1
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Ryder BD, Ustyantseva E, Boyer DR, Mendoza-Oliva A, Kuska MI, Wydorski PM, Macierzyńska P, Morgan N, Sawaya MR, Diamond MI, Kampinga HH, Joachimiak LA. DNAJB8 oligomerization is mediated by an aromatic-rich motif that is dispensable for substrate activity. Structure 2024; 32:662-678.e8. [PMID: 38508190 PMCID: PMC11162344 DOI: 10.1016/j.str.2024.02.015] [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: 05/01/2023] [Revised: 01/17/2024] [Accepted: 02/22/2024] [Indexed: 03/22/2024]
Abstract
J-domain protein (JDP) molecular chaperones have emerged as central players that maintain a healthy proteome. The diverse members of the JDP family function as monomers/dimers and a small subset assemble into micron-sized oligomers. The oligomeric JDP members have eluded structural characterization due to their low-complexity, intrinsically disordered middle domains. This in turn, obscures the biological significance of these larger oligomers in protein folding processes. Here, we identified a short, aromatic motif within DNAJB8 that drives self-assembly through π-π stacking and determined its X-ray structure. We show that mutations in the motif disrupt DNAJB8 oligomerization in vitro and in cells. DNAJB8 variants that are unable to assemble bind to misfolded tau seeds more specifically and retain capacity to reduce protein aggregation in vitro and in cells. We propose a new model for DNAJB8 function in which the sequences in the low-complexity domains play distinct roles in assembly and substrate activity.
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Affiliation(s)
- Bryan D Ryder
- Center for Alzheimer's and Neurodegenerative Diseases, Peter O'Donnell Jr. Brain Institute, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Elizaveta Ustyantseva
- Department of Biomedical Sciences of Cells & Systems, University Medical Center Groningen, University of Groningen, Groningen 9713 AV, The Netherlands
| | - David R Boyer
- Molecular Biology Institute, University of California Los Angeles, Los Angeles, CA 90095, USA
| | - Ayde Mendoza-Oliva
- Center for Alzheimer's and Neurodegenerative Diseases, Peter O'Donnell Jr. Brain Institute, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Mikołaj I Kuska
- Center for Alzheimer's and Neurodegenerative Diseases, Peter O'Donnell Jr. Brain Institute, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Paweł M Wydorski
- Center for Alzheimer's and Neurodegenerative Diseases, Peter O'Donnell Jr. Brain Institute, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Paulina Macierzyńska
- Center for Alzheimer's and Neurodegenerative Diseases, Peter O'Donnell Jr. Brain Institute, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Nabil Morgan
- Center for Alzheimer's and Neurodegenerative Diseases, Peter O'Donnell Jr. Brain Institute, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Michael R Sawaya
- Molecular Biology Institute, University of California Los Angeles, Los Angeles, CA 90095, USA
| | - Marc I Diamond
- Center for Alzheimer's and Neurodegenerative Diseases, Peter O'Donnell Jr. Brain Institute, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Harm H Kampinga
- Department of Biomedical Sciences of Cells & Systems, University Medical Center Groningen, University of Groningen, Groningen 9713 AV, The Netherlands
| | - Lukasz A Joachimiak
- Center for Alzheimer's and Neurodegenerative Diseases, Peter O'Donnell Jr. Brain Institute, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA; Department of Biochemistry, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA.
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2
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Carlsson A, Axell E, Emanuelsson C, Olsson U, Linse S. The Ability of DNAJB6b to Suppress Amyloid Formation Depends on the Chaperone Aggregation State. ACS Chem Neurosci 2024; 15:1732-1737. [PMID: 38640082 PMCID: PMC11066835 DOI: 10.1021/acschemneuro.4c00120] [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: 02/26/2024] [Revised: 04/11/2024] [Accepted: 04/15/2024] [Indexed: 04/21/2024] Open
Abstract
For many chaperones, a propensity to self-assemble correlates with function. The highly efficient amyloid suppressing chaperone DNAJB6b has been reported to oligomerize. A key question is whether the DNAJB6b self-assemblies or their subunits are active units in the suppression of amyloid formation. Here, we address this question using a nonmodified chaperone. We use the well-established aggregation kinetics of the amyloid β 42 peptide (Aβ42) as a readout of the amyloid suppression efficiency. The experimental setup relies on the slow dissociation of DNAJB6b assemblies upon dilution. We find that the dissociation of the chaperone assemblies correlates with its ability to suppress fibril formation. Thus, the data show that the subunits of DNAJB6b assemblies rather than the large oligomers are the active forms in amyloid suppression. Our results provide insights into how DNAJB6b operates as a chaperone and illustrate the importance of established assembly equilibria and dissociation rates for the design of kinetic experiments.
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Affiliation(s)
- Andreas Carlsson
- Lund
University, Biochemistry and Structural Biology, Lund, Naturvetarvägen 16, 223 62, Sweden
| | - Emil Axell
- Lund
University, Biochemistry and Structural Biology, Lund, Naturvetarvägen 16, 223 62, Sweden
| | - Cecilia Emanuelsson
- Lund
University, Biochemistry and Structural Biology, Lund, Naturvetarvägen 16, 223 62, Sweden
| | - Ulf Olsson
- Lund
University, Physical Chemistry, Lund, Naturvetarvägen 16, 223 62, Sweden
| | - Sara Linse
- Lund
University, Biochemistry and Structural Biology, Lund, Naturvetarvägen 16, 223 62, Sweden
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3
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Adupa V, Ustyantseva E, Kampinga HH, Onck PR. Tertiary structure and conformational dynamics of the anti-amyloidogenic chaperone DNAJB6b at atomistic resolution. Nat Commun 2024; 15:3285. [PMID: 38627370 PMCID: PMC11021509 DOI: 10.1038/s41467-024-46587-z] [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: 06/15/2023] [Accepted: 03/01/2024] [Indexed: 04/19/2024] Open
Abstract
DNAJB6b is a molecular chaperone of the heat shock protein network, shown to play a crucial role in preventing aggregation of several disease-related intrinsically disordered proteins. Using homology modeling and microsecond-long all-atom molecular dynamics (MD) simulations, we show that monomeric DNAJB6b is a transiently interconverting protein cycling between three states: a closed state, an open state (both abundant), and a less abundant extended state. Interestingly, the reported regulatory autoinhibitory anchor between helix V in the G/F1 region and helices II/III of the J-domain, which obstructs the access of Hsp70 to the J-domain remains present in all three states. This possibly suggests a mechanistically intriguing regulation in which DNAJB6b only becomes exposed when loaded with substrates that require Hsp70 processing. Our MD results of DNAJB6b carrying mutations in the G/F1 region that are linked to limb-girdle muscular dystrophy type D1 (LGMDD1) show that this G/F1 region becomes highly dynamic, pointing towards a spontaneous release of the autoinhibitory helix V from helices II/III. This would increase the probability of non-functional Hsp70 interactions to DNAJB6b without substrates. Our cellular data indeed confirm that non-substrate loaded LGMDD1 mutants have aberrant interactions with Hsp70.
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Affiliation(s)
- Vasista Adupa
- Zernike Institute for Advanced Materials, University of Groningen, Groningen, The Netherlands
| | - Elizaveta Ustyantseva
- Department of Biomedical Sciences, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - Harm H Kampinga
- Department of Biomedical Sciences, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - Patrick R Onck
- Zernike Institute for Advanced Materials, University of Groningen, Groningen, The Netherlands.
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4
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Ryder BD, Ustyantseva E, Boyer DR, Mendoza-Oliva A, Kuska M, Wydorski PM, Macierzynska P, Morgan N, Sawaya MR, Diamond MI, Kampinga HH, Joachimiak L. DNAJB8 oligomerization is mediated by an aromatic-rich motif that is dispensable for substrate activity. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2023.03.06.531355. [PMID: 36945632 PMCID: PMC10028812 DOI: 10.1101/2023.03.06.531355] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/12/2023]
Abstract
J-domain protein (JDP) molecular chaperones have emerged as central players that maintain a healthy proteome. The diverse members of the JDP family function as monomers/dimers and a small subset assemble into micron-sized oligomers. The oligomeric JDP members have eluded structural characterization due to their low-complexity, intrinsically disordered middle domains. This in turn, obscures the biological significance of these larger oligomers in protein folding processes. Here, we identified a short, aromatic motif within DNAJB8, that drives self-assembly through pi-pi stacking and determined its X-ray structure. We show that mutations in the motif disrupt DNAJB8 oligomerization in vitro and in cells. DNAJB8 variants that are unable to assemble bind to misfolded tau seeds more specifically and retain capacity to reduce protein aggregation in vitro and in cells. We propose a new model for DNAJB8 function in which the sequences in the low-complexity domains play distinct roles in assembly and substrate activity.
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5
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Gastelum S, Michael AF, Bolger TA. Saccharomyces cerevisiae as a research tool for RNA-mediated human disease. WILEY INTERDISCIPLINARY REVIEWS. RNA 2023; 15:e1814. [PMID: 37671427 DOI: 10.1002/wrna.1814] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/24/2022] [Revised: 07/25/2023] [Accepted: 07/26/2023] [Indexed: 09/07/2023]
Abstract
The budding yeast, Saccharomyces cerevisiae, has been used for decades as a powerful genetic tool to study a broad spectrum of biological topics. With its ease of use, economic utility, well-studied genome, and a highly conserved proteome across eukaryotes, it has become one of the most used model organisms. Due to these advantages, it has been used to study an array of complex human diseases. From broad, complex pathological conditions such as aging and neurodegenerative disease to newer uses such as SARS-CoV-2, yeast continues to offer new insights into how cellular processes are affected by disease and how affected pathways might be targeted in therapeutic settings. At the same time, the roles of RNA and RNA-based processes have become increasingly prominent in the pathology of many of these same human diseases, and yeast has been utilized to investigate these mechanisms, from aberrant RNA-binding proteins in amyotrophic lateral sclerosis to translation regulation in cancer. Here we review some of the important insights that yeast models have yielded into the molecular pathology of complex, RNA-based human diseases. This article is categorized under: RNA in Disease and Development > RNA in Disease.
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Affiliation(s)
- Stephanie Gastelum
- Department of Molecular and Cellular Biology, University of Arizona, Tucson, Arizona, USA
| | - Allison F Michael
- Department of Biochemistry and Molecular Biology, University of Georgia, Athens, GA, USA
| | - Timothy A Bolger
- Department of Biochemistry and Molecular Biology, University of Georgia, Athens, GA, USA
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6
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Wang S, Sun S. Translation dysregulation in neurodegenerative diseases: a focus on ALS. Mol Neurodegener 2023; 18:58. [PMID: 37626421 PMCID: PMC10464328 DOI: 10.1186/s13024-023-00642-3] [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: 01/03/2023] [Accepted: 07/21/2023] [Indexed: 08/27/2023] Open
Abstract
RNA translation is tightly controlled in eukaryotic cells to regulate gene expression and maintain proteome homeostasis. RNA binding proteins, translation factors, and cell signaling pathways all modulate the translation process. Defective translation is involved in multiple neurological diseases including amyotrophic lateral sclerosis (ALS). ALS is a progressive neurodegenerative disorder and poses a major public health challenge worldwide. Over the past few years, tremendous advances have been made in the understanding of the genetics and pathogenesis of ALS. Dysfunction of RNA metabolisms, including RNA translation, has been closely associated with ALS. Here, we first introduce the general mechanisms of translational regulation under physiological and stress conditions and review well-known examples of translation defects in neurodegenerative diseases. We then focus on ALS-linked genes and discuss the recent progress on how translation is affected by various mutant genes and the repeat expansion-mediated non-canonical translation in ALS.
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Affiliation(s)
- Shaopeng Wang
- Department of Physiology and Brain Science Institute, Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA
| | - Shuying Sun
- Department of Physiology and Brain Science Institute, Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA.
- The Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA.
- Department of Pathology, Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA.
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7
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Carlsson A, Olsson U, Linse S. On the micelle formation of DNAJB6b. QRB DISCOVERY 2023; 4:e6. [PMID: 37593255 PMCID: PMC10427797 DOI: 10.1017/qrd.2023.4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2023] [Revised: 05/22/2023] [Accepted: 07/11/2023] [Indexed: 08/19/2023] Open
Abstract
The human chaperone DNAJB6b increases the solubility of proteins involved in protein aggregation diseases and suppresses the nucleation of amyloid structures. Due to such favourable properties, DNAJB6b has gained increasing attention over the past decade. The understanding of how DNAJB6b operates on a molecular level may aid the design of inhibitors against amyloid formation. In this work, fundamental aspects of DNAJB6b self-assembly have been examined, providing a basis for future experimental designs and conclusions. The results imply the formation of large chaperone clusters in a concentration-dependent manner. Microfluidic diffusional sizing (MDS) was used to evaluate how DNAJB6b average hydrodynamic radius varies with concentration. We found that, in 20 mM sodium phosphate buffer, 0.2 mM EDTA, at pH 8.0 and room temperature, DNAJB6b displays a micellar behaviour, with a critical micelle concentration (CMC) of around 120 nM. The average hydrodynamic radius appears to be concentration independent between ∼10 μM and 100 μM, with a mean radius of about 12 nm. The CMC found by MDS is supported by native agarose gel electrophoresis and the size distribution appears bimodal in the DNAJB6b concentration range ∼100 nM to 4 μM.
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Affiliation(s)
- Andreas Carlsson
- Biochemistry and Structural Biology, Chemical Centre, Lund University, Lund, Sweden
| | - Ulf Olsson
- Physical Chemistry, Chemical Centre, Lund University, Lund, Sweden
| | - Sara Linse
- Biochemistry and Structural Biology, Chemical Centre, Lund University, Lund, Sweden
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8
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Pande S, Ghosh DK. Nuclear proteostasis imbalance in laminopathy-associated premature aging diseases. FASEB J 2023; 37:e23116. [PMID: 37498235 DOI: 10.1096/fj.202300878r] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2023] [Revised: 06/15/2023] [Accepted: 07/13/2023] [Indexed: 07/28/2023]
Abstract
Laminopathies are a group of rare genetic disorders with heterogeneous clinical phenotypes such as premature aging, cardiomyopathy, lipodystrophy, muscular dystrophy, microcephaly, epilepsy, and so on. The cellular phenomena associated with laminopathy invariably show disruption of nucleoskeleton of lamina due to deregulated expression, localization, function, and interaction of mutant lamin proteins. Impaired spatial and temporal tethering of lamin proteins to the lamina or nucleoplasmic aggregation of lamins are the primary molecular events that can trigger nuclear proteotoxicity by modulating differential protein-protein interactions, sequestering quality control proteins, and initiating a cascade of abnormal post-translational modifications. Clearly, laminopathic cells exhibit moderate to high nuclear proteotoxicity, raising the question of whether an imbalance in nuclear proteostasis is involved in laminopathic diseases, particularly in diseases of early aging such as HGPS and laminopathy-associated premature aging. Here, we review nuclear proteostasis and its deregulation in the context of lamin proteins and laminopathies.
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Affiliation(s)
- Shruti Pande
- Department of Medical Genetics, Kasturba Medical College, Manipal, Manipal Academy of Higher Education, Manipal, India
| | - Debasish Kumar Ghosh
- Enteric Disease Division, Department of Microbiology, Kasturba Medical College, Manipal, Manipal Academy of Higher Education, Manipal, India
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9
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Li F, Chen Y, Tang Y, Liu X, Wei G. Dissecting the Effect of ALS Mutation G335D on the Early Aggregation of the TDP-43 Amyloidogenic Core Peptide: Helix-to-β-Sheet Transition and Conformational Shift. J Chem Inf Model 2023; 63:3579-3590. [PMID: 37218694 DOI: 10.1021/acs.jcim.3c00513] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
The aggregation of TAR DNA-binding protein of 43 kDa (TDP-43) into fibrillary deposits is associated with amyotrophic lateral sclerosis (ALS). The 311-360 fragment of TDP-43 (TDP-43311-360), the amyloidogenic core region, can spontaneously aggregate into fibrils, and the ALS-associated mutation G335D has an enhanced effect on TDP-43311-360 fibrillization. However, the molecular mechanism underlying G335D-enhanced aggregation at atomic level remains largely unknown. By utilizing all-atom molecular dynamics (MD) and replica exchange with solute tempering 2 (REST2) simulations, we investigated influences of G335D on the dimerization (the first step of aggregation) and conformational ensemble of the TDP-43311-360 peptide. Our simulations show that G335D mutation increases inter-peptide interactions, especially inter-peptide hydrogen-bonding interactions in which the mutant site has a relatively large contribution, and enhances the dimerization of TDP-43311-360 peptides. The α-helix regions in the NMR-resolved conformation of the TDP-43311-360 monomer (321-330 and 335-343) play an essential role in the formation of the dimer. G335D mutation induces helix unfolding and promotes α-to-β conversion. G335D mutation alters the conformational distribution of TDP-43311-360 dimers and causes population shift from helix-rich to β-sheet-rich conformations, which facilitates the fibrillization of the TDP-43311-360 peptide. Our MD and REST2 simulation results suggest that the 321-330 region is of paramount importance to α-to-β transition and could be the initiation site for TDP-43311-360 fibrillization. Our work reveals the mechanism underlying the enhanced aggregation propensity of the G335D TDP-43311-360 peptide, which provides atomistic insights into the G335D mutation-caused pathogenicity of TDP-43 protein.
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Affiliation(s)
- Fangying Li
- Department of Physics, State Key Laboratory of Surface Physics, and Key Laboratory for Computational Physical Sciences (Ministry of Education), Fudan University, Shanghai 200438, People's Republic of China
| | - Yujie Chen
- Department of Physics, State Key Laboratory of Surface Physics, and Key Laboratory for Computational Physical Sciences (Ministry of Education), Fudan University, Shanghai 200438, People's Republic of China
| | - Yiming Tang
- Department of Physics, State Key Laboratory of Surface Physics, and Key Laboratory for Computational Physical Sciences (Ministry of Education), Fudan University, Shanghai 200438, People's Republic of China
| | - Xianshi Liu
- Department of Physics, State Key Laboratory of Surface Physics, and Key Laboratory for Computational Physical Sciences (Ministry of Education), Fudan University, Shanghai 200438, People's Republic of China
| | - Guanghong Wei
- Department of Physics, State Key Laboratory of Surface Physics, and Key Laboratory for Computational Physical Sciences (Ministry of Education), Fudan University, Shanghai 200438, People's Republic of China
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10
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Kinger S, Dubey AR, Kumar P, Jagtap YA, Choudhary A, Kumar A, Prajapati VK, Dhiman R, Mishra A. Molecular Chaperones' Potential against Defective Proteostasis of Amyotrophic Lateral Sclerosis. Cells 2023; 12:cells12091302. [PMID: 37174703 PMCID: PMC10177248 DOI: 10.3390/cells12091302] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2023] [Revised: 04/24/2023] [Accepted: 04/27/2023] [Indexed: 05/15/2023] Open
Abstract
Amyotrophic lateral sclerosis (ALS) is a neuronal degenerative condition identified via a build-up of mutant aberrantly folded proteins. The native folding of polypeptides is mediated by molecular chaperones, preventing their pathogenic aggregation. The mutant protein expression in ALS is linked with the entrapment and depletion of chaperone capacity. The lack of a thorough understanding of chaperones' involvement in ALS pathogenesis presents a significant challenge in its treatment. Here, we review how the accumulation of the ALS-linked mutant FUS, TDP-43, SOD1, and C9orf72 proteins damage cellular homeostasis mechanisms leading to neuronal loss. Further, we discuss how the HSP70 and DNAJ family co-chaperones can act as potential targets for reducing misfolded protein accumulation in ALS. Moreover, small HSPB1 and HSPB8 chaperones can facilitate neuroprotection and prevent stress-associated misfolded protein apoptosis. Designing therapeutic strategies by pharmacologically enhancing cellular chaperone capacity to reduce mutant protein proteotoxic effects on ALS pathomechanisms can be a considerable advancement. Chaperones, apart from directly interacting with misfolded proteins for protein quality control, can also filter their toxicity by initiating strong stress-response pathways, modulating transcriptional expression profiles, and promoting anti-apoptotic functions. Overall, these properties of chaperones make them an attractive target for gaining fundamental insights into misfolded protein disorders and designing more effective therapies against ALS.
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Affiliation(s)
- Sumit Kinger
- Cellular and Molecular Neurobiology Unit, Indian Institute of Technology Jodhpur, Jodhpur 342037, India
| | - Ankur Rakesh Dubey
- Cellular and Molecular Neurobiology Unit, Indian Institute of Technology Jodhpur, Jodhpur 342037, India
| | - Prashant Kumar
- Cellular and Molecular Neurobiology Unit, Indian Institute of Technology Jodhpur, Jodhpur 342037, India
| | - Yuvraj Anandrao Jagtap
- Cellular and Molecular Neurobiology Unit, Indian Institute of Technology Jodhpur, Jodhpur 342037, India
| | - Akash Choudhary
- Cellular and Molecular Neurobiology Unit, Indian Institute of Technology Jodhpur, Jodhpur 342037, India
| | - Amit Kumar
- Discipline of Biosciences and Biomedical Engineering, Indian Institute of Technology Indore, Simrol, Indore 453552, India
| | - Vijay Kumar Prajapati
- Department of Biochemistry, School of Life Sciences, Central University of Rajasthan, Ajmer 305817, India
| | - Rohan Dhiman
- Laboratory of Mycobacterial Immunology, Department of Life Science, National Institute of Technology, Rourkela 769008, India
| | - Amit Mishra
- Cellular and Molecular Neurobiology Unit, Indian Institute of Technology Jodhpur, Jodhpur 342037, India
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11
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Doke AA, Jha SK. Shapeshifter TDP-43: Molecular mechanism of structural polymorphism, aggregation, phase separation and their modulators. Biophys Chem 2023; 295:106972. [PMID: 36812677 DOI: 10.1016/j.bpc.2023.106972] [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: 12/28/2022] [Revised: 02/09/2023] [Accepted: 02/12/2023] [Indexed: 02/17/2023]
Abstract
TDP-43 is a nucleic acid-binding protein that performs physiologically essential functions and is known to undergo phase separation and aggregation during stress. Initial observations have shown that TDP-43 forms heterogeneous assemblies, including monomer, dimer, oligomers, aggregates, phase-separated assemblies, etc. However, the significance of each assembly of TDP-43 concerning its function, phase separation, and aggregation is poorly known. Furthermore, how different assemblies of TDP-43 are related to each other is unclear. In this review, we focus on the various assemblies of TDP-43 and discuss the plausible origin of the structural heterogeneity of TDP-43. TDP-43 is involved in multiple physiological processes like phase separation, aggregation, prion-like seeding, and performing physiological functions. However, the molecular mechanism behind the physiological process performed by TDP-43 is not well understood. The current review discusses the plausible molecular mechanism of phase separation, aggregation, and prion-like propagation of TDP-43.
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Affiliation(s)
- Abhilasha A Doke
- Physical and Materials Chemistry Division, CSIR-National Chemical Laboratory, Dr. Homi Bhabha Road, Pune 411008, India; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India
| | - Santosh Kumar Jha
- Physical and Materials Chemistry Division, CSIR-National Chemical Laboratory, Dr. Homi Bhabha Road, Pune 411008, India; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India.
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12
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Metamorphism in TDP-43 prion-like domain determines chaperone recognition. Nat Commun 2023; 14:466. [PMID: 36709343 PMCID: PMC9884275 DOI: 10.1038/s41467-023-36023-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2022] [Accepted: 01/12/2023] [Indexed: 01/29/2023] Open
Abstract
The RNA binding protein TDP-43 forms cytoplasmic inclusions via its C-terminal prion-like domain in several neurodegenerative diseases. Aberrant TDP-43 aggregation arises upon phase de-mixing and transitions from liquid to solid states, following still unknown structural conversions which are primed by oxidative stress and chaperone inhibition. Despite the well-established protective roles for molecular chaperones against protein aggregation pathologies, knowledge on the determinants of chaperone recognition in disease-related prions is scarce. Here we show that chaperones and co-chaperones primarily recognize the structured elements in TDP-43´s prion-like domain. Significantly, while HSP70 and HSP90 chaperones promote TDP-43 phase separation, co-chaperones from the three classes of the large human HSP40 family (namely DNAJA2, DNAJB1, DNAJB4 and DNAJC7) show strikingly different effects on TDP-43 de-mixing. Dismantling of the second helical element in TDP-43 prion-like domain by methionine sulfoxidation impacts phase separation and amyloid formation, abrogates chaperone recognition and alters phosphorylation by casein kinase-1δ. Our results show that metamorphism in the post-translationally modified TDP-43 prion-like domain encodes determinants that command mechanisms with major relevance in disease.
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13
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Molecular Investigations of Protein Aggregation in the Pathogenesis of Amyotrophic Lateral Sclerosis. Int J Mol Sci 2022; 24:ijms24010704. [PMID: 36614144 PMCID: PMC9820914 DOI: 10.3390/ijms24010704] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2022] [Revised: 12/20/2022] [Accepted: 12/27/2022] [Indexed: 01/03/2023] Open
Abstract
Amyotrophic lateral sclerosis (ALS) is a devastating progressive neurodegenerative disorder characterized by selective loss of lower and upper motor neurons (MNs) in the brain and spinal cord, resulting in paralysis and eventually death due to respiratory insufficiency. Although the fundamental physiological mechanisms underlying ALS are not completely understood, the key neuropathological hallmarks of ALS pathology are the aggregation and accumulation of ubiquitinated protein inclusions within the cytoplasm of degenerating MNs. Herein, we discuss recent insights into the molecular mechanisms that lead to the accumulation of protein aggregates in ALS. This will contribute to a better understanding of the pathophysiology of the disease and may open novel avenues for the development of therapeutic strategies.
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14
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Staderini T, Bigi A, Mongiello D, Cecchi C, Chiti F. Biophysical characterization of full-length TAR DNA-binding protein (TDP-43) phase separation. Protein Sci 2022; 31:e4509. [PMID: 36371546 PMCID: PMC9703588 DOI: 10.1002/pro.4509] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2022] [Revised: 10/17/2022] [Accepted: 11/05/2022] [Indexed: 11/15/2022]
Abstract
Amyotrophic lateral sclerosis and frontotemporal lobar degeneration with ubiquitin-positive inclusions are associated with deposition of cytosolic inclusion bodies of TAR DNA-binding protein 43 (TDP-43) in brain and motor neurons. We induced phase separation of purified full-length TDP-43 devoid of large tags using a solution-jump method, and monitored it with an array of biophysical techniques. The tetramethylrhodamine-5-maleimide- or Alexa488-labeled protein formed rapidly (<1 min) apparently round, homogeneous and 0.5-1.0 μm wide assemblies, when imaged using confocal fluorescence, bright-field, and stimulated emission depletion microscopy. The assemblies, however, had limited internal diffusion, as assessed with fluorescence recovery after photobleaching, and did not coalesce, but rather clustered into irregular bunches, unlike those formed by the C-terminal domain. They were enriched with α-helical structure, with minor contributions of β-sheet/random structure, had a red-shifted tryptophan fluorescence and did not bind thioflavin T. By monitoring with turbidimetry both the formation of the spherical species and their further clustering under different experimental conditions, we carried out a multiparametric analysis of the two phenomena. In particular, both processes were found to be promoted by high protein concentrations, salts, crowding agents, weakly by reducing agents, as the pH approached a value of 6.0 from either side (corresponding to the TDP-43 isoionic point), and as the temperature approached a value of 31°C from either side. Important differences were found with respect to the TDP-43 C-terminal domain. Our multiparametric results also provide explanations to some of the solubility data obtained on full-length TDP-43 that were difficult to explain following the multiparametric analysis acquired on the C-terminal domain.
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Affiliation(s)
- Tommaso Staderini
- Department of Experimental and Clinical Biomedical Sciences “Mario Serio”University of FlorenceFlorenceItaly
| | - Alessandra Bigi
- Department of Experimental and Clinical Biomedical Sciences “Mario Serio”University of FlorenceFlorenceItaly
| | - Daniele Mongiello
- Department of Experimental and Clinical Biomedical Sciences “Mario Serio”University of FlorenceFlorenceItaly
| | - Cristina Cecchi
- Department of Experimental and Clinical Biomedical Sciences “Mario Serio”University of FlorenceFlorenceItaly
| | - Fabrizio Chiti
- Department of Experimental and Clinical Biomedical Sciences “Mario Serio”University of FlorenceFlorenceItaly
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15
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Lu S, Hu J, Arogundade OA, Goginashvili A, Vazquez-Sanchez S, Diedrich JK, Gu J, Blum J, Oung S, Ye Q, Yu H, Ravits J, Liu C, Yates JR, Cleveland DW. Heat-shock chaperone HSPB1 regulates cytoplasmic TDP-43 phase separation and liquid-to-gel transition. Nat Cell Biol 2022; 24:1378-1393. [PMID: 36075972 PMCID: PMC9872726 DOI: 10.1038/s41556-022-00988-8] [Citation(s) in RCA: 39] [Impact Index Per Article: 19.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2021] [Accepted: 07/28/2022] [Indexed: 01/27/2023]
Abstract
While acetylated, RNA-binding-deficient TDP-43 reversibly phase separates within nuclei into complex droplets (anisosomes) comprised of TDP-43-containing liquid outer shells and liquid centres of HSP70-family chaperones, cytoplasmic aggregates of TDP-43 are hallmarks of multiple neurodegenerative diseases, including amyotrophic lateral sclerosis (ALS). Here we show that transient oxidative stress, proteasome inhibition or inhibition of the ATP-dependent chaperone activity of HSP70 provokes reversible cytoplasmic TDP-43 de-mixing and transition from liquid to gel/solid, independently of RNA binding or stress granules. Isotope labelling mass spectrometry was used to identify that phase-separated cytoplasmic TDP-43 is bound by the small heat-shock protein HSPB1. Binding is direct, mediated through TDP-43's RNA binding and low-complexity domains. HSPB1 partitions into TDP-43 droplets, inhibits TDP-43 assembly into fibrils, and is essential for disassembly of stress-induced TDP-43 droplets. A decrease in HSPB1 promotes cytoplasmic TDP-43 de-mixing and mislocalization. HSPB1 depletion was identified in spinal motor neurons of patients with ALS containing aggregated TDP-43. These findings identify HSPB1 to be a regulator of cytoplasmic TDP-43 phase separation and aggregation.
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Affiliation(s)
- Shan Lu
- Department of Cellular and Molecular Medicine, University of California, San Diego, CA, USA
- Ludwig Institute for Cancer Research, San Diego, CA, USA
| | - Jiaojiao Hu
- Interdisciplinary Research Center on Biology and Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, Shanghai, China
- University of Chinese Academy of Sciences, Beijing, China
| | | | - Alexander Goginashvili
- Department of Cellular and Molecular Medicine, University of California, San Diego, CA, USA
- Ludwig Institute for Cancer Research, San Diego, CA, USA
| | - Sonia Vazquez-Sanchez
- Department of Cellular and Molecular Medicine, University of California, San Diego, CA, USA
- Ludwig Institute for Cancer Research, San Diego, CA, USA
| | | | - Jinge Gu
- Interdisciplinary Research Center on Biology and Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, Shanghai, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Jacob Blum
- Department of Genetics, Stanford University School of Medicine, Stanford, CA, USA
| | - Spencer Oung
- Department of Cellular and Molecular Medicine, University of California, San Diego, CA, USA
- Ludwig Institute for Cancer Research, San Diego, CA, USA
| | - Qiaozhen Ye
- Department of Cellular and Molecular Medicine, University of California, San Diego, CA, USA
| | - Haiyang Yu
- Center for Alzheimer's and Neurodegenerative Diseases, University of Texas Southwestern Medical Center, Dallas, TX, USA
- Department of Molecular Biology, University of Texas Southwestern Medical Center, Dallas, TX, USA
- Peter O'Donnell Jr Brain Institute, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - John Ravits
- Department of Neurosciences, University of California, San Diego, CA, USA
| | - Cong Liu
- Interdisciplinary Research Center on Biology and Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, Shanghai, China
- University of Chinese Academy of Sciences, Beijing, China
| | - John R Yates
- The Scripps Research Institute, La Jolla, CA, USA
| | - Don W Cleveland
- Department of Cellular and Molecular Medicine, University of California, San Diego, CA, USA.
- Ludwig Institute for Cancer Research, San Diego, CA, USA.
- Department of Neurosciences, University of California, San Diego, CA, USA.
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16
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Kiryu-Seo S, Matsushita R, Tashiro Y, Yoshimura T, Iguchi Y, Katsuno M, Takahashi R, Kiyama H. Impaired disassembly of the axon initial segment restricts mitochondrial entry into damaged axons. EMBO J 2022; 41:e110486. [PMID: 36004759 PMCID: PMC9574747 DOI: 10.15252/embj.2021110486] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2022] [Revised: 07/15/2022] [Accepted: 07/20/2022] [Indexed: 11/09/2022] Open
Abstract
The proteasome is essential for cellular responses to various physiological stressors. However, how proteasome function impacts the stress resilience of regenerative damaged motor neurons remains unclear. Here, we develop a unique mouse model using a regulatory element of the activating transcription factor (Atf3) gene to label mitochondria in a damage‐induced manner while simultaneously genetically disrupting the proteasome. Using this model, we observed that in injury‐induced proteasome‐deficient mouse motor neurons, the increase of mitochondrial influx from soma into axons is inhibited because neurons fail to disassemble ankyrin G, an organizer of the axon initial segment (AIS), in a proteasome‐dependent manner. Further, these motor neurons exhibit amyotrophic lateral sclerosis (ALS)‐like degeneration despite having regenerative potential. Selectively vulnerable motor neurons in SOD1G93A ALS mice, which induce ATF3 in response to pathological damage, also fail to disrupt the AIS, limiting the number of axonal mitochondria at a pre‐symptomatic stage. Thus, damage‐induced proteasome‐sensitive AIS disassembly could be a critical post‐translational response for damaged motor neurons to temporarily transit to an immature state and meet energy demands for axon regeneration or preservation.
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Affiliation(s)
- Sumiko Kiryu-Seo
- Department of Functional Anatomy and Neuroscience, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Reika Matsushita
- Department of Functional Anatomy and Neuroscience, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Yoshitaka Tashiro
- Department of Neurology, Kyoto University Graduate School of Medicine, Kyoto, Japan
| | - Takeshi Yoshimura
- Department of Child Development and Molecular Brain Science, United Graduate School of Child Development, Osaka University, Osaka, Japan.,Department of Neuroscience, Baylor College of Medicine, Houston, TX, USA
| | - Yohei Iguchi
- Department of Neurology, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Masahisa Katsuno
- Department of Neurology, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Ryosuke Takahashi
- Department of Neurology, Kyoto University Graduate School of Medicine, Kyoto, Japan
| | - Hiroshi Kiyama
- Department of Functional Anatomy and Neuroscience, Nagoya University Graduate School of Medicine, Nagoya, Japan
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17
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François-Moutal L, Scott DD, Ambrose AJ, Zerio CJ, Rodriguez-Sanchez M, Dissanayake K, May DG, Carlson JM, Barbieri E, Moutal A, Roux KJ, Shorter J, Khanna R, Barmada SJ, McGurk L, Khanna M. Heat shock protein Grp78/BiP/HspA5 binds directly to TDP-43 and mitigates toxicity associated with disease pathology. Sci Rep 2022; 12:8140. [PMID: 35581326 PMCID: PMC9114370 DOI: 10.1038/s41598-022-12191-8] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2021] [Accepted: 05/04/2022] [Indexed: 11/09/2022] Open
Abstract
Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease with no cure or effective treatment in which TAR DNA Binding Protein of 43 kDa (TDP-43) abnormally accumulates into misfolded protein aggregates in affected neurons. It is widely accepted that protein misfolding and aggregation promotes proteotoxic stress. The molecular chaperones are a primary line of defense against proteotoxic stress, and there has been long-standing interest in understanding the relationship between chaperones and aggregated protein in ALS. Of particular interest are the heat shock protein of 70 kDa (Hsp70) family of chaperones. However, defining which of the 13 human Hsp70 isoforms is critical for ALS has presented many challenges. To gain insight into the specific Hsp70 that modulates TDP-43, we investigated the relationship between TDP-43 and the Hsp70s using proximity-dependent biotin identification (BioID) and discovered several Hsp70 isoforms associated with TDP-43 in the nucleus, raising the possibility of an interaction with native TDP-43. We further found that HspA5 bound specifically to the RNA-binding domain of TDP-43 using recombinantly expressed proteins. Moreover, in a Drosophila strain that mimics ALS upon TDP-43 expression, the mRNA levels of the HspA5 homologue (Hsc70.3) were significantly increased. Similarly we observed upregulation of HspA5 in prefrontal cortex neurons from human ALS patients. Finally, overexpression of HspA5 in Drosophila rescued TDP-43-induced toxicity, suggesting that upregulation of HspA5 may have a compensatory role in ALS pathobiology.
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Affiliation(s)
- Liberty François-Moutal
- Department of Pharmacology, College of Medicine, University of Arizona, Tucson, AZ, 85724, USA.,Center for Innovation in Brain Science, Tucson, AZ, 85721, USA
| | - David Donald Scott
- Department of Pharmacology, College of Medicine, University of Arizona, Tucson, AZ, 85724, USA.,Center for Innovation in Brain Science, Tucson, AZ, 85721, USA
| | - Andrew J Ambrose
- Pharmacology and Toxicology, School of Pharmacy, University of Arizona, Tucson, AZ, 85724, USA
| | - Christopher J Zerio
- Pharmacology and Toxicology, School of Pharmacy, University of Arizona, Tucson, AZ, 85724, USA
| | | | - Kumara Dissanayake
- Cell and Developmental Biology, School of Life Sciences, University of Dundee, Dow Street, Dundee, DD1 5EH, UK
| | - Danielle G May
- Enabling Technologies Group, Sanford Research, Sioux Falls, SD, USA
| | - Jacob M Carlson
- Department of Pharmacology, College of Medicine, University of Arizona, Tucson, AZ, 85724, USA.,Center for Innovation in Brain Science, Tucson, AZ, 85721, USA
| | - Edward Barbieri
- Department of Biochemistry and Biophysics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - Aubin Moutal
- Department of Pharmacology, College of Medicine, University of Arizona, Tucson, AZ, 85724, USA.,Center for Innovation in Brain Science, Tucson, AZ, 85721, USA
| | - Kyle J Roux
- Enabling Technologies Group, Sanford Research, Sioux Falls, SD, USA.,Department of Pediatrics, Sanford School of Medicine, University of South Dakota, Sioux Falls, SD, USA
| | - James Shorter
- Department of Pediatrics, Sanford School of Medicine, University of South Dakota, Sioux Falls, SD, USA
| | - Rajesh Khanna
- Department of Pharmacology, College of Medicine, University of Arizona, Tucson, AZ, 85724, USA.,Center for Innovation in Brain Science, Tucson, AZ, 85721, USA
| | - Sami J Barmada
- Department of Neurology, University of Michigan, Ann Arbor, MI, 48109, USA
| | - Leeanne McGurk
- Cell and Developmental Biology, School of Life Sciences, University of Dundee, Dow Street, Dundee, DD1 5EH, UK
| | - May Khanna
- Department of Pharmacology, College of Medicine, University of Arizona, Tucson, AZ, 85724, USA. .,Center for Innovation in Brain Science, Tucson, AZ, 85721, USA. .,Department of Molecular Pathobiology, NYU, New York, NY, USA. .,Department of Molecular Pathobiology, College of Dentistry, NYU, 433 1st Ave, New York, NY, 10010, USA.
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18
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Mohan HM, Trzeciakiewicz H, Pithadia A, Crowley EV, Pacitto R, Safren N, Trotter B, Zhang C, Zhou X, Zhang Y, Basrur V, Paulson HL, Sharkey LM. RTL8 promotes nuclear localization of UBQLN2 to subnuclear compartments associated with protein quality control. Cell Mol Life Sci 2022; 79:176. [PMID: 35247097 PMCID: PMC9376861 DOI: 10.1007/s00018-022-04170-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2021] [Revised: 01/17/2022] [Accepted: 01/25/2022] [Indexed: 11/24/2022]
Abstract
The brain-expressed ubiquilins (UBQLNs) 1, 2 and 4 are a family of ubiquitin adaptor proteins that participate broadly in protein quality control (PQC) pathways, including the ubiquitin proteasome system (UPS). One family member, UBQLN2, has been implicated in numerous neurodegenerative diseases including ALS/FTD. UBQLN2 typically resides in the cytoplasm but in disease can translocate to the nucleus, as in Huntington's disease where it promotes the clearance of mutant Huntingtin. How UBQLN2 translocates to the nucleus and clears aberrant nuclear proteins, however, is not well understood. In a mass spectrometry screen to discover UBQLN2 interactors, we identified a family of small (13 kDa), highly homologous uncharacterized proteins, RTL8, and confirmed the interaction between UBQLN2 and RTL8 both in vitro using recombinant proteins and in vivo using mouse brain tissue. Under endogenous and overexpressed conditions, RTL8 localizes to nucleoli. When co-expressed with UBQLN2, RTL8 promotes nuclear translocation of UBQLN2. RTL8 also facilitates UBQLN2's nuclear translocation during heat shock. UBQLN2 and RTL8 colocalize within ubiquitin-enriched subnuclear structures containing PQC components. The robust effect of RTL8 on the nuclear translocation and subnuclear localization of UBQLN2 does not extend to the other brain-expressed ubiquilins, UBQLN1 and UBQLN4. Moreover, compared to UBQLN1 and UBQLN4, UBQLN2 preferentially stabilizes RTL8 levels in human cell lines and in mouse brain, supporting functional heterogeneity among UBQLNs. As a novel UBQLN2 interactor that recruits UBQLN2 to specific nuclear compartments, RTL8 may regulate UBQLN2 function in nuclear protein quality control.
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Affiliation(s)
- Harihar Milaganur Mohan
- Department of Neurology, University of Michigan, Ann Arbor, MI, 48109-2200, USA.,Graduate Program in Cellular and Molecular Biology, University of Michigan, Ann Arbor, MI, 48109-2200, USA
| | | | - Amit Pithadia
- Department of Neurology, University of Michigan, Ann Arbor, MI, 48109-2200, USA
| | - Emily V Crowley
- Department of Neurology, University of Michigan, Ann Arbor, MI, 48109-2200, USA
| | - Regina Pacitto
- Department of Neurology, University of Michigan, Ann Arbor, MI, 48109-2200, USA
| | - Nathaniel Safren
- Department of Neurology, University of Michigan, Ann Arbor, MI, 48109-2200, USA.,Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, IL, 60611, USA
| | - Bryce Trotter
- Department of Neurology, University of Michigan, Ann Arbor, MI, 48109-2200, USA
| | - Chengxin Zhang
- Department of Computational Medicine and Bioinformatics, University of Michigan, Ann Arbor, MI, 48109-2200, USA
| | - Xiaogen Zhou
- Department of Computational Medicine and Bioinformatics, University of Michigan, Ann Arbor, MI, 48109-2200, USA
| | - Yang Zhang
- Department of Computational Medicine and Bioinformatics, University of Michigan, Ann Arbor, MI, 48109-2200, USA
| | - Venkatesha Basrur
- Department of Pathology, University of Michigan Medical School, Ann Arbor, MI, 48109, USA
| | - Henry L Paulson
- Department of Neurology, University of Michigan, Ann Arbor, MI, 48109-2200, USA. .,Michigan Neuroscience Institute, University of Michigan, Ann Arbor, MI, 48109-2200, USA.
| | - Lisa M Sharkey
- Department of Neurology, University of Michigan, Ann Arbor, MI, 48109-2200, USA. .,Michigan Neuroscience Institute, University of Michigan, Ann Arbor, MI, 48109-2200, USA.
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19
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Grese ZR, Bastos AC, Mamede LD, French RL, Miller TM, Ayala YM. Specific RNA interactions promote TDP-43 multivalent phase separation and maintain liquid properties. EMBO Rep 2021; 22:e53632. [PMID: 34787357 DOI: 10.15252/embr.202153632] [Citation(s) in RCA: 38] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2021] [Revised: 11/01/2021] [Accepted: 11/02/2021] [Indexed: 12/31/2022] Open
Abstract
TDP-43 is an RNA-binding protein that forms ribonucleoprotein condensates via liquid-liquid phase separation (LLPS) and regulates gene expression through specific RNA interactions. Loss of TDP-43 protein homeostasis and dysfunction are tied to neurodegenerative disorders, mainly amyotrophic lateral sclerosis (ALS) and frontotemporal dementia. Alterations of TDP-43 LLPS properties may be linked to protein aggregation. However, the mechanisms regulating TDP-43 LLPS are ill-defined, particularly how TDP-43 association with specific RNA targets regulates TDP-43 condensation remains unclear. We show that RNA binding strongly promotes TDP-43 LLPS through sequence-specific interactions. RNA-driven condensation increases with the number of adjacent TDP-43-binding sites and is also mediated by multivalent interactions involving the amino and carboxy-terminal TDP-43 domains. The physiological relevance of RNA-driven TDP-43 condensation is supported by similar observations in mammalian cellular lysate. Importantly, we find that TDP-43-RNA association maintains liquid-like properties of the condensates, which are disrupted in the presence of ALS-linked TDP-43 mutations. Altogether, RNA binding plays a central role in modulating TDP-43 condensation while maintaining protein solubility, and defects in this RNA-mediated activity may underpin TDP-43-associated pathogenesis.
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Affiliation(s)
- Zachary R Grese
- Edward Doisy Department of Biochemistry and Molecular Biology, Saint Louis University, St. Louis, MO, USA
| | - Alliny Cs Bastos
- Edward Doisy Department of Biochemistry and Molecular Biology, Saint Louis University, St. Louis, MO, USA
| | - Lohany D Mamede
- Edward Doisy Department of Biochemistry and Molecular Biology, Saint Louis University, St. Louis, MO, USA
| | - Rachel L French
- Edward Doisy Department of Biochemistry and Molecular Biology, Saint Louis University, St. Louis, MO, USA
| | - Timothy M Miller
- Department of Neurology, Washington University School of Medicine, St. Louis, MO, USA
| | - Yuna M Ayala
- Edward Doisy Department of Biochemistry and Molecular Biology, Saint Louis University, St. Louis, MO, USA
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20
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Nishimoto Y, Nakagawa S, Okano H. NEAT1 lncRNA and amyotrophic lateral sclerosis. Neurochem Int 2021; 150:105175. [PMID: 34481908 DOI: 10.1016/j.neuint.2021.105175] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2021] [Revised: 08/14/2021] [Accepted: 08/30/2021] [Indexed: 12/15/2022]
Abstract
Amyotrophic lateral sclerosis (ALS) is a representative neurological disease that is known to devastate entire motor neurons within a period of just a few years. Discoveries of the specific pathologies of relevant RNA-binding proteins, including TAR DNA-binding protein-43 (TDP-43) and fused in sarcoma/translocated in liposarcoma (FUS/TLS), and the causative genes of both familial and sporadic ALS have provided crucial information that could lead to a cure. In recent ALS research the GGGGCC-repeat expansion in the C9orf72 gene was identified as one of the most important pathological findings, suggesting the significance of both nuclear dysfunction due to dipeptide repeat proteins (DPRs) and RNA toxicity (such as pathological alterations of non-coding RNAs). In research on model animals carrying ALS-related molecules, the determination of whether a factor is protective or toxic has been controversial. Herein, we review the findings regarding NEAT1 RNA and C9orf72 GGGGCC repeats associated with ALS, from the viewpoint of conversion from the protective stage in the nucleus in early-phase ALS to late-phase induction of cell death. This review will provide insights for the development of RNA effectors as novel ALS treatments.
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Affiliation(s)
- Yoshinori Nishimoto
- Department of Neurology, Keio University School of Medicine, 35 Shinanomachi, Shinjuku, Tokyo, Japan; Department of Physiology, Keio University School of Medicine, 35 Shinanomachi, Shinjuku, Tokyo, Japan.
| | - Shinichi Nakagawa
- RNA Biology Laboratory, Faculty of Pharmaceutical Sciences, Hokkaido University, Sapporo, Japan
| | - Hideyuki Okano
- Department of Physiology, Keio University School of Medicine, 35 Shinanomachi, Shinjuku, Tokyo, Japan.
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21
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Portz B, Lee BL, Shorter J. FUS and TDP-43 Phases in Health and Disease. Trends Biochem Sci 2021; 46:550-563. [PMID: 33446423 PMCID: PMC8195841 DOI: 10.1016/j.tibs.2020.12.005] [Citation(s) in RCA: 128] [Impact Index Per Article: 42.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2020] [Revised: 11/24/2020] [Accepted: 12/08/2020] [Indexed: 12/14/2022]
Abstract
The distinct prion-like domains (PrLDs) of FUS and TDP-43, modulate phase transitions that result in condensates with a range of material states. These assemblies are implicated in both health and disease. In this review, we examine how sequence, structure, post-translational modifications, and RNA can affect the self-assembly of these RNA-binding proteins (RBPs). We discuss how our emerging understanding of FUS and TDP-43 liquid-liquid phase separation (LLPS) and aggregation, could be leveraged to design new therapies for neurodegenerative diseases such as amyotrophic lateral sclerosis (ALS), frontotemporal dementia (FTD), and limbic-predominant age-related TDP-43 encephalopathy (LATE).
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Affiliation(s)
- Bede Portz
- Department of Biochemistry and Biophysics, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Bo Lim Lee
- Department of Biochemistry and Biophysics, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA 19104, USA
| | - James Shorter
- Department of Biochemistry and Biophysics, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA 19104, USA.
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22
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Mechanisms of TDP-43 Proteinopathy Onset and Propagation. Int J Mol Sci 2021; 22:ijms22116004. [PMID: 34199367 PMCID: PMC8199531 DOI: 10.3390/ijms22116004] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2021] [Revised: 05/25/2021] [Accepted: 05/28/2021] [Indexed: 01/21/2023] Open
Abstract
TDP-43 is an RNA-binding protein that has been robustly linked to the pathogenesis of a number of neurodegenerative disorders, including amyotrophic lateral sclerosis and frontotemporal dementia. While mutations in the TARDBP gene that codes for the protein have been identified as causing disease in a small subset of patients, TDP-43 proteinopathy is present in the majority of cases regardless of mutation status. This raises key questions regarding the mechanisms by which TDP-43 proteinopathy arises and spreads throughout the central nervous system. Numerous studies have explored the role of a variety of cellular functions on the disease process, and nucleocytoplasmic transport, protein homeostasis, RNA interactions and cellular stress have all risen to the forefront as possible contributors to the initiation of TDP-43 pathogenesis. There is also a small but growing body of evidence suggesting that aggregation-prone TDP-43 can recruit physiological TDP-43, and be transmitted intercellularly, providing a mechanism whereby small-scale proteinopathy spreads from cell to cell, reflecting the spread of clinical symptoms observed in patients. This review will discuss the potential role of the aforementioned cellular functions in TDP-43 pathogenesis, and explore how aberrant pathology may spread, and result in a feed-forward cascade effect, leading to robust TDP-43 proteinopathy and disease.
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23
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Connecting the "dots": RNP granule network in health and disease. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2021; 1868:119058. [PMID: 33989700 DOI: 10.1016/j.bbamcr.2021.119058] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 01/17/2021] [Revised: 05/01/2021] [Accepted: 05/07/2021] [Indexed: 12/26/2022]
Abstract
All cells contain ribonucleoprotein (RNP) granules - large membraneless structures composed of RNA and proteins. Recent breakthroughs in RNP granule research have brought a new appreciation of their crucial role in organising virtually all cellular processes. Cells widely exploit the flexible, dynamic nature of RNP granules to adapt to a variety of functional states and the ever-changing environment. Constant exchange of molecules between the different RNP granules connects them into a network. This network controls basal cellular activities and is remodelled to enable efficient stress response. Alterations in RNP granule structure and regulation have been found to lead to fatal human diseases. The interconnectedness of RNP granules suggests that the RNP granule network as a whole becomes affected in disease states such as a representative neurodegenerative disease amyotrophic lateral sclerosis (ALS). In this review, we summarize available evidence on the communication between different RNP granules and on the RNP granule network disruption as a primary ALS pathomechanism.
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24
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Asakawa K, Handa H, Kawakami K. Multi-phaseted problems of TDP-43 in selective neuronal vulnerability in ALS. Cell Mol Life Sci 2021; 78:4453-4465. [PMID: 33709256 PMCID: PMC8195926 DOI: 10.1007/s00018-021-03792-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2020] [Revised: 02/03/2021] [Accepted: 02/18/2021] [Indexed: 10/28/2022]
Abstract
Transactive response DNA-binding protein 43 kDa (TDP-43) encoded by the TARDBP gene is an evolutionarily conserved heterogeneous nuclear ribonucleoprotein (hnRNP) that regulates multiple steps of RNA metabolism, and its cytoplasmic aggregation characterizes degenerating motor neurons in amyotrophic lateral sclerosis (ALS). In most ALS cases, cytoplasmic TDP-43 aggregation occurs in the absence of mutations in the coding sequence of TARDBP. Thus, a major challenge in ALS research is to understand the nature of pathological changes occurring in wild-type TDP-43 and to explore upstream events in intracellular and extracellular milieu that promote the pathological transition of TDP-43. Despite the inherent obstacles to analyzing TDP-43 dynamics in in vivo motor neurons due to their anatomical complexity and inaccessibility, recent studies using cellular and animal models have provided important mechanistic insights into potential links between TDP-43 and motor neuron vulnerability in ALS. This review is intended to provide an overview of the current literature on the function and regulation of TDP-43-containing RNP granules or membraneless organelles, as revealed by various models, and to discuss the potential mechanisms by which TDP-43 can cause selective vulnerability of motor neurons in ALS.
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Affiliation(s)
- Kazuhide Asakawa
- Department of Chemical Biology, Tokyo Medical University, Shinjuku-ku, Tokyo, 160-8402, Japan.
- Division of Molecular and Developmental Biology, National Institute of Genetics, 1111 Yata, Mishima, Shizuoka, 411-8540, Japan.
- Department of Genetics, Graduate University for Advanced Studies (SOKENDAI), 1111 Yata, Mishima, Shizuoka, 411-8540, Japan.
| | - Hiroshi Handa
- Department of Chemical Biology, Tokyo Medical University, Shinjuku-ku, Tokyo, 160-8402, Japan
| | - Koichi Kawakami
- Division of Molecular and Developmental Biology, National Institute of Genetics, 1111 Yata, Mishima, Shizuoka, 411-8540, Japan
- Department of Genetics, Graduate University for Advanced Studies (SOKENDAI), 1111 Yata, Mishima, Shizuoka, 411-8540, Japan
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25
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Glineburg MR, Zhang Y, Krans A, Tank EM, Barmada SJ, Todd PK. Enhanced detection of expanded repeat mRNA foci with hybridization chain reaction. Acta Neuropathol Commun 2021; 9:73. [PMID: 33892814 PMCID: PMC8063431 DOI: 10.1186/s40478-021-01169-8] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2021] [Accepted: 03/27/2021] [Indexed: 12/17/2022] Open
Abstract
Transcribed nucleotide repeat expansions form detectable RNA foci in patient cells that contribute to disease pathogenesis. The most widely used method for detecting RNA foci, fluorescence in situ hybridization (FISH), is powerful but can suffer from issues related to signal above background. Here we developed a repeat-specific form of hybridization chain reaction (R-HCR) as an alternative method for detection of repeat RNA foci in two neurodegenerative disorders: C9orf72 associated ALS and frontotemporal dementia (C9 ALS/FTD) and Fragile X-associated tremor/ataxia syndrome. R-HCR to both G4C2 and CGG repeats exhibited comparable specificity but > 40 × sensitivity compared to FISH, with better detection of both nuclear and cytoplasmic foci in human C9 ALS/FTD fibroblasts, patient iPSC derived neurons, and patient brain samples. Using R-HCR, we observed that integrated stress response (ISR) activation significantly increased the number of endogenous G4C2 repeat RNA foci and triggered their selective nuclear accumulation without evidence of stress granule co-localization in patient fibroblasts and patient derived neurons. These data suggest that R-HCR can be a useful tool for tracking the behavior of repeat expansion mRNA in C9 ALS/FTD and other repeat expansion disorders.
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26
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Ainslie A, Huiting W, Barazzuol L, Bergink S. Genome instability and loss of protein homeostasis: converging paths to neurodegeneration? Open Biol 2021; 11:200296. [PMID: 33878947 PMCID: PMC8059563 DOI: 10.1098/rsob.200296] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
Genome instability and loss of protein homeostasis are hallmark events of age-related diseases that include neurodegeneration. Several neurodegenerative diseases, such as Alzheimer's disease, Parkinson's disease, Huntington's disease and amyotrophic lateral sclerosis are characterized by protein aggregation, while an impaired DNA damage response (DDR) as in many genetic DNA repair disorders leads to pronounced neuropathological features. It remains unclear to what degree these cellular events interconnect with each other in the development of neurological diseases. This review highlights how the loss of protein homeostasis and genome instability influence one other. We will discuss studies that illustrate this connection. DNA damage contributes to many neurodegenerative diseases, as shown by an increased level of DNA damage in patients, possibly due to the effects of protein aggregates on chromatin, the sequestration of DNA repair proteins and novel putative DNA repair functions. Conversely, genome stability is also important for protein homeostasis. For example, gene copy number variations and the loss of key DDR components can lead to marked proteotoxic stress. An improved understanding of how protein homeostasis and genome stability are mechanistically connected is needed and promises to lead to the development of novel therapeutic interventions.
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Affiliation(s)
- Anna Ainslie
- Department of Biomedical Sciences of Cells and Systems, University Medical Center Groningen, University of Groningen, Antonius Deusinglaan 1, 9713 AV, Groningen, The Netherlands.,Department of Radiation Oncology, University Medical Center Groningen, University of Groningen, Antonius Deusinglaan 1, 9713 AV, Groningen, The Netherlands
| | - Wouter Huiting
- Department of Biomedical Sciences of Cells and Systems, University Medical Center Groningen, University of Groningen, Antonius Deusinglaan 1, 9713 AV, Groningen, The Netherlands
| | - Lara Barazzuol
- Department of Biomedical Sciences of Cells and Systems, University Medical Center Groningen, University of Groningen, Antonius Deusinglaan 1, 9713 AV, Groningen, The Netherlands.,Department of Radiation Oncology, University Medical Center Groningen, University of Groningen, Antonius Deusinglaan 1, 9713 AV, Groningen, The Netherlands
| | - Steven Bergink
- Department of Biomedical Sciences of Cells and Systems, University Medical Center Groningen, University of Groningen, Antonius Deusinglaan 1, 9713 AV, Groningen, The Netherlands
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27
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Hervás R, Oroz J. Mechanistic Insights into the Role of Molecular Chaperones in Protein Misfolding Diseases: From Molecular Recognition to Amyloid Disassembly. Int J Mol Sci 2020; 21:ijms21239186. [PMID: 33276458 PMCID: PMC7730194 DOI: 10.3390/ijms21239186] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2020] [Revised: 11/29/2020] [Accepted: 11/29/2020] [Indexed: 12/14/2022] Open
Abstract
Age-dependent alterations in the proteostasis network are crucial in the progress of prevalent neurodegenerative diseases, such as Alzheimer’s, Parkinson’s, or amyotrophic lateral sclerosis, which are characterized by the presence of insoluble protein deposits in degenerating neurons. Because molecular chaperones deter misfolded protein aggregation, regulate functional phase separation, and even dissolve noxious aggregates, they are considered major sentinels impeding the molecular processes that lead to cell damage in the course of these diseases. Indeed, members of the chaperome, such as molecular chaperones and co-chaperones, are increasingly recognized as therapeutic targets for the development of treatments against degenerative proteinopathies. Chaperones must recognize diverse toxic clients of different orders (soluble proteins, biomolecular condensates, organized protein aggregates). It is therefore critical to understand the basis of the selective chaperone recognition to discern the mechanisms of action of chaperones in protein conformational diseases. This review aimed to define the selective interplay between chaperones and toxic client proteins and the basis for the protective role of these interactions. The presence and availability of chaperone recognition motifs in soluble proteins and in insoluble aggregates, both functional and pathogenic, are discussed. Finally, the formation of aberrant (pro-toxic) chaperone complexes will also be disclosed.
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Affiliation(s)
- Rubén Hervás
- Stowers Institute for Medical Research, Kansas City, MO 64110, USA;
| | - Javier Oroz
- Rocasolano Institute for Physical Chemistry, Spanish National Research Council (IQFR-CSIC), Serrano 119, E-28006 Madrid, Spain
- Correspondence: ; Tel.: +34-915619400
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28
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Stress-Specific Spatiotemporal Responses of RNA-Binding Proteins in Human Stem-Cell-Derived Motor Neurons. Int J Mol Sci 2020; 21:ijms21218346. [PMID: 33172210 PMCID: PMC7664327 DOI: 10.3390/ijms21218346] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2020] [Revised: 10/29/2020] [Accepted: 11/04/2020] [Indexed: 12/11/2022] Open
Abstract
RNA-binding proteins (RBPs) have been shown to play a key role in the pathogenesis of a variety of neurodegenerative disorders. Amyotrophic lateral sclerosis (ALS) is an exemplar neurodegenerative disease characterised by rapid progression and relatively selective motor neuron loss. Nuclear-to-cytoplasmic mislocalisation and accumulation of RBPs have been identified as a pathological hallmark of the disease, yet the spatiotemporal responses of RBPs to different extrinsic stressors in human neurons remain incompletely understood. Here, we used healthy induced pluripotent stem cell (iPSC)-derived motor neurons to model how different types of cellular stress affect the nucleocytoplasmic localisation of key ALS-linked RBPs. We found that osmotic stress robustly induced nuclear loss of TDP-43, SPFQ, FUS, hnRNPA1 and hnRNPK, with characteristic changes in nucleocytoplasmic localisation in an RBP-dependent manner. Interestingly, we found that RBPs displayed stress-dependent characteristics, with unique responses to both heat and oxidative stress. Alongside nucleocytoplasmic protein distribution changes, we identified the formation of stress- and RBP-specific nuclear and cytoplasmic foci. Furthermore, the kinetics of nuclear relocalisation upon recovery from extrinsic stressors was also found to be both stress- and RBP-specific. Importantly, these experiments specifically highlight TDP-43 and FUS, two of the most recognised RBPs in ALS pathogenesis, as exhibiting delayed nuclear relocalisation following stress in healthy human motor neurons as compared to SFPQ, hnRNPA1 and hnRNPK. Notably, ALS-causing valosin containing protein (VCP) mutations did not disrupt the relocalisation dynamics of TDP-43 or FUS in human motor neurons following stress. An increased duration of TDP-43 and FUS within the cytoplasm after stress may render the environment more aggregation-prone, which may be poorly tolerated in the context of ALS and related neurodegenerative disorders. In summary, our study addresses stress-specific spatiotemporal responses of neurodegeneration-related RBPs in human motor neurons. The insights into the nucleocytoplasmic dynamics of RBPs provided here may be informative for future studies examining both disease mechanisms and therapeutic strategy.
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29
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Jo M, Lee S, Jeon YM, Kim S, Kwon Y, Kim HJ. The role of TDP-43 propagation in neurodegenerative diseases: integrating insights from clinical and experimental studies. Exp Mol Med 2020; 52:1652-1662. [PMID: 33051572 PMCID: PMC8080625 DOI: 10.1038/s12276-020-00513-7] [Citation(s) in RCA: 126] [Impact Index Per Article: 31.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2020] [Revised: 08/21/2020] [Accepted: 08/26/2020] [Indexed: 12/11/2022] Open
Abstract
TAR DNA-binding protein 43 (TDP-43) is a highly conserved nuclear RNA/DNA-binding protein involved in the regulation of RNA processing. The accumulation of TDP-43 aggregates in the central nervous system is a common feature of many neurodegenerative diseases, such as amyotrophic lateral sclerosis (ALS), frontotemporal dementia (FTD), Alzheimer's disease (AD), and limbic predominant age-related TDP-43 encephalopathy (LATE). Accumulating evidence suggests that prion-like spreading of aberrant protein aggregates composed of tau, amyloid-β, and α-synuclein is involved in the progression of neurodegenerative diseases such as AD and PD. Similar to those of prion-like proteins, pathological aggregates of TDP-43 can be transferred from cell-to-cell in a seed-dependent and self-templating manner. Here, we review clinical and experimental studies supporting the prion-like spreading of misfolded TDP-43 and discuss the molecular mechanisms underlying the propagation of these pathological aggregated proteins. The idea that misfolded TDP-43 spreads in a prion-like manner between cells may guide novel therapeutic strategies for TDP-43-associated neurodegenerative diseases.
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Affiliation(s)
- Myungjin Jo
- Dementia Research Group, Korea Brain Research Institute (KBRI), Daegu, 41062, South Korea
| | - Shinrye Lee
- Dementia Research Group, Korea Brain Research Institute (KBRI), Daegu, 41062, South Korea
| | - Yu-Mi Jeon
- Dementia Research Group, Korea Brain Research Institute (KBRI), Daegu, 41062, South Korea
| | - Seyeon Kim
- Dementia Research Group, Korea Brain Research Institute (KBRI), Daegu, 41062, South Korea.,Department of Brain & Cognitive Sciences, DGIST, Daegu, 42988, South Korea
| | - Younghwi Kwon
- Dementia Research Group, Korea Brain Research Institute (KBRI), Daegu, 41062, South Korea.,Department of Brain & Cognitive Sciences, DGIST, Daegu, 42988, South Korea
| | - Hyung-Jun Kim
- Dementia Research Group, Korea Brain Research Institute (KBRI), Daegu, 41062, South Korea.
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30
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Tittelmeier J, Nachman E, Nussbaum-Krammer C. Molecular Chaperones: A Double-Edged Sword in Neurodegenerative Diseases. Front Aging Neurosci 2020; 12:581374. [PMID: 33132902 PMCID: PMC7572858 DOI: 10.3389/fnagi.2020.581374] [Citation(s) in RCA: 48] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2020] [Accepted: 09/09/2020] [Indexed: 12/16/2022] Open
Abstract
Aberrant accumulation of misfolded proteins into amyloid deposits is a hallmark in many age-related neurodegenerative diseases, including Alzheimer’s disease (AD), Parkinson’s disease (PD), Huntington’s disease (HD), and amyotrophic lateral sclerosis (ALS). Pathological inclusions and the associated toxicity appear to spread through the nervous system in a characteristic pattern during the disease. This has been attributed to a prion-like behavior of amyloid-type aggregates, which involves self-replication of the pathological conformation, intercellular transfer, and the subsequent seeding of native forms of the same protein in the neighboring cell. Molecular chaperones play a major role in maintaining cellular proteostasis by assisting the (re)-folding of cellular proteins to ensure their function or by promoting the degradation of terminally misfolded proteins to prevent damage. With increasing age, however, the capacity of this proteostasis network tends to decrease, which enables the manifestation of neurodegenerative diseases. Recently, there has been a plethora of studies investigating how and when chaperones interact with disease-related proteins, which have advanced our understanding of the role of chaperones in protein misfolding diseases. This review article focuses on the steps of prion-like propagation from initial misfolding and self-templated replication to intercellular spreading and discusses the influence that chaperones have on these various steps, highlighting both the positive and adverse consequences chaperone action can have. Understanding how chaperones alleviate and aggravate disease progression is vital for the development of therapeutic strategies to combat these debilitating diseases.
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Affiliation(s)
- Jessica Tittelmeier
- German Cancer Research Center (DKFZ), Center for Molecular Biology of Heidelberg University (ZMBH), DKFZ-ZMBH Alliance, Heidelberg, Germany
| | - Eliana Nachman
- German Cancer Research Center (DKFZ), Center for Molecular Biology of Heidelberg University (ZMBH), DKFZ-ZMBH Alliance, Heidelberg, Germany
| | - Carmen Nussbaum-Krammer
- German Cancer Research Center (DKFZ), Center for Molecular Biology of Heidelberg University (ZMBH), DKFZ-ZMBH Alliance, Heidelberg, Germany
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31
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Abstract
In this issue of Molecular Cell, Wang et al. (2020) investigate stress-induced nuclear condensates of the RNA-binding protein TDP-43, uncovering a protective function for these granules as well as an RNA-dependent mechanism for scaffolding them.
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32
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Wang C, Duan Y, Duan G, Wang Q, Zhang K, Deng X, Qian B, Gu J, Ma Z, Zhang S, Guo L, Liu C, Fang Y. Stress Induces Dynamic, Cytotoxicity-Antagonizing TDP-43 Nuclear Bodies via Paraspeckle LncRNA NEAT1-Mediated Liquid-Liquid Phase Separation. Mol Cell 2020; 79:443-458.e7. [PMID: 32649883 DOI: 10.1016/j.molcel.2020.06.019] [Citation(s) in RCA: 101] [Impact Index Per Article: 25.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2019] [Revised: 05/01/2020] [Accepted: 06/09/2020] [Indexed: 12/13/2022]
Abstract
Despite the prominent role of TDP-43 in neurodegeneration, its physiological and pathological functions are not fully understood. Here, we report an unexpected role of TDP-43 in the formation of dynamic, reversible, liquid droplet-like nuclear bodies (NBs) in response to stress. Formation of NBs alleviates TDP-43-mediated cytotoxicity in mammalian cells and fly neurons. Super-resolution microscopy reveals distinct functions of the two RRMs in TDP-43 NB formation. TDP-43 NBs are partially colocalized with nuclear paraspeckles, whose scaffolding lncRNA NEAT1 is dramatically upregulated in stressed neurons. Moreover, increase of NEAT1 promotes TDP-43 liquid-liquid phase separation (LLPS) in vitro. Finally, we discover that the ALS-associated mutation D169G impairs the NEAT1-mediated TDP-43 LLPS and NB assembly, causing excessive cytoplasmic translocation of TDP-43 to form stress granules, which become phosphorylated TDP-43 cytoplasmic foci upon prolonged stress. Together, our findings suggest a stress-mitigating role and mechanism of TDP-43 NBs, whose dysfunction may be involved in ALS pathogenesis.
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Affiliation(s)
- Chen Wang
- Interdisciplinary Research Center on Biology and Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, Shanghai 201210, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yongjia Duan
- Interdisciplinary Research Center on Biology and Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, Shanghai 201210, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Gang Duan
- Interdisciplinary Research Center on Biology and Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, Shanghai 201210, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Qiangqiang Wang
- Interdisciplinary Research Center on Biology and Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, Shanghai 201210, China
| | - Kai Zhang
- Interdisciplinary Research Center on Biology and Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, Shanghai 201210, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Xue Deng
- Interdisciplinary Research Center on Biology and Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, Shanghai 201210, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Beituo Qian
- Interdisciplinary Research Center on Biology and Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, Shanghai 201210, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Jinge Gu
- Interdisciplinary Research Center on Biology and Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, Shanghai 201210, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Zhiwei Ma
- Interdisciplinary Research Center on Biology and Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, Shanghai 201210, China
| | - Shuang Zhang
- Interdisciplinary Research Center on Biology and Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, Shanghai 201210, China
| | - Lin Guo
- Department of Biochemistry and Molecular Biology, Thomas Jefferson University, Philadelphia, PA 19107, USA
| | - Cong Liu
- Interdisciplinary Research Center on Biology and Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, Shanghai 201210, China; University of Chinese Academy of Sciences, Beijing 100049, China.
| | - Yanshan Fang
- Interdisciplinary Research Center on Biology and Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, Shanghai 201210, China; University of Chinese Academy of Sciences, Beijing 100049, China.
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33
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Besnard-Guérin C. Cytoplasmic localization of amyotrophic lateral sclerosis-related TDP-43 proteins modulates stress granule formation. Eur J Neurosci 2020; 52:3995-4008. [PMID: 32343854 DOI: 10.1111/ejn.14762] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2019] [Revised: 04/08/2020] [Accepted: 04/21/2020] [Indexed: 12/12/2022]
Abstract
TDP-43 is an RNA/DNA-binding protein associated with amyotrophic lateral sclerosis (ALS). Under pathological conditions, TDP-43 exported from the nucleus accumulates in the cytoplasm, forming inclusion bodies. However, the molecular mechanisms that contribute to such aggregation are unclear. The pathogenic processes that lead to aggregation in ALS were investigated by analysing the effects of wildtype human TDP-43 or with mutations in the nuclear localization sequence (NLS) or those associated with ALS in stress granule formation. TDP-43 (WT, ∆NLS or G348C), with or without a GFP-tag, was expressed in SH-SY5Y neuroblastoma or HeLa cells and stress granules induced by oxidative stress or heat shock. Stress granule formation was altered in cells strongly expressing GFP-TDP-∆NLS, or untagged TDP-43-∆NLS in the cytoplasm but not the negative controls, GFP or GFP-UtrCH. In contrast, there was no reduction in stress granule formation by cells that expressed untagged TDP-43 (WT or G348C) in the nucleus upon stress induction. GFP labelling of TDP-43 (WT or G348C) promotes high cytoplasmic expression and nuclear aggregation. Stress granule formation was impaired in cells expressing GFP-TDP-43 (WT or G348C) in the cytoplasm. Overall, these results suggest that stress granule formation may be inhibited by high levels of TDP-43 protein in the cytoplasm. As stress granules serve a protective function, their deregulation may promote neurodegeneration due to an aberrant stress response.
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Affiliation(s)
- Corinne Besnard-Guérin
- Sorbonne Université, Université Pierre et Marie Curie (UPMC), Université de Paris 06, Unité Mixte 75, Institut National de la Santé et de la Recherche Médicale (INSERM) Unité 1127, Centre National de la Recherche Scientifique (CNRS), Unité Mixte de Recherche 7225, Institut du Cerveau et de la Moelle Épinière (ICM), Paris, France
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34
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Neuromuscular Diseases Due to Chaperone Mutations: A Review and Some New Results. Int J Mol Sci 2020; 21:ijms21041409. [PMID: 32093037 PMCID: PMC7073051 DOI: 10.3390/ijms21041409] [Citation(s) in RCA: 40] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2020] [Revised: 02/12/2020] [Accepted: 02/13/2020] [Indexed: 12/12/2022] Open
Abstract
Skeletal muscle and the nervous system depend on efficient protein quality control, and they express chaperones and cochaperones at high levels to maintain protein homeostasis. Mutations in many of these proteins cause neuromuscular diseases, myopathies, and hereditary motor and sensorimotor neuropathies. In this review, we cover mutations in DNAJB6, DNAJB2, αB-crystallin (CRYAB, HSPB5), HSPB1, HSPB3, HSPB8, and BAG3, and discuss the molecular mechanisms by which they cause neuromuscular disease. In addition, previously unpublished results are presented, showing downstream effects of BAG3 p.P209L on DNAJB6 turnover and localization.
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35
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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: 64] [Impact Index Per Article: 12.8] [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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36
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Farhan SMK, Howrigan DP, Abbott LE, Klim JR, Topp SD, Byrnes AE, Churchhouse C, Phatnani H, Smith BN, Rampersaud E, Wu G, Wuu J, Shatunov A, Iacoangeli A, Al Khleifat A, Mordes DA, Ghosh S, Eggan K, Rademakers R, McCauley JL, Schüle R, Züchner S, Benatar M, Taylor JP, Nalls M, Gotkine M, Shaw PJ, Morrison KE, Al-Chalabi A, Traynor B, Shaw CE, Goldstein DB, Harms MB, Daly MJ, Neale BM. Exome sequencing in amyotrophic lateral sclerosis implicates a novel gene, DNAJC7, encoding a heat-shock protein. Nat Neurosci 2019; 22:1966-1974. [PMID: 31768050 PMCID: PMC6919277 DOI: 10.1038/s41593-019-0530-0] [Citation(s) in RCA: 81] [Impact Index Per Article: 16.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2019] [Accepted: 10/02/2019] [Indexed: 12/11/2022]
Abstract
To discover novel genes underlying amyotrophic lateral sclerosis (ALS), we aggregated exomes from 3,864 cases and 7,839 ancestry-matched controls. We observed a significant excess of rare protein-truncating variants among ALS cases, and these variants were concentrated in constrained genes. Through gene level analyses, we replicated known ALS genes including SOD1, NEK1 and FUS. We also observed multiple distinct protein-truncating variants in a highly constrained gene, DNAJC7. The signal in DNAJC7 exceeded genome-wide significance, and immunoblotting assays showed depletion of DNAJC7 protein in fibroblasts in a patient with ALS carrying the p.Arg156Ter variant. DNAJC7 encodes a member of the heat-shock protein family, HSP40, which, along with HSP70 proteins, facilitates protein homeostasis, including folding of newly synthesized polypeptides and clearance of degraded proteins. When these processes are not regulated, misfolding and accumulation of aberrant proteins can occur and lead to protein aggregation, which is a pathological hallmark of neurodegeneration. Our results highlight DNAJC7 as a novel gene for ALS.
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Affiliation(s)
- Sali M K Farhan
- Analytic and Translational Genetics Unit, Department of Medicine, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA.
- Program in Medical and Population Genetics, Broad Institute of Harvard and MIT, Cambridge, MA, USA.
- Stanley Center for Psychiatric Research, Broad Institute of Harvard and MIT, Cambridge, MA, USA.
| | - Daniel P Howrigan
- Analytic and Translational Genetics Unit, Department of Medicine, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA
- Program in Medical and Population Genetics, Broad Institute of Harvard and MIT, Cambridge, MA, USA
- Stanley Center for Psychiatric Research, Broad Institute of Harvard and MIT, Cambridge, MA, USA
| | - Liam E Abbott
- Analytic and Translational Genetics Unit, Department of Medicine, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA
- Program in Medical and Population Genetics, Broad Institute of Harvard and MIT, Cambridge, MA, USA
- Stanley Center for Psychiatric Research, Broad Institute of Harvard and MIT, Cambridge, MA, USA
| | - Joseph R Klim
- Department of Stem Cell and Regenerative Biology, Harvard Stem Cell Institute, Harvard University, Cambridge, MA, USA
| | - Simon D Topp
- United Kingdom Dementia Research Institute Centre, Maurice Wohl Clinical Neuroscience Institute, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK
| | - Andrea E Byrnes
- Analytic and Translational Genetics Unit, Department of Medicine, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA
- Program in Medical and Population Genetics, Broad Institute of Harvard and MIT, Cambridge, MA, USA
- Stanley Center for Psychiatric Research, Broad Institute of Harvard and MIT, Cambridge, MA, USA
| | - Claire Churchhouse
- Analytic and Translational Genetics Unit, Department of Medicine, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA
- Program in Medical and Population Genetics, Broad Institute of Harvard and MIT, Cambridge, MA, USA
- Stanley Center for Psychiatric Research, Broad Institute of Harvard and MIT, Cambridge, MA, USA
| | - Hemali Phatnani
- Center for Genomics of Neurodegenerative Disease, New York Genome Center, New York, NY, USA
| | - Bradley N Smith
- United Kingdom Dementia Research Institute Centre, Maurice Wohl Clinical Neuroscience Institute, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK
| | - Evadnie Rampersaud
- Department of Computational Biology, St. Jude Children's Research Hospital, Memphis, TN, USA
| | - Gang Wu
- Department of Computational Biology, St. Jude Children's Research Hospital, Memphis, TN, USA
| | - Joanne Wuu
- Department of Neurology, University of Miami, Miami, FL, USA
| | - Aleksey Shatunov
- Department of Basic and Clinical Neuroscience, Maurice Wohl Clinical Neuroscience Institute, King's College London, London, UK
| | - Alfredo Iacoangeli
- Department of Basic and Clinical Neuroscience, Maurice Wohl Clinical Neuroscience Institute, King's College London, London, UK
- Department of Biostatistics and Health Informatics, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK
| | - Ahmad Al Khleifat
- Department of Basic and Clinical Neuroscience, Maurice Wohl Clinical Neuroscience Institute, King's College London, London, UK
| | - Daniel A Mordes
- Department of Stem Cell and Regenerative Biology, Harvard Stem Cell Institute, Harvard University, Cambridge, MA, USA
| | - Sulagna Ghosh
- Stanley Center for Psychiatric Research, Broad Institute of Harvard and MIT, Cambridge, MA, USA
- Department of Stem Cell and Regenerative Biology, Harvard Stem Cell Institute, Harvard University, Cambridge, MA, USA
| | - Kevin Eggan
- Stanley Center for Psychiatric Research, Broad Institute of Harvard and MIT, Cambridge, MA, USA
- Department of Stem Cell and Regenerative Biology, Harvard Stem Cell Institute, Harvard University, Cambridge, MA, USA
| | - Rosa Rademakers
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL, USA
| | - Jacob L McCauley
- John P. Hussman Institute for Human Genomics, University of Miami, Miller School of Medicine, Miami, FL, USA
- The Dr. John T. Macdonald Foundation Department of Human Genetics, University of Miami, Miller School of Medicine, Miami, FL, USA
| | - Rebecca Schüle
- Center for Neurology and Hertie Institute für Clinical Brain Research, University of Tübingen, German Center for Neurodegenerative Diseases, Tübingen, Germany
| | - Stephan Züchner
- John P. Hussman Institute for Human Genomics, University of Miami, Miller School of Medicine, Miami, FL, USA
- The Dr. John T. Macdonald Foundation Department of Human Genetics, University of Miami, Miller School of Medicine, Miami, FL, USA
| | - Michael Benatar
- Department of Neurology, University of Miami, Miami, FL, USA
| | - J Paul Taylor
- Howard Hughes Medical Institute, Chevy Chase, MD, USA
- Department of Cell and Molecular Biology, St. Jude Children's Research Hospital, Memphis, TN, USA
| | - Michael Nalls
- Molecular Genetics Section, Laboratory of Neurogenetics, National Institute on Aging, Bethesda, MD, USA
- Data Tecnica International, Glen Echo, MD, USA
| | - Marc Gotkine
- Department of Neurology, The Agnes Ginges Center for Human Neurogenetics, Hadassah-Hebrew University Medical Center, Jerusalem, Israel
| | - Pamela J Shaw
- Sheffield Institute for Translational Neuroscience (SITraN), University of Sheffield, Sheffield, UK
| | - Karen E Morrison
- Faculty of Medicine, University of Southampton and Department of Neurology, University Hospital Southampton, Southampton, UK
| | - Ammar Al-Chalabi
- Department of Basic and Clinical Neuroscience, Maurice Wohl Clinical Neuroscience Institute, King's College London, London, UK
- Department of Neurology, King's College Hospital, London, UK
| | - Bryan Traynor
- Molecular Genetics Section, Laboratory of Neurogenetics, National Institute on Aging, Bethesda, MD, USA
- Department of Neurology, Johns Hopkins University, Baltimore, MD, USA
| | - Christopher E Shaw
- United Kingdom Dementia Research Institute Centre, Maurice Wohl Clinical Neuroscience Institute, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK
- Centre for Brain Research, University of Auckland, Auckland, New Zealand
| | - David B Goldstein
- Institute for Genomic Medicine, Columbia University, New York, NY, USA
| | - Matthew B Harms
- Department of Neurology, Columbia University, New York, NY, USA
| | - Mark J Daly
- Analytic and Translational Genetics Unit, Department of Medicine, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA
- Program in Medical and Population Genetics, Broad Institute of Harvard and MIT, Cambridge, MA, USA
- Stanley Center for Psychiatric Research, Broad Institute of Harvard and MIT, Cambridge, MA, USA
| | - Benjamin M Neale
- Analytic and Translational Genetics Unit, Department of Medicine, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA.
- Program in Medical and Population Genetics, Broad Institute of Harvard and MIT, Cambridge, MA, USA.
- Stanley Center for Psychiatric Research, Broad Institute of Harvard and MIT, Cambridge, MA, USA.
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Palmio J, Jonson PH, Inoue M, Sarparanta J, Bengoechea R, Savarese M, Vihola A, Jokela M, Nakagawa M, Noguchi S, Olivé M, Masingue M, Kerty E, Hackman P, Weihl CC, Nishino I, Udd B. Mutations in the J domain of DNAJB6 cause dominant distal myopathy. Neuromuscul Disord 2019; 30:38-46. [PMID: 31955980 DOI: 10.1016/j.nmd.2019.11.005] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2019] [Revised: 11/13/2019] [Accepted: 11/15/2019] [Indexed: 01/28/2023]
Abstract
Eight patients from five families with undiagnosed dominant distal myopathy underwent clinical, neurophysiological and muscle biopsy examinations. Molecular genetic studies were performed using targeted sequencing of all known myopathy genes followed by segregation of the identified mutations in the affected families using Sanger sequencing. Two novel mutations in DNAJB6 J domain, c.149C>T (p.A50V) and c.161A>C (p.E54A), were identified as the cause of disease. The muscle involvement with p.A50V was distal calf-predominant, and the p.E54A was more proximo-distal. Histological findings were similar to those previously reported in DNAJB6 myopathy. In line with reported pathogenic mutations in the glycine/phenylalanine (G/F) domain of DNAJB6, both the novel mutations showed reduced anti-aggregation capacity by filter trap assay and TDP-43 disaggregation assays. Modeling of the protein showed close proximity of the mutated residues with the G/F domain. Myopathy-causing mutations in DNAJB6 are not only located in the G/F domain, but also in the J domain. The identified mutations in the J domain cause dominant distal and proximo-distal myopathy, confirming that mutations in DNAJB6 should be considered in distal myopathy cases.
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Affiliation(s)
- Johanna Palmio
- Neuromuscular Research Center, Tampere University Hospital and Tampere University, P.O. box 100, FIN-33014 Tampere, Finland.
| | - Per Harald Jonson
- Folkhälsan Research Center, Helsinki, Finland and University of Helsinki, Medicum, Helsinki, Finland
| | - Michio Inoue
- National Center of Neurology and Psychiatry (NCNP), Department of Neuromuscular Research, National Institute of Neuroscience, Tokyo, Japan
| | - Jaakko Sarparanta
- Folkhälsan Research Center, Helsinki, Finland and University of Helsinki, Medicum, Helsinki, Finland
| | - Rocio Bengoechea
- Department of Neurology, Washington University in St. Louis, St. Louis, MO, USA
| | - Marco Savarese
- Folkhälsan Research Center, Helsinki, Finland and University of Helsinki, Medicum, Helsinki, Finland
| | - Anna Vihola
- Neuromuscular Research Center, Tampere University Hospital and Tampere University, P.O. box 100, FIN-33014 Tampere, Finland; Folkhälsan Research Center, Helsinki, Finland and University of Helsinki, Medicum, Helsinki, Finland
| | - Manu Jokela
- Neuromuscular Research Center, Tampere University Hospital and Tampere University, P.O. box 100, FIN-33014 Tampere, Finland; Division of Clinical Neurosciences, Turku University Hospital and University of Turku, Turku, Finland
| | - Masanori Nakagawa
- North Medical Center, Kyoto Prefectural University of Medicine, Kyoto, Japan
| | - Satoru Noguchi
- National Center of Neurology and Psychiatry (NCNP), Department of Neuromuscular Research, National Institute of Neuroscience, Tokyo, Japan
| | - Montse Olivé
- Department of Pathology and Neuromuscular Unit, IDIBELL-Hospital de Bellvitge, Barcelona, Spain
| | - Marion Masingue
- University Hospital of Salpêtrière, UPMC, Institute of Myology, National Reference Center for Neuromuscular Disorders, Paris, France
| | - Emilia Kerty
- Department of Neurology, Oslo University Hospital, Rikshospitalet, University of Oslo, Oslo, Norway
| | - Peter Hackman
- Folkhälsan Research Center, Helsinki, Finland and University of Helsinki, Medicum, Helsinki, Finland
| | - Conrad C Weihl
- Department of Neurology, Washington University in St. Louis, St. Louis, MO, USA
| | - Ichizo Nishino
- National Center of Neurology and Psychiatry (NCNP), Department of Neuromuscular Research, National Institute of Neuroscience, Tokyo, Japan
| | - Bjarne Udd
- Neuromuscular Research Center, Tampere University Hospital and Tampere University, P.O. box 100, FIN-33014 Tampere, Finland; Folkhälsan Research Center, Helsinki, Finland and University of Helsinki, Medicum, Helsinki, Finland
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French RL, Grese ZR, Aligireddy H, Dhavale DD, Reeb AN, Kedia N, Kotzbauer PT, Bieschke J, Ayala YM. Detection of TAR DNA-binding protein 43 (TDP-43) oligomers as initial intermediate species during aggregate formation. J Biol Chem 2019; 294:6696-6709. [PMID: 30824544 PMCID: PMC6497947 DOI: 10.1074/jbc.ra118.005889] [Citation(s) in RCA: 72] [Impact Index Per Article: 14.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2018] [Revised: 02/27/2019] [Indexed: 12/14/2022] Open
Abstract
Aggregates of the RNA-binding protein TDP-43 (TAR DNA-binding protein) are a hallmark of the overlapping neurodegenerative disorders amyotrophic lateral sclerosis (ALS) and frontotemporal dementia. The process of TDP-43 aggregation remains poorly understood, and whether it includes formation of intermediate complexes is unknown. Here, we analyzed aggregates derived from purified TDP-43 under semidenaturing conditions, identifying distinct oligomeric complexes at the initial time points before the formation of large aggregates. We found that this early oligomerization stage is primarily driven by TDP-43's RNA-binding region. Specific binding to GU-rich RNA strongly inhibited both TDP-43 oligomerization and aggregation, suggesting that RNA interactions are critical for maintaining TDP-43 solubility. Moreover, we analyzed TDP-43 liquid-liquid phase separation and detected similar detergent-resistant oligomers upon maturation of liquid droplets into solid-like fibrils. These results strongly suggest that the oligomers form during the early steps of TDP-43 misfolding. Importantly, the ALS-linked TDP-43 mutations A315T and M337V significantly accelerate aggregation, rapidly decreasing the monomeric population and shortening the oligomeric phase. We also show that aggregates generated from purified TDP-43 seed intracellular aggregation detected by established TDP-43 pathology markers. Remarkably, cytoplasmic aggregate seeding was detected earlier for the A315T and M337V variants and was 50% more widespread than for WT TDP-43 aggregates. We provide evidence for an initial step of TDP-43 self-assembly into intermediate oligomeric complexes, whereby these complexes may provide a scaffold for aggregation. This process is altered by ALS-linked mutations, underscoring the role of perturbations in TDP-43 homeostasis in protein aggregation and ALS-FTD pathogenesis.
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Affiliation(s)
- Rachel L French
- From the Edward A. Doisy Department of Biochemistry and Molecular Biology, Saint Louis University, St. Louis, Missouri 63103
| | - Zachary R Grese
- From the Edward A. Doisy Department of Biochemistry and Molecular Biology, Saint Louis University, St. Louis, Missouri 63103
| | - Himani Aligireddy
- From the Edward A. Doisy Department of Biochemistry and Molecular Biology, Saint Louis University, St. Louis, Missouri 63103
| | - Dhruva D Dhavale
- the Department of Neurology, Washington University School of Medicine, St. Louis, Missouri 63110, and
| | - Ashley N Reeb
- From the Edward A. Doisy Department of Biochemistry and Molecular Biology, Saint Louis University, St. Louis, Missouri 63103
| | - Niraja Kedia
- the MRC Prion Unit, University College London, London W1W 7FF, United Kingdom
| | - Paul T Kotzbauer
- the Department of Neurology, Washington University School of Medicine, St. Louis, Missouri 63110, and
| | - Jan Bieschke
- the MRC Prion Unit, University College London, London W1W 7FF, United Kingdom
| | - Yuna M Ayala
- From the Edward A. Doisy Department of Biochemistry and Molecular Biology, Saint Louis University, St. Louis, Missouri 63103,
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39
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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: 101] [Impact Index Per Article: 20.2] [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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40
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Prasad A, Bharathi V, Sivalingam V, Girdhar A, Patel BK. Molecular Mechanisms of TDP-43 Misfolding and Pathology in Amyotrophic Lateral Sclerosis. Front Mol Neurosci 2019; 12:25. [PMID: 30837838 PMCID: PMC6382748 DOI: 10.3389/fnmol.2019.00025] [Citation(s) in RCA: 400] [Impact Index Per Article: 80.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2018] [Accepted: 01/21/2019] [Indexed: 12/11/2022] Open
Abstract
TAR DNA binding protein 43 (TDP-43) is a versatile RNA/DNA binding protein involved in RNA-related metabolism. Hyper-phosphorylated and ubiquitinated TDP-43 deposits act as inclusion bodies in the brain and spinal cord of patients with the motor neuron diseases: amyotrophic lateral sclerosis (ALS) and frontotemporal lobar degeneration (FTLD). While the majority of ALS cases (90-95%) are sporadic (sALS), among familial ALS cases 5-10% involve the inheritance of mutations in the TARDBP gene and the remaining (90-95%) are due to mutations in other genes such as: C9ORF72, SOD1, FUS, and NEK1 etc. Strikingly however, the majority of sporadic ALS patients (up to 97%) also contain the TDP-43 protein deposited in the neuronal inclusions, which suggests of its pivotal role in the ALS pathology. Thus, unraveling the molecular mechanisms of the TDP-43 pathology seems central to the ALS therapeutics, hence, we comprehensively review the current understanding of the TDP-43's pathology in ALS. We discuss the roles of TDP-43's mutations, its cytoplasmic mis-localization and aberrant post-translational modifications in ALS. Also, we evaluate TDP-43's amyloid-like in vitro aggregation, its physiological vs. pathological oligomerization in vivo, liquid-liquid phase separation (LLPS), and potential prion-like propagation propensity of the TDP-43 inclusions. Finally, we describe the various evolving TDP-43-induced toxicity mechanisms, such as the impairment of endocytosis and mitotoxicity etc. and also discuss the emerging strategies toward TDP-43 disaggregation and ALS therapeutics.
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Affiliation(s)
| | | | | | | | - Basant K. Patel
- Department of Biotechnology, Indian Institute of Technology Hyderabad, Sangareddy, India
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41
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Proteomic analysis of protein homeostasis and aggregation. J Proteomics 2018; 198:98-112. [PMID: 30529741 DOI: 10.1016/j.jprot.2018.12.003] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2018] [Revised: 11/24/2018] [Accepted: 12/05/2018] [Indexed: 12/13/2022]
Abstract
Protein homeostasis (proteostasis) refers to the ability of cells to preserve the correct balance between protein synthesis, folding and degradation. Proteostasis is essential for optimal cell growth and survival under stressful conditions. Various extracellular and intracellular stresses including heat shock, oxidative stress, proteasome malfunction, mutations and aging-related modifications can result in disturbed proteostasis manifested by enhanced misfolding and aggregation of proteins. To limit protein misfolding and aggregation cells have evolved various strategies including molecular chaperones, proteasome system and autophagy. Molecular chaperones assist folding of proteins, protect them from denaturation and facilitate renaturation of the misfolded polypeptides, whereas proteasomes and autophagosomes remove the irreversibly damaged proteins. The impairment of proteostasis results in protein aggregation that is a major pathological hallmark of numerous age-related disorders, such as cataract, Alzheimer's, Parkinson's, Huntington's, and prion diseases. To discover protein markers and speed up diagnosis of neurodegenerative diseases accompanied by protein aggregation, proteomic tools have increasingly been used in recent years. Systematic and exhaustive analysis of the changes that occur in the proteomes of affected tissues and biofluids in humans or in model organisms is one of the most promising approaches to reveal mechanisms underlying protein aggregation diseases, improve their diagnosis and develop therapeutic strategies. Significance: In this review we outline the elements responsible for maintaining cellular proteostasis and present the overview of proteomic studies focused on protein-aggregation diseases. These studies provide insights into the mechanisms responsible for age-related disorders and reveal new potential biomarkers for Alzheimer's, Parkinson's, Huntigton's and prion diseases.
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42
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Goutman SA, Chen KS, Paez-Colasante X, Feldman EL. Emerging understanding of the genotype-phenotype relationship in amyotrophic lateral sclerosis. HANDBOOK OF CLINICAL NEUROLOGY 2018; 148:603-623. [PMID: 29478603 DOI: 10.1016/b978-0-444-64076-5.00039-9] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
Amyotrophic lateral sclerosis (ALS) is a progressive, noncurable neurodegenerative disorder of the upper and lower motor neurons causing weakness and death within a few years of symptom onset. About 10% of patients with ALS have a family history of the disease; however, ALS-associated genetic mutations are also found in sporadic cases. There are over 100 ALS-associated mutations, and importantly, several genetic mutations, including C9ORF72, SOD1, and TARDBP, have led to mechanistic insight into this complex disease. In the clinical realm, knowledge of ALS genetics can also help explain phenotypic heterogeneity, aid in genetic counseling, and in the future may help direct treatment efforts.
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Affiliation(s)
- Stephen A Goutman
- Department of Neurology, University of Michigan, Ann Arbor, MI, United States.
| | - Kevin S Chen
- Department of Neurosurgery, University of Michigan, Ann Arbor, MI, United States
| | | | - Eva L Feldman
- Department of Neurology, University of Michigan, Ann Arbor, MI, United States
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43
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Brehme M, Voisine C. Model systems of protein-misfolding diseases reveal chaperone modifiers of proteotoxicity. Dis Model Mech 2017; 9:823-38. [PMID: 27491084 PMCID: PMC5007983 DOI: 10.1242/dmm.024703] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
Chaperones and co-chaperones enable protein folding and degradation, safeguarding the proteome against proteotoxic stress. Chaperones display dynamic responses to exogenous and endogenous stressors and thus constitute a key component of the proteostasis network (PN), an intricately regulated network of quality control and repair pathways that cooperate to maintain cellular proteostasis. It has been hypothesized that aging leads to chronic stress on the proteome and that this could underlie many age-associated diseases such as neurodegeneration. Understanding the dynamics of chaperone function during aging and disease-related proteotoxic stress could reveal specific chaperone systems that fail to respond to protein misfolding. Through the use of suppressor and enhancer screens, key chaperones crucial for proteostasis maintenance have been identified in model organisms that express misfolded disease-related proteins. This review provides a literature-based analysis of these genetic studies and highlights prominent chaperone modifiers of proteotoxicity, which include the HSP70-HSP40 machine and small HSPs. Taken together, these studies in model systems can inform strategies for therapeutic regulation of chaperone functionality, to manage aging-related proteotoxic stress and to delay the onset of neurodegenerative diseases.
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Affiliation(s)
- Marc Brehme
- Joint Research Center for Computational Biomedicine (JRC-COMBINE), RWTH Aachen University, 52062 Aachen, Germany
| | - Cindy Voisine
- Department of Biology, Northeastern Illinois University, Chicago, IL 60625, USA
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Amanullah A, Upadhyay A, Joshi V, Mishra R, Jana NR, Mishra A. Progressing neurobiological strategies against proteostasis failure: Challenges in neurodegeneration. Prog Neurobiol 2017; 159:1-38. [DOI: 10.1016/j.pneurobio.2017.08.005] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2017] [Revised: 06/01/2017] [Accepted: 08/25/2017] [Indexed: 02/07/2023]
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45
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Clinical and biological phenotypes of frontotemporal dementia: Perspectives for disease modifying therapies. Eur J Pharmacol 2017; 817:76-85. [DOI: 10.1016/j.ejphar.2017.05.056] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2016] [Revised: 03/28/2017] [Accepted: 05/30/2017] [Indexed: 12/12/2022]
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46
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Wang P, Wander CM, Yuan CX, Bereman MS, Cohen TJ. Acetylation-induced TDP-43 pathology is suppressed by an HSF1-dependent chaperone program. Nat Commun 2017; 8:82. [PMID: 28724966 PMCID: PMC5517419 DOI: 10.1038/s41467-017-00088-4] [Citation(s) in RCA: 52] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2016] [Accepted: 05/31/2017] [Indexed: 12/12/2022] Open
Abstract
TDP-43 pathology marks a spectrum of multisystem proteinopathies including amyotrophic lateral sclerosis, frontotemporal lobar degeneration, and sporadic inclusion body myositis. Surprisingly, it has been challenging to recapitulate this pathology, highlighting an incomplete understanding of TDP-43 regulatory mechanisms. Here we provide evidence supporting TDP-43 acetylation as a trigger for disease pathology. Using cultured cells and mouse skeletal muscle, we show that TDP-43 acetylation-mimics promote TDP-43 phosphorylation and ubiquitination, perturb mitochondria, and initiate degenerative inflammatory responses that resemble sporadic inclusion body myositis pathology. Analysis of functionally linked amyotrophic lateral sclerosis proteins revealed recruitment of p62, ubiquilin-2, and optineurin to TDP-43 aggregates. We demonstrate that TDP-43 acetylation-mimic pathology is potently suppressed by an HSF1-dependent mechanism that disaggregates TDP-43. Our study illustrates bidirectional TDP-43 processing in which TDP-43 aggregation is targeted by a coordinated chaperone response. Thus, activation or restoration of refolding mechanisms may alleviate TDP-43 aggregation in tissues that are uniquely susceptible to TDP-43 proteinopathies. TDP-43 aggregation is linked to various diseases including amyotrophic lateral sclerosis. Here the authors show that acetylation of the protein triggers TDP-43 pathology in cultured cells and mouse skeletal muscle, which can be cleared through an HSF1-dependent chaperone mechanism that disaggregates the protein.
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Affiliation(s)
- Ping Wang
- Department of Neurology, UNC Neuroscience Center, University of North Carolina, Chapel Hill, NC, 27599, USA
| | - Connor M Wander
- Department of Neurology, UNC Neuroscience Center, University of North Carolina, Chapel Hill, NC, 27599, USA
| | | | - Michael S Bereman
- Department of Biological Sciences and Department of Chemistry, Center for Human Health and the Environment, North Carolina State University, Raleigh, NC, 27695, USA
| | - Todd J Cohen
- Department of Neurology, UNC Neuroscience Center, University of North Carolina, Chapel Hill, NC, 27599, USA.
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47
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Overexpression of the essential Sis1 chaperone reduces TDP-43 effects on toxicity and proteolysis. PLoS Genet 2017; 13:e1006805. [PMID: 28531192 PMCID: PMC5460882 DOI: 10.1371/journal.pgen.1006805] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2016] [Revised: 06/06/2017] [Accepted: 05/05/2017] [Indexed: 12/12/2022] Open
Abstract
Amyotrophic lateral sclerosis (ALS) is a devastating neurodegenerative disease characterized by selective loss of motor neurons with inclusions frequently containing the RNA/DNA binding protein TDP-43. Using a yeast model of ALS exhibiting TDP-43 dependent toxicity, we now show that TDP-43 overexpression dramatically alters cell shape and reduces ubiquitin dependent proteolysis of a reporter construct. Furthermore, we show that an excess of the Hsp40 chaperone, Sis1, reduced TDP-43’s effect on toxicity, cell shape and proteolysis. The strength of these effects was influenced by the presence of the endogenous yeast prion, [PIN+]. Although overexpression of Sis1 altered the TDP-43 aggregation pattern, we did not detect physical association of Sis1 with TDP-43, suggesting the possibility of indirect effects on TDP-43 aggregation. Furthermore, overexpression of the mammalian Sis1 homologue, DNAJB1, relieves TDP-43 mediated toxicity in primary rodent cortical neurons, suggesting that Sis1 and its homologues may have neuroprotective effects in ALS. Many neurodegenerative diseases are associated with aggregation of specific proteins. Thus we are interested in factors that influence the aggregation and how the aggregated proteins are associated with pathology. Here, we study a protein called TDP-43 that is frequently aggregated in the neurons of patients with amyotrophic lateral sclerosis (ALS). TDP-43 aggregates and is toxic when expressed in yeast, providing a useful model for ALS. Remarkably, a protein that modified TDP-43 toxicity in yeast successfully predicted a new ALS susceptibility gene in humans. We now report a new modifier of TDP-43 toxicity, Sis1. We show that expression of TDP-43 in yeast inhibits degradation of damaged protein, while overexpression of Sis1 restores degradation. Thus suggests a link between protein degradation and TDP-43 toxicity. Furthermore we show that a mammalian protein similar to Sis1 reduces TDP-43 toxicity in primary rodent neurons. This identifies the mammalian Sis1-like gene as a new ALS therapeutic target and possible susceptibility gene.
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48
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Lazarev VF, Mikhaylova ER, Guzhova IV, Margulis BA. Possible Function of Molecular Chaperones in Diseases Caused by Propagating Amyloid Aggregates. Front Neurosci 2017; 11:277. [PMID: 28559794 PMCID: PMC5433261 DOI: 10.3389/fnins.2017.00277] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2017] [Accepted: 04/30/2017] [Indexed: 12/14/2022] Open
Abstract
The vast majority of neurodegenerative pathologies stem from the formation of toxic oligomers and aggregates composed of wrongly folded proteins. These protein complexes can be released from pathogenic cells and enthralled by other cells, causing the formation of new aggregates in a prion-like manner. By this mechanism, migrating complexes can transmit a disorder to distant regions of the brain and promote gradually transmitting degenerative processes. Molecular chaperones can counteract the toxicity of misfolded proteins. In this review, we discuss recent data on the possible cytoprotective functions of chaperones in horizontally transmitting neurological disorders.
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Affiliation(s)
- Vladimir F Lazarev
- Laboratory of Cell Protection Mechanisms, Institute of Cytology of the Russian Academy of SciencesSt. Petersburg, Russia
| | - Elena R Mikhaylova
- Laboratory of Cell Protection Mechanisms, Institute of Cytology of the Russian Academy of SciencesSt. Petersburg, Russia
| | - Irina V Guzhova
- Laboratory of Cell Protection Mechanisms, Institute of Cytology of the Russian Academy of SciencesSt. Petersburg, Russia
| | - Boris A Margulis
- Laboratory of Cell Protection Mechanisms, Institute of Cytology of the Russian Academy of SciencesSt. Petersburg, Russia
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Lackie RE, Maciejewski A, Ostapchenko VG, Marques-Lopes J, Choy WY, Duennwald ML, Prado VF, Prado MAM. The Hsp70/Hsp90 Chaperone Machinery in Neurodegenerative Diseases. Front Neurosci 2017; 11:254. [PMID: 28559789 PMCID: PMC5433227 DOI: 10.3389/fnins.2017.00254] [Citation(s) in RCA: 232] [Impact Index Per Article: 33.1] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2017] [Accepted: 04/20/2017] [Indexed: 12/12/2022] Open
Abstract
The accumulation of misfolded proteins in the human brain is one of the critical features of many neurodegenerative diseases, including Alzheimer's disease (AD). Assembles of beta-amyloid (Aβ) peptide—either soluble (oligomers) or insoluble (plaques) and of tau protein, which form neurofibrillary tangles, are the major hallmarks of AD. Chaperones and co-chaperones regulate protein folding and client maturation, but they also target misfolded or aggregated proteins for refolding or for degradation, mostly by the proteasome. They form an important line of defense against misfolded proteins and are part of the cellular quality control system. The heat shock protein (Hsp) family, particularly Hsp70 and Hsp90, plays a major part in this process and it is well-known to regulate protein misfolding in a variety of diseases, including tau levels and toxicity in AD. However, the role of Hsp90 in regulating protein misfolding is not yet fully understood. For example, knockdown of Hsp90 and its co-chaperones in a Caenorhabditis elegans model of Aβ misfolding leads to increased toxicity. On the other hand, the use of Hsp90 inhibitors in AD mouse models reduces Aβ toxicity, and normalizes synaptic function. Stress-inducible phosphoprotein 1 (STI1), an intracellular co-chaperone, mediates the transfer of clients from Hsp70 to Hsp90. Importantly, STI1 has been shown to regulate aggregation of amyloid-like proteins in yeast. In addition to its intracellular function, STI1 can be secreted by diverse cell types, including astrocytes and microglia and function as a neurotrophic ligand by triggering signaling via the cellular prion protein (PrPC). Extracellular STI1 can prevent Aβ toxic signaling by (i) interfering with Aβ binding to PrPC and (ii) triggering pro-survival signaling cascades. Interestingly, decreased levels of STI1 in C. elegans can also increase toxicity in an amyloid model. In this review, we will discuss the role of intracellular and extracellular STI1 and the Hsp70/Hsp90 chaperone network in mechanisms underlying protein misfolding in neurodegenerative diseases, with particular focus on AD.
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Affiliation(s)
- Rachel E Lackie
- Molecular Medicine, Robarts Research Institute, University of Western OntarioLondon, ON, Canada.,Program in Neuroscience, University of Western OntarioLondon, ON, Canada
| | - Andrzej Maciejewski
- Molecular Medicine, Robarts Research Institute, University of Western OntarioLondon, ON, Canada.,Department of Biochemistry, University of Western OntarioLondon, ON, Canada
| | - Valeriy G Ostapchenko
- Molecular Medicine, Robarts Research Institute, University of Western OntarioLondon, ON, Canada
| | - Jose Marques-Lopes
- Molecular Medicine, Robarts Research Institute, University of Western OntarioLondon, ON, Canada
| | - Wing-Yiu Choy
- Department of Biochemistry, University of Western OntarioLondon, ON, Canada
| | - Martin L Duennwald
- Department of Pathology and Laboratory Medicine, University of Western OntarioLondon, ON, Canada
| | - Vania F Prado
- Molecular Medicine, Robarts Research Institute, University of Western OntarioLondon, ON, Canada.,Program in Neuroscience, University of Western OntarioLondon, ON, Canada.,Department of Physiology and Pharmacology, University of Western OntarioLondon, ON, Canada.,Department of Anatomy and Cell Biology, Schulich School of Medicine and Dentistry, University of Western OntarioLondon, ON, Canada
| | - Marco A M Prado
- Molecular Medicine, Robarts Research Institute, University of Western OntarioLondon, ON, Canada.,Program in Neuroscience, University of Western OntarioLondon, ON, Canada.,Department of Physiology and Pharmacology, University of Western OntarioLondon, ON, Canada.,Department of Anatomy and Cell Biology, Schulich School of Medicine and Dentistry, University of Western OntarioLondon, ON, Canada
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Kitamura A, Yuno S, Muto H, Kinjo M. Different aggregation states of a nuclear localization signal-tagged 25-kDa C-terminal fragment of TAR RNA/DNA-binding protein 43 kDa. Genes Cells 2017; 22:521-534. [PMID: 28497562 DOI: 10.1111/gtc.12495] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2016] [Accepted: 03/27/2017] [Indexed: 12/14/2022]
Abstract
The mechanism and cause of motor neuronal cell death in amyotrophic lateral sclerosis (ALS), a devastating neurodegenerative disorder, are unknown; gain of function of oligomers and aggregation of misfolded proteins, including carboxyl-terminal fragments (CTFs) of TAR RNA/DNA-binding protein 43 kDa (TDP-43), have been proposed as important causative factors in the onset of ALS. We recently reported that a nuclear localization signal (NLS)-tagged 25-kDa CTF of TDP-43 (TDP25) could decrease the cell-death proportion compared with that promoted by TDP25. Here, we show oligomeric states of NLS-TDP25 and its detailed localization property using super-resolution fluorescence microscopy, FRET, fluorescence recovery after photobleaching, and fluorescence correlation spectroscopy analysis. NLS-TDP25 efficiently formed a nucleolar cap structure via RNA binding in the presence of actinomycin D, but TDP25 did not. Although cytoplasmic inclusion bodies including TDP25 had a disordered and immobile structure, NLS-TDP25 in the nucleolus was ordered and dynamic. In the diffuse state, TDP25 formed fewer oligomers and interacted with the molecular chaperone, HSP70; however, NLS-TDP25 formed oligomers. These results suggested that NLS-tagged TDP25 can change its structure to use ordered oligomeric but nontoxic state. Moreover, the structure of ordered oligomers as well as nuclear sequestration may be important in mediating cytotoxicity in ALS pathology.
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Affiliation(s)
- Akira Kitamura
- Laboratory of Molecular Cell Dynamics, Faculty of Advanced Life Science, Hokkaido University, Sapporo, Japan
| | - Sachiko Yuno
- Laboratory of Molecular Cell Dynamics, Faculty of Advanced Life Science, Hokkaido University, Sapporo, Japan
| | - Hideki Muto
- Laboratory of Molecular Cell Dynamics, Faculty of Advanced Life Science, Hokkaido University, Sapporo, Japan
| | - Masataka Kinjo
- Laboratory of Molecular Cell Dynamics, Faculty of Advanced Life Science, Hokkaido University, Sapporo, Japan
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