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Salaikumaran M, Gopal PP. Rational Design of TDP-43 Derived α-Helical Peptide Inhibitors: An In Silico Strategy to Prevent TDP-43 Aggregation in Neurodegenerative Disorders. ACS Chem Neurosci 2024; 15:1096-1109. [PMID: 38466778 PMCID: PMC10959110 DOI: 10.1021/acschemneuro.3c00659] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2023] [Revised: 01/21/2024] [Accepted: 02/19/2024] [Indexed: 03/13/2024] Open
Abstract
TDP-43, an essential RNA/DNA-binding protein, is central to the pathology of neurodegenerative diseases, such as amyotrophic lateral sclerosis and frontotemporal dementia. Pathological mislocalization and aggregation of TDP-43 disrupt RNA splicing, mRNA stability, and mRNA transport, thereby impairing neuronal function and survival. The formation of amyloid-like TDP-43 filaments is largely facilitated by the destabilization of an α-helical segment within the disordered C-terminal region. In this study, we hypothesized that preventing the destabilization of the α-helical domain could potentially halt the growth of these pathological filaments. To explore this, we utilized a range of in silico techniques to design and evaluate peptide-based therapeutics that bind to pathological TDP-43 amyloid-like filament crystal structures and resist β sheet conversion. Our computational approaches, including biophysical and secondary structure property prediction, molecular docking, 3D structure prediction, and molecular dynamics simulations, were used to assess the structure, stability, and binding affinity of these peptides in relation to pathological TDP-43 filaments. The results of our in silico analyses identified a selection of promising peptides which displayed a stable α-helical structure, exhibited an increased number of intramolecular hydrogen bonds within the helical domain, and demonstrated high binding affinities for pathological TDP-43 amyloid-like filaments. Molecular dynamics simulations provided further support for the structural and thermodynamic stability of these peptides, as they exhibited lower root-mean-square deviation and more favorable free energy landscapes over 300 ns. These findings establish α-helical propensity peptides as potential lead molecules for the development of novel therapeutics against TDP-43 aggregation. This structure-based computational approach for the rational design of peptide inhibitors opens a new direction in the search for effective interventions for ALS, FTD, and other related neurodegenerative diseases. The peptides identified as the most promising candidates in this study are currently subject to further testing and validation through both in vitro and in vivo experiments.
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Affiliation(s)
- Muthu
Raj Salaikumaran
- Department
of Pathology, Yale School of Medicine, New Haven, Connecticut 06520, United States
| | - Pallavi P. Gopal
- Department
of Pathology, Yale School of Medicine, New Haven, Connecticut 06520, United States
- Program
in Cellular Neuroscience, Neurodegeneration, and Repair, Yale School of Medicine, New Haven, Connecticut 06520-8055, United States
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2
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Antón R, Treviño MÁ, Pantoja-Uceda D, Félix S, Babu M, Cabrita EJ, Zweckstetter M, Tinnefeld P, Vera AM, Oroz J. Alternative low-populated conformations prompt phase transitions in polyalanine repeat expansions. Nat Commun 2024; 15:1925. [PMID: 38431667 PMCID: PMC10908835 DOI: 10.1038/s41467-024-46236-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2023] [Accepted: 02/19/2024] [Indexed: 03/05/2024] Open
Abstract
Abnormal trinucleotide repeat expansions alter protein conformation causing malfunction and contribute to a significant number of incurable human diseases. Scarce structural insights available on disease-related homorepeat expansions hinder the design of effective therapeutics. Here, we present the dynamic structure of human PHOX2B C-terminal fragment, which contains the longest polyalanine segment known in mammals. The major α-helical conformation of the polyalanine tract is solely extended by polyalanine expansions in PHOX2B, which are responsible for most congenital central hypoventilation syndrome cases. However, polyalanine expansions in PHOX2B additionally promote nascent homorepeat conformations that trigger length-dependent phase transitions into solid condensates that capture wild-type PHOX2B. Remarkably, HSP70 and HSP90 chaperones specifically seize PHOX2B alternative conformations preventing phase transitions. The precise observation of emerging polymorphs in expanded PHOX2B postulates unbalanced phase transitions as distinct pathophysiological mechanisms in homorepeat expansion diseases, paving the way towards the search of therapeutics modulating biomolecular condensates in central hypoventilation syndrome.
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Affiliation(s)
- Rosa Antón
- Instituto de Química Física Blas Cabrera (IQF), CSIC, E-28006, Madrid, Spain
| | - Miguel Á Treviño
- Instituto de Química Física Blas Cabrera (IQF), CSIC, E-28006, Madrid, Spain
| | - David Pantoja-Uceda
- Instituto de Química Física Blas Cabrera (IQF), CSIC, E-28006, Madrid, Spain
| | - Sara Félix
- Associate Laboratory i4HB - Institute for Health and Bioeconomy, NOVA School of Science and Technology, Universidade NOVA de Lisboa, 2819-516, Caparica, Portugal
- UCIBIO, Department of Chemistry, NOVA School of Science and Technology, Universidade NOVA de Lisboa, 2819-516, Caparica, Portugal
| | - María Babu
- German Center for Neurodegenerative Diseases (DZNE), 37075, Göttingen, Germany
| | - Eurico J Cabrita
- Associate Laboratory i4HB - Institute for Health and Bioeconomy, NOVA School of Science and Technology, Universidade NOVA de Lisboa, 2819-516, Caparica, Portugal
- UCIBIO, Department of Chemistry, NOVA School of Science and Technology, Universidade NOVA de Lisboa, 2819-516, Caparica, Portugal
| | - Markus Zweckstetter
- German Center for Neurodegenerative Diseases (DZNE), 37075, Göttingen, Germany
- Department for NMR-based Structural Biology, Max Planck Institute for Multidisciplinary Sciences, 37077, Göttingen, Germany
| | - Philip Tinnefeld
- Department of Chemistry and Center for NanoScience, Ludwig-Maximilians-Universität München, München, 81377, Germany
| | - Andrés M Vera
- Department of Chemistry and Center for NanoScience, Ludwig-Maximilians-Universität München, München, 81377, Germany
| | - Javier Oroz
- Instituto de Química Física Blas Cabrera (IQF), CSIC, E-28006, Madrid, Spain.
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3
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Chang HY, Wang IF. Restoring functional TDP-43 oligomers in ALS and laminopathic cellular models through baicalein-induced reconfiguration of TDP-43 aggregates. Sci Rep 2024; 14:4620. [PMID: 38409193 PMCID: PMC10897466 DOI: 10.1038/s41598-024-55229-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2023] [Accepted: 02/21/2024] [Indexed: 02/28/2024] Open
Abstract
A group of misfolded prone-to-aggregate domains in disease-causing proteins has recently been shown to adopt unique conformations that play a role in fundamental biological processes. These processes include the formation of membrane-less sub-organelles, alternative splicing, and gene activation and silencing. The cellular responses are regulated by the conformational switching of prone-to-aggregate domains, independently of changes in RNA or protein expression levels. Given this, targeting the misfolded states of disease-causing proteins to redirect them towards their physiological conformations is emerging as an effective therapeutic strategy for diseases caused by protein misfolding. In our study, we successfully identified baicalein as a potent structure-correcting agent. Our findings demonstrate that baicalein can reconfigure existing TDP-43 aggregates into an oligomeric state both in vitro and in disease cells. This transformation effectively restores the bioactivity of misfolded TDP-43 proteins in cellular models of ALS and premature aging in progeria. Impressively, in progeria cells where defective lamin A interferes with TDP-43-mediated exon skipping, the formation of pathological TDP-43 aggregates is promoted. Baicalein, however, restores the functionality of TDP-43 and mitigates nuclear shape defects in these laminopathic cells. This establishes a connection between lamin A and TDP-43 in the context of aging. Our findings suggest that targeting physiological TDP-43 oligomers could offer a promising therapeutic avenue for treating aging-associated disorders.
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Affiliation(s)
- Hsiang-Yu Chang
- Garage Brain Science, B201, Central Taiwan Innovation Campus, Ministry of Economic Affairs, Nantou City, 540219, Taiwan
- Yee Fan Med Inc, Temple City, CA, 91780, USA
- SABNP Lab, Univ Evry, INSERM U1204, Université Paris-Saclay, 91025, Evry, France
| | - I-Fan Wang
- Garage Brain Science, B201, Central Taiwan Innovation Campus, Ministry of Economic Affairs, Nantou City, 540219, Taiwan.
- Yee Fan Med Inc, Temple City, CA, 91780, USA.
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4
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Qassim HM, Seyedalipour B, Baziyar P, Ahamady-Asbchin S. Polyphenolic flavonoid compounds act as the inhibitory potential of aggregation process: Implications for the prevention and therapeutics against FALS-associated D101G SOD1 mutant. Comput Biol Chem 2023; 107:107967. [PMID: 37844376 DOI: 10.1016/j.compbiolchem.2023.107967] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2023] [Revised: 09/30/2023] [Accepted: 10/04/2023] [Indexed: 10/18/2023]
Abstract
Aggregation of proteins is a biological phenomenon caused by misfolded proteins. Human superoxide dismutase (hSOD1) misfolding and aggregation underlie the neurological illness amyotrophic lateral sclerosis (ALS). The most significant contributing factor to ALS is genetic point mutations in SOD1. particularly, D101G mutant is the most harmful because it significantly reduces the life expectancy of patients. Subsequently, the use of natural polyphenolic flavonoids is strongly recommended to reduce the amyloidogenic behavior of protopathic proteins. In this study, using computational parameters such as protein-ligand interaction and molecular dynamics (MD) simulation analyses, we are trying to identify a pharmacodynamically promising flavonoid compound that can effectively inhibit the pathogenic behavior of the D101G mutant. Epigallocatechin-gallate (EGCG), Hesperidin, Isorhamnetin, and Diosmetin were identified as potential leads in a preliminary screening of flavonoids to anti-amyloid action. The results of MD showed that the binding of flavonoids to D101G mutant caused changes in stability, hydrophobicity of protein, and flexibility, as well as significantly led to the restoration of lost hydrogen bonds. Secondary structure analysis showed that protein destabilization and the increased propensity of β-sheet caused by the mutation were restored to the wild-type state upon binding of flavonoids. Besides, to differentiate aggregation, we elucidated alterations in the free energy landscape (FEL) and dynamic cross-correlation matrix (DCCM) of WT-SOD1 and mutant (unbound /bound) states. Among flavonoids, Epigallocatechin-gallate and Hesperidin had the most therapeutic efficacy against the D101G mutant. Therefore, Epigallocatechin-gallate and Hesperidin promise considerable therapeutic potential to develop highly effective inhibitors in reducing fatal and irreversible ALS.
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Affiliation(s)
- Hussein Maitham Qassim
- Department of Molecular and Cell Biology, Faculty of Basic Science, University of Mazandaran, Babolsar, Iran
| | - Bagher Seyedalipour
- Department of Molecular and Cell Biology, Faculty of Basic Science, University of Mazandaran, Babolsar, Iran.
| | - Payam Baziyar
- Department of Molecular and Cell Biology, Faculty of Basic Science, University of Mazandaran, Babolsar, Iran
| | - Salman Ahamady-Asbchin
- Department of Microbiology, Faculty of Basic Science, University of Mazandaran, Babolsar, Iran
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5
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Salaikumaran MR, Gopal PP. Rational Design of TDP-43 Derived α-Helical Peptide Inhibitors: an In-Silico Strategy to Prevent TDP-43 Aggregation in Neurodegenerative Disorders. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.10.26.564235. [PMID: 37961353 PMCID: PMC10635017 DOI: 10.1101/2023.10.26.564235] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/15/2023]
Abstract
TDP-43, an essential RNA/DNA-binding protein, is central to the pathology of neurodegenerative diseases such as Amyotrophic Lateral Sclerosis and Frontotemporal Dementia. Pathological mislocalization and aggregation of TDP-43 disrupts RNA splicing, mRNA stability, and mRNA transport, thereby impairing neuronal function and survival. The formation of amyloid-like TDP-43 filaments is largely facilitated by the destabilization of an α-helical segment within the disordered C-terminal region. In this study, we hypothesized that preventing the destabilization of the α-helical domain could potentially halt the growth of these pathological filaments. To explore this, we utilized a range of in-silico techniques to design and evaluate peptide-based therapeutics. Various pathological TDP-43 amyloid-like filament crystal structures were selected for their potential to inhibit the binding of additional TDP-43 monomers to the growing filaments. Our computational approaches included biophysical and secondary structure property prediction, molecular docking, 3D structure prediction, and molecular dynamics simulations. Through these techniques, we were able to assess the structure, stability, and binding affinity of these peptides in relation to pathological TDP-43 filaments. The results of our in-silico analyses identified a selection of promising peptides, which displayed a stable α-helical structure, exhibited an increased number of intramolecular hydrogen bonds within the helical domain, and demonstrated high binding affinities for pathological TDP-43 amyloid-like filaments. Additionally, molecular dynamics simulations provided further support for the stability of these peptides, as they exhibited lower root mean square deviations in their helical propensity over 100ns. These findings establish α-helical propensity peptides as potential lead molecules for the development of novel therapeutics against TDP-43 aggregation. This structure-based computational approach for rational design of peptide inhibitors opens a new direction in the search for effective interventions for ALS, FTD, and other related neurodegenerative diseases. The peptides identified as the most promising candidates in this study are currently subject to further testing and validation through both in vitro and in vivo experiments.
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6
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Pérez‐Berlanga M, Wiersma VI, Zbinden A, De Vos L, Wagner U, Foglieni C, Mallona I, Betz KM, Cléry A, Weber J, Guo Z, Rigort R, de Rossi P, Manglunia R, Tantardini E, Sahadevan S, Stach O, Hruska‐Plochan M, Allain FH, Paganetti P, Polymenidou M. Loss of TDP-43 oligomerization or RNA binding elicits distinct aggregation patterns. EMBO J 2023; 42:e111719. [PMID: 37431963 PMCID: PMC10476175 DOI: 10.15252/embj.2022111719] [Citation(s) in RCA: 11] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2022] [Revised: 06/02/2023] [Accepted: 06/12/2023] [Indexed: 07/12/2023] Open
Abstract
Aggregation of the RNA-binding protein TAR DNA-binding protein 43 (TDP-43) is the key neuropathological feature of neurodegenerative diseases, including amyotrophic lateral sclerosis (ALS) and frontotemporal lobar degeneration (FTLD). In physiological conditions, TDP-43 is predominantly nuclear, forms oligomers, and is contained in biomolecular condensates assembled by liquid-liquid phase separation (LLPS). In disease, TDP-43 forms cytoplasmic or intranuclear inclusions. How TDP-43 transitions from physiological to pathological states remains poorly understood. Using a variety of cellular systems to express structure-based TDP-43 variants, including human neurons and cell lines with near-physiological expression levels, we show that oligomerization and RNA binding govern TDP-43 stability, splicing functionality, LLPS, and subcellular localization. Importantly, our data reveal that TDP-43 oligomerization is modulated by RNA binding. By mimicking the impaired proteasomal activity observed in ALS/FTLD patients, we found that monomeric TDP-43 forms inclusions in the cytoplasm, whereas its RNA binding-deficient counterpart aggregated in the nucleus. These differentially localized aggregates emerged via distinct pathways: LLPS-driven aggregation in the nucleus and aggresome-dependent inclusion formation in the cytoplasm. Therefore, our work unravels the origins of heterogeneous pathological species reminiscent of those occurring in TDP-43 proteinopathy patients.
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Affiliation(s)
| | - Vera I Wiersma
- Department of Quantitative BiomedicineUniversity of ZurichZurichSwitzerland
| | - Aurélie Zbinden
- Department of Quantitative BiomedicineUniversity of ZurichZurichSwitzerland
| | - Laura De Vos
- Department of Quantitative BiomedicineUniversity of ZurichZurichSwitzerland
| | - Ulrich Wagner
- Department of Pathology and Molecular Pathology, University Hospital ZurichUniversity of ZurichZurichSwitzerland
| | - Chiara Foglieni
- Neurodegeneration Research Group, Laboratory for Biomedical Neurosciences, Neurocenter of Southern Switzerland, Ente Ospedaliero CantonaleBellinzonaSwitzerland
| | - Izaskun Mallona
- Department of Quantitative BiomedicineUniversity of ZurichZurichSwitzerland
| | - Katharina M Betz
- Department of Quantitative BiomedicineUniversity of ZurichZurichSwitzerland
| | - Antoine Cléry
- Department of Biology, Institute of BiochemistryETH ZurichZurichSwitzerland
| | - Julien Weber
- Department of Quantitative BiomedicineUniversity of ZurichZurichSwitzerland
| | - Zhongning Guo
- Department of Quantitative BiomedicineUniversity of ZurichZurichSwitzerland
| | - Ruben Rigort
- Department of Quantitative BiomedicineUniversity of ZurichZurichSwitzerland
| | - Pierre de Rossi
- Department of Quantitative BiomedicineUniversity of ZurichZurichSwitzerland
| | - Ruchi Manglunia
- Department of Quantitative BiomedicineUniversity of ZurichZurichSwitzerland
| | - Elena Tantardini
- Department of Quantitative BiomedicineUniversity of ZurichZurichSwitzerland
| | - Sonu Sahadevan
- Department of Quantitative BiomedicineUniversity of ZurichZurichSwitzerland
| | - Oliver Stach
- Department of BiochemistryUniversity of ZurichZurichSwitzerland
| | | | | | - Paolo Paganetti
- Neurodegeneration Research Group, Laboratory for Biomedical Neurosciences, Neurocenter of Southern Switzerland, Ente Ospedaliero CantonaleBellinzonaSwitzerland
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7
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Kanekura K, Kuroda M. How can we interpret the relationship between liquid-liquid phase separation and amyotrophic lateral sclerosis? J Transl Med 2022; 102:912-918. [PMID: 36775420 DOI: 10.1038/s41374-022-00791-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2022] [Accepted: 04/12/2022] [Indexed: 01/08/2023] Open
Abstract
One of the critical definitions of neurodegenerative diseases is the formation of insoluble intracellular inclusion body. These inclusions are found in various neurodegenerative diseases such as Alzheimer's disease, amyotrophic lateral sclerosis (ALS), Huntington's disease, Parkinson's disease, and frontotemporal dementia (FTD). Each inclusion body contains disease-specific proteins and is also resistant to common detergent treatments. These aggregates are generally ubiquitinated and thus recognized as misfolded by the organism. They are observed in residual neurons at the affected sites in each disease, suggesting a contribution to disease pathogenesis. The molecular mechanisms for the formation of these inclusion bodies remain unclear. Some proteins, such as superoxide dismutase 1 (SOD1) mutant that causes familial ALS, are highly aggregative due to altered folding caused by point mutations. Still, the aggregates observed in neurodegenerative diseases contain wild-type proteins. In recent years, it has been reported that the proteins responsible for neurodegenerative diseases undergo liquid-liquid phase separation (LLPS). In particular, the ALS/FTD causative proteins such as TAR DNA-binding protein 43 kDa (TDP-43) and fused-in-sarcoma (FUS) undergo LLPS. LLPS increases the local concentration of these proteins, and these proteins eventually change their phase from liquid to solid (liquid-solid phase transition) due to abnormal folding during repetitive separation cycles into two phases and recovery to one phase. In addition to the inclusion body formation, sequestration of essential proteins into the LLPS droplets or changes in the LLPS status can directly impair neural functions and cause diseases. In this review, we will discuss the relationship between the LLPS observed in ALS causative proteins and the pathogenesis of the disease and outline potential therapeutic approaches.
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Affiliation(s)
- Kohsuke Kanekura
- Department of Molecular Pathology, Tokyo Medical University, 6-1-1 Shinjuku, Shinjuku-ku, Tokyo, 160-8402, Japan.
| | - Masahiko Kuroda
- Department of Molecular Pathology, Tokyo Medical University, 6-1-1 Shinjuku, Shinjuku-ku, Tokyo, 160-8402, Japan
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8
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EGCG Promotes FUS Condensate Formation in a Methylation-Dependent Manner. Cells 2022; 11:cells11040592. [PMID: 35203243 PMCID: PMC8870583 DOI: 10.3390/cells11040592] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2021] [Revised: 02/02/2022] [Accepted: 02/05/2022] [Indexed: 11/17/2022] Open
Abstract
Millions of people worldwide are affected by neurodegenerative diseases (NDs), and to date, no effective treatment has been reported. The hallmark of these diseases is the formation of pathological aggregates and fibrils in neural cells. Many studies have reported that catechins, polyphenolic compounds found in a variety of plants, can directly interact with amyloidogenic proteins, prevent the formation of toxic aggregates, and in turn play neuroprotective roles. Besides harboring amyloidogenic domains, several proteins involved in NDs possess arginine-glycine/arginine-glycine-glycine (RG/RGG) regions that contribute to the formation of protein condensates. Here, we aimed to assess whether epigallocatechin gallate (EGCG) can play a role in neuroprotection via direct interaction with such RG/RGG regions. We show that EGCG directly binds to the RG/RGG region of fused in sarcoma (FUS) and that arginine methylation enhances this interaction. Unexpectedly, we found that low micromolar amounts of EGCG were sufficient to restore RNA-dependent condensate formation of methylated FUS, whereas, in the absence of EGCG, no phase separation could be observed. Our data provide new mechanistic roles of EGCG in the regulation of phase separation of RG/RGG-containing proteins, which will promote understanding of the intricate function of EGCG in cells.
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9
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Lee S, Jo M, Lee HE, Jeon YM, Kim S, Kwon Y, Woo J, Han S, Mun JY, Kim HJ. HEXA-018, a Novel Inducer of Autophagy, Rescues TDP-43 Toxicity in Neuronal Cells. Front Pharmacol 2021; 12:747975. [PMID: 34925009 PMCID: PMC8675103 DOI: 10.3389/fphar.2021.747975] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2021] [Accepted: 11/05/2021] [Indexed: 11/13/2022] Open
Abstract
The autophagy-lysosomal pathway is an essential cellular mechanism that degrades aggregated proteins and damaged cellular components to maintain cellular homeostasis. Here, we identified HEXA-018, a novel compound containing a catechol derivative structure, as a novel inducer of autophagy. HEXA-018 increased the LC3-I/II ratio, which indicates activation of autophagy. Consistent with this result, HEXA-018 effectively increased the numbers of autophagosomes and autolysosomes in neuronal cells. We also found that the activation of autophagy by HEXA-018 is mediated by the AMPK-ULK1 pathway in an mTOR-independent manner. We further showed that ubiquitin proteasome system impairment- or oxidative stress-induced neurotoxicity was significantly reduced by HEXA-018 treatment. Moreover, oxidative stress-induced mitochondrial dysfunction was strongly ameliorated by HEXA-018 treatment. In addition, we investigated the efficacy of HEXA-018 in models of TDP-43 proteinopathy. HEXA-018 treatment mitigated TDP-43 toxicity in cultured neuronal cell lines and Drosophila. Our data indicate that HEXA-018 could be a new drug candidate for TDP-43-associated neurodegenerative diseases.
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Affiliation(s)
- Shinrye Lee
- Dementia Research Group, Korea Brain Research Institute (KBRI), Daegu, South Korea
| | - Myungjin Jo
- Dementia Research Group, Korea Brain Research Institute (KBRI), Daegu, South Korea
| | - Hye Eun Lee
- Neural Circuit Research Group, Korea Brain Research Institute (KBRI), Daegu, South Korea
| | - Yu-Mi Jeon
- Dementia Research Group, Korea Brain Research Institute (KBRI), Daegu, South Korea
| | - Seyeon Kim
- Dementia Research Group, Korea Brain Research Institute (KBRI), Daegu, South Korea.,Department of Brain and Cognitive Sciences, DGIST, Daegu, South Korea
| | - Younghwi Kwon
- Dementia Research Group, Korea Brain Research Institute (KBRI), Daegu, South Korea.,Department of Brain and Cognitive Sciences, DGIST, Daegu, South Korea
| | - Junghwa Woo
- Dementia Research Group, Korea Brain Research Institute (KBRI), Daegu, South Korea
| | - Shin Han
- Hexa Pharmatec, Ansan-si, South Korea
| | - Ji Young Mun
- Neural Circuit Research Group, Korea Brain Research Institute (KBRI), Daegu, South Korea
| | - Hyung-Jun Kim
- Dementia Research Group, Korea Brain Research Institute (KBRI), Daegu, South Korea
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10
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Novak V, Rogelj B, Župunski V. Therapeutic Potential of Polyphenols in Amyotrophic Lateral Sclerosis and Frontotemporal Dementia. Antioxidants (Basel) 2021; 10:antiox10081328. [PMID: 34439576 PMCID: PMC8389294 DOI: 10.3390/antiox10081328] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2021] [Revised: 08/11/2021] [Accepted: 08/20/2021] [Indexed: 12/11/2022] Open
Abstract
Amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD) are severe neurodegenerative disorders that belong to a common disease spectrum. The molecular and cellular aetiology of the spectrum is a highly complex encompassing dysfunction in many processes, including mitochondrial dysfunction and oxidative stress. There is a paucity of treatment options aside from therapies with subtle effects on the post diagnostic lifespan and symptom management. This presents great interest and necessity for the discovery and development of new compounds and therapies with beneficial effects on the disease. Polyphenols are secondary metabolites found in plant-based foods and are well known for their antioxidant activity. Recent research suggests that they also have a diverse array of neuroprotective functions that could lead to better treatments for neurodegenerative diseases. We present an overview of the effects of various polyphenols in cell line and animal models of ALS/FTD. Furthermore, possible mechanisms behind actions of the most researched compounds (resveratrol, curcumin and green tea catechins) are discussed.
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Affiliation(s)
- Valentina Novak
- Chair of Biochemistry, Faculty of Chemistry and Chemical Technology, University of Ljubljana, SI-1000 Ljubljana, Slovenia; (V.N.); (B.R.)
| | - Boris Rogelj
- Chair of Biochemistry, Faculty of Chemistry and Chemical Technology, University of Ljubljana, SI-1000 Ljubljana, Slovenia; (V.N.); (B.R.)
- Department of Biotechnology, Jozef Stefan Institute, SI-1000 Ljubljana, Slovenia
| | - Vera Župunski
- Chair of Biochemistry, Faculty of Chemistry and Chemical Technology, University of Ljubljana, SI-1000 Ljubljana, Slovenia; (V.N.); (B.R.)
- Correspondence:
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11
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Strategies in the design and development of (TAR) DNA-binding protein 43 (TDP-43) binding ligands. Eur J Med Chem 2021; 225:113753. [PMID: 34388383 DOI: 10.1016/j.ejmech.2021.113753] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2021] [Revised: 07/16/2021] [Accepted: 08/05/2021] [Indexed: 01/09/2023]
Abstract
The human transactive responsive (TAR) DNA-binding protein 43 (TDP-43) is involved in a number of physiological processes in the body. Its primary function involves RNA regulation. The TDP-43 protein is also involved in many diseases such as amyotrophic lateral sclerosis (ALS), frontotemporal dementia (FTD), Alzheimer's disease (AD), Parkinson's disease (PD) and even cancers. These TDP-43 mediated diseases are collectively called as TDP-43 proteinopathies. Intense research in the last decade has increased our understanding on TDP-43 structure and function in biology. The three-dimensional structures of TDP-43 domains such as N-terminal domain (NTD), RNA-recognition motif-1 (RRM1), RNA-recognition motif-2 (RRM2) and the C-terminal domain (CTD) or low-complexity domain (LCD) have been solved. These structures have yielded insights into novel binding sites and pockets at various TDP-43 domains, which can be targeted by designing a diverse library of ligands including small molecules, peptides and oligonucleotides as molecular tools to (i) study TDP-43 function, (ii) develop novel diagnostic agents and (iii) discover disease-modifying therapies to treat TDP-43 proteinopathies. This review provides a summary on recent progress in the development of TDP-43 binding ligands and uses the solved structures of various TDP-43 domains to investigate putative ligand binding regions that can be exploited to discover novel molecular probes to modulate TDP-43 structure and function.
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12
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Liu W, Li C, Shan J, Wang Y, Chen G. Insights into the aggregation mechanism of RNA recognition motif domains in TDP-43: a theoretical exploration. ROYAL SOCIETY OPEN SCIENCE 2021; 8:210160. [PMID: 34457335 PMCID: PMC8371369 DOI: 10.1098/rsos.210160] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/04/2021] [Accepted: 07/19/2021] [Indexed: 05/10/2023]
Abstract
The transactive response DNA-binding protein 43 (TDP-43) is associated with several diseases such as amyotrophic lateral sclerosis (ALS) and frontotemporal lobar degeneration (FTLD) due to pathogenic aggregations. In this work, we examined the dimer, tetramer and hexamer models built from the RRM domains of TDP-43 using molecular dynamics simulations in combination with the protein-protein docking. Our results showed that the formations of the dimer models are mainly achieved by the interactions of the RRM1 domains. The parallel β-sheet layers between the RRM1 domains provide most of the binding sites in these oligomer models, and thus play an important role in the aggregation process. The approaching of the parallel β-sheet layers from small oligomer models gradually expand to large ones through the allosteric communication between the α1/α2 helices of the RRM1 domains, which maintains the binding affinities and interactions in the larger oligomer models. Using the repeatable-superimposing method based on the tetramer models, we proposed a new aggregation mechanism of RRM domains in TDP-43, which could well characterize the formation of the large aggregation models with the repeated, helical and rope-like structures. These new insights help to understand the amyloid-like aggregation phenomena of TDP-43 protein in ALS and FTLD diseases.
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Affiliation(s)
- Wei Liu
- Key Laboratory of Theoretical and Computational Photochemistry, Ministry of Education, College of Chemistry, Beijing Normal University, Beijing 100875, People's Republic of China
| | - Chaoqun Li
- Hebei Key Laboratory of Heterocyclic Compounds, College of Chemistry, Chemical Engineering and Materials, Handan University, Handan 056005, Hebei Province, People's Republic of China
| | - Jiankai Shan
- Key Laboratory of Theoretical and Computational Photochemistry, Ministry of Education, College of Chemistry, Beijing Normal University, Beijing 100875, People's Republic of China
| | - Yan Wang
- Key Laboratory of Theoretical and Computational Photochemistry, Ministry of Education, College of Chemistry, Beijing Normal University, Beijing 100875, People's Republic of China
| | - Guangju Chen
- Key Laboratory of Theoretical and Computational Photochemistry, Ministry of Education, College of Chemistry, Beijing Normal University, Beijing 100875, People's Republic of China
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13
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Chhangani D, Martín-Peña A, Rincon-Limas DE. Molecular, functional, and pathological aspects of TDP-43 fragmentation. iScience 2021; 24:102459. [PMID: 34013172 PMCID: PMC8113996 DOI: 10.1016/j.isci.2021.102459] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Transactive response DNA binding protein 43 (TDP-43) is a DNA/RNA binding protein involved in transcriptional regulation and RNA processing. It is linked to sporadic and familial amyotrophic lateral sclerosis and frontotemporal lobar degeneration. TDP-43 is predominantly nuclear, but it translocates to the cytoplasm under pathological conditions. Cytoplasmic accumulation, phosphorylation, ubiquitination and truncation of TDP-43 are the main hallmarks of TDP-43 proteinopathies. Among these processes, the pathways leading to TDP-43 fragmentation remain poorly understood. We review here the molecular and biochemical properties of several TDP-43 fragments, the mechanisms and factors mediating their production, and their potential role in disease progression. We also address the presence of TDP-43 C-terminal fragments in several neurological disorders, including Alzheimer's disease, and highlight their respective implications. Finally, we discuss features of animal models expressing TDP-43 fragments as well as recent therapeutic strategies to approach TDP-43 truncation.
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Affiliation(s)
- Deepak Chhangani
- Department of Neurology, McKnight Brain Institute, and Norman Fixel Institute for Neurological Diseases, University of Florida, Gainesville, FL 32611, USA
| | - Alfonso Martín-Peña
- Department of Neurology, McKnight Brain Institute, and Norman Fixel Institute for Neurological Diseases, University of Florida, Gainesville, FL 32611, USA
| | - Diego E Rincon-Limas
- Department of Neurology, McKnight Brain Institute, and Norman Fixel Institute for Neurological Diseases, University of Florida, Gainesville, FL 32611, USA.,Department of Neuroscience, Center for Translational Research in Neurodegenerative Disease, University of Florida, Gainesville, FL 32611, USA.,Genetics Institute, University of Florida, Gainesville, FL 32611, USA
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14
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Pantoja-Uceda D, Stuani C, Laurents DV, McDermott AE, Buratti E, Mompeán M. NMR assignments for the C-terminal domain of human TDP-43. BIOMOLECULAR NMR ASSIGNMENTS 2021; 15:177-181. [PMID: 33417141 DOI: 10.1007/s12104-020-10002-7] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/04/2020] [Accepted: 12/24/2020] [Indexed: 06/12/2023]
Abstract
Transactive response DNA-binding protein of 43 kDa (TDP-43) is a 414-residue protein whose aberrant aggregation is implicated in neurodegenerative diseases, including amyotrophic lateral sclerosis (ALS) or frontotemporal lobar degeneration (FTLD). Intriguingly, TDP-43 has also been shown to functionally oligomerize to carry out physiological functions. TDP-43 also exists in mixed condensates or granules with other proteins (e.g. neuronal or stress granules), and its large C-terminal domain (CTD, residues 267-414) seems responsible for TDP-43 both homo- and heterotypic interactions underlying such diverse functional and pathological aggregation events. A myriad of distinct triggers may drive TDP-43 oligomerization, including interaction partners or changes in pH or salinity. In this Assignment Note, we report the complete backbone and a wealth of side chain chemical shift assignments for the CTD of TDP-43 at pH 4. The assignments presented here provide a solid starting point to study the aggregation pathway of TDP-43 at pH values below those considered physiological but relevant in pathological settings, and to contrast the aggregation behaviour under distinct conditions and in the presence of interacting partners.
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Affiliation(s)
- David Pantoja-Uceda
- "Rocasolano" Institute for Physical Chemistry, Spanish National Research Council, Serrano 119, 28006, Madrid, Spain
| | - Cristiana Stuani
- International Centre for Genetic Engineering and Biotechnology (ICGEB), Padriciano 99, 34149, Trieste, Italy
| | - Douglas V Laurents
- "Rocasolano" Institute for Physical Chemistry, Spanish National Research Council, Serrano 119, 28006, Madrid, Spain
| | - Ann E McDermott
- Department of Chemistry, Columbia University, New York, NY, 10027, USA
| | - Emanuele Buratti
- International Centre for Genetic Engineering and Biotechnology (ICGEB), Padriciano 99, 34149, Trieste, Italy
| | - Miguel Mompeán
- "Rocasolano" Institute for Physical Chemistry, Spanish National Research Council, Serrano 119, 28006, Madrid, Spain.
- Department of Chemistry, Columbia University, New York, NY, 10027, USA.
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15
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Wells C, Brennan S, Keon M, Ooi L. The role of amyloid oligomers in neurodegenerative pathologies. Int J Biol Macromol 2021; 181:582-604. [PMID: 33766600 DOI: 10.1016/j.ijbiomac.2021.03.113] [Citation(s) in RCA: 42] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2020] [Revised: 02/18/2021] [Accepted: 03/19/2021] [Indexed: 11/25/2022]
Abstract
Many neurodegenerative diseases are rooted in the activities of amyloid-like proteins which possess conformations that spread to healthy proteins. These include Alzheimer's disease (AD), Parkinson's disease (PD), Huntington's disease (HD) and amyotrophic lateral sclerosis (ALS). While their clinical manifestations vary, their protein-level mechanisms are remarkably similar. Aberrant monomeric proteins undergo conformational shifts, facilitating aggregation and formation of solid fibrils. However, there is growing evidence that intermediate oligomeric stages are key drivers of neuronal toxicity. Analysis of protein dynamics is complicated by the fact that nucleation and growth of amyloid-like proteins is not a linear pathway. Feedback within this pathway results in exponential acceleration of aggregation, but activities exerted by oligomers and fibrils can alter cellular interactions and the cellular environment as a whole. The resulting cascade of effects likely contributes to the late onset and accelerating progression of amyloid-like protein disorders and the widespread effects they have on the body. In this review we explore the amyloid-like proteins associated with AD, PD, HD and ALS, as well as the common mechanisms of amyloid-like protein nucleation and aggregation. From this, we identify core elements of pathological progression which have been targeted for therapies, and which may become future therapeutic targets.
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Affiliation(s)
- Cameron Wells
- GenieUs Genomics, Sydney, NSW 2010, Australia; University of New South Wales, Sydney, NSW 2052, Australia
| | | | - Matt Keon
- GenieUs Genomics, Sydney, NSW 2010, Australia
| | - Lezanne Ooi
- Illawarra Health and Medical Research Institute, Wollongong, NSW 2522, Australia; School of Chemistry and Molecular Bioscience, and Molecular Horizons, University of Wollongong, Wollongong, NSW 2522, Australia; GenieUs Genomics, Sydney, NSW 2010, Australia
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16
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Buratti E. Targeting TDP-43 proteinopathy with drugs and drug-like small molecules. Br J Pharmacol 2020; 178:1298-1315. [PMID: 32469420 DOI: 10.1111/bph.15148] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2020] [Revised: 05/19/2020] [Accepted: 05/20/2020] [Indexed: 02/06/2023] Open
Abstract
Following the discovery of the involvement of the ribonucleoprotein TDP-43 in amyotrophic lateral sclerosis (ALS) and frontotemporal lobar degeneration (FTLD), a major research focus has been to develop treatments that can prevent or alleviate these disease conditions. One pharmacological approach has been to use TDP-43-based disease models to test small molecules and drugs already known to have some therapeutic effect in a variety of neurodegenerative conditions. In parallel, various disease models have been used to perform high-throughput screens of drugs and small compound libraries. The aim of this review will be to provide a general overview of the compounds that have been described to alter pathological characteristics of TDP-43. These include expression levels, cytoplasmic mis-localization, post-translational modifications, cleavage, stress granule recruitment and aggregation. In parallel, this review will also address the use of compounds that modify the autophagic/proteasome systems that are known to target TDP-43 misfolding and aggregation. LINKED ARTICLES: This article is part of a themed issue on Neurochemistry in Japan. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v178.6/issuetoc.
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Affiliation(s)
- Emanuele Buratti
- International Centre for Genetic Engineering and Biotechnology (ICGEB), Trieste, Italy
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17
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Weskamp K, Tank EM, Miguez R, McBride JP, Gómez NB, White M, Lin Z, Gonzalez CM, Serio A, Sreedharan J, Barmada SJ. Shortened TDP43 isoforms upregulated by neuronal hyperactivity drive TDP43 pathology in ALS. J Clin Invest 2020; 130:1139-1155. [PMID: 31714900 PMCID: PMC7269575 DOI: 10.1172/jci130988] [Citation(s) in RCA: 72] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2019] [Accepted: 11/06/2019] [Indexed: 12/13/2022] Open
Abstract
Cortical hyperexcitability and mislocalization of the RNA-binding protein TDP43 are highly conserved features in amyotrophic lateral sclerosis (ALS). Nevertheless, the relationship between these phenomena remains poorly defined. Here, we showed that hyperexcitability recapitulates TDP43 pathology by upregulating shortened TDP43 (sTDP43) splice isoforms. These truncated isoforms accumulated in the cytoplasm and formed insoluble inclusions that sequestered full-length TDP43 via preserved N-terminal interactions. Consistent with these findings, sTDP43 overexpression was toxic to mammalian neurons, suggesting neurodegeneration arising from complementary gain- and loss-of-function mechanisms. In humans and mice, sTDP43 transcripts were enriched in vulnerable motor neurons, and we observed a striking accumulation of sTDP43 within neurons and glia of ALS patients. Collectively, these studies uncover a pathogenic role for alternative TDP43 isoforms in ALS, and implicate sTDP43 as a key contributor to the susceptibility of motor neurons in this disorder.
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Affiliation(s)
| | | | | | - Jonathon P. McBride
- Department of Neurology
- Cellular and Molecular Biology Program, Michigan Medicine, University of Michigan, Ann Arbor, Michigan, USA
| | - Nicolás B. Gómez
- Department of Neurology
- Cellular and Molecular Biology Program, Michigan Medicine, University of Michigan, Ann Arbor, Michigan, USA
| | | | - Ziqiang Lin
- Department of Basic and Clinical Neuroscience and
| | - Carmen Moreno Gonzalez
- Centre for Craniofacial and Regenerative Biology, King’s College London, London, United Kingdom
| | - Andrea Serio
- Centre for Craniofacial and Regenerative Biology, King’s College London, London, United Kingdom
| | | | - Sami J. Barmada
- Department of Neurology
- Neuroscience Graduate Program, and
- Cellular and Molecular Biology Program, Michigan Medicine, University of Michigan, Ann Arbor, Michigan, USA
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18
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François-Moutal L, Perez-Miller S, Scott DD, Miranda VG, Mollasalehi N, Khanna M. Structural Insights Into TDP-43 and Effects of Post-translational Modifications. Front Mol Neurosci 2019; 12:301. [PMID: 31920533 PMCID: PMC6934062 DOI: 10.3389/fnmol.2019.00301] [Citation(s) in RCA: 67] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2019] [Accepted: 11/25/2019] [Indexed: 12/12/2022] Open
Abstract
Transactive response DNA binding protein (TDP-43) is a key player in neurodegenerative diseases. In this review, we have gathered and presented structural information on the different regions of TDP-43 with high resolution structures available. A thorough understanding of TDP-43 structure, effect of modifications, aggregation and sites of localization is necessary as we develop therapeutic strategies targeting TDP-43 for neurodegenerative diseases. We discuss how different domains as well as post-translational modification may influence TDP-43 overall structure, aggregation and droplet formation. The primary aim of the review is to utilize structural insights as we develop an understanding of the deleterious behavior of TDP-43 and highlight locations of established and proposed post-translation modifications. TDP-43 structure and effect on localization is paralleled by many RNA-binding proteins and this review serves as an example of how structure may be modulated by numerous compounding elements.
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Affiliation(s)
- Liberty François-Moutal
- Department of Pharmacology, College of Medicine, University of Arizona, Tucson, AZ, United States.,Center for Innovation in Brain Science, Tucson, AZ, United States
| | - Samantha Perez-Miller
- Department of Pharmacology, College of Medicine, University of Arizona, Tucson, AZ, United States.,Center for Innovation in Brain Science, Tucson, AZ, United States
| | - David D Scott
- Department of Pharmacology, College of Medicine, University of Arizona, Tucson, AZ, United States.,Center for Innovation in Brain Science, Tucson, AZ, United States
| | - Victor G Miranda
- Department of Pharmacology, College of Medicine, University of Arizona, Tucson, AZ, United States.,Center for Innovation in Brain Science, Tucson, AZ, United States
| | - Niloufar Mollasalehi
- Department of Pharmacology, College of Medicine, University of Arizona, Tucson, AZ, United States.,Center for Innovation in Brain Science, Tucson, AZ, United States.,Department of Chemistry and Biochemistry, University of Arizona, Tucson, AZ, United States
| | - May Khanna
- Department of Pharmacology, College of Medicine, University of Arizona, Tucson, AZ, United States.,Center for Innovation in Brain Science, Tucson, AZ, United States
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19
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RNA recognition motifs of disease-linked RNA-binding proteins contribute to amyloid formation. Sci Rep 2019; 9:6171. [PMID: 30992467 PMCID: PMC6467989 DOI: 10.1038/s41598-019-42367-8] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2019] [Accepted: 03/26/2019] [Indexed: 12/12/2022] Open
Abstract
Aberrant expression, dysfunction and particularly aggregation of a group of RNA-binding proteins, including TDP-43, FUS and RBM45, are associated with neurological disorders. These three disease-linked RNA-binding proteins all contain at least one RNA recognition motif (RRM). However, it is not clear if these RRMs contribute to their aggregation-prone character. Here, we compare the biophysical and fibril formation properties of five RRMs from disease-linked RNA-binding proteins and five RRMs from non-disease-associated proteins to determine if disease-linked RRMs share specific features making them prone to self-assembly. We found that most of the disease-linked RRMs exhibit reversible thermal unfolding and refolding, and have a slightly lower average thermal melting point compared to that of normal RRMs. The full domain of TDP-43 RRM1 and FUS RRM, as well as the β-peptides from these two RRMs, could self-assemble into fibril-like aggregates which are amyloids of parallel β-sheets as verified by X-ray diffraction and FT-IR spectroscopy. Our results suggest that some disease-linked RRMs indeed play important roles in amyloid formation and shed light on why RNA-binding proteins with RRMs are frequently identified in the cellular inclusions of neurodegenerative diseases.
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20
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Berning BA, Walker AK. The Pathobiology of TDP-43 C-Terminal Fragments in ALS and FTLD. Front Neurosci 2019; 13:335. [PMID: 31031584 PMCID: PMC6470282 DOI: 10.3389/fnins.2019.00335] [Citation(s) in RCA: 106] [Impact Index Per Article: 21.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2019] [Accepted: 03/22/2019] [Indexed: 12/11/2022] Open
Abstract
During neurodegenerative disease, the multifunctional RNA-binding protein TDP-43 undergoes a vast array of post-translational modifications, including phosphorylation, acetylation, and cleavage. Many of these alterations may directly contribute to the pathogenesis of TDP-43 proteinopathies, which include most forms of amyotrophic lateral sclerosis (ALS) and approximately half of all frontotemporal dementia, pathologically identified as frontotemporal lobar degeneration (FTLD) with TDP-43 pathology. However, the relative contributions of the various TDP-43 post-translational modifications to disease remain unclear, and indeed some may be secondary epiphenomena rather than disease-causative. It is therefore critical to determine the involvement of each modification in disease processes to allow the design of targeted treatments. In particular, TDP-43 C-terminal fragments (CTFs) accumulate in the brains of people with ALS and FTLD and are therefore described as a neuropathological signature of these diseases. Remarkably, these TDP-43 CTFs are rarely observed in the spinal cord, even in ALS which involves dramatic degeneration of spinal motor neurons. Therefore, TDP-43 CTFs are not produced non-specifically in the course of all forms of TDP-43-related neurodegeneration, but rather variably arise due to additional factors influenced by regional heterogeneity in the central nervous system. In this review, we summarize how TDP-43 CTFs are generated and degraded by cells, and critique evidence from studies of TDP-43 CTF pathology in human disease tissues, as well as cell and animal models, to analyze the pathophysiological relevance of TDP-43 CTFs to ALS and FTLD. Numerous studies now indicate that, although TDP-43 CTFs are prevalent in ALS and FTLD brains, disease-related pathology is only variably reproduced in TDP-43 CTF cell culture models. Furthermore, TDP-43 CTF expression in both transgenic and viral-mediated in vivo models largely fails to induce motor or behavioral dysfunction reminiscent of human disease. We therefore conclude that although TDP-43 CTFs are a hallmark of TDP-43-related neurodegeneration in the brain, they are not a primary cause of ALS or FTLD.
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Affiliation(s)
- Britt A. Berning
- Neurodegeneration Pathobiology Laboratory, Queensland Brain Institute, University of Queensland, Brisbane, QLD, Australia
| | - Adam K. Walker
- Neurodegeneration Pathobiology Laboratory, Queensland Brain Institute, University of Queensland, Brisbane, QLD, Australia
- Centre for Motor Neuron Disease Research, Department of Biomedical Sciences, Faculty of Medicine and Health Sciences, Macquarie University, North Ryde, NSW, Australia
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21
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Iglesias V, Paladin L, Juan-Blanco T, Pallarès I, Aloy P, Tosatto SCE, Ventura S. In silico Characterization of Human Prion-Like Proteins: Beyond Neurological Diseases. Front Physiol 2019; 10:314. [PMID: 30971948 PMCID: PMC6445884 DOI: 10.3389/fphys.2019.00314] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2018] [Accepted: 03/07/2019] [Indexed: 12/18/2022] Open
Abstract
Prion-like behavior has been in the spotlight since it was first associated with the onset of mammalian neurodegenerative diseases. However, a growing body of evidence suggests that this mechanism could be behind the regulation of processes such as transcription and translation in multiple species. Here, we perform a stringent computational survey to identify prion-like proteins in the human proteome. We detected 242 candidate polypeptides and computationally assessed their function, protein–protein interaction networks, tissular expression, and their link to disease. Human prion-like proteins constitute a subset of modular polypeptides broadly expressed across different cell types and tissues, significantly associated with disease, embedded in highly connected interaction networks, and involved in the flow of genetic information in the cell. Our analysis suggests that these proteins might play a relevant role not only in neurological disorders, but also in different types of cancer and viral infections.
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Affiliation(s)
- Valentin Iglesias
- Institut de Biotecnologia i de Biomedicina, Departament de Bioquímica i Biologia Molecular, Universitat Autònoma de Barcelona, Barcelona, Spain
| | - Lisanna Paladin
- Department of Biomedical Sciences, University of Padua, Padua, Italy
| | - Teresa Juan-Blanco
- Joint IRB-BSC-CRG Program in Computational Biology, Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology, Barcelona, Spain
| | - Irantzu Pallarès
- Institut de Biotecnologia i de Biomedicina, Departament de Bioquímica i Biologia Molecular, Universitat Autònoma de Barcelona, Barcelona, Spain
| | - Patrick Aloy
- Joint IRB-BSC-CRG Program in Computational Biology, Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology, Barcelona, Spain.,Institució Catalana de Recerca i Estudis Avançats, Barcelona, Spain
| | - Silvio C E Tosatto
- Department of Biomedical Sciences, University of Padua, Padua, Italy.,CNR Institute of Neuroscience, Padua, Italy
| | - Salvador Ventura
- Institut de Biotecnologia i de Biomedicina, Departament de Bioquímica i Biologia Molecular, Universitat Autònoma de Barcelona, Barcelona, Spain
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22
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Sun Y, Medina Cruz A, Hadley KC, Galant NJ, Law R, Vernon RM, Morris VK, Robertson J, Chakrabartty A. Physiologically Important Electrolytes as Regulators of TDP-43 Aggregation and Droplet-Phase Behavior. Biochemistry 2018; 58:590-607. [DOI: 10.1021/acs.biochem.8b00842] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Affiliation(s)
- Yulong Sun
- University Health Network, Princess Margaret Cancer Centre, University of Toronto, TMDT 4-305, 101 College Street, Toronto, ON M5G 1L7, Canada
| | - Alison Medina Cruz
- Department of Medical Biophysics, Princess Margaret Cancer Centre, University of Toronto, TMDT 4-305, 101 College Street, Toronto, ON M5G 1L7, Canada
| | - Kevin C. Hadley
- University Health Network, Princess Margaret Cancer Centre, University of Toronto, TMDT 4-305, 101 College Street, Toronto, ON M5G 1L7, Canada
| | - Natalie J. Galant
- University Health Network, Princess Margaret Cancer Centre, University of Toronto, TMDT 4-305, 101 College Street, Toronto, ON M5G 1L7, Canada
| | - Ryan Law
- Department of Medical Biophysics, Princess Margaret Cancer Centre, University of Toronto, TMDT 4-305, 101 College Street, Toronto, ON M5G 1L7, Canada
| | - Robert M. Vernon
- Program in Molecular Medicine, The Hospital for Sick Children, Toronto, ON M5G 0A4, Canada
| | - Vanessa K. Morris
- University Health Network, Princess Margaret Cancer Centre, University of Toronto, TMDT 4-305, 101 College Street, Toronto, ON M5G 1L7, Canada
- School of Biological Sciences, University of Canterbury, Ilam, Christchurch 8041, New Zealand
| | - Janice Robertson
- Tanz Centre for Research in Neurodegenerative Diseases, University of Toronto, Toronto, ON M5T 2S8, Canada
| | - Avijit Chakrabartty
- University Health Network, Princess Margaret Cancer Centre, University of Toronto, TMDT 4-305, 101 College Street, Toronto, ON M5G 1L7, Canada
- Department of Medical Biophysics, Princess Margaret Cancer Centre, University of Toronto, TMDT 4-305, 101 College Street, Toronto, ON M5G 1L7, Canada
- Department of Biochemistry, University of Toronto, TMDT 4-305, 101 College Street, Toronto, ON M5G 1L7, Canada
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23
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Lee YC, Huang WC, Lin JH, Kao TJ, Lin HC, Lee KH, Lin HC, Shen CKJ, Chang WC, Huang CC. Znf179 E3 ligase-mediated TDP-43 polyubiquitination is involved in TDP-43- ubiquitinated inclusions (UBI) (+)-related neurodegenerative pathology. J Biomed Sci 2018; 25:76. [PMID: 30404641 PMCID: PMC6223059 DOI: 10.1186/s12929-018-0479-4] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2018] [Accepted: 10/24/2018] [Indexed: 12/13/2022] Open
Abstract
Background The brain predominantly expressed RING finger protein, Znf179, is known to be important for embryonic neuronal differentiation during brain development. Downregulation of Znf179 has been observed in motor neurons of adult mouse models for amyotrophic lateral sclerosis (ALS), yet the molecular function of Znf179 in neurodegeneration has never been previously described. Znf179 contains the classical C3HC4 RING finger domain, and numerous proteins containing C3HC4 RING finger domain act as E3 ubiquitin ligases. Hence, we are interested to identify whether Znf179 possesses E3 ligase activity and its role in ALS neuropathy. Methods We used in vivo and in vitro ubiquitination assay to examine the E3 ligase autoubiquitination activity of Znf179 and its effect on 26S proteasome activity. To search for the candidate substrates of Znf179, we immunoprecipitated Znf179 and subjected to mass spectrometry (MS) analysis to identify its interacting proteins. We found that ALS/ FTLD-U (frontotemporal lobar degeneration (FTLD) with ubiquitin inclusions)-related neurodegenerative TDP-43 protein is the E3 ligase substrate of Znf179. To further clarify the role of E3 ubiquitin ligase Znf179 in neurodegenerative TDP-43-UBI (ubiquitinated inclusions) (+) proteinopathy, the effect of Znf179-mediated TDP-43 polyubiquitination on TDP-43 protein stability, aggregate formation and nucleus/cytoplasm mislocalization were evaluated in vitro cell culture system and in vivo animal model. Results Here we report that Znf179 is a RING E3 ubiquitin ligase which possesses autoubiquitination feature and regulates 26S proteasome activity through modulating the protein expression levels of 19S/20S proteasome subunits. Our immunoprecipitation assay and MS analysis results revealed that the neuropathological TDP-43 protein is one of its E3 ligase substrate. Znf179 interactes with TDP-43 protein and mediates polyubiquitination of TDP-43 in vitro and in vivo. In neurodegenerative TDP-43 proteinopathy, we found that Znf179-mediated polyubiquitination of TDP-43 accelerates its protein turnover rate and attenuates insoluble pathologic TDP-43 aggregates, while knockout of Znf179 in mouse brain results in accumulation of insoluble TDP-43 and cytosolic TDP-43 inclusions in cortex, hippocampus and midbrain regions. Conclusions Here we unveil the important role for the novel E3 ligase Znf179 in TDP-43-mediated neuropathy, and provide a potential therapeutic strategy for combating ALS/ FTLD-U neurodegenerative pathologies. Electronic supplementary material The online version of this article (10.1186/s12929-018-0479-4) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Yi-Chao Lee
- Graduate Institute of Neural Regenerative Medicine, College of Medical Science and Technology/Center for Neurotrauma and Neuroregeneration, Taipei Medical University, Taipei, 115, Taiwan
| | - Wan-Chen Huang
- Institute of Cellular and Organismic Biology, Academia Sinica, Taipei, 115, Taiwan
| | - Jiann-Her Lin
- Graduate Institute of Neural Regenerative Medicine, College of Medical Science and Technology/Center for Neurotrauma and Neuroregeneration, Taipei Medical University, Taipei, 115, Taiwan.,Department of Neurosurgery, Taipei Medical University, Taipei, Taiwan.,Division of Neurosurgery, Department of Surgery, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan
| | - Tzu-Jen Kao
- Graduate Institute of Neural Regenerative Medicine, College of Medical Science and Technology/Center for Neurotrauma and Neuroregeneration, Taipei Medical University, Taipei, 115, Taiwan
| | - Hui-Ching Lin
- Institute and Department of Physiology, School of Medicine, National Yang-Ming University, Taipei, 112, Taiwan
| | - Kuen-Haur Lee
- Graduate Institute of Cancer Biology and Drug Discovery, College of Medical Science and Technology, Taipei Medical University, Taipei, 115, Taiwan
| | - Hsin-Chuan Lin
- Graduate Institute of Medical Sciences, College of Medicine, Taipei Medical University, Taipei, 110, Taiwan
| | | | - Wen-Chang Chang
- Graduate Institute of Medical Sciences, College of Medicine, Taipei Medical University, Taipei, 110, Taiwan
| | - Chi-Chen Huang
- Graduate Institute of Neural Regenerative Medicine, College of Medical Science and Technology/Center for Neurotrauma and Neuroregeneration, Taipei Medical University, Taipei, 115, Taiwan.
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24
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Senataxin mutations elicit motor neuron degeneration phenotypes and yield TDP-43 mislocalization in ALS4 mice and human patients. Acta Neuropathol 2018; 136:425-443. [PMID: 29725819 DOI: 10.1007/s00401-018-1852-9] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2017] [Revised: 04/23/2018] [Accepted: 04/23/2018] [Indexed: 12/12/2022]
Abstract
Amyotrophic lateral sclerosis type 4 (ALS4) is a rare, early-onset, autosomal dominant form of ALS, characterized by slow disease progression and sparing of respiratory musculature. Dominant, gain-of-function mutations in the senataxin gene (SETX) cause ALS4, but the mechanistic basis for motor neuron toxicity is unknown. SETX is a RNA-binding protein with a highly conserved helicase domain, but does not possess a low-complexity domain, making it unique among ALS-linked disease proteins. We derived ALS4 mouse models by expressing two different senataxin gene mutations (R2136H and L389S) via transgenesis and knock-in gene targeting. Both approaches yielded SETX mutant mice that develop neuromuscular phenotypes and motor neuron degeneration. Neuropathological characterization of SETX mice revealed nuclear clearing of TDP-43, accompanied by TDP-43 cytosolic mislocalization, consistent with the hallmark pathology observed in human ALS patients. Postmortem material from ALS4 patients exhibited TDP-43 mislocalization in spinal cord motor neurons, and motor neurons from SETX ALS4 mice displayed enhanced stress granule formation. Immunostaining analysis for nucleocytoplasmic transport proteins Ran and RanGAP1 uncovered nuclear membrane abnormalities in the motor neurons of SETX ALS4 mice, and nuclear import was delayed in SETX ALS4 cortical neurons, indicative of impaired nucleocytoplasmic trafficking. SETX ALS4 mice thus recapitulated ALS disease phenotypes in association with TDP-43 mislocalization and provided insight into the basis for TDP-43 histopathology, linking SETX dysfunction to common pathways of ALS motor neuron degeneration.
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25
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Bishof I, Dammer EB, Duong DM, Kundinger SR, Gearing M, Lah JJ, Levey AI, Seyfried NT. RNA-binding proteins with basic-acidic dipeptide (BAD) domains self-assemble and aggregate in Alzheimer's disease. J Biol Chem 2018; 293:11047-11066. [PMID: 29802200 PMCID: PMC6052236 DOI: 10.1074/jbc.ra118.001747] [Citation(s) in RCA: 50] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2018] [Revised: 05/23/2018] [Indexed: 12/12/2022] Open
Abstract
The U1 small nuclear ribonucleoprotein 70 kDa (U1-70K) and other RNA-binding proteins (RBPs) are mislocalized to cytoplasmic neurofibrillary Tau aggregates in Alzheimer's disease (AD), yet the co-aggregation mechanisms are incompletely understood. U1-70K harbors two disordered low-complexity domains (LC1 and LC2) that are necessary for aggregation in AD brain extracts. The LC1 domain contains highly repetitive basic (Arg/Lys) and acidic (Asp/Glu) residues, referred to as a basic-acidic dipeptide (BAD) domain. We report here that this domain shares many of the properties of the Gln/Asn-rich LC domains in RBPs that also aggregate in neurodegenerative disease. These properties included self-assembly into oligomers and localization to nuclear granules. Co-immunoprecipitations of recombinant U1-70K and deletions lacking the LC domain(s) followed by quantitative proteomic analyses were used to resolve functional classes of U1-70K-interacting proteins that depend on the BAD domain for their interaction. Within this interaction network, we identified a class of RBPs with BAD domains nearly identical to that found in U1-70K. Two members of this class, LUC7L3 and RBM25, required their respective BAD domains for reciprocal interactions with U1-70K and nuclear granule localization. Strikingly, a significant proportion of RBPs with BAD domains had elevated insolubility in the AD brain proteome. Furthermore, we show that the BAD domain of U1-70K can interact with Tau from AD brains but not from other tauopathies. These findings highlight a mechanistic role for BAD domains in stabilizing RBP interactions and in potentially mediating co-aggregation with the pathological AD-specific Tau isoforms.
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Affiliation(s)
- Isaac Bishof
- From the Departments of Biochemistry
- the Center for Neurodegenerative Diseases, Emory University School of Medicine, Atlanta, Georgia 30322
| | - Eric B Dammer
- From the Departments of Biochemistry
- the Center for Neurodegenerative Diseases, Emory University School of Medicine, Atlanta, Georgia 30322
| | - Duc M Duong
- From the Departments of Biochemistry
- the Center for Neurodegenerative Diseases, Emory University School of Medicine, Atlanta, Georgia 30322
| | - Sean R Kundinger
- From the Departments of Biochemistry
- the Center for Neurodegenerative Diseases, Emory University School of Medicine, Atlanta, Georgia 30322
| | - Marla Gearing
- the Center for Neurodegenerative Diseases, Emory University School of Medicine, Atlanta, Georgia 30322
- Pathology and Laboratory Medicine and
| | - James J Lah
- the Center for Neurodegenerative Diseases, Emory University School of Medicine, Atlanta, Georgia 30322
- Neurology, and
| | - Allan I Levey
- the Center for Neurodegenerative Diseases, Emory University School of Medicine, Atlanta, Georgia 30322
- Neurology, and
| | - Nicholas T Seyfried
- From the Departments of Biochemistry,
- the Center for Neurodegenerative Diseases, Emory University School of Medicine, Atlanta, Georgia 30322
- Neurology, and
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26
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Prasad A, Sivalingam V, Bharathi V, Girdhar A, Patel BK. The amyloidogenicity of a C-terminal region of TDP-43 implicated in Amyotrophic Lateral Sclerosis can be affected by anions, acetylation and homodimerization. Biochimie 2018; 150:76-87. [PMID: 29751083 DOI: 10.1016/j.biochi.2018.05.003] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2017] [Accepted: 05/04/2018] [Indexed: 12/11/2022]
Abstract
Amyotrophic Lateral Sclerosis (ALS) is a fatal neurodegenerative disease associated with accumulation of hyper-phosphorylated, and ubiquitinated TAR DNA-binding protein-43 (TDP-43) as inclusion deposits in neuronal cells. Recently, amyloid-like fibrillar aggregates of TDP-43 have been reported from several ALS patients. The C-terminal region of TDP-43 is central to TDP-43's pathological aggregation and most of the familial ALS mutations in the encoding TARDBP gene are located in this domain. Also, aberrant proteolytic cleavages of TDP-43 produce cytotoxic C-terminal fragments of ∼15-35 kDa. The C-terminal end harbours a glycine-rich region and a Q/N rich prion-like aggregation-prone domain which has been shown to form amyloid-like fibrillar aggregates in vitro. Previously, TDP-43 protein has also been shown to undergo several other post-translational modifications such as acetylation and dimerization, however, their effects on TDP-43's amyloid-like in vitro aggregation have not been examined. Towards this, we have here examined effects of anions, acetylation and homodimerization on the in vitro aggregation of a C-terminal fragment (amino acid: 193-414) of TDP-43 termed TDP-432C. We find that kosmotropic anions greatly accelerate whereas chaotropic anions impede its aggregation. Also, we show that acetylation of certain lysines in C-terminal fragments significantly reduces the TDP-432C's amyloid-like aggregation. Furthermore, we separated spontaneously formed cysteine-linked homodimers of the recombinantly purified TDP-432C using size-exclusion chromatography and found that these dimers retain amyloidogenicity. These findings would be of significance to the TDP-43 aggregation-induced pathology in ALS.
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Affiliation(s)
- Archana Prasad
- Department of Biotechnology, Indian Institute of Technology Hyderabad, Kandi, Sangareddy, Telangana, 502285, India
| | - Vishwanath Sivalingam
- Department of Biotechnology, Indian Institute of Technology Hyderabad, Kandi, Sangareddy, Telangana, 502285, India
| | - Vidhya Bharathi
- Department of Biotechnology, Indian Institute of Technology Hyderabad, Kandi, Sangareddy, Telangana, 502285, India
| | - Amandeep Girdhar
- Department of Biotechnology, Indian Institute of Technology Hyderabad, Kandi, Sangareddy, Telangana, 502285, India
| | - Basant K Patel
- Department of Biotechnology, Indian Institute of Technology Hyderabad, Kandi, Sangareddy, Telangana, 502285, India.
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27
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Oberstadt M, Stieler J, Simpong DL, Römuß U, Urban N, Schaefer M, Arendt T, Holzer M. TDP-43 self-interaction is modulated by redox-active compounds Auranofin, Chelerythrine and Riluzole. Sci Rep 2018; 8:2248. [PMID: 29396541 PMCID: PMC5797228 DOI: 10.1038/s41598-018-20565-0] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2017] [Accepted: 01/19/2018] [Indexed: 12/11/2022] Open
Abstract
Amyotrophic lateral sclerosis (ALS) represents a fatal neurodegenerative disease, which is characterized by a rapid loss of lower and upper motor neurons. As a major neuropathological hallmark, protein aggregates containing the Transactivating Response Region (TAR) DNA Binding Protein (TDP-43) are detectable in about 95% of sporadic ALS patients. TDP-43 interacts with itself physiologically to form liquid droplets, which may progress to pathological aggregates. In this study, we established the NanoBit luciferase complementation assay to measure TDP-43 self-interaction and found the fusion of the split luciferase subunits to the N-terminus of the protein as the strongest interacting partners. A screen of pharmacologically active compounds from the LOPAC®1280 library identified auranofin, chelerythrine and riluzole as dose-dependent inhibitors of TDP-43 self-interaction. Further analysis of drug action of the gold-containing thioredoxin reductase inhibitor auranofin revealed a redistribution from insoluble TDP-43 protein pool to PBS-soluble protein pool in N2a cells. In addition, auranofin treatment diminished reduced glutathione as a sign for oxidative modulation.
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Affiliation(s)
- Moritz Oberstadt
- Department of Neurology, University of Leipzig, Liebigstraße 20, 04103, Leipzig, Germany.
| | - Jens Stieler
- Department for Molecular and Cellular Mechanisms of Neurodegeneration, Paul Flechsig Institute for Brain Research, University of Leipzig, Liebigstraße 19, 04103, Leipzig, Germany
| | - David Larbi Simpong
- Department for Molecular and Cellular Mechanisms of Neurodegeneration, Paul Flechsig Institute for Brain Research, University of Leipzig, Liebigstraße 19, 04103, Leipzig, Germany
| | - Ute Römuß
- Department of Neurology, University of Leipzig, Liebigstraße 20, 04103, Leipzig, Germany
| | - Nicole Urban
- Rudolf-Boehm-Institute of Pharmacology and Toxicology, University of Leipzig, Härtelstraße 16-18, 04107, Leipzig, Germany
| | - Michael Schaefer
- Rudolf-Boehm-Institute of Pharmacology and Toxicology, University of Leipzig, Härtelstraße 16-18, 04107, Leipzig, Germany
| | - Thomas Arendt
- Department for Molecular and Cellular Mechanisms of Neurodegeneration, Paul Flechsig Institute for Brain Research, University of Leipzig, Liebigstraße 19, 04103, Leipzig, Germany
| | - Max Holzer
- Department for Molecular and Cellular Mechanisms of Neurodegeneration, Paul Flechsig Institute for Brain Research, University of Leipzig, Liebigstraße 19, 04103, Leipzig, Germany
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28
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Abstract
Mutations in the profilin 1 (PFN1) gene have been identified as a cause of familial amyotrophic lateral sclerosis (ALS), and neuropathological studies indicate that TDP-43 is accumulated in brains of patients with PFN1 mutation. Here, we investigated the role of PFN1 mutations in the formation of prion-like abnormal TDP-43. Expression of PFN1 with pathogenic mutations resulted in the formation of cytoplasmic aggregates positive for p62 and ubiquitin, and these aggregates sequestered endogenous TDP-43. TDP-43 accumulation was facilitated in the presence of proteasome or lysosome inhibitor. Co-expression of mutant PFN1 and TDP-43 increased the levels of detergent-insoluble and phosphorylated TDP-43, and this increase required the C-terminal region of TDP-43. Moreover, detergent-insoluble fractions prepared from cells expressing ALS-linked mutant PFN1 induced seed-dependent accumulation of TDP-43. These findings indicate that expression of PFN1 mutants induces accumulation of TDP-43, and promotes conversion of normal TDP-43 into an abnormal form. These results provide new insight into the mechanisms of TDP-43 proteinopathies and other diseases associated with amyloid-like protein deposition.
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Affiliation(s)
- Yoshinori Tanaka
- a Dementia Research Project, Tokyo Metropolitan Institute of Medical Science , Tokyo , Japan
| | - Masato Hasegawa
- a Dementia Research Project, Tokyo Metropolitan Institute of Medical Science , Tokyo , Japan
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29
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Tsoi PS, Choi K, Leonard PG, Sizovs A, Moosa MM, MacKenzie KR, Ferreon JC, Ferreon ACM. The N‐Terminal Domain of ALS‐Linked TDP‐43 Assembles without Misfolding. Angew Chem Int Ed Engl 2017. [DOI: 10.1002/ange.201706769] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Phoebe S. Tsoi
- Department of Pharmacology and Chemical Biology Baylor College of Medicine Houston TX USA
| | - Kyoung‐Jae Choi
- Department of Pharmacology and Chemical Biology Baylor College of Medicine Houston TX USA
| | - Paul G. Leonard
- Department of Genomic Medicine and Core for Biomolecular Structure and Function University of Texas MD Anderson Cancer Center Houston TX USA
| | - Antons Sizovs
- Department of Pharmacology and Chemical Biology Baylor College of Medicine Houston TX USA
| | - Mahdi Muhammad Moosa
- Department of Pharmacology and Chemical Biology Baylor College of Medicine Houston TX USA
| | - Kevin R. MacKenzie
- Department of Pharmacology and Chemical Biology Baylor College of Medicine Houston TX USA
- Department of Pathology and Immunology Baylor College of Medicine Houston TX USA
| | - Josephine C. Ferreon
- Department of Pharmacology and Chemical Biology Baylor College of Medicine Houston TX USA
| | - Allan Chris M. Ferreon
- Department of Pharmacology and Chemical Biology Baylor College of Medicine Houston TX USA
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30
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Tsoi PS, Choi KJ, Leonard PG, Sizovs A, Moosa MM, MacKenzie KR, Ferreon JC, Ferreon ACM. The N-Terminal Domain of ALS-Linked TDP-43 Assembles without Misfolding. Angew Chem Int Ed Engl 2017; 56:12590-12593. [PMID: 28833982 DOI: 10.1002/anie.201706769] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2017] [Revised: 08/08/2017] [Indexed: 12/28/2022]
Abstract
Transactivation response element (TAR) DNA-binding protein 43 (TDP-43) misfolding is implicated in several neurodegenerative diseases characterized by aggregated protein inclusions. Misfolding is believed to be mediated by both the N- and C-terminus of TDP-43; however, the mechanistic basis of the contribution of individual domains in the process remained elusive. Here, using single-molecule fluorescence and ensemble biophysical techniques, and a wide range of pH and temperature conditions, we show that TDP-43NTD is thermodynamically stable, well-folded and undergoes reversible oligomerization. We propose that, in full-length TDP-43, association between folded N-terminal domains enhances the propensity of the intrinsically unfolded C-terminal domains to drive pathological aggregation.
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Affiliation(s)
- Phoebe S Tsoi
- Department of Pharmacology and Chemical Biology, Baylor College of Medicine, Houston, TX, USA
| | - Kyoung-Jae Choi
- Department of Pharmacology and Chemical Biology, Baylor College of Medicine, Houston, TX, USA
| | - Paul G Leonard
- Department of Genomic Medicine and Core for Biomolecular Structure and Function, University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Antons Sizovs
- Department of Pharmacology and Chemical Biology, Baylor College of Medicine, Houston, TX, USA
| | - Mahdi Muhammad Moosa
- Department of Pharmacology and Chemical Biology, Baylor College of Medicine, Houston, TX, USA
| | - Kevin R MacKenzie
- Department of Pharmacology and Chemical Biology, Baylor College of Medicine, Houston, TX, USA.,Department of Pathology and Immunology, Baylor College of Medicine, Houston, TX, USA
| | - Josephine C Ferreon
- Department of Pharmacology and Chemical Biology, Baylor College of Medicine, Houston, TX, USA
| | - Allan Chris M Ferreon
- Department of Pharmacology and Chemical Biology, Baylor College of Medicine, Houston, TX, USA
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31
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Biology and Pathobiology of TDP-43 and Emergent Therapeutic Strategies. Cold Spring Harb Perspect Med 2017; 7:cshperspect.a024554. [PMID: 27920024 DOI: 10.1101/cshperspect.a024554] [Citation(s) in RCA: 46] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Cytoplasmic TDP-43 mislocalization and aggregation is a pathological hallmark of amyotrophic lateral sclerosis and frontotemporal lobar degeneration. TDP-43 is an RNA-binding protein (RBP) with a prion-like domain (PrLD) that promotes TDP-43 misfolding. PrLDs possess compositional similarity to canonical prion domains of various yeast proteins, including Sup35. Strikingly, disease-causing TDP-43 mutations reside almost exclusively in the PrLD and can enhance TDP-43 misfolding and toxicity. Another ∼70 human RBPs harbor PrLDs, including FUS, TAF15, EWSR1, hnRNPA1, and hnRNPA2, which have surfaced in the etiology of neurodegenerative diseases. Importantly, PrLDs enable RBP function and mediate phase transitions that partition functional ribonucleoprotein compartments. This PrLD activity, however, renders RBPs prone to populating deleterious oligomers or self-templating fibrils that might spread disease, and disease-linked PrLD mutations can exacerbate this risk. Several strategies have emerged to counter TDP-43 proteinopathies, including engineering enhanced protein disaggregases based on Hsp104.
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32
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Ishiguro T, Sato N, Ueyama M, Fujikake N, Sellier C, Kanegami A, Tokuda E, Zamiri B, Gall-Duncan T, Mirceta M, Furukawa Y, Yokota T, Wada K, Taylor JP, Pearson CE, Charlet-Berguerand N, Mizusawa H, Nagai Y, Ishikawa K. Regulatory Role of RNA Chaperone TDP-43 for RNA Misfolding and Repeat-Associated Translation in SCA31. Neuron 2017; 94:108-124.e7. [PMID: 28343865 PMCID: PMC5681996 DOI: 10.1016/j.neuron.2017.02.046] [Citation(s) in RCA: 90] [Impact Index Per Article: 12.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2015] [Revised: 10/04/2016] [Accepted: 02/24/2017] [Indexed: 12/20/2022]
Abstract
Microsatellite expansion disorders are pathologically characterized by RNA foci formation and repeat-associated non-AUG (RAN) translation. However, their underlying pathomechanisms and regulation of RAN translation remain unknown. We report that expression of expanded UGGAA (UGGAAexp) repeats, responsible for spinocerebellar ataxia type 31 (SCA31) in Drosophila, causes neurodegeneration accompanied by accumulation of UGGAAexp RNA foci and translation of repeat-associated pentapeptide repeat (PPR) proteins, consistent with observations in SCA31 patient brains. We revealed that motor-neuron disease (MND)-linked RNA-binding proteins (RBPs), TDP-43, FUS, and hnRNPA2B1, bind to and induce structural alteration of UGGAAexp. These RBPs suppress UGGAAexp-mediated toxicity in Drosophila by functioning as RNA chaperones for proper UGGAAexp folding and regulation of PPR translation. Furthermore, nontoxic short UGGAA repeat RNA suppressed mutated RBP aggregation and toxicity in MND Drosophila models. Thus, functional crosstalk of the RNA/RBP network regulates their own quality and balance, suggesting convergence of pathomechanisms in microsatellite expansion disorders and RBP proteinopathies.
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Affiliation(s)
- Taro Ishiguro
- Department of Neurology and Neurological Science, Graduate School, Tokyo Medical and Dental University (TMDU), Yushima 1-5-45, Bunkyo-ku, Tokyo 113-8519, Japan; Center for Brain Integration Research (CBIR), Tokyo Medical and Dental University (TMDU), Yushima 1-5-45, Bunkyo-ku, Tokyo 113-8519, Japan; Department of Degenerative Neurological Diseases, National Institute of Neuroscience, National Center of Neurology and Psychiatry, 4-1-1 Ogawa-Higashi, Kodaira, Tokyo 187-8502, Japan
| | - Nozomu Sato
- Department of Neurology and Neurological Science, Graduate School, Tokyo Medical and Dental University (TMDU), Yushima 1-5-45, Bunkyo-ku, Tokyo 113-8519, Japan; Center for Brain Integration Research (CBIR), Tokyo Medical and Dental University (TMDU), Yushima 1-5-45, Bunkyo-ku, Tokyo 113-8519, Japan
| | - Morio Ueyama
- Department of Degenerative Neurological Diseases, National Institute of Neuroscience, National Center of Neurology and Psychiatry, 4-1-1 Ogawa-Higashi, Kodaira, Tokyo 187-8502, Japan; Department of Neurotherapeutics, Osaka University Graduate School of Medicine, 2-2 Yamadaoka, Suita, Osaka 565-0871, Japan
| | - Nobuhiro Fujikake
- Department of Degenerative Neurological Diseases, National Institute of Neuroscience, National Center of Neurology and Psychiatry, 4-1-1 Ogawa-Higashi, Kodaira, Tokyo 187-8502, Japan
| | - Chantal Sellier
- Institut de Génétique et de Biologie Moléculaire et Cellulaire, University of Strasbourg, Illkirch 67400, France
| | - Akemi Kanegami
- Research Institute of Biomolecule Metrology, 807-133 Enokido, Tsukuba, Ibaraki 305-0853, Japan
| | - Eiichi Tokuda
- Department of Chemistry, Keio University, 3-14-1 Hiyoshi, Yokohama, Kanagawa 223-8522, Japan
| | - Bita Zamiri
- Department of Pharmaceutical Sciences, Leslie Dan Faculty of Pharmacy, University of Toronto, Toronto, ON M5S 3M2, Canada; Department of Genetics, The Hospital for Sick Children, Peter Gilgan Centre for Research and Learning, 686 Bay Street, Toronto, ON M5G 0A4, Canada
| | - Terence Gall-Duncan
- Department of Genetics, The Hospital for Sick Children, Peter Gilgan Centre for Research and Learning, 686 Bay Street, Toronto, ON M5G 0A4, Canada; Program of Molecular Genetics, University of Toronto, Toronto, ON M5G 0A4, Canada
| | - Mila Mirceta
- Department of Genetics, The Hospital for Sick Children, Peter Gilgan Centre for Research and Learning, 686 Bay Street, Toronto, ON M5G 0A4, Canada; Program of Molecular Genetics, University of Toronto, Toronto, ON M5G 0A4, Canada
| | - Yoshiaki Furukawa
- Department of Chemistry, Keio University, 3-14-1 Hiyoshi, Yokohama, Kanagawa 223-8522, Japan
| | - Takanori Yokota
- Department of Neurology and Neurological Science, Graduate School, Tokyo Medical and Dental University (TMDU), Yushima 1-5-45, Bunkyo-ku, Tokyo 113-8519, Japan; Center for Brain Integration Research (CBIR), Tokyo Medical and Dental University (TMDU), Yushima 1-5-45, Bunkyo-ku, Tokyo 113-8519, Japan
| | - Keiji Wada
- Department of Degenerative Neurological Diseases, National Institute of Neuroscience, National Center of Neurology and Psychiatry, 4-1-1 Ogawa-Higashi, Kodaira, Tokyo 187-8502, Japan
| | - J Paul Taylor
- Department of Developmental Neurobiology, St. Jude Children's Research Hospital, Memphis, TN 38105, USA
| | - Christopher E Pearson
- Department of Genetics, The Hospital for Sick Children, Peter Gilgan Centre for Research and Learning, 686 Bay Street, Toronto, ON M5G 0A4, Canada; Program of Molecular Genetics, University of Toronto, Toronto, ON M5G 0A4, Canada
| | - Nicolas Charlet-Berguerand
- Institut de Génétique et de Biologie Moléculaire et Cellulaire, University of Strasbourg, Illkirch 67400, France
| | - Hidehiro Mizusawa
- Department of Neurology and Neurological Science, Graduate School, Tokyo Medical and Dental University (TMDU), Yushima 1-5-45, Bunkyo-ku, Tokyo 113-8519, Japan; Center for Brain Integration Research (CBIR), Tokyo Medical and Dental University (TMDU), Yushima 1-5-45, Bunkyo-ku, Tokyo 113-8519, Japan
| | - Yoshitaka Nagai
- Department of Degenerative Neurological Diseases, National Institute of Neuroscience, National Center of Neurology and Psychiatry, 4-1-1 Ogawa-Higashi, Kodaira, Tokyo 187-8502, Japan; Department of Neurotherapeutics, Osaka University Graduate School of Medicine, 2-2 Yamadaoka, Suita, Osaka 565-0871, Japan.
| | - Kinya Ishikawa
- Department of Neurology and Neurological Science, Graduate School, Tokyo Medical and Dental University (TMDU), Yushima 1-5-45, Bunkyo-ku, Tokyo 113-8519, Japan; Center for Brain Integration Research (CBIR), Tokyo Medical and Dental University (TMDU), Yushima 1-5-45, Bunkyo-ku, Tokyo 113-8519, Japan; Center for Personalized Medicine for Healthy Aging, Tokyo Medical and Dental University, Yushima 1-5-45, Bunkyo-ku, Tokyo 113-8519, Japan.
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33
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VEGF alleviates ALS-CSF induced cytoplasmic accumulations of TDP-43 and FUS/TLS in NSC-34 cells. J Chem Neuroanat 2017; 81:48-52. [PMID: 28163215 DOI: 10.1016/j.jchemneu.2017.01.007] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2016] [Revised: 01/24/2017] [Accepted: 01/24/2017] [Indexed: 12/12/2022]
Abstract
Cytoplasmic mislocalisation and aggregation of TDP-43 and FUS/TLS proteins in spinal motor neurons contribute to the pathogenesis of the highly fatal disorder amyotrophic lateral sclerosis (ALS). We investigated the neuroprotective effect of VEGF on expression of these proteins in the motor neuronal cell line NSC-34 modelled to reminisce sporadic form of ALS. We studied the expression of TDP-43 and FUS/TLS proteins after exposure to ALS-CSF and following VEGF supplementation by quantitative confocal microscopy and electron microscopy. ALS-CSF caused cytoplasmic overexpression of both the proteins and stress-granule formation in the cells. These alterations were alleviated by VEGF supplementation. The related ultrastructural changes like nuclear membrane dysmorphism and p-bodies associated changes were also reversed. However the protein expression did not completely translocate to the nucleus, as some cells continued to show to cytoplasmic mislocalisation. Thus, the present findings indicate that VEGF alleviates TDP43 and FUS pathology by complimenting its role in controlling apoptosis and reversing choline acetyl transferase expression. Hence, VEGF appears to target multiple pathogenic processes in the neurodegenerative cascade of ALS.
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34
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Abstract
TDP-43 is a dimeric nuclear protein that plays a central role in RNA metabolism. In recent years, this protein has become a focal point of research in the amyotrophic lateral sclerosis and frontotemporal dementia (ALS/FTD) disease spectrum, as pathognomonic inclusions within affected neurons contain post-translationally modified TDP-43. A key question in TDP-43 research involves determining the mechanisms and triggers that cause TDP-43 to form pathological aggregates. This review gives a brief overview of the physiological and pathological roles of TDP-43 and focuses on the structural features of its protein domains and how they may contribute to normal protein function and to disease. A special emphasis is placed on the C-terminal prion-like region thought to be implicated in pathology, as it is where nearly all ALS/FTD-associated mutations reside. Recent structural studies of this domain revealed its crucial role in the formation of phase-separated liquid droplets through a partially populated α-helix. This new discovery provides further support for the theory that liquid droplets such as stress granules may be precursors to pathological aggregates, linking environmental effects such as stress to the potential etiology of the disease. The transition of TDP-43 among soluble, droplet, and aggregate phases and the implications of these transitions for pathological aggregation are summarized and discussed.
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Affiliation(s)
- Yulong Sun
- Department of Medical Biophysics, University of Toronto , Toronto, Ontario M5G1L7, Canada
| | - Avijit Chakrabartty
- Department of Medical Biophysics, University of Toronto , Toronto, Ontario M5G1L7, Canada.,Department of Biochemistry, University of Toronto , Toronto, Ontario M5G1L7, Canada
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35
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An L, Harrison PM. The evolutionary scope and neurological disease linkage of yeast-prion-like proteins in humans. Biol Direct 2016; 11:32. [PMID: 27457357 PMCID: PMC4960796 DOI: 10.1186/s13062-016-0134-5] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2016] [Accepted: 07/14/2016] [Indexed: 11/12/2022] Open
Abstract
Background Prions are proteinaceous particles that propagate alternative protein conformations/states to further copies of the same proteins, and are transmitted from cell-to-cell, and organism-to-organism. Prions are usually made of the beta-sheet rich assemblies termed amyloid. The original prion protein PrP causes devastating neurodegenerative disorders in humans and other mammals. In the yeast Saccharomyces cerevisiae, many prion-forming proteins have been observed; a prominent feature of these proteins is an intrinsically disordered domain rich in glutamine (Q) and asparagine (N) residues. Several human proteins that are yeast-prion-like, in particular those with poly-glutamine (poly-Q) expansions, have been experimentally implicated in human neurodegenerative diseases. Results Here, we have constructed a comprehensive list of human yeast-prion-like proteins that are linked to human neurological disease. Surprisingly, different methods to annotate yeast-prion-like proteins in humans have limited intersection. However, independent of annotation method, we find that human yeast-prion-like proteins as a group have a statistically significant genetic linkage to neurological disease, that is caused specifically by linkage to neurodegenerative diseases. This is despite: (i) no especially high expression of yeast-prion-like proteins in the central nervous system, or (ii) no general enrichment of intrinsically disordered proteins in neurological/neurodegenerative diseases. Cytoskeletal proteins are significantly overrepresented in the set of human yeast-prion-like neurological proteins. Whether involved in neurological pathomechanisms or not, yeast-prion-like proteins in humans have very limited conservation outside of Deuterostomia (< ~10 %) with only a handful having prion-like character in both human and S. cerevisiae. The only such protein with a disease linkage is PUB1/TIA1, which functions as a stress granule component. Thus, the yeast-prion-like character of proteins linked to neurodegenerative diseases has not been conserved over the deep evolutionary time since the last common ancestor of yeasts and humans. Conclusion Our results provide a comprehensive picture of yeast-prion-like proteins in humans and contribute to the strategic basis for experimental investigation of the link between yeast-prion-like protein character and neurological disease. Reviewers Reviewed by Istvan Simon and Alexander Schleiffer. For the full reviews, please go to the Reviewers’ comments section. Electronic supplementary material The online version of this article (doi:10.1186/s13062-016-0134-5) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Lu An
- Department of Biology, McGill University, Montreal, QC, Canada
| | - Paul M Harrison
- Department of Biology, McGill University, Montreal, QC, Canada.
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Wei Y, Lim L, Wang L, Song J. Inter-domain interactions of TDP-43 as decoded by NMR. Biochem Biophys Res Commun 2016; 473:614-9. [PMID: 27040765 DOI: 10.1016/j.bbrc.2016.03.158] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2016] [Accepted: 03/30/2016] [Indexed: 10/22/2022]
Abstract
TDP-43 inclusions have been found in ∼97% ALS as well as an increasing spectrum of other neurodegenerative diseases including Alzheimer's. TDP-43 contains an ubiquitin-like fold, two RRMs and a prion-like domain, but whether they interact with each other remains unknown due to being intrinsically aggregation-prone. Nevertheless, this knowledge is pivotal to understanding physiological functions and pathological roles of TDP-43. Here as facilitated by our previous discovery which allowed NMR characterization of TDP-43 and its five dissected fragments, we successfully decoded that TDP-43 does have dynamic inter-domain interactions, which are coordinated by the intrinsically-disordered prion-like domain. Thus, TDP-43 appears to undergo conformational exchanges between "closed" and "open" states which are needed for its functions. Our study thus offers a mechanism by which cellular processes might control TDP-43 physiology and proteinopathy by mediating its inter-domain interactions.
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Affiliation(s)
- Yuanyuan Wei
- NUS Graduate School for Integrative Sciences and Engineering, National University of Singapore, Singapore
| | - Liangzhong Lim
- Department of Biological Sciences, Faculty of Science, National University of Singapore, 10 Kent Ridge Crescent, Singapore 119260
| | - Lu Wang
- Department of Biological Sciences, Faculty of Science, National University of Singapore, 10 Kent Ridge Crescent, Singapore 119260
| | - Jianxing Song
- NUS Graduate School for Integrative Sciences and Engineering, National University of Singapore, Singapore; Department of Biological Sciences, Faculty of Science, National University of Singapore, 10 Kent Ridge Crescent, Singapore 119260.
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Mass spectrometric analysis of accumulated TDP-43 in amyotrophic lateral sclerosis brains. Sci Rep 2016; 6:23281. [PMID: 26980269 PMCID: PMC4793195 DOI: 10.1038/srep23281] [Citation(s) in RCA: 101] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2015] [Accepted: 03/03/2016] [Indexed: 12/12/2022] Open
Abstract
TDP-43 is the major disease-associated protein involved in the pathogenesis and progression of amyotrophic lateral sclerosis (ALS) and frontotemporal lobar degeneration with ubiquitin-positive inclusions linked to TDP-43 pathology (FTLD-TDP). Abnormal phosphorylation, truncation and cytoplasmic mis-localization are known to be the characteristics for the aggregated forms of TDP-43, and gain of toxic abnormal TDP-43 or loss of function of physiological TDP-43 have been suggested as the cause of neurodegeneration. However, most of the post-translational modifications or truncation sites in the abnormal TDP-43 in brains of patients remain to be identified by protein chemical analysis. In this study, we carried out a highly sensitive liquid chromatography-mass spectrometry analysis of Sarkosyl-insoluble pathological TDP-43 from brains of ALS patients and identified several novel phosphorylation sites, deamidation sites, and cleavage sites. Almost all modifications were localized in the Gly-rich C-terminal half. Most of the cleavage sites identified in this study are novel and are located in N-terminal half, suggesting that these sites may be more accessible to proteolytic enzymes. The data obtained in this study provide a foundation for the molecular mechanisms of TDP-43 aggregation and ALS pathogenesis.
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He RY, Huang YC, Chiang CW, Tsai YJ, Ye TJ, Gao HD, Wu CY, Lee HM, Huang JJT. Characterization and real-time imaging of the FTLD-related protein aggregation induced by amyloidogenic peptides. Chem Commun (Camb) 2016; 51:8652-5. [PMID: 25905771 DOI: 10.1039/c5cc00513b] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We identify a new amyloidogenic peptide from the glutamine/asparagine-rich region of the FTLD-related protein (TDP-43), which can seed both the full-length and N-terminus-truncated TDP-43. Through the microinjection and real-time fluorescence imaging, we also found that this novel peptide could trigger cell apoptosis and initiate TDP-43 aggregation in the cytosol.
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Affiliation(s)
- Ruei-Yu He
- Institute of Chemistry, Academia Sinica, No. 128, Sec. 2, Academia Road, Nankang, Taipei 115, Taiwan.
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Lim L, Wei Y, Lu Y, Song J. ALS-Causing Mutations Significantly Perturb the Self-Assembly and Interaction with Nucleic Acid of the Intrinsically Disordered Prion-Like Domain of TDP-43. PLoS Biol 2016; 14:e1002338. [PMID: 26735904 PMCID: PMC4703307 DOI: 10.1371/journal.pbio.1002338] [Citation(s) in RCA: 135] [Impact Index Per Article: 16.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2015] [Accepted: 11/25/2015] [Indexed: 12/13/2022] Open
Abstract
TAR-DNA-binding protein-43 (TDP-43) C-terminus encodes a prion-like domain widely presented in RNA-binding proteins, which functions to form dynamic oligomers and also, amazingly, hosts most amyotrophic lateral sclerosis (ALS)-causing mutations. Here, as facilitated by our previous discovery, by circular dichroism (CD), fluorescence and nuclear magnetic resonance (NMR) spectroscopy, we have successfully determined conformations, dynamics, and self-associations of the full-length prion-like domains of the wild type and three ALS-causing mutants (A315E, Q331K, and M337V) in both aqueous solutions and membrane environments. The study decodes the following: (1) The TDP-43 prion-like domain is intrinsically disordered only with some nascent secondary structures in aqueous solutions, but owns the capacity to assemble into dynamic oligomers rich in β-sheet structures. By contrast, despite having highly similar conformations, three mutants gained the ability to form amyloid oligomers. The wild type and three mutants all formed amyloid fibrils after incubation as imaged by electron microscopy. (2) The interaction with nucleic acid enhances the self-assembly for the wild type but triggers quick aggregation for three mutants. (3) A membrane-interacting subdomain has been identified over residues Met311-Gln343 indispensable for TDP-43 neurotoxicity, which transforms into a well-folded Ω-loop-helix structure in membrane environments. Furthermore, despite having very similar membrane-embedded conformations, three mutants will undergo further self-association in the membrane environment. Our study implies that the TDP-43 prion-like domain appears to have an energy landscape, which allows the assembly of the wild-type sequence into dynamic oligomers only under very limited condition sets, and ALS-causing point mutations are sufficient to remodel it to more favor the amyloid formation or irreversible aggregation, thus supporting the emerging view that the pathologic aggregation may occur via the exaggeration of functionally important assemblies. Furthermore, the coupled capacity of TDP-43 in aggregation and membrane interaction may critically account for its high neurotoxicity, and therefore its decoupling may represent a promising therapeutic strategy to treat TDP-43 causing neurodegenerative diseases. The prion-like domain of TDP-43 appears to have an energy landscape that allows oligomerisation only under very limited conditions; however, TDP-43 mutations that cause amyotrophic lateral sclerosis are sufficient to remodel the protein in favor of amyloid formation. Amyotrophic lateral sclerosis (ALS) is the most prevalent fatal motor neuron disease. It was identified ~140 years ago, but the exact mechanism underlying the disease has still not been well defined. TAR-DNA-binding protein-43 (TDP-43) was identified as the major component of the proteinaceous inclusions present in ~97% ALS and ~45% frontotemporal dementia (FTD) patients, and has also been observed in an increasing spectrum of other neurodegenerative disorders, including Alzheimer disease. The TDP-43 C-terminus is a key domain—it encodes a prion-like domain and, crucially, hosts almost all ALS-causing mutations. Here we have successfully determined the conformations, dynamics, and self-associations of the prion-like domains of both wild type and three ALS-causing mutants in both aqueous solutions and membrane environments. The study suggests that the TDP-43 prion-like domain appears to have a unique energy landscape, which allows the assembly of the wild-type sequence into specific oligomers only under very limited conditions. Intriguingly, ALS-causing point mutations remodel the energy landscape to favor amyloid formation or irreversible aggregation, thus supporting the emerging view that pathologic aggregation may occur via the exaggeration of functionally important assemblies. Furthermore, the coupled capacity of TDP-43 in aggregation and membrane interaction may partly account for its high neurotoxicity; decoupling these may therefore represent a promising therapeutic strategy to treat TDP-43-mediated neurodegenerative diseases.
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Affiliation(s)
- Liangzhong Lim
- Department of Biological Sciences, Faculty of Science, National University of Singapore, Singapore
| | - Yuanyuan Wei
- NUS Graduate School for Integrative Sciences and Engineering, National University of Singapore, Singapore
| | - Yimei Lu
- Department of Biological Sciences, Faculty of Science, National University of Singapore, Singapore
| | - Jianxing Song
- Department of Biological Sciences, Faculty of Science, National University of Singapore, Singapore
- NUS Graduate School for Integrative Sciences and Engineering, National University of Singapore, Singapore
- * E-mail:
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Bengoechea R, Pittman SK, Tuck EP, True HL, Weihl CC. Myofibrillar disruption and RNA-binding protein aggregation in a mouse model of limb-girdle muscular dystrophy 1D. Hum Mol Genet 2015; 24:6588-602. [PMID: 26362252 PMCID: PMC4634370 DOI: 10.1093/hmg/ddv363] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2015] [Revised: 09/02/2015] [Accepted: 09/02/2015] [Indexed: 12/15/2022] Open
Abstract
Limb-girdle muscular dystrophy type 1D (LGMD1D) is caused by dominantly inherited missense mutations in DNAJB6, an Hsp40 co-chaperone. LGMD1D muscle has rimmed vacuoles and inclusion bodies containing DNAJB6, Z-disc proteins and TDP-43. DNAJB6 is expressed as two isoforms; DNAJB6a and DNAJB6b. Both isoforms contain LGMD1D mutant residues and are expressed in human muscle. To identify which mutant isoform confers disease pathogenesis and generate a mouse model of LGMD1D, we evaluated DNAJB6 expression and localization in skeletal muscle as well as generating DNAJB6 isoform specific expressing transgenic mice. DNAJB6a localized to myonuclei while DNAJB6b was sarcoplasmic. LGMD1D mutations in DNAJB6a or DNAJB6b did not alter this localization in mouse muscle. Transgenic mice expressing the LGMD1D mutant, F93L, in DNAJB6b under a muscle-specific promoter became weak, had early lethality and developed muscle pathology consistent with myopathy after 2 months; whereas mice expressing the same F93L mutation in DNAJB6a or overexpressing DNAJB6a or DNAJB6b wild-type transgenes remained unaffected after 1 year. DNAJB6b localized to the Z-disc and DNAJB6b-F93L expressing mouse muscle had myofibrillar disorganization and desmin inclusions. Consistent with DNAJB6 dysfunction, keratin 8/18, a DNAJB6 client also accumulated in DNAJB6b-F93L expressing mouse muscle. The RNA-binding proteins hnRNPA1 and hnRNPA2/B1 accumulated and co-localized with DNAJB6 at sarcoplasmic stress granules suggesting that these proteins maybe novel DNAJB6b clients. Similarly, hnRNPA1 and hnRNPA2/B1 formed sarcoplasmic aggregates in patients with LGMD1D. Our data support that LGMD1D mutations in DNAJB6 disrupt its sarcoplasmic function suggesting a role for DNAJB6b in Z-disc organization and stress granule kinetics.
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Affiliation(s)
| | | | | | - Heather L True
- Department of Cell Biology and Physiology and and The Hope Center for Neurological Diseases, Washington University School of Medicine, St Louis, MO 63110, USA
| | - Conrad C Weihl
- Department of Neurology, The Hope Center for Neurological Diseases, Washington University School of Medicine, St Louis, MO 63110, USA
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Smethurst P, Sidle KCL, Hardy J. Review: Prion-like mechanisms of transactive response DNA binding protein of 43 kDa (TDP-43) in amyotrophic lateral sclerosis (ALS). Neuropathol Appl Neurobiol 2015; 41:578-97. [PMID: 25487060 DOI: 10.1111/nan.12206] [Citation(s) in RCA: 63] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2014] [Accepted: 12/03/2014] [Indexed: 01/13/2023]
Abstract
Amyotrophic lateral sclerosis (ALS) is a fatal devastating neurodegenerative disorder which predominantly affects the motor neurons in the brain and spinal cord. The death of the motor neurons in ALS causes subsequent muscle atrophy, paralysis and eventual death. Clinical and biological evidence now demonstrates that ALS has many similarities to prion disease in terms of disease onset, phenotype variability and progressive spread. The pathognomonic ubiquitinated inclusions deposited in the neurons and glial cells in brains and spinal cords of patients with ALS and fronto-temporal lobar degeneration with ubiquitinated inclusions contain aggregated transactive response DNA binding protein of 43 kDa (TDP-43), and evidence now suggests that TDP-43 has cellular prion-like properties. The cellular mechanisms of prion protein misfolding and aggregation are thought to be responsible for the characteristics of prion disease. Therefore, there is a strong mechanistic basis for a prion-like behaviour of the TDP-43 protein being responsible for some characteristics of ALS. In this review, we compare the prion-like mechanisms of TDP-43 to the clinical and biological nature of ALS in order to investigate how this protein could be responsible for some of the characteristic properties of the disease.
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Affiliation(s)
- Phillip Smethurst
- Department of Molecular Neuroscience, UCL Institute of Neurology, Queen Square House, London, UK
| | | | - John Hardy
- Department of Molecular Neuroscience, UCL Institute of Neurology, Queen Square House, London, UK
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42
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Grad LI, Fernando SM, Cashman NR. From molecule to molecule and cell to cell: prion-like mechanisms in amyotrophic lateral sclerosis. Neurobiol Dis 2015; 77:257-65. [PMID: 25701498 DOI: 10.1016/j.nbd.2015.02.009] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2014] [Revised: 08/13/2014] [Accepted: 02/09/2015] [Indexed: 12/12/2022] Open
Abstract
Prions, self-proliferating infectious agents consisting of misfolded protein, are most often associated with aggressive neurodegenerative diseases in animals and humans. Akin to the contiguous spread of a living pathogen, the prion paradigm provides a mechanism by which a mutant or wild-type misfolded protein can dominate pathogenesis through self-propagating protein misfolding, and subsequently spread from region to region through the central nervous system. The prion diseases, along with more common neurodegenerative disorders such as Alzheimer's disease, Parkinson's disease and the tauopathies belong to a larger group of protein misfolding disorders termed proteinopathies that feature aberrant misfolding and aggregation of specific proteins. Amyotrophic lateral sclerosis (ALS), a lethal disease characterized by progressive degeneration of motor neurons is currently understood as a classical proteinopathy; the disease is typified by the formation of inclusions consisting of aggregated protein within motor neurons that contribute to neurotoxicity. It is well established that misfolded/aggregated proteins such as SOD1 and TDP-43 contribute to the toxicity of motor neurons and play a prominent role in the pathology of ALS. Recent work has identified propagated protein misfolding properties in both mutant and wild-type SOD1, and to a lesser extent TDP-43, which may provide the molecular basis for the clinically observed contiguous spread of the disease through the neuroaxis. In this review we examine the current state of knowledge regarding the prion-like properties of proteins associated with ALS pathology as well as their possible mechanisms of transmission.
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Affiliation(s)
- Leslie I Grad
- Department of Medicine (Neurology), Brain Research Centre, University of British Columbia, 2211 Wesbrook Mall, Vancouver BC, Canada, V6T 2B5
| | - Sarah M Fernando
- Department of Medicine (Neurology), Brain Research Centre, University of British Columbia, 2211 Wesbrook Mall, Vancouver BC, Canada, V6T 2B5
| | - Neil R Cashman
- Department of Medicine (Neurology), Brain Research Centre, University of British Columbia, 2211 Wesbrook Mall, Vancouver BC, Canada, V6T 2B5.
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43
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Self-assembled FUS binds active chromatin and regulates gene transcription. Proc Natl Acad Sci U S A 2014; 111:17809-14. [PMID: 25453086 DOI: 10.1073/pnas.1414004111] [Citation(s) in RCA: 104] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Amyotrophic lateral sclerosis (ALS) is a progressive neurodegenerative disease. Fused in sarcoma (FUS) is a DNA/RNA binding protein and mutations in FUS cause a subset of familial ALS. Most ALS mutations are clustered in the C-terminal nuclear localization sequence of FUS and consequently lead to the accumulation of protein inclusions in the cytoplasm. It remains debatable whether loss of FUS normal function in the nucleus or gain of toxic function in the cytoplasm plays a more critical role in the ALS etiology. Moreover, the physiological function of FUS in the nucleus remains to be fully understood. In this study, we found that a significant portion of nuclear FUS was bound to active chromatin and that the ALS mutations dramatically decreased FUS chromatin binding ability. Functionally, the chromatin binding is required for FUS transcription activation, but not for alternative splicing regulation. The N-terminal QGSY (glutamine-glycine-serine-tyrosine)-rich region (amino acids 1-164) mediates FUS self-assembly in the nucleus of mammalian cells and the self-assembly is essential for its chromatin binding and transcription activation. In addition, RNA binding is also required for FUS self-assembly and chromatin binding. Together, our results suggest a functional assembly of FUS in the nucleus under physiological conditions, which is different from the cytoplasmic inclusions. The ALS mutations can cause loss of function in the nucleus by disrupting this assembly and chromatin binding.
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Diner I, Hales CM, Bishof I, Rabenold L, Duong DM, Yi H, Laur O, Gearing M, Troncoso J, Thambisetty M, Lah JJ, Levey AI, Seyfried NT. Aggregation properties of the small nuclear ribonucleoprotein U1-70K in Alzheimer disease. J Biol Chem 2014; 289:35296-313. [PMID: 25355317 DOI: 10.1074/jbc.m114.562959] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Recent evidence indicates that U1-70K and other U1 small nuclear ribonucleoproteins are Sarkosyl-insoluble and associate with Tau neurofibrillary tangles selectively in Alzheimer disease (AD). Currently, the mechanisms underlying the conversion of soluble nuclear U1 small nuclear ribonucleoproteins into insoluble cytoplasmic aggregates remain elusive. Based on the biochemical and subcellular distribution properties of U1-70K in AD, we hypothesized that aggregated U1-70K itself or other biopolymers (e.g. proteins or nucleic acids) interact with and sequester natively folded soluble U1-70K into insoluble aggregates. Here, we demonstrate that total homogenates from AD brain induce soluble U1-70K from control brain or recombinant U1-70K to become Sarkosyl-insoluble. This effect was not dependent on RNA and did not correlate with detergent-insoluble Tau levels as AD homogenates with reduced levels of these components were still capable of inducing U1-70K aggregation. In contrast, proteinase K-treated AD homogenates and Sarkosyl-soluble AD fractions were unable to induce U1-70K aggregation, indicating that aggregated proteins in AD brain are responsible for inducing soluble U1-70K aggregation. It was determined that the C terminus of U1-70K, which harbors two disordered low complexity (LC) domains, is necessary for U1-70K aggregation. Moreover, both LC1 and LC2 domains were sufficient for aggregation. Finally, protein cross-linking and mass spectrometry studies demonstrated that a U1-70K fragment harboring the LC1 domain directly interacts with aggregated U1-70K in AD brain. Our results support a hypothesis that aberrant forms of U1-70K in AD can directly sequester soluble forms of U1-70K into insoluble aggregates.
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Affiliation(s)
- Ian Diner
- From the Departments of Biochemistry and the Center for Neurodegenerative Disease, Emory University School of Medicine, Atlanta, Georgia 30322
| | - Chadwick M Hales
- the Center for Neurodegenerative Disease, Emory University School of Medicine, Atlanta, Georgia 30322 Neurology
| | - Isaac Bishof
- From the Departments of Biochemistry and the Center for Neurodegenerative Disease, Emory University School of Medicine, Atlanta, Georgia 30322
| | - Lake Rabenold
- From the Departments of Biochemistry and the Center for Neurodegenerative Disease, Emory University School of Medicine, Atlanta, Georgia 30322
| | - Duc M Duong
- From the Departments of Biochemistry and the Center for Neurodegenerative Disease, Emory University School of Medicine, Atlanta, Georgia 30322
| | - Hong Yi
- Emory University School of Medicine, Atlanta, Georgia 30322 Robert P. Apkarian Integrated Electron Microscopy Core
| | - Oskar Laur
- Emory University School of Medicine, Atlanta, Georgia 30322 Division of Microbiology, and Yerkes Research Center, Emory University, Atlanta, Georgia 30322
| | - Marla Gearing
- the Center for Neurodegenerative Disease, Emory University School of Medicine, Atlanta, Georgia 30322 the Departments of Experimental Pathology and
| | - Juan Troncoso
- Pathology and Neurology, Johns Hopkins School of Medicine, Baltimore, Maryland 21205
| | | | - James J Lah
- the Center for Neurodegenerative Disease, Emory University School of Medicine, Atlanta, Georgia 30322 Neurology
| | - Allan I Levey
- the Center for Neurodegenerative Disease, Emory University School of Medicine, Atlanta, Georgia 30322 Neurology
| | - Nicholas T Seyfried
- From the Departments of Biochemistry and the Center for Neurodegenerative Disease, Emory University School of Medicine, Atlanta, Georgia 30322 Neurology,
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Sun Y, Arslan PE, Won A, Yip CM, Chakrabartty A. Binding of TDP-43 to the 3'UTR of its cognate mRNA enhances its solubility. Biochemistry 2014; 53:5885-94. [PMID: 25171271 DOI: 10.1021/bi500617x] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
TAR DNA binding protein of 43 kDa (TDP-43) has been implicated in the pathogenesis of a broad range of neurodegenerative diseases termed TDP-43 proteinopathies, which encompass a spectrum of diseases ranging from amyotrophic lateral sclerosis to frontotemporal dementia. Pathologically misfolded and aggregated forms of TDP-43 are found in cytoplasmic inclusion bodies of affected neurons in these diseases. The mechanism by which TDP-43 misfolding causes disease is not well-understood. Current hypotheses postulate that the TDP-43 aggregation process plays a major role in pathogenesis. We amplify that hypothesis and suggest that binding of cognate ligands to TDP-43 can stabilize the native functional state of the protein and ameliorate aggregation. We expressed recombinant TDP-43 containing an N-terminal Venus yellow fluorescent protein tag in Escherichia coli and induced its aggregation by altering solvent salt concentrations and examined the extent to which various oligonucleotide molecules affect its aggregation in vitro using aggregation-induced turbidity assays. We show that vYFP-TDP-43 binding to its naturally occurring RNA target that comprises a sequence on the 3'UTR region of its mRNA improves its solubility, suggesting interplay among TDP-43 solubility, oligonucleotide binding, and TDP-43 autoregulation.
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Affiliation(s)
- Yulong Sun
- Department of Medical Biophysics, University of Toronto , Toronto, Ontario M5G 1L7, Canada
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Nussbaum-Krammer CI, Morimoto RI. Caenorhabditis elegans as a model system for studying non-cell-autonomous mechanisms in protein-misfolding diseases. Dis Model Mech 2014; 7:31-9. [PMID: 24396152 PMCID: PMC3882046 DOI: 10.1242/dmm.013011] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
Caenorhabditis elegans has a number of distinct advantages that are useful for understanding the basis for cellular and organismal dysfunction underlying age-associated diseases of protein misfolding. Although protein aggregation, a key feature of human neurodegenerative diseases, has been typically explored in vivo at the single-cell level using cells in culture, there is now increasing evidence that proteotoxicity has a non-cell-autonomous component and is communicated between cells and tissues in a multicellular organism. These discoveries have opened up new avenues for the use of C. elegans as an ideal animal model system to study non-cell-autonomous proteotoxicity, prion-like propagation of aggregation-prone proteins, and the organismal regulation of stress responses and proteostasis. This Review focuses on recent evidence that C. elegans has mechanisms to transmit certain classes of toxic proteins between tissues and a complex stress response that integrates and coordinates signals from single cells and tissues across the organism. These findings emphasize the potential of C. elegans to provide insights into non-cell-autonomous proteotoxic mechanisms underlying age-related protein-misfolding diseases.
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Affiliation(s)
- Carmen I Nussbaum-Krammer
- Department of Molecular Biosciences, Rice Institute for Biomedical Research, Northwestern University, 2205 Tech Drive, Evanston, IL 60208, USA
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47
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D'Alton S, Lewis J. Therapeutic and diagnostic challenges for frontotemporal dementia. Front Aging Neurosci 2014; 6:204. [PMID: 25191265 PMCID: PMC4137452 DOI: 10.3389/fnagi.2014.00204] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2014] [Accepted: 07/25/2014] [Indexed: 12/12/2022] Open
Abstract
In the search for therapeutic modifiers, frontotemporal dementia (FTD) has traditionally been overshadowed by other conditions such as Alzheimer's disease (AD). A clinically and pathologically diverse condition, FTD has been galvanized by a number of recent discoveries such as novel genetic variants in familial and sporadic forms of disease and the identification of TAR DNA binding protein of 43 kDa (TDP-43) as the defining constituent of inclusions in more than half of cases. In combination with an ever-expanding knowledge of the function and dysfunction of tau-a protein which is pathologically aggregated in the majority of the remaining cases-there exists a greater understanding of FTD than ever before. These advances may indicate potential approaches for the development of hypothetical therapeutics, but FTD remains highly complex and the roles of tau and TDP-43 in neurodegeneration are still wholly unclear. Here the challenges facing potential therapeutic strategies are discussed, which include sufficiently accurate disease diagnosis and sophisticated technology to deliver effective therapies.
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Affiliation(s)
- Simon D'Alton
- Department of Neuroscience, Center for Translational Research in Neurodegenerative Disease, College of Medicine, University of Florida Gainesville, FL, USA
| | - Jada Lewis
- Department of Neuroscience, Center for Translational Research in Neurodegenerative Disease, College of Medicine, University of Florida Gainesville, FL, USA
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48
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Sun CS, Wang CYH, Chen BPW, He RY, Liu GCH, Wang CH, Chen W, Chern Y, Huang JJT. The influence of pathological mutations and proline substitutions in TDP-43 glycine-rich peptides on its amyloid properties and cellular toxicity. PLoS One 2014; 9:e103644. [PMID: 25090004 PMCID: PMC4121164 DOI: 10.1371/journal.pone.0103644] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2014] [Accepted: 07/01/2014] [Indexed: 12/13/2022] Open
Abstract
TAR DNA-binding protein (TDP-43) was identified as the major ubiquitinated component deposited in the inclusion bodies in amyotrophic lateral sclerosis (ALS) and frontotemporal lobar degeneration with ubiquitin-positive inclusions (FTLD-U) in 2006. Later on, numerous ALS-related mutations were found in either the glycine or glutamine/asparagine-rich region on the TDP-43 C-terminus, which hinted on the importance of mutations on the disease pathogenesis. However, how the structural conversion was influenced by the mutations and the biological significance of these peptides remains unclear. In this work, various peptides bearing pathogenic or de novo designed mutations were synthesized and displayed their ability to form twisted amyloid fibers, cause liposome leakage, and mediate cellular toxicity as confirmed by transmission electron microscopy (TEM), circular dichroism (CD), Thioflavin T (ThT) assay, Raman spectroscopy, calcein leakage assay, and cell viability assay. We have also shown that replacing glycines with prolines, known to obstruct β-sheet formation, at the different positions in these peptides may influence the amyloidogenesis process and neurotoxicity. In these cases, GGG308PPP mutant was not able to form beta-amyloid, cause liposome leakage, nor jeopardized cell survival, which hinted on the importance of the glycines (308-310) during amyloidogenesis.
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Affiliation(s)
- Chia-Sui Sun
- Taiwan International Graduate Program in Molecular Medicine, National Yang-Ming University and Academia Sinica, Taipei, Taiwan
- Institute of Chemistry, Academia Sinica, Taipei, Taiwan
- Institute of Biomedical Sciences, Academia Sinica, Taipei, Taiwan
- Institute of Biochemistry and Molecular Biology, National Yang-Ming University, Taipei, Taiwan
| | - Cindy Yu-Hsiang Wang
- Institute of Chemistry, Academia Sinica, Taipei, Taiwan
- Department of Chemistry, National Taiwan University, Taipei, Taiwan
| | | | - Ruei-Yu He
- Institute of Chemistry, Academia Sinica, Taipei, Taiwan
| | - Gerard Chun-Hao Liu
- Institute of Chemistry, Academia Sinica, Taipei, Taiwan
- Department of Chemistry, National Taiwan University, Taipei, Taiwan
| | - Chih-Hsien Wang
- Department of Applied Chemistry, National Chiayi University, Chiayi, Taiwan
| | - Wenlung Chen
- Department of Applied Chemistry, National Chiayi University, Chiayi, Taiwan
| | - Yijuang Chern
- Institute of Biomedical Sciences, Academia Sinica, Taipei, Taiwan
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49
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Chang HY, Hou SC, Way TD, Wong CH, Wang IF. Heat-shock protein dysregulation is associated with functional and pathological TDP-43 aggregation. Nat Commun 2014; 4:2757. [PMID: 24220679 DOI: 10.1038/ncomms3757] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2013] [Accepted: 10/14/2013] [Indexed: 01/05/2023] Open
Abstract
Conformational disorders are involved in various neurodegenerative diseases. Reactive oxygen species (ROS) are the major contributors to neurodegenerative disease; however, ROS that affect the structural changes in misfolded disease proteins have yet to be well characterized. Here we demonstrate that the intrinsic propensity of TDP-43 to aggregate drives the assembly of TDP-43-positive stress granules and soluble toxic TDP-43 oligomers in response to a ROS insult via a disulfide crosslinking-independent mechanism. Notably, ROS-induced TDP-43 protein assembly correlates with the dynamics of certain TDP-43-associated chaperones. The heat-shock protein (HSP)-90 inhibitor 17-AAG prevents ROS-induced TDP-43 aggregation, alters the type of TDP-43 multimers and reduces the severity of pathological TDP-43 inclusions. In summary, our study suggests that a common mechanism could be involved in the pathogenesis of conformational diseases that result from HSP dysregulation.
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Affiliation(s)
- Hsiang-Yu Chang
- 1] Garage Brain Science, Taichung 413, Taiwan [2] Department of Biological Science and Technology, College of Life Sciences, China Medical University, Taichung 404, Taiwan
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50
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Hans F, Fiesel FC, Strong JC, Jäckel S, Rasse TM, Geisler S, Springer W, Schulz JB, Voigt A, Kahle PJ. UBE2E ubiquitin-conjugating enzymes and ubiquitin isopeptidase Y regulate TDP-43 protein ubiquitination. J Biol Chem 2014; 289:19164-79. [PMID: 24825905 DOI: 10.1074/jbc.m114.561704] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Trans-activation element DNA-binding protein of 43 kDa (TDP-43) characterizes insoluble protein aggregates in distinct subtypes of frontotemporal lobar degeneration and amyotrophic lateral sclerosis. TDP-43 mediates many RNA processing steps within distinct protein complexes. Here we identify novel TDP-43 protein interactors found in a yeast two-hybrid screen using an adult human brain cDNA library. We confirmed the TDP-43 interaction of seven hits by co-immunoprecipitation and assessed their co-localization in HEK293E cells. As pathological TDP-43 is ubiquitinated, we focused on the ubiquitin-conjugating enzyme UBE2E3 and the ubiquitin isopeptidase Y (UBPY). When cells were treated with proteasome inhibitor, ubiquitinated and insoluble TDP-43 species accumulated. All three UBE2E family members could enhance the ubiquitination of TDP-43, whereas catalytically inactive UBE2E3(C145S) was much less efficient. Conversely, silencing of UBE2E3 reduced TDP-43 ubiquitination. We examined 15 of the 48 known disease-associated TDP-43 mutants and found that one was excessively ubiquitinated. This strong TDP-43(K263E) ubiquitination was further enhanced by proteasomal inhibition as well as UBE2E3 expression. Conversely, UBE2E3 silencing and expression of UBPY reduced TDP-43(K263E) ubiquitination. Moreover, wild-type but not active site mutant UBPY reduced ubiquitination of TDP-43 C-terminal fragments and of a nuclear import-impaired mutant. In Drosophila melanogaster, UBPY silencing enhanced neurodegenerative TDP-43 phenotypes and the accumulation of insoluble high molecular weight TDP-43 and ubiquitin species. Thus, UBE2E3 and UBPY participate in the regulation of TDP-43 ubiquitination, solubility, and neurodegeneration.
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Affiliation(s)
- Friederike Hans
- From the Graduate School of Cellular and Molecular Neuroscience, University of Tübingen, Tübingen 72076, Germany, Laboratory of Functional Neurogenetics, Department of Neurodegeneration, German Center for Neurodegenerative Diseases (DZNE), Tübingen 72076, Germany, Laboratory of Functional Neurogenetics, Department of Neurodegeneration and
| | - Fabienne C Fiesel
- Laboratory of Functional Neurogenetics, Department of Neurodegeneration and
| | - Jennifer C Strong
- Laboratory of Functional Neurogenetics, Department of Neurodegeneration and
| | - Sandra Jäckel
- Laboratory of Functional Neurogenetics, Department of Neurodegeneration and
| | - Tobias M Rasse
- Synaptic Plasticity Group, Hertie Institute for Clinical Brain Research, Tübingen 72076, Germany
| | - Sven Geisler
- Laboratory of Functional Neurogenetics, Department of Neurodegeneration and
| | - Wolfdieter Springer
- Laboratory of Functional Neurogenetics, Department of Neurodegeneration, German Center for Neurodegenerative Diseases (DZNE), Tübingen 72076, Germany, Laboratory of Functional Neurogenetics, Department of Neurodegeneration and
| | - Jörg B Schulz
- Department of Neurology, University Medical Center, Aachen 52074, Germany, and Jülich Aachen Research Alliance (JARA)-Translational Brain Medicine, Aachen 52074, Germany
| | - Aaron Voigt
- Department of Neurology, University Medical Center, Aachen 52074, Germany, and
| | - Philipp J Kahle
- From the Graduate School of Cellular and Molecular Neuroscience, University of Tübingen, Tübingen 72076, Germany, Laboratory of Functional Neurogenetics, Department of Neurodegeneration, German Center for Neurodegenerative Diseases (DZNE), Tübingen 72076, Germany, Laboratory of Functional Neurogenetics, Department of Neurodegeneration and
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