, Jacksonville, Florida, United States of America
| | - Matt Baker
- Department of Neuroscience, Mayo Clinic, Jacksonville, Florida, United States of America
| | - Jennifer M. Gass
- Department of Neuroscience, Mayo Clinic, Jacksonville, Florida, United States of America
| | - NiCole A. Finch
- Department of Neuroscience, Mayo Clinic, Jacksonville, Florida, United States of America
| | - Ya-Fei Xu
- Department of Neuroscience, Mayo Clinic, Jacksonville, Florida, United States of America
| | - Heather Stewart
- The ALS Centre, Vancouver General Hospital, Vancouver, British Columbia, Canada
| | - Brendan J. Kelley
- Department of Neurology, Mayo Clinic, Rochester, Minnesota, United States of America
| | - Karen Kuntz
- Department of Neurology, Mayo Clinic, Rochester, Minnesota, United States of America
| | - Richard J. P. Crook
- Department of Neuroscience, Mayo Clinic, Jacksonville, Florida, United States of America
| | - Jemeen Sreedharan
- Department of Clinical Neuroscience, Medical Research Council (MRC) Centre for Neurodegeneration Research, King's College London, London, United Kingdom
- Institute of Psychiatry, King's College London, London, United Kingdom
| | - Caroline Vance
- Department of Clinical Neuroscience, Medical Research Council (MRC) Centre for Neurodegeneration Research, King's College London, London, United Kingdom
- Institute of Psychiatry, King's College London, London, United Kingdom
| | - Eric Sorenson
- Department of Neurology, Mayo Clinic, Rochester, Minnesota, United States of America
| | - Carol Lippa
- Department of Neurology, Drexel University College of Medicine, Philadelphia, Pennsylvania, United States of America
| | - Eileen H. Bigio
- Alzheimer Disease Center, Northwestern University Feinberg School of Medicine, Chicago, Illinois, United States of America
| | - Daniel H. Geschwind
- Neurogenetics Program, Department of Neurology, The David Geffen School of Medicine at University of California, Los Angeles, California, United States of America
| | - David S. Knopman
- Department of Neurology, Mayo Clinic, Rochester, Minnesota, United States of America
| | - Hiroshi Mitsumoto
- Eleanor and Lou Gehrig MDA/ALS Research Center, Columbia University, New York, New York, United States of America
| | - Ronald C. Petersen
- Department of Neurology, Mayo Clinic, Rochester, Minnesota, United States of America
| | - Neil R. Cashman
- Department of Medicine, University of British Columbia, Vancouver, British Columbia, Canada
| | - Mike Hutton
- Department of Neuroscience, Mayo Clinic, Jacksonville, Florida, United States of America
| | - Christopher E. Shaw
- Department of Clinical Neuroscience, Medical Research Council (MRC) Centre for Neurodegeneration Research, King's College London, London, United Kingdom
- Institute of Psychiatry, King's College London, London, United Kingdom
| | - Kevin B. Boylan
- Department of Neurology, Mayo Clinic, Jacksonville Florida, United States of America
| | - Bradley Boeve
- Department of Neurology, Mayo Clinic, Rochester, Minnesota, United States of America
| | | | - Zbigniew K. Wszolek
- Department of Neurology, Mayo Clinic, Jacksonville Florida, United States of America
| | - Richard J. Caselli
- Department of Neurology, Mayo Clinic, Scottsdale, Arizona, United States of America
| | - Dennis W. Dickson
- Department of Neuroscience, Mayo Clinic, Jacksonville, Florida, United States of America
| | - Ian R. Mackenzie
- Department of Pathology, University of British Columbia, Vancouver, British Columbia, Canada
| | - Leonard Petrucelli
- Department of Neuroscience, Mayo Clinic, Jacksonville, Florida, United States of America
| | - Rosa Rademakers
- Department of Neuroscience, Mayo Clinic, Jacksonville, Florida, United States of America
- * E-mail:
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678
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Yamamoto M, Tanaka F, Tatsumi H, Sobue G. A strategy for developing effective amyotropic lateral sclerosis pharmacotherapy: from clinical trials to novel pharmacotherapeutic strategies. Expert Opin Pharmacother 2008; 9:1845-57. [PMID: 18627324 DOI: 10.1517/14656566.9.11.1845] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
BACKGROUND The pathomechanism of sporadic amyotropic lateral sclerosis is not clearly understood, although a proportion of familial amyotropic lateral sclerosis is caused by superoxide dismutase 1 mutations. Theories based on studies of human post-mortem tissue, research on animal models and in vitro work have been proposed for the pathogenesis of amyotropic lateral sclerosis, but the pathogenesis is not the same between sporadic and familial amyotropic lateral sclerosis. OBJECTIVE/METHODS Drug candidates were tested using superoxide dismutase 1 mutant mice. Although the candidates were shown to be effective in mice, clinical trials in humans have failed to identify any truly effective pharmacotherapies in sporadic amyotropic lateral sclerosis, with only riluzole providing a modest improvement in survival. Ongoing or planned trials are exploring the value of antiglutamatergic drugs, antioxidants, neurotrophic factors, anti-inflammatory drugs and anti-aggregation drugs. RESULTS/CONCLUSIONS A combination of drugs acting on different mechanisms is needed for effective therapy. Moreover, gene expression profiling and genome-wide association studies, together with inhibitory RNA techniques, are helpful for developing new pharmacotherapeutic strategies including gene therapy. It is also likely that the recently advanced generation of induced pluripotent stem cells will lead to the development of cell therapy for amyotropic lateral sclerosis. In addition to finding effective therapies, research is also needed in order to detect early disease markers since pharmacotherapy is most beneficial when given early in the course of sporadic amyotropic lateral sclerosis.
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Affiliation(s)
- Masahiko Yamamoto
- Nagoya University Graduate School of Medicine, Department of Neurology, Nagoya 466-8550, Aichi, Japan
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Cook C, Zhang YJ, Xu YF, Dickson DW, Petrucelli L. TDP-43 in neurodegenerative disorders. Expert Opin Biol Ther 2008; 8:969-78. [PMID: 18549326 DOI: 10.1517/14712598.8.7.969] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
BACKGROUND The number of neurodegenerative diseases associated with pathological aggregates of transactivation response element (TAR)-DNA-binding protein 43 (TDP-43) has increased, leading to the new designation 'TDP-43 proteinopathy.' Biochemically, TDP-43 proteinopathies are characterized by decreased solubility, hyperphosphorylation, and cleavage of TDP-43 into 25- and 35-kDa fragments, and by altered cellular localization. OBJECTIVE This review summarizes research characterizing the distribution of TDP-43 pathology in human postmortem brain tissue and discusses possible therapeutic strategies based on genetic and in vitro studies. METHODS We reviewed recent studies of TDP-43 proteinopathy. RESULTS/CONCLUSION Given that several different mutations can lead to TDP-43 proteinopathies, including mutations in progranulin and valosin-containing protein, research is needed to decipher and potentially exploit the link between these mutations and TDP-43 pathology.
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Affiliation(s)
- Casey Cook
- Mayo Clinic, 4500 San Pablo Road Jacksonville, Florida 32224, USA
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680
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van Swieten JC, Heutink P. Mutations in progranulin (GRN) within the spectrum of clinical and pathological phenotypes of frontotemporal dementia. Lancet Neurol 2008; 7:965-74. [PMID: 18771956 DOI: 10.1016/s1474-4422(08)70194-7] [Citation(s) in RCA: 148] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
BACKGROUND Frontotemporal dementia (FTD) is predominantly a presenile disorder that is characterised by behavioural changes and cognitive impairment, particularly in language and executive functions, and is associated with neurodegeneration in the frontal or temporal cortices, or both. Research into FTD has made many advances over the past 20 years that have important implications for clinical practice. Different clinical variants (ie, behavioural, aphasic, and motor neuron disease variants) are now recognised as part of the clinical spectrum of FTD. Neuropathologically, the disease can be divided into two main pathological subtypes: frontotemporal lobar degeneration (FTLD) with neuronal and glial tau inclusions (FTLD-tau); and FTLD with neuronal inclusions that are positive for ubiquitin (FTLD-U). 20-30% of cases of FTD follow an autosomal dominant pattern of inheritance, and half of which are caused by defects in MAPT, CHMP2B, and VCP. RECENT DEVELOPMENTS Mutations in the gene that encodes progranulin (GRN) on chromosome 17q21-22 have been identified in patients with hereditary FTD who have tau-negative, ubiquitin-positive inclusions. The recognition of the clinical phenotype associated with more than 50 different mutations in GRN has expanded the clinical knowledge of FTD to include presentations that resemble Alzheimer's disease, Lewy body disease, and corticobasal syndrome, with a variable age at onset (35-89 years) within families. Another recent breakthrough is the identification of the TAR DNA-binding protein (TARDBP; also known as TDP-43) as the main constituent of FTLD-U with mutations in GRN and with mutations in VCP, as well as in FTLD with amyotrophic lateral sclerosis. WHERE NEXT?: To develop therapeutic strategies to prevent FTD or delay its progression we must understand whether the loss of progranulin leads to the accumulation of TARDBP. In this Rapid Review, we focus on the clinical and pathological phenotypes associated with mutations in GRN, and distinguish those from other forms of hereditary FTD. In addition, we discuss the potential association of mutations in GRN on the pathophysiology of FTD with the accumulation of TARDBP.
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Affiliation(s)
- John C van Swieten
- Department of Neurology, Erasmus Medical Center, Rotterdam, Netherlands.
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681
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Wider C, Dickson DW, Stoessl AJ, Tsuboi Y, Chapon F, Gutmann L, Lechevalier B, Calne DB, Personett DA, Hulihan M, Kachergus J, Rademakers R, Baker MC, Grantier LL, Sujith OK, Brown L, Calne S, Farrer MJ, Wszolek ZK. Pallidonigral TDP-43 pathology in Perry syndrome. Parkinsonism Relat Disord 2008; 15:281-6. [PMID: 18723384 DOI: 10.1016/j.parkreldis.2008.07.005] [Citation(s) in RCA: 78] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/17/2008] [Revised: 07/07/2008] [Accepted: 07/08/2008] [Indexed: 12/12/2022]
Abstract
OBJECTIVE Autosomal dominant parkinsonism, hypoventilation, depression and severe weight loss (Perry syndrome) is an early-onset rapidly progressive disease. At autopsy, previous studies have found severe neuronal loss in the substantia nigra without Lewy bodies. Transactive response DNA-binding protein of 43 kDa (TDP-43) has recently been identified as a major ubiquitinated constituent of neuronal and glial inclusions in frontotemporal lobar degeneration with ubiquitin-positive inclusions and in amyotrophic lateral sclerosis. This study reports clinical, genetic and neuropathologic investigations of Perry syndrome. METHODS Clinical data and autopsy brain tissue samples were collected from eight patients from four genealogically unrelated kindreds with Perry syndrome. Brain tissue was studied with immunohistochemistry and biochemistry for TDP-43. Patients were screened for mutations in the progranulin (GRN) and TDP-43 (TARDBP) genes. RESULTS The mean age at onset was 47 years (range 40-56), and the mean age at death was 52 years (range 44-64). In all patients, we identified TDP-43-positive neuronal inclusions, dystrophic neurites and axonal spheroids in a predominantly pallidonigral distribution, and we demonstrated changes in solubility and electrophoretic mobility of TDP-43 in brain tissue. The inclusions were highly pleomorphic and predominated in the extrapyramidal system, sparing the cortex, hippocampus and motor neurons. There were no mutations in GRN or TARDBP. INTERPRETATION Perry syndrome displays unique TDP-43 pathology that is selective for the extrapyramidal system and spares the neocortex and motor neurons.
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682
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Bigio EH. TAR DNA-binding protein-43 in amyotrophic lateral sclerosis, frontotemporal lobar degeneration, and Alzheimer disease. Acta Neuropathol 2008; 116:135-40. [PMID: 18575875 DOI: 10.1007/s00401-008-0405-z] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2008] [Accepted: 06/12/2008] [Indexed: 12/12/2022]
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683
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Mori F, Tanji K, Zhang HX, Nishihira Y, Tan CF, Takahashi H, Wakabayashi K. Maturation process of TDP-43-positive neuronal cytoplasmic inclusions in amyotrophic lateral sclerosis with and without dementia. Acta Neuropathol 2008; 116:193-203. [PMID: 18560845 DOI: 10.1007/s00401-008-0396-9] [Citation(s) in RCA: 105] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2008] [Revised: 05/29/2008] [Accepted: 05/29/2008] [Indexed: 12/11/2022]
Abstract
To elucidate the maturation process of TDP-43-positive neuronal inclusions, we immunohistochemically and immunoelectron-microscopically examined multiple areas from the brain and spinal cord from ten patients with amyotrophic lateral sclerosis (ALS) and 25 control subjects. TDP-43 immunohistochemistry demonstrated three types of inclusions in ALS: skein-like, round, and dot-like inclusions. Skein-like inclusions were found in all cases of ALS. Dot-like inclusions were found in the anterior horn in seven cases of ALS, all of whom had round inclusions, but not in cases without round inclusions. In addition, careful examination revealed two types of diffuse punctate cytoplasmic staining: linear wisps and punctate granules. Linear wisps were present in all cases of ALS but in none of 25 controls. In contrast, punctate granules were detected in all cases of ALS as well as in five of 13 normal and in seven of 12 diseased controls. Immunoelectron-microscopy revealed that skein-like inclusions consisted of granule-associated parallel filaments. Round and dot-like inclusions were composed of granulo-filamentous structures. However, punctate granules corresponded to the mitochondria and were not immunostained with anti-ubiquitin, indicating that punctate granules represent cross-reaction. We assumed that linear wisps ("fine skein") aggregate as thicker and longer threads ("coarse skein"), whereas round inclusions arise from dot-like inclusions. These findings suggest that there are differences in the formation process between skein-like and round inclusions, despite the antigenic and ultrastructural similarities.
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684
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Nishihira Y, Tan CF, Onodera O, Toyoshima Y, Yamada M, Morita T, Nishizawa M, Kakita A, Takahashi H. Sporadic amyotrophic lateral sclerosis: two pathological patterns shown by analysis of distribution of TDP-43-immunoreactive neuronal and glial cytoplasmic inclusions. Acta Neuropathol 2008; 116:169-82. [PMID: 18481073 DOI: 10.1007/s00401-008-0385-z] [Citation(s) in RCA: 151] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2008] [Revised: 04/26/2008] [Accepted: 04/26/2008] [Indexed: 12/11/2022]
Abstract
A nuclear protein, 43-kDa TAR DNA-binding protein (TDP-43), was recently identified as a component of the ubiquitinated inclusions (UIs) in frontotemporal lobar degeneration (FTLD-U) and sporadic amyotrophic lateral sclerosis (SALS). In the present study using immunohistochemistry, we examined various regions of the nervous system in a series of 35 SALS cases using a polyclonal antibody against TDP-43. Seven of the 35 cases had disease durations of more than 10 years with artificial respiratory support (ARS; duration: 69-156 months). In all cases, TDP-43-immunoreactive (ir) neuronal and glial cytoplasmic inclusions (NCIs and GCIs) were found together in many regions, including the histologically affected lower motor neuron nuclei. Cluster analysis of the distribution pattern of TDP-43-ir NCIs for cases without ARS (n = 28) identified two types (type 1, n = 16; type 2, n = 12). Type 2 was distinguished from type 1 by the presence of TDP-43-ir NCIs in the frontotemporal cortex, hippocampal formation, neostriatum and substantia nigra, and was significantly associated with dementia. Eleven of the 28 cases showed UIs in the hippocampal dentate granule cells, all of which had type-2 distribution pattern. Cases with ARS (n = 7) were also classified into the same types (type 1, n = 5; type 2, n = 2). Cases having type-1 distribution pattern (n = 21) showed no evident neuronal loss in most of the non-motor neuron nuclei where TDP-43-ir NCIs were present, whereas cases having type-2 distribution pattern (n = 14) often showed evident neuronal loss in the frontotemporal cortices, amygdaloid nuclei and substantia nigra. These findings indicate that SALS is a multisystem degenerative disease widely affecting both neurons and glial cells with a heterogeneous pattern of TDP-43-ir NCI distribution (SALS showing type-2 distribution pattern being closely linked to FTLD-U), and that long-term survival supported by a respirator has no apparent influence on the TDP-43 neuronal distribution pattern.
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685
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Foulds P, McAuley E, Gibbons L, Davidson Y, Pickering-Brown SM, Neary D, Snowden JS, Allsop D, Mann DMA. TDP-43 protein in plasma may index TDP-43 brain pathology in Alzheimer's disease and frontotemporal lobar degeneration. Acta Neuropathol 2008; 116:141-6. [PMID: 18506455 PMCID: PMC2464623 DOI: 10.1007/s00401-008-0389-8] [Citation(s) in RCA: 120] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2008] [Revised: 05/08/2008] [Accepted: 05/08/2008] [Indexed: 12/12/2022]
Abstract
Autopsy studies have shown that about 55% of patients with frontotemporal lobar degeneration (FTLD) and 25% of patients with Alzheimer’s disease (AD) harbour TDP-43 immunoreactive pathological changes in their brains. Using ELISA, we investigated whether we could detect the presence, or increased amounts, of TDP-43 in plasma of patients with FTLD and AD compared to normal control subjects. We detected elevated levels of TDP-43 protein in plasma of 46% patients with FTLD with clinical frontotemporal dementia (FTD) and 22% patients with AD, compared to 8% of control subjects. The proportions of patients with FTD and AD showing raised plasma TDP-43 levels correspond closely to those proportions known from autopsy studies to contain TDP-43 pathological changes in their brains. Raised TDP-43 plasma levels may thereby index TDP-43 pathology within the brain. Plasma TDP-43 levels may be a biomarker that can provide a laboratory test capable of identifying the presence of TDP-43 brain pathology in neurodegenerative disease during life. It may help to distinguish those cases of FTLD with ubiquitin/TDP-43 pathology in their brains from those with tauopathy. As a predictive test, plasma TDP-43 level may have great practical value in directing therapeutic strategies aimed at preventing or removing tau or TDP-43 pathological changes from the brain in FTLD and AD.
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686
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Abstract
Amyotrophic lateral sclerosis (ALS) is a progressive motor neuron disease with largely unknown pathogenesis that typically results in death within a few years from diagnosis. There are currently no effective therapies for ALS. Clinical diagnosis usually takes several months to complete and the long delay between symptom onset and diagnosis limits the possibilities for effective intervention and clinical trials. The establishment of protein biomarkers for ALS may aid an earlier diagnosis, facilitating the search for effective therapeutic interventions and monitoring drug efficacy during clinical trials. Biomarkers could also be used to discriminate between subtypes of ALS, to measure disease progression and to detect susceptibility for developing ALS or monitor adverse effects of drug treatment. The present review will discuss the opportunities and proteomic platforms used for biomarker discovery efforts in ALS, summarizing putative ALS protein biomarkers identified in different biofluids.
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Affiliation(s)
- Henrik Ryberg
- Department of Pathology, Center for ALS Research, University of Pittsburgh School of Medicine, Pittsburgh, PA 15261, USA.
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687
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Concomitant TAR-DNA-binding protein 43 pathology is present in Alzheimer disease and corticobasal degeneration but not in other tauopathies. J Neuropathol Exp Neurol 2008; 67:555-64. [PMID: 18520774 DOI: 10.1097/nen.0b013e31817713b5] [Citation(s) in RCA: 301] [Impact Index Per Article: 18.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Pathologic TAR-DNA-binding protein 43 (TDP-43) is a disease protein in frontotemporal lobar degeneration with ubiquitin-positive inclusions (FTLD-U) and amyotrophic lateral sclerosis. We studied the presence, frequency, and distribution of TDP-43 pathology by immunohistochemistry and biochemistry in a series of clinically well-characterized tauopathy patient brains, including 182 Alzheimer disease (AD), 39 corticobasal degeneration, 77 progressive supranuclear palsy, and 12 Pick disease cases and investigated the clinical impact of concomitant TDP-43 pathology in these cases. TAR-DNA-binding protein 43 pathology was found in 25.8% of AD cases. It was restricted to the dentate gyrus and entorhinal cortex in approximately 75% of cases; approximately 25% showed more widespread TDP-43 pathology in frontal and temporal cortices, resembling the FTLD-U subtype associated with progranulin mutations. TAR-DNA-binding protein 43 pathology in AD was associated with significantly longer disease duration, but there was no association with the clinical presentation (148 cases diagnosed as AD and 34 cases diagnosed as frontotemporal lobar degeneration). Progressive supranuclear palsy and Pick disease cases showed no TDP-43 inclusions and no biochemical alterations of TDP-43. There was, however, a unique, predominantly glial TDP-43 pathology with staining of astrocytic plaque-like structures and coiled bodies in 15.4% of corticobasal degeneration cases; this was associated with biochemical TDP-43 changes similar to those in FTLD-U. These findings provide further insight into the burden and clinical significance of TDP-43 pathology in disorders other than FTLD-U and amyotrophic lateral sclerosis.
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688
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Banks GT, Kuta A, Isaacs AM, Fisher EMC. TDP-43 is a culprit in human neurodegeneration, and not just an innocent bystander. Mamm Genome 2008; 19:299-305. [PMID: 18592312 PMCID: PMC2515551 DOI: 10.1007/s00335-008-9117-x] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2008] [Accepted: 05/22/2008] [Indexed: 12/12/2022]
Abstract
In 2006 the protein TDP-43 was identified as the major ubiquitinated component deposited in the inclusion bodies found in two human neurodegenerative diseases, amyotrophic lateral sclerosis and frontotemporal lobar degeneration. The pathogenesis of both disorders is unclear, although they are related by having some overlap of symptoms and now by the shared histopathology of TDP-43 deposition. Now, in 2008, several papers have been published in quick succession describing mutations in the TDP-43 gene, showing they can be a primary cause of amyotrophic lateral sclerosis. There are many precedents in neurodegenerative disease in which rare single-gene mutations have given great insight into understanding disease processes, which is why the TDP-43 mutations are potentially very important.
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Affiliation(s)
- Gareth T Banks
- Department of Neurodegenerative Disease, Institute of Neurology, University College London, Queen Square, London WC1N 3BG, UK
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689
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Luquin N, Yu B, Trent RJ, Morahan JM, Pamphlett R. An analysis of the entire SOD1 gene in sporadic ALS. Neuromuscul Disord 2008; 18:545-52. [DOI: 10.1016/j.nmd.2008.04.013] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2008] [Revised: 03/26/2008] [Accepted: 04/23/2008] [Indexed: 12/31/2022]
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690
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Guerreiro RJ, Schymick JC, Crews C, Singleton A, Hardy J, Traynor BJ. TDP-43 is not a common cause of sporadic amyotrophic lateral sclerosis. PLoS One 2008; 3:e2450. [PMID: 18545701 PMCID: PMC2408729 DOI: 10.1371/journal.pone.0002450] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2008] [Accepted: 05/13/2008] [Indexed: 02/03/2023] Open
Abstract
BACKGROUND TAR DNA binding protein, encoded by TARDBP, was shown to be a central component of ubiquitin-positive, tau-negative inclusions in frontotemporal lobar degeneration (FTLD-U) and amyotrophic lateral sclerosis (ALS). Recently, mutations in TARDBP have been linked to familial and sporadic ALS. METHODOLOGY/PRINCIPAL FINDINGS To further examine the frequency of mutations in TARDBP in sporadic ALS, 279 ALS cases and 806 neurologically normal control individuals of European descent were screened for sequence variants, copy number variants, genetic and haplotype association with disease. An additional 173 African samples from the Human Gene Diversity Panel were sequenced as this population had the highest likelihood of finding changes. No mutations were found in the ALS cases. Several genetic variants were identified in controls, which were considered as non-pathogenic changes. Furthermore, pathogenic structural variants were not observed in the cases and there was no genetic or haplotype association with disease status across the TARDBP locus. CONCLUSIONS Our data indicate that genetic variation in TARDBP is not a common cause of sporadic ALS in North American.
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Affiliation(s)
- Rita J Guerreiro
- Laboratory of Neurogenetics, National Institute of Aging, National Institutes of Health, Bethesda, Maryland, United States of America.
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691
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Igaz LM, Kwong LK, Xu Y, Truax AC, Uryu K, Neumann M, Clark CM, Elman LB, Miller BL, Grossman M, McCluskey LF, Trojanowski JQ, Lee VMY. Enrichment of C-terminal fragments in TAR DNA-binding protein-43 cytoplasmic inclusions in brain but not in spinal cord of frontotemporal lobar degeneration and amyotrophic lateral sclerosis. THE AMERICAN JOURNAL OF PATHOLOGY 2008; 173:182-94. [PMID: 18535185 DOI: 10.2353/ajpath.2008.080003] [Citation(s) in RCA: 248] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
TAR DNA-binding protein (TDP-43) has been recently described as a major pathological protein in both frontotemporal dementia with ubiquitin-positive inclusions (FTLD-U) and amyotrophic lateral sclerosis. However, little is known about the relative abundance and distribution of different pathological TDP-43 species, which include hyperphosphorylated, ubiquitinated, and N-terminally cleaved TDP-43. Here, we developed novel N-terminal (N-t) and C-terminal (C-t)-specific TDP-43 antibodies and performed biochemical and immunohistochemical studies to analyze cortical, hippocampal, and spinal cord tissue from frontotemporal dementia with ubiquitin-positive inclusions and amyotrophic lateral sclerosis cases. C-t-specific TDP-43 antibodies revealed similar abundance, morphology, and distribution of dystrophic neurites and neuronal cytoplasmic inclusions in cortex and hippocampus compared with previously described pan-TDP-43 antibodies. By contrast, N-t-specific TDP-43 antibodies only detected a small subset of these lesions. Biochemical studies confirmed the presence of C-t TDP-43 fragments but not extreme N-t fragments. Surprisingly, immunohistochemical analysis of inclusions in spinal cord motor neurons in both diseases showed that they are N-t and C-t positive. TDP-43 inclusions in Alzheimer's disease brains also were examined, and similar enrichment in C-t TDP-43 fragments was observed in cortex and hippocampus. These results show that the composition of the inclusions in brain versus spinal cord tissues differ, with an increased representation of C-t TDP-43 fragments in cortical and hippocampal regions. Therefore, regionally different pathogenic processes may underlie the development of abnormal TDP-43 proteinopathies.
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Affiliation(s)
- Lionel M Igaz
- Center for Neurodegenerative Disease Research, Department of Pathology and Laboratory Medicine, University of Pennsylvania School of Medicine, 3600 Spruce St., 3rd floor, Maloney Bldg., Philadelphia, PA 19104, USA.
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692
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Yokoseki A, Shiga A, Tan CF, Tagawa A, Kaneko H, Koyama A, Eguchi H, Tsujino A, Ikeuchi T, Kakita A, Okamoto K, Nishizawa M, Takahashi H, Onodera O. TDP-43 mutation in familial amyotrophic lateral sclerosis. Ann Neurol 2008; 63:538-42. [PMID: 18438952 DOI: 10.1002/ana.21392] [Citation(s) in RCA: 290] [Impact Index Per Article: 18.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disorder. Accumulating evidence has shown that 43kDa TAR-DNA-binding protein (TDP-43) is the disease protein in ALS and frontotemporal lobar degeneration. We previously reported a familial ALS with Bumina bodies and TDP-43-positive skein-like inclusions in the lower motor neurons; these findings are indistinguishable from those of sporadic ALS. In three affected individuals in two generations of one family, we found a single base-pair change from A to G at position 1028 in TDP-43, which resulted in a Gln-to-Arg substitution at position 343. Our findings provide a new insight into the molecular pathogenesis of ALS.
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Affiliation(s)
- Akio Yokoseki
- Department of Neurology, Brain Research Institute, Niigata University, Niigata, Japan
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693
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Fujita Y, Mizuno Y, Takatama M, Okamoto K. Anterior horn cells with abnormal TDP-43 immunoreactivities show fragmentation of the Golgi apparatus in ALS. J Neurol Sci 2008; 269:30-4. [DOI: 10.1016/j.jns.2007.12.016] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2007] [Accepted: 12/11/2007] [Indexed: 10/22/2022]
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694
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Magnetic Source Imaging of Cortical Dysfunction in Amyotrophic Lateral Sclerosis. Am J Phys Med Rehabil 2008; 87:427-37. [DOI: 10.1097/phm.0b013e318174e7f1] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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695
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Van Deerlin VM, Leverenz JB, Bekris LM, Bird TD, Yuan W, Elman LB, Clay D, Wood EM, Chen-Plotkin AS, Martinez-Lage M, Steinbart E, McCluskey L, Grossman M, Neumann M, Wu IL, Yang WS, Kalb R, Galasko DR, Montine TJ, Trojanowski JQ, Lee VMY, Schellenberg GD, Yu CE. TARDBP mutations in amyotrophic lateral sclerosis with TDP-43 neuropathology: a genetic and histopathological analysis. Lancet Neurol 2008; 7:409-16. [PMID: 18396105 DOI: 10.1016/s1474-4422(08)70071-1] [Citation(s) in RCA: 537] [Impact Index Per Article: 33.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
BACKGROUND TDP-43 is a major component of the ubiquitinated inclusions that characterise amyotrophic lateral sclerosis (ALS) and frontotemporal lobar degeneration (FTLD) with ubiquitin inclusions (FTLD-U). TDP-43 is an RNA-binding and DNA-binding protein that has many functions and is encoded by the TAR DNA-binding protein gene (TARDBP) on chromosome 1. Our aim was to investigate whether TARDBP is a candidate disease gene for familial ALS that is not associated with mutations in superoxide dismutase 1 (SOD1). METHODS TARDBP was sequenced in 259 patients with ALS, FTLD, or both. We used TaqMan-based SNP genotyping to screen for the identified variants in control groups matched to two kindreds of patients for age and ethnic origin. Additional clinical, genetic, and pathological assessments were made in these two families. FINDINGS We identified two variants in TARDBP, which would encode Gly290Ala and Gly298Ser forms of TDP-43, in two kindreds with familial ALS. The variants seem to be pathogenic because they co-segregated with disease in both families, were absent in controls, and were associated with TDP-43 neuropathology in both members of one of these families for whom CNS tissue was available. INTERPRETATION The Gly290Ala and Gly298Ser mutations are located in the glycine-rich domain of TDP-43, which regulates gene expression and mediates protein-protein interactions such as those with heterogeneous ribonucleoproteins. Owing to the varied and important cellular functions of TDP-43, these mutations might cause neurodegeneration through both gains and losses of function. The finding of pathogenic mutations in TARDBP implicates TDP-43 as an active mediator of neurodegeneration in TDP-43 proteinopathies, a class of disorder that includes ALS and FTLD-U. FUNDING National Institutes of Health (AG10124, AG17586, AG005136-22, PO1 AG14382), Department of Veterans Affairs, Friedrich-Baur Stiftung (0017/2007), US Public Health Service, ALS Association, and Fundació 'la Caixa'.
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Affiliation(s)
- Vivianna M Van Deerlin
- Center for Neurodegenerative Disease Research, Department of Pathology and Laboratory Medicine, University of Pennsylvania School of Medicine, Philadelphia, PA, USA
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696
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TARDBP mutations in individuals with sporadic and familial amyotrophic lateral sclerosis. Nat Genet 2008; 40:572-4. [PMID: 18372902 DOI: 10.1038/ng.132] [Citation(s) in RCA: 1153] [Impact Index Per Article: 72.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2007] [Accepted: 03/05/2008] [Indexed: 12/11/2022]
Abstract
Recently, TDP-43 was identified as a key component of ubiquitinated aggregates in amyotrophic lateral sclerosis (ALS), an adult-onset neurological disorder that leads to the degeneration of motor neurons. Here we report eight missense mutations in nine individuals--six from individuals with sporadic ALS (SALS) and three from those with familial ALS (FALS)--and a concurring increase of a smaller TDP-43 product. These findings further corroborate that TDP-43 is involved in ALS pathogenesis.
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697
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Mackenzie IRA, Foti D, Woulfe J, Hurwitz TA. Atypical frontotemporal lobar degeneration with ubiquitin-positive, TDP-43-negative neuronal inclusions. ACTA ACUST UNITED AC 2008; 131:1282-93. [PMID: 18362096 DOI: 10.1093/brain/awn061] [Citation(s) in RCA: 116] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Frontotemporal lobar degeneration with ubiquitinated inclusions (FTLD-U) is the most common neuropathology associated with the clinical syndrome of frontotemporal dementia (FTD). Recently, TDP-43 was identified as the ubiquitinated pathological protein in both FTLD-U and sporadic amyotrophic lateral sclerosis. Although a number of studies have now confirmed that most sporadic and familial cases of FTLD-U are TDP-43 proteinopathies, there are exceptions. We describe six cases of early onset FTD with FTLD-U pathology that was negative for TDP-43, which we refer to as 'atypical' FTLD-U. All cases were sporadic and had very early onset FTD (mean age = 35 years), characterized by severe progressive psychobehavioural abnormalities in the absence of significant aphasia, cognitive-intellectual dysfunction or motor features. The neuropathological features were highly consistent, with small, round, neuronal cytoplasmic inclusions that were immunoreactive for ubiquitin (ub-ir), but negative for tau, alpha-synuclein, intermediate filaments and TDP-43. Cytoplasmic inclusions were most numerous in the neocortex, dentate granule cells and hippocampal pyramidal neurons. Ub-ir neuronal intra-nuclear inclusions were also present in neocortical and hippocampal neurons and had the unusual appearance of straight, curved or twisted filaments. We believe that these cases represent a new entity that is clinically and pathologically distinct from all currently recognized subtypes of FTLD. Moreover, the existence of such cases indicates that the designations of 'FTLD-U' and 'TDP-43 proteinopathy' should not be considered to be synonymous.
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Affiliation(s)
- Ian R A Mackenzie
- Department of Pathology, University of British Columbia, Vancouver General Hospital, 855 West 12th Avenue, Vancouver, British Columbia, V5Z 1M9 Canada.
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698
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Abstract
Pick disease (PiD) is a frontotemporal dementia characterized by frontal and temporal atrophy, neuronal loss, gliosis, ballooned neurons that are positive for alpha-B crystallin and neurofilament, and the presence of tau- and ubiquitin-positive Pick bodies. TAR-DNA binding protein 43 (TDP-43) has been found to be a component of ubiquitinated inclusions in other neurodegenerative diseases, including frontotemporal lobar degeneration with ubiquitinated inclusions and amyotrophic lateral sclerosis. Fifteen cases of PiD were examined using immunohistochemical methods, and 5 cases with both Pick bodies and smaller intracytoplasmic inclusions that showed staining for ubiquitin, tau, and TDP-43 were observed. The presence of TDP-43 inclusions in PiD suggests that TDP-43 accumulation may be an important component of many neurodegenerative diseases, and that its presence in only some cases of PiD may indicate different pathways of disease development.
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699
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Zhang HX, Tanji K, Mori F, Wakabayashi K. Epitope mapping of 2E2-D3, a monoclonal antibody directed against human TDP-43. Neurosci Lett 2008; 434:170-4. [DOI: 10.1016/j.neulet.2008.01.060] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2007] [Revised: 01/08/2008] [Accepted: 01/19/2008] [Indexed: 11/25/2022]
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700
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Nakamura M, Ito H, Wate R, Nakano S, Hirano A, Kusaka H. Phosphorylated Smad2/3 immunoreactivity in sporadic and familial amyotrophic lateral sclerosis and its mouse model. Acta Neuropathol 2008; 115:327-34. [PMID: 18210139 DOI: 10.1007/s00401-007-0337-z] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2007] [Revised: 12/21/2007] [Accepted: 12/21/2007] [Indexed: 01/15/2023]
Abstract
Phosphorylated Smad2/3 (pSmad2/3), the central mediators of transforming growth factor (TGF)-beta signaling, were recently identified in tau-positive inclusions in certain neurodegenerative disorders. To clarify whether the localization of pSmad2/3 is altered in amyotrophic lateral sclerosis (ALS), we immunohistochemically examined spinal cords from sporadic ALS (SALS), from familial ALS (FALS) patients with the A4V mutation in their Cu/Zn superoxide dismutase (SOD1) gene, and from G93A mutant SOD1 transgenic (mSOD1 Tg) mice. In control spinal cords, pSmad2/3 immunoreactivity was observed exclusively in neuronal and glial nuclei. In SALS and FALS patients the nuclei showed increased immunoreactivity for pSmad2/3. Noticeably, round hyaline inclusions (RHIs) and skein-like inclusions of SALS patients were immunoreactive for pSmad2/3. Double immunofluorescence staining for pSmad2/3 and transactive response-DNA-binding protein (TDP)-43 revealed co-localization of these proteins within RHIs. In contrast, Bunina bodies in SALS and Lewy body-like hyaline inclusions (LBHIs) in FALS were devoid of labeling for pSmad2/3. Similarly, in the mSOD1 Tg mice pSmad2/3 immunoreactivity was increased in the nuclei, while LBHIs were not labeled. These findings suggest increased TGF-beta-Smad signaling in SALS, FALS, and mSOD1 Tg mice, as well as impaired TGF-beta signal transduction in RHI-bearing neurons of SALS patients, presumably at the step of pSmad2/3 translocation into the nucleus. The pathomechanisms, including the process of inclusion development, appears to be different between SALS and mSOD1-related FALS or Tg mice.
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Affiliation(s)
- Masataka Nakamura
- Department of Neurology, Kansai Medical University, 10-15, Fumizono-cho, Moriguchi, Osaka 570-8507, Japan
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