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Clark LN, Gao Y, Wang GT, Hernandez N, Ashley-Koch A, Jankovic J, Ottman R, Leal SM, Rodriguez SMB, Louis ED. Whole genome sequencing identifies candidate genes for familial essential tremor and reveals biological pathways implicated in essential tremor aetiology. EBioMedicine 2022; 85:104290. [PMID: 36183486 PMCID: PMC9525816 DOI: 10.1016/j.ebiom.2022.104290] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2021] [Revised: 08/25/2022] [Accepted: 09/13/2022] [Indexed: 12/13/2022] Open
Abstract
Background Essential tremor (ET), one of the most common neurological disorders, has a phenotypically heterogeneous presentation characterized by bilateral kinetic tremor of the arms and, in some patients, tremor involving other body regions (e.g., head, voice). Genetic studies suggest that ET is genetically heterogeneous. Methods We analyzed whole genome sequence data (WGS) generated on 104 multi-generational white families with European ancestry affected by ET. Genome-wide parametric linkage and association scans were analyzed using adjusted logistic regression models through the application of the Pseudomarker software. To investigate the additional contribution of rare variants in familial ET, we also performed an aggregate variant non-parametric linkage (NPL) analysis using the collapsed haplotype method implemented in CHP-NPL software. Findings Parametric linkage analysis of common variants identified several loci with significant evidence of linkage (HLOD ≥3.6). Among the gene regions within the strongest ET linkage peaks were BTC (4q13.3, HLOD=4.53), N6AMT1 (21q21.3, HLOD=4.31), PCDH9 (13q21.32, HLOD=4.21), EYA1 (8q13.3, HLOD=4.04), RBFOX1 (16p13.3, HLOD=4.02), MAPT (17q21.31, HLOD=3.99) and SCARB2 (4q21.1, HLOD=3.65). CHP-NPL analysis identified fifteen additional genes with evidence of significant linkage (LOD ≥3.8). These genes include TUBB2A, VPS33B, STEAP1B, SPINK5, ZRANB1, TBC1D3C, PDPR, NPY4R, ETS2, ZNF736, SPATA21, ARL17A, PZP, BLK and CCDC94. In one ET family contributing to the linkage peak on chromosome 16p13.3, we identified a likely pathogenic heterozygous canonical splice acceptor variant in exon 2 of RBFOX1 (ENST00000547372; c.4-2A>G), that co-segregated with the ET phenotype in the family. Interpretation Linkage and association analyses of WGS identified several novel ET candidate genes, which are implicated in four major pathways that include 1) the epidermal growth factor receptor-phosphatidylinositol-4,5-bisphosphate 3-kinase catalytic subunit alpha-AKT serine/threonine kinase 1 (EGFR-PI3K-AKT) and Mitogen-activated protein Kinase 1 (ERK) pathways, 2) Reactive oxygen species (ROS) and DNA repair, 3) gamma-aminobutyric acid-ergic (GABAergic) system and 4) RNA binding and regulation of RNA processes. Our study provides evidence for a possible overlap in the genetic architecture of ET, neurological disease, cancer and aging. The genes and pathways identified can be prioritized in future genetic and functional studies. Funding National Institutes of Health, NINDS, NS073872 (USA) and NIA AG058131(USA).
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Affiliation(s)
- Lorraine N Clark
- Department of Pathology and Cell Biology, Vagelos College of Physicians and Surgeons, Columbia University Irving Medical Center, New York, NY, USA; The Taub Institute for Research on Alzheimer's Disease and The Aging Brain, Columbia University Irving Medical Center, New York, NY, USA.
| | - Yizhe Gao
- The G.H. Sergievsky Center, Vagelos College of Physicians and Surgeons, Columbia University Irving Medical Center, New York, NY, USA; Department of Neurology, Vagelos College of Physicians and Surgeons, Columbia University Irving Medical Center, New York, NY, USA; The Center for Statistical Genetics, Columbia University Irving Medical Center, New York, NY, USA
| | - Gao T Wang
- The G.H. Sergievsky Center, Vagelos College of Physicians and Surgeons, Columbia University Irving Medical Center, New York, NY, USA; Department of Neurology, Vagelos College of Physicians and Surgeons, Columbia University Irving Medical Center, New York, NY, USA; The Center for Statistical Genetics, Columbia University Irving Medical Center, New York, NY, USA
| | - Nora Hernandez
- Department of Neurology, University of Texas Southwestern Medical Center, Dallas TX, USA
| | - Allison Ashley-Koch
- Duke Molecular Physiology Institute, Duke University Medical Center, Durham, NC, USA
| | - Joseph Jankovic
- Parkinson's Disease Center and Movement Disorders Clinic, Department of Neurology, Baylor College of Medicine, Houston TX, USA
| | - Ruth Ottman
- The G.H. Sergievsky Center, Vagelos College of Physicians and Surgeons, Columbia University Irving Medical Center, New York, NY, USA; Department of Neurology, Vagelos College of Physicians and Surgeons, Columbia University Irving Medical Center, New York, NY, USA; Department of Epidemiology, Mailman School of Public Health, Columbia University Irving Medical Center, New York, NY, USA; Division of Translational Epidemiology, New York State Psychiatric Institute, New York, NY, USA
| | - Suzanne M Leal
- The Taub Institute for Research on Alzheimer's Disease and The Aging Brain, Columbia University Irving Medical Center, New York, NY, USA; The G.H. Sergievsky Center, Vagelos College of Physicians and Surgeons, Columbia University Irving Medical Center, New York, NY, USA; Department of Neurology, Vagelos College of Physicians and Surgeons, Columbia University Irving Medical Center, New York, NY, USA; The Center for Statistical Genetics, Columbia University Irving Medical Center, New York, NY, USA
| | - Sandra M Barral Rodriguez
- The Taub Institute for Research on Alzheimer's Disease and The Aging Brain, Columbia University Irving Medical Center, New York, NY, USA; The G.H. Sergievsky Center, Vagelos College of Physicians and Surgeons, Columbia University Irving Medical Center, New York, NY, USA; Department of Neurology, Vagelos College of Physicians and Surgeons, Columbia University Irving Medical Center, New York, NY, USA.
| | - Elan D Louis
- Department of Neurology, University of Texas Southwestern Medical Center, Dallas TX, USA.
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2
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Cimini S, Giaccone G, Tagliavini F, Costantino M, Perego P, Rossi G. P301L tau mutation leads to alterations of cell cycle, DNA damage response and apoptosis: evidence for a role of tau in cancer. Biochem Pharmacol 2022; 200:115043. [DOI: 10.1016/j.bcp.2022.115043] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2022] [Accepted: 04/11/2022] [Indexed: 01/14/2023]
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3
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Gil L, Niño SA, Guerrero C, Jiménez-Capdeville ME. Phospho-Tau and Chromatin Landscapes in Early and Late Alzheimer's Disease. Int J Mol Sci 2021; 22:ijms221910283. [PMID: 34638632 PMCID: PMC8509045 DOI: 10.3390/ijms221910283] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2021] [Revised: 09/17/2021] [Accepted: 09/18/2021] [Indexed: 12/25/2022] Open
Abstract
Cellular identity is determined through complex patterns of gene expression. Chromatin, the dynamic structure containing genetic information, is regulated through epigenetic modulators, mainly by the histone code. One of the main challenges for the cell is maintaining functionality and identity, despite the accumulation of DNA damage throughout the aging process. Replicative cells can remain in a senescent state or develop a malign cancer phenotype. In contrast, post-mitotic cells such as pyramidal neurons maintain extraordinary functionality despite advanced age, but they lose their identity. This review focuses on tau, a protein that protects DNA, organizes chromatin, and plays a crucial role in genomic stability. In contrast, tau cytosolic aggregates are considered hallmarks of Alzheimer´s disease (AD) and other neurodegenerative disorders called tauopathies. Here, we explain AD as a phenomenon of chromatin dysregulation directly involving the epigenetic histone code and a progressive destabilization of the tau–chromatin interaction, leading to the consequent dysregulation of gene expression. Although this destabilization could be lethal for post-mitotic neurons, tau protein mediates profound cellular transformations that allow for their temporal survival.
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Affiliation(s)
- Laura Gil
- Departamento de Genética, Escuela de Medicina, Universidad “Alfonso X el Sabio”, 28691 Madrid, Spain;
| | - Sandra A. Niño
- Departamento de Bioquímica, Facultad de Medicina, Universidad Autónoma, de San Luis Potosí 78210, Mexico;
| | - Carmen Guerrero
- Banco de Cerebros (Biobanco), Hospital Universitario Fundación Alcorcón, Alcorcón, 28922 Madrid, Spain;
| | - María E. Jiménez-Capdeville
- Departamento de Bioquímica, Facultad de Medicina, Universidad Autónoma, de San Luis Potosí 78210, Mexico;
- Correspondence: ; Tel.: +52-444-826-2366
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4
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Siano G, Falcicchia C, Origlia N, Cattaneo A, Di Primio C. Non-Canonical Roles of Tau and Their Contribution to Synaptic Dysfunction. Int J Mol Sci 2021; 22:ijms221810145. [PMID: 34576308 PMCID: PMC8466023 DOI: 10.3390/ijms221810145] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2021] [Revised: 09/12/2021] [Accepted: 09/17/2021] [Indexed: 12/13/2022] Open
Abstract
Tau plays a central role in a group of neurodegenerative disorders collectively named tauopathies. Despite the wide range of diverse symptoms at the onset and during the progression of the pathology, all tauopathies share two common hallmarks, namely the misfolding and aggregation of Tau protein and progressive synaptic dysfunctions. Tau aggregation correlates with cognitive decline and behavioural impairment. The mechanistic link between Tau misfolding and the synaptic dysfunction is still unknown, but this correlation is well established in the human brain and also in tauopathy mouse models. At the onset of the pathology, Tau undergoes post-translational modifications (PTMs) inducing the detachment from the cytoskeleton and its release in the cytoplasm as a soluble monomer. In this condition, the physiological enrichment in the axon is definitely disrupted, resulting in Tau relocalization in the cell soma and in dendrites. Subsequently, Tau aggregates into toxic oligomers and amyloidogenic forms that disrupt synaptic homeostasis and function, resulting in neuronal degeneration. The involvement of Tau in synaptic transmission alteration in tauopathies has been extensively reviewed. Here, we will focus on non-canonical Tau functions mediating synapse dysfunction.
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Affiliation(s)
- Giacomo Siano
- Laboratory of Biology, BIO@SNS, Scuola Normale Superiore, Piazza dei Cavalieri 7, 56126 Pisa, Italy;
| | - Chiara Falcicchia
- Institute of Neuroscience, Italian National Research Council, Via Moruzzi 1, 56124 Pisa, Italy; (C.F.); (N.O.)
| | - Nicola Origlia
- Institute of Neuroscience, Italian National Research Council, Via Moruzzi 1, 56124 Pisa, Italy; (C.F.); (N.O.)
| | - Antonino Cattaneo
- Laboratory of Biology, BIO@SNS, Scuola Normale Superiore, Piazza dei Cavalieri 7, 56126 Pisa, Italy;
- European Brain Research Institute (EBRI), Fondazione Rita Levi-Montalcini, Viale Regina Elena 295, 00161 Roma, Italy
- Correspondence: (A.C.); (C.D.P.)
| | - Cristina Di Primio
- Institute of Neuroscience, Italian National Research Council, Via Moruzzi 1, 56124 Pisa, Italy; (C.F.); (N.O.)
- Correspondence: (A.C.); (C.D.P.)
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5
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Tau and Alpha Synuclein Synergistic Effect in Neurodegenerative Diseases: When the Periphery Is the Core. Int J Mol Sci 2020; 21:ijms21145030. [PMID: 32708732 PMCID: PMC7404325 DOI: 10.3390/ijms21145030] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2020] [Revised: 07/13/2020] [Accepted: 07/14/2020] [Indexed: 02/08/2023] Open
Abstract
In neuronal cells, tau is a microtubule-associated protein placed in axons and alpha synuclein is enriched at presynaptic terminals. They display a propensity to form pathologic aggregates, which are considered the underlying cause of Alzheimer's and Parkinson's diseases. Their functional impairment induces loss of axonal transport, synaptic and mitochondrial disarray, leading to a "dying back" pattern of degeneration, which starts at the periphery of cells. In addition, pathologic spreading of alpha-synuclein from the peripheral nervous system to the brain through anatomical connectivity has been demonstrated for Parkinson's disease. Thus, examination of the extent and types of tau and alpha-synuclein in peripheral tissues and their relation to brain neurodegenerative diseases is of relevance since it may provide insights into patterns of protein aggregation and neurodegeneration. Moreover, peripheral nervous tissues are easily accessible in-vivo and can play a relevant role in the early diagnosis of these conditions. Up-to-date investigations of tau species in peripheral tissues are scant and have mainly been restricted to rodents, whereas, more evidence is available on alpha synuclein in peripheral tissues. Here we aim to review the literature on the functional role of tau and alpha synuclein in physiological conditions and disease at the axonal level, their distribution in peripheral tissues, and discuss possible commonalities/diversities as well as their interaction in proteinopathies.
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6
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Potter H, Chial HJ, Caneus J, Elos M, Elder N, Borysov S, Granic A. Chromosome Instability and Mosaic Aneuploidy in Neurodegenerative and Neurodevelopmental Disorders. Front Genet 2019; 10:1092. [PMID: 31788001 PMCID: PMC6855267 DOI: 10.3389/fgene.2019.01092] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2019] [Accepted: 10/09/2019] [Indexed: 12/15/2022] Open
Abstract
Evidence from multiple laboratories has accumulated to show that mosaic neuronal aneuploidy and consequent apoptosis characterizes and may underlie neuronal loss in many neurodegenerative diseases, particularly Alzheimer’s disease and frontotemporal dementia. Furthermore, several neurodevelopmental disorders, including Seckel syndrome, ataxia telangiectasia, Nijmegen breakage syndrome, Niemann–Pick type C, and Down syndrome, have been shown to also exhibit mosaic aneuploidy in neurons in the brain and in other cells throughout the body. Together, these results indicate that both neurodegenerative and neurodevelopmental disorders with apparently different pathogenic causes share a cell cycle defect that leads to mosaic aneuploidy in many cell types. When such mosaic aneuploidy arises in neurons in the brain, it promotes apoptosis and may at least partly underlie the cognitive deficits that characterize the neurological symptoms of these disorders. These findings have implications for both diagnosis and treatment/prevention.
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Affiliation(s)
- Huntington Potter
- Department of Neurology, Rocky Mountain Alzheimer's Disease Center, University of Colorado, Aurora, CO, United States.,Linda Crnic Institute for Down Syndrome, University of Colorado, Aurora, CO, United States
| | - Heidi J Chial
- Department of Neurology, Rocky Mountain Alzheimer's Disease Center, University of Colorado, Aurora, CO, United States.,Linda Crnic Institute for Down Syndrome, University of Colorado, Aurora, CO, United States
| | - Julbert Caneus
- NanoScience Technology Center, University of Central Florida, Orlando, FL, United States
| | - Mihret Elos
- Department of Neurology, Rocky Mountain Alzheimer's Disease Center, University of Colorado, Aurora, CO, United States.,Linda Crnic Institute for Down Syndrome, University of Colorado, Aurora, CO, United States
| | - Nina Elder
- Department of Neurology, Rocky Mountain Alzheimer's Disease Center, University of Colorado, Aurora, CO, United States.,Linda Crnic Institute for Down Syndrome, University of Colorado, Aurora, CO, United States
| | - Sergiy Borysov
- Department of Math and Science, Saint Leo University, Saint Leo, FL, United States
| | - Antoneta Granic
- AGE Research Group, Institute of Neuroscience, Newcastle University, Newcastle upon Tyne, United Kingdom.,Newcastle University Institute for Ageing, NIHR Newcastle Biomedical Research Centre, Newcastle upon Tyne, United Kingdom.,Newcastle upon Tyne Hospitals, NHS Foundation Trust, Newcastle upon Tyne, United Kingdom
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7
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Siano G, Varisco M, Caiazza MC, Quercioli V, Mainardi M, Ippolito C, Cattaneo A, Di Primio C. Tau Modulates VGluT1 Expression. J Mol Biol 2019; 431:873-884. [PMID: 30664870 DOI: 10.1016/j.jmb.2019.01.023] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2019] [Accepted: 01/09/2019] [Indexed: 02/07/2023]
Abstract
Tau displacement from microtubules is the first step in the onset of tauopathies and is followed by toxic protein aggregation. However, other non-canonical functions of Tau might have a role in these pathologies. Here, we demonstrate that a small amount of Tau localizes in the nuclear compartment and accumulates in both the soluble and chromatin-bound fractions. We show that favoring Tau nuclear translocation and accumulation, by Tau overexpression or detachment from MTs, increases the expression of VGluT1, a disease-relevant gene directly involved in glutamatergic synaptic transmission. Remarkably, the P301L mutation, related to frontotemporal dementia FTDP-17, impairs this mechanism leading to a loss of function. Altogether, our results provide the demonstration of a direct physiological role of Tau on gene expression. Alterations of this mechanism may be at the basis of the onset of neurodegeneration.
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Affiliation(s)
- Giacomo Siano
- Laboratory of Biology, BIO@SNS, Scuola Normale Superiore, Pisa, Italy
| | - Martina Varisco
- Laboratory of Biology, BIO@SNS, Scuola Normale Superiore, Pisa, Italy
| | | | | | - Marco Mainardi
- Laboratory of Biology, BIO@SNS, Scuola Normale Superiore, Pisa, Italy
| | - Chiara Ippolito
- Unit of Histology, Department of Clinical and Experimental Medicine, University of Pisa, Pisa, Italy
| | - Antonino Cattaneo
- Laboratory of Biology, BIO@SNS, Scuola Normale Superiore, Pisa, Italy
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8
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Galas MC, Bonnefoy E, Buee L, Lefebvre B. Emerging Connections Between Tau and Nucleic Acids. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2019; 1184:135-143. [PMID: 32096035 DOI: 10.1007/978-981-32-9358-8_12] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Connections between tau and nucleic acids have been largely underestimated until recently when several reports highlighted new key roles of tau in relation with DNA and RNA structure, metabolism and integrity, and their implications in the context of tauopathies. Here we focus on recent advances involving tau and nucleic acids in neuronal and non-neuronal cells. Implication of tau and tau pathology in mechanisms regulating genome integrity, chromatin organization and RNA metabolism, highlight the connections between tau and nucleic acid as major mechanisms in neuronal homeostasis and the etiopathology of tauopathies.
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Affiliation(s)
- Marie-Christine Galas
- University of Lille, INSERM, CHU-Lille, UMR-S 1172, Alzheimer & Tauopathies, LabEx DISTALZ, Lille, France.
| | | | - Luc Buee
- University of Lille, INSERM, CHU-Lille, UMR-S 1172, Alzheimer & Tauopathies, LabEx DISTALZ, Lille, France
| | - Bruno Lefebvre
- University of Lille, INSERM, CHU-Lille, UMR-S 1172, Alzheimer & Tauopathies, LabEx DISTALZ, Lille, France
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9
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Castellani RJ, Perry G. Tau Biology, Tauopathy, Traumatic Brain Injury, and Diagnostic Challenges. J Alzheimers Dis 2019; 67:447-467. [PMID: 30584140 PMCID: PMC6398540 DOI: 10.3233/jad-180721] [Citation(s) in RCA: 61] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/08/2018] [Indexed: 12/12/2022]
Abstract
There is considerable interest in the pathobiology of tau protein, given its potential role in neurodegenerative diseases and aging. Tau is an important microtubule associated protein, required for the assembly of tubulin into microtubules and maintaining structural integrity of axons. Tau has other diverse cellular functions involving signal transduction, cellular proliferation, developmental neurobiology, neuroplasticity, and synaptic activity. Alternative splicing results in tau isoforms with differing microtubule binding affinity, differing representation in pathological inclusions in certain disease states, and differing roles in developmental biology and homeostasis. Tau haplotypes confer differing susceptibility to neurodegeneration. Tau phosphorylation is a normal metabolic process, critical in controlling tau's binding to microtubules, and is ongoing within the brain at all times. Tau may be hyperphosphorylated, and may aggregate as detectable fibrillar deposits in tissues, in both aging and neurodegenerative disease. The hypothesis that p-tau is neurotoxic has prompted constructs related to isomers, low-n assembly intermediates or oligomers, and the "tau prion". Human postmortem studies have elucidated broad patterns of tauopathy, with tendencies for those patterns to differ as a function of disease phenotype. However, there is extensive overlap, not only between genuine neurodegenerative diseases, but also between aging and disease. Recent studies highlight uniqueness to pathological patterns, including a pattern attributed to repetitive head trauma, although clinical correlations have been elusive. The diagnostic process for tauopathies and neurodegenerative diseases in general is challenging in many respects, and may be particularly problematic for postmortem evaluation of former athletes and military service members.
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Affiliation(s)
- Rudy J. Castellani
- Departments of Pathology and Neuroscience, West Virginia University School of Medicine, Morgantown, WV, USA
| | - George Perry
- College of Sciences, University of Texas, San Antonio, San Antonio, TX, USA
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10
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Rossi G, Redaelli V, Contiero P, Fabiano S, Tagliabue G, Perego P, Benussi L, Bruni AC, Filippini G, Farinotti M, Giaccone G, Buiatiotis S, Manzoni C, Ferrari R, Tagliavini F. Tau Mutations Serve as a Novel Risk Factor for Cancer. Cancer Res 2018; 78:3731-3739. [PMID: 29794074 DOI: 10.1158/0008-5472.can-17-3175] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2017] [Revised: 02/23/2018] [Accepted: 05/04/2018] [Indexed: 11/16/2022]
Abstract
In addition to its well-recognized role in neurodegeneration, tau participates in maintenance of genome stability and chromosome integrity. In particular, peripheral cells from patients affected by frontotemporal lobar degeneration carrying a mutation in tau gene (genetic tauopathies), as well as cells from animal models, show chromosome numerical and structural aberrations, chromatin anomalies, and a propensity toward abnormal recombination. As genome instability is tightly linked to cancer development, we hypothesized that mutated tau may be a susceptibility factor for cancer. Here we conducted a retrospective cohort study comparing cancer incidence in families affected by genetic tauopathies to control families. In addition, we carried out a bioinformatics analysis to highlight pathways associated with the tau protein interactome. We report that the risk of developing cancer is significantly higher in families affected by genetic tauopathies, and a high proportion of tau protein interactors are involved in cellular processes particularly relevant to cancer. These findings disclose a novel role of tau as a risk factor for cancer, providing new insights in the various pathologic roles of mutated tau.Significance: This study reveals a novel role for tau as a risk factor for cancer, providing new insights beyond its role in neurodegeneration. Cancer Res; 78(13); 3731-9. ©2018 AACR.
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Affiliation(s)
- Giacomina Rossi
- Unit of Neurology V and Neuropathology, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milano, Italy.
| | - Veronica Redaelli
- Unit of Neurology V and Neuropathology, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milano, Italy
| | - Paolo Contiero
- Environmental Epidemiology Unit, Fondazione IRCCS Istituto Nazionale dei Tumori, Milano, Italy
| | - Sabrina Fabiano
- Cancer Registry Unit, Fondazione IRCCS Istituto Nazionale dei Tumori, Milano, Italy
| | - Giovanna Tagliabue
- Cancer Registry Unit, Fondazione IRCCS Istituto Nazionale dei Tumori, Milano, Italy
| | - Paola Perego
- Molecular Pharmacology Unit, Fondazione IRCCS Istituto Nazionale dei Tumori, Milano, Italy
| | - Luisa Benussi
- NeuroBioGen Lab-Memory Clinic, IRCCS Istituto Centro San Giovanni di Dio Fatebenefratelli, Brescia, Italy
| | - Amalia C Bruni
- Regional Neurogenetic Centre, ASPCZ, Lamezia Terme, Italy
| | - Graziella Filippini
- Scientific Directorate, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milano, Italy
| | - Mariangela Farinotti
- Neuroepidemiology - Scientific Directorate, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milano, Italy
| | - Giorgio Giaccone
- Unit of Neurology V and Neuropathology, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milano, Italy
| | | | - Claudia Manzoni
- School of Pharmacy, University of Reading, Whiteknights, Reading, United Kingdom.,Department of Molecular Neuroscience, UCL Institute of Neurology, London, United Kingdom
| | - Raffaele Ferrari
- Department of Molecular Neuroscience, UCL Institute of Neurology, London, United Kingdom
| | - Fabrizio Tagliavini
- Scientific Directorate, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milano, Italy
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11
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Leija-Salazar M, Piette C, Proukakis C. Review: Somatic mutations in neurodegeneration. Neuropathol Appl Neurobiol 2018; 44:267-285. [PMID: 29369391 DOI: 10.1111/nan.12465] [Citation(s) in RCA: 62] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2017] [Accepted: 01/13/2018] [Indexed: 12/22/2022]
Abstract
Somatic mutations are postzygotic mutations which may lead to mosaicism, the presence of cells with genetic differences in an organism. Their role in cancer is well established, but detailed investigation in health and other diseases has only been recently possible. This has been empowered by the improvements of sequencing techniques, including single-cell sequencing, which can still be error-prone but is rapidly improving. Mosaicism appears relatively common in the human body, including the normal brain, probably arising in early development, but also potentially during ageing. In this review, we first discuss theoretical considerations and current evidence relevant to somatic mutations in the brain. We present a framework to explain how they may be integrated with current views on neurodegeneration, focusing mainly on sporadic late-onset neurodegenerative diseases (Parkinson's disease, Alzheimer's disease and amyotrophic lateral sclerosis). We review the relevant studies so far, with the first evidence emerging in Alzheimer's in particular. We also discuss the role of mosaicism in inherited neurodegenerative disorders, particularly somatic instability of tandem repeats. We summarize existing views and data to present a model whereby the time of origin and spatial distribution of relevant somatic mutations, combined with any additional risk factors, may partly determine the development and onset age of sporadic neurodegenerative diseases.
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Affiliation(s)
- M Leija-Salazar
- Department of Clinical Neuroscience, University College London Institute of Neurology, London, UK
| | - C Piette
- Department of Clinical Neuroscience, University College London Institute of Neurology, London, UK
| | - C Proukakis
- Department of Clinical Neuroscience, University College London Institute of Neurology, London, UK
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12
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Caneus J, Granic A, Rademakers R, Dickson DW, Coughlan CM, Chial HJ, Potter H. Mitotic defects lead to neuronal aneuploidy and apoptosis in frontotemporal lobar degeneration caused by MAPT mutations. Mol Biol Cell 2017; 29:575-586. [PMID: 29282277 PMCID: PMC6004587 DOI: 10.1091/mbc.e17-01-0031] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2017] [Revised: 12/08/2017] [Accepted: 12/22/2017] [Indexed: 01/01/2023] Open
Abstract
Mutant Tau (MAPT) can lead to frontotemporal lobar degeneration (FTLD). Previous studies associated MAPT mutations and altered function with aneuploidy and chromosome instability in human lymphocytes and in Drosophila development. Here we examine whether FTLD-causing mutations in human MAPT induce aneuploidy and apoptosis in the mammalian brain. First, aneuploidy was found in brain cells from MAPT mutant transgenic mice expressing FTLD mutant human MAPT. Then brain neurons from mice homozygous or heterozygous for the Tau (Mapt) null allele were found to exhibit increasing levels of aneuploidy with decreasing Tau gene dosage. To determine whether aneuploidy leads to neurodegeneration in FTLD, we measured aneuploidy and apoptosis in brain cells from patients with MAPT mutations and identified both increased aneuploidy and apoptosis in the same brain neurons and glia. To determine whether there is a direct relationship between MAPT-induced aneuploidy and apoptosis, we expressed FTLD-causing mutant forms of MAPT in karyotypically normal human cells and found that they cause aneuploidy and mitotic spindle defects that then result in apoptosis. Collectively, our findings reveal a neurodegenerative pathway in FTLD-MAPT in which neurons and glia exhibit mitotic spindle abnormalities, chromosome mis-segregation, and aneuploidy, which then lead to apoptosis.
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Affiliation(s)
- Julbert Caneus
- Department of Neurology, Rocky Mountain Alzheimer's Disease Center, University of Colorado School of Medicine, Aurora, CO 80045.,Linda Crnic Institute for Down Syndrome, University of Colorado School of Medicine, Aurora, CO 80045.,Neuroscience Program, University of Colorado, Anschutz Medical Campus, Aurora, CO 80045
| | - Antoneta Granic
- Department of Neurology, Rocky Mountain Alzheimer's Disease Center, University of Colorado School of Medicine, Aurora, CO 80045.,Department of Neurology, Rocky Mountain Alzheimer's Disease Center, University of Colorado School of Medicine, Aurora, CO 80045.,AGE Research Group, Institute of Neuroscience, Newcastle University, Newcastle upon Tyne NE4 5PL, United Kingdom.,Campus for Ageing and Vitality, Biomedical Research Building, Newcastle University, Newcastle upon Tyne NE4 5PL, United Kingdom.,NIHR Newcastle Biomedical Research Centre, Newcastle upon Tyne Hospitals NHS Foundation Trust and Newcastle University, Newcastle upon Tyne NE4 5PL, United Kingdom
| | - Rosa Rademakers
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL 32224
| | | | - Christina M Coughlan
- Department of Neurology, Rocky Mountain Alzheimer's Disease Center, University of Colorado School of Medicine, Aurora, CO 80045.,Department of Neurology, Rocky Mountain Alzheimer's Disease Center, University of Colorado School of Medicine, Aurora, CO 80045
| | - Heidi J Chial
- Department of Neurology, Rocky Mountain Alzheimer's Disease Center, University of Colorado School of Medicine, Aurora, CO 80045.,Department of Neurology, Rocky Mountain Alzheimer's Disease Center, University of Colorado School of Medicine, Aurora, CO 80045
| | - Huntington Potter
- Department of Neurology, Rocky Mountain Alzheimer's Disease Center, University of Colorado School of Medicine, Aurora, CO 80045 .,Linda Crnic Institute for Down Syndrome, University of Colorado School of Medicine, Aurora, CO 80045.,Neuroscience Program, University of Colorado, Anschutz Medical Campus, Aurora, CO 80045
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13
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Wang ZH, Liu P, Liu X, Manfredsson FP, Sandoval IM, Yu SP, Wang JZ, Ye K. Delta-Secretase Phosphorylation by SRPK2 Enhances Its Enzymatic Activity, Provoking Pathogenesis in Alzheimer's Disease. Mol Cell 2017; 67:812-825.e5. [PMID: 28826672 DOI: 10.1016/j.molcel.2017.07.018] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2017] [Revised: 06/28/2017] [Accepted: 07/19/2017] [Indexed: 01/06/2023]
Abstract
Delta-secretase, a lysosomal asparagine endopeptidase (AEP), simultaneously cleaves both APP and tau, controlling the onset of pathogenesis of Alzheimer's disease (AD). However, how this protease is post-translationally regulated remains unclear. Here we report that serine-arginine protein kinase 2 (SRPK2) phosphorylates delta-secretase and enhances its enzymatic activity. SRPK2 phosphorylates serine 226 on delta-secretase and accelerates its autocatalytic cleavage, leading to its cytoplasmic translocation and escalated enzymatic activities. Delta-secretase is highly phosphorylated in human AD brains, tightly correlated with SRPK2 activity. Overexpression of a phosphorylation mimetic (S226D) in young 3xTg mice strongly promotes APP and tau fragmentation and facilitates amyloid plaque deposits and neurofibrillary tangle (NFT) formation, resulting in cognitive impairment. Conversely, viral injection of the non-phosphorylatable mutant (S226A) into 5XFAD mice decreases APP and tau proteolytic cleavage, attenuates AD pathologies, and reverses cognitive defects. Our findings support that delta-secretase phosphorylation by SRPK2 plays a critical role in aggravating AD pathogenesis.
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Affiliation(s)
- Zhi-Hao Wang
- Department of Pathology and Laboratory Medicine, Emory University School of Medicine, Atlanta, GA 30322, USA; Department of Pathophysiology, Key Laboratory of Ministry of Education of Neurological Diseases, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Pai Liu
- Emory College of Arts and Sciences, Emory University, Atlanta, GA 30322, USA
| | - Xia Liu
- Department of Pathology and Laboratory Medicine, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - Fredric P Manfredsson
- Department of Translational Science and Molecular Medicine, Michigan State University, 333 Bostwick Avenue NE, Grand Rapids, MI 49503, USA
| | - Ivette M Sandoval
- Department of Translational Science and Molecular Medicine, Michigan State University, 333 Bostwick Avenue NE, Grand Rapids, MI 49503, USA
| | - Shan Ping Yu
- Department of Anesthesiology, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - Jian-Zhi Wang
- Department of Pathophysiology, Key Laboratory of Ministry of Education of Neurological Diseases, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China; Co-innovation Center of Neuroregeneration, Nantong 226001, China.
| | - Keqiang Ye
- Department of Pathology and Laboratory Medicine, Emory University School of Medicine, Atlanta, GA 30322, USA; Translational Center for Stem Cell Research, Tongji Hospital, Tongji University School of Medicine, Shanghai 200065, China.
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14
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Developmental Expression of 4-Repeat-Tau Induces Neuronal Aneuploidy in Drosophila Tauopathy Models. Sci Rep 2017; 7:40764. [PMID: 28112163 PMCID: PMC5256094 DOI: 10.1038/srep40764] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2016] [Accepted: 12/12/2016] [Indexed: 01/23/2023] Open
Abstract
Tau-mediated neurodegeneration in Alzheimer’s disease and tauopathies is generally assumed to start in a normally developed brain. However, several lines of evidence suggest that impaired Tau isoform expression during development could affect mitosis and ploidy in post-mitotic differentiated tissue. Interestingly, the relative expression levels of Tau isoforms containing either 3 (3R-Tau) or 4 repeats (4R-Tau) play an important role both during brain development and neurodegeneration. Here, we used genetic and cellular tools to study the link between 3R and 4R-Tau isoform expression, mitotic progression in neuronal progenitors and post-mitotic neuronal survival. Our results illustrated that the severity of Tau-induced adult phenotypes depends on 4R-Tau isoform expression during development. As recently described, we observed a mitotic delay in 4R-Tau expressing cells of larval eye discs and brains. Live imaging revealed that the spindle undergoes a cycle of collapse and recovery before proceeding to anaphase. Furthermore, we found a high level of aneuploidy in post-mitotic differentiated tissue. Finally, we showed that overexpression of wild type and mutant 4R-Tau isoform in neuroblastoma SH-SY5Y cell lines is sufficient to induce monopolar spindles. Taken together, our results suggested that neurodegeneration could be in part linked to neuronal aneuploidy caused by 4R-Tau expression during brain development.
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15
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Potter H, Granic A, Caneus J. Role of Trisomy 21 Mosaicism in Sporadic and Familial Alzheimer's Disease. Curr Alzheimer Res 2016; 13:7-17. [PMID: 26651340 DOI: 10.2174/156720501301151207100616] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2015] [Revised: 05/13/2015] [Accepted: 08/30/2015] [Indexed: 02/07/2023]
Abstract
Trisomy 21 and the consequent extra copy of the amyloid precursor protein (APP) gene and increased beta-amyloid (Aβ) peptide production underlie the universal development of Alzheimer's disease (AD) pathology and high risk of AD dementia in people with Down syndrome (DS). Trisomy 21 and other forms of aneuploidy also arise among neurons and peripheral cells in both sporadic and familial AD and in mouse and cell models thereof, reinforcing the conclusion that AD and DS are two sides of the same coin. The demonstration that 90% of the neurodegeneration in AD can be attributed to the selective loss of aneuploid neurons generated over the course of the disease indicates that aneuploidy is an essential feature of the pathogenic pathway leading to the depletion of neuronal cell populations. Trisomy 21 mosaicism also occurs in neurons and other cells from patients with Niemann-Pick C1 disease and from patients with familial or sporadic frontotemporal lobar degeneration (FTLD), as well as in their corresponding mouse and cell models. Biochemical studies have shown that Aβ induces mitotic spindle defects, chromosome mis-segregation, and aneuploidy in cultured cells by inhibiting specific microtubule motors required for mitosis. These data indicate that neuronal trisomy 21 and other types of aneuploidy characterize and likely contribute to multiple neurodegenerative diseases and are a valid target for therapeutic intervention. For example, reducing extracellular calcium or treating cells with lithium chloride (LiCl) blocks the induction of trisomy 21 by Aβ. The latter finding is relevant in light of recent reports of a lowered risk of dementia in bipolar patients treated with LiCl and in the stabilization of cognition in AD patients treated with LiCl.
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Affiliation(s)
- Huntington Potter
- Department of Neurology and Linda Crnic Institute for Down Syndrome, 12700 E. 19th Ave room 4010, mail stop 8608, Aurora CO 80045, USA.
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16
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Arendt T, Stieler JT, Holzer M. Tau and tauopathies. Brain Res Bull 2016; 126:238-292. [DOI: 10.1016/j.brainresbull.2016.08.018] [Citation(s) in RCA: 333] [Impact Index Per Article: 41.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2016] [Revised: 08/31/2016] [Accepted: 08/31/2016] [Indexed: 12/11/2022]
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17
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Bougé AL, Parmentier ML. Tau excess impairs mitosis and kinesin-5 function, leading to aneuploidy and cell death. Dis Model Mech 2016; 9:307-19. [PMID: 26822478 PMCID: PMC4833329 DOI: 10.1242/dmm.022558] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2015] [Accepted: 01/21/2016] [Indexed: 12/31/2022] Open
Abstract
In neurodegenerative diseases such as Alzheimer's disease (AD), cell cycle defects and associated aneuploidy have been described. However, the importance of these defects in the physiopathology of AD and the underlying mechanistic processes are largely unknown, in particular with respect to the microtubule (MT)-binding protein Tau, which is found in excess in the brain and cerebrospinal fluid of affected individuals. Although it has long been known that Tau is phosphorylated during mitosis to generate a lower affinity for MTs, there is, to our knowledge, no indication that an excess of this protein could affect mitosis. Here, we studied the effect of an excess of human Tau (hTau) protein on cell mitosis in vivo. Using the Drosophila developing wing disc epithelium as a model, we show that an excess of hTau induces a mitotic arrest, with the presence of monopolar spindles. This mitotic defect leads to aneuploidy and apoptotic cell death. We studied the mechanism of action of hTau and found that the MT-binding domain of hTau is responsible for these defects. We also demonstrate that the effects of hTau occur via the inhibition of the function of the kinesin Klp61F, the Drosophila homologue of kinesin-5 (also called Eg5 or KIF11). We finally show that this deleterious effect of hTau is also found in other Drosophila cell types (neuroblasts) and tissues (the developing eye disc), as well as in human HeLa cells. By demonstrating that MT-bound Tau inhibits the Eg5 kinesin and cell mitosis, our work provides a new framework to consider the role of Tau in neurodegenerative diseases. Drosophila Collection: We show that Tau, a microtubule-binding protein involved in many neurodegenerative diseases, impairs mitosis when in excess. We show that this occurs via the inhibition of the kinesin-5 mitotic motor.
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Affiliation(s)
- Anne-Laure Bougé
- Department of Neurosciences, Institut de Génomique Fonctionnelle, CNRS-UMR5203, INSERM-U1191, Université Montpellier, 141 Rue de la Cardonille, Montpellier F-34094, Cedex 5, France
| | - Marie-Laure Parmentier
- Department of Neurosciences, Institut de Génomique Fonctionnelle, CNRS-UMR5203, INSERM-U1191, Université Montpellier, 141 Rue de la Cardonille, Montpellier F-34094, Cedex 5, France
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18
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Rossi G, Tagliavini F. Frontotemporal lobar degeneration: old knowledge and new insight into the pathogenetic mechanisms of tau mutations. Front Aging Neurosci 2015; 7:192. [PMID: 26528178 PMCID: PMC4604311 DOI: 10.3389/fnagi.2015.00192] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2015] [Accepted: 09/22/2015] [Indexed: 12/11/2022] Open
Abstract
Frontotemporal lobar degeneration (FTLD) is a group of heterogeneous neurodegenerative diseases which includes tauopathies. In the central nervous system (CNS) tau is the major microtubule-associated protein (MAP) of neurons, promoting assembly and stabilization of microtubules (MTs) required for morphogenesis and axonal transport. Primary tauopathies are characterized by deposition of abnormal fibrils of tau in neuronal and glial cells, leading to neuronal death, brain atrophy and eventually dementia. In genetic tauopathies mutations of tau gene impair the ability of tau to bind to MTs, alter the normal ratio among tau isoforms and favor fibril formation. Recently, additional functions have been ascribed to tau and different pathogenetic mechanisms are then emerging. In fact, a role of tau in DNA protection and genome stability has been reported and chromosome aberrations have been found associated with tau mutations. Furthermore, newly structurally and functionally characterized mutations have suggested novel pathological features, such as a tendency to form oligomeric rather than fibrillar aggregates. Tau mutations affecting axonal transport and plasma membrane interaction have also been described. In this article, we will review the pathogenetic mechanisms underlying tau mutations, focusing in particular on the less common aspects, so far poorly investigated.
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Affiliation(s)
- Giacomina Rossi
- Division of Neurology V and Neuropathology, Fondazione IRCCS Istituto Neurologico Carlo Besta Milano, Italy
| | - Fabrizio Tagliavini
- Division of Neurology V and Neuropathology, Fondazione IRCCS Istituto Neurologico Carlo Besta Milano, Italy
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The Role of MAPT in Neurodegenerative Diseases: Genetics, Mechanisms and Therapy. Mol Neurobiol 2015; 53:4893-904. [PMID: 26363795 DOI: 10.1007/s12035-015-9415-8] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2015] [Accepted: 09/01/2015] [Indexed: 12/11/2022]
Abstract
Microtubule-associated protein tau (MAPT) is a gene responsible for encoding tau protein, which is tightly implicated in keeping the function of microtubules and axonal transport. Hyperphosphorylated tau protein participates in the formation of neurofibrillary tangles (NFTs), which characterize many neurodegenerative disorders termed tauopathies. Genome-wide association studies (GWAS) have demonstrated numerous single nucleotide polymorphisms (SNPs) located in MAPT associated with various neurodegenerative diseases. Thus, it has been presumed that MAPT plays a crucial role in pathogenesis of neurodegeneration via affecting the structure and function of tau. Here, we review the advanced studies to summarize the biochemical properties of MAPT and its encoded protein, as well as the genetics and epigenetics of MAPT in neurodegeneration. Finally, given the potential mechanisms of MAPT to neurodegeneration pathogenesis, targeting MAPT and tau might present significant treatments of MAPT mutation-related neurodegeneration. Affirmatively, the identification of MAPT is extremely beneficial for improving our understanding of the pathogenesis of various neurodegenerative diseases and developing the mechanism-based therapies.
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20
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Genomic Copy Number Variation Affecting Genes Involved in the Cell Cycle Pathway: Implications for Somatic Mosaicism. Int J Genomics 2015; 2015:757680. [PMID: 26421275 PMCID: PMC4569762 DOI: 10.1155/2015/757680] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2015] [Accepted: 07/27/2015] [Indexed: 12/20/2022] Open
Abstract
Somatic genome variations (mosaicism) seem to represent a common mechanism for human intercellular/interindividual diversity in health and disease. However, origins and mechanisms of somatic mosaicism remain a matter of conjecture. Recently, it has been hypothesized that zygotic genomic variation naturally occurring in humans is likely to predispose to nonheritable genetic changes (aneuploidy) acquired during the lifetime through affecting cell cycle regulation, genome stability maintenance, and related pathways. Here, we have evaluated genomic copy number variation (CNV) in genes implicated in the cell cycle pathway (according to Kyoto Encyclopedia of Genes and Genomes/KEGG) within a cohort of patients with intellectual disability, autism, and/or epilepsy, in which the phenotype was not associated with genomic rearrangements altering this pathway. Benign CNVs affecting 20 genes of the cell cycle pathway were detected in 161 out of 255 patients (71.6%). Among them, 62 individuals exhibited >2 CNVs affecting the cell cycle pathway. Taking into account the number of individuals demonstrating CNV of these genes, a support for this hypothesis appears to be presented. Accordingly, we speculate that further studies of CNV burden across the genes implicated in related pathways might clarify whether zygotic genomic variation generates somatic mosaicism in health and disease.
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