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Fare CM, Rothstein JD. Nuclear pore dysfunction and disease: a complex opportunity. Nucleus 2024; 15:2314297. [PMID: 38383349 PMCID: PMC10883112 DOI: 10.1080/19491034.2024.2314297] [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: 11/27/2023] [Accepted: 01/30/2024] [Indexed: 02/23/2024] Open
Abstract
The separation of genetic material from bulk cytoplasm has enabled the evolution of increasingly complex organisms, allowing for the development of sophisticated forms of life. However, this complexity has created new categories of dysfunction, including those related to the movement of material between cellular compartments. In eukaryotic cells, nucleocytoplasmic trafficking is a fundamental biological process, and cumulative disruptions to nuclear integrity and nucleocytoplasmic transport are detrimental to cell survival. This is particularly true in post-mitotic neurons, where nuclear pore injury and errors to nucleocytoplasmic trafficking are strongly associated with neurodegenerative disease. In this review, we summarize the current understanding of nuclear pore biology in physiological and pathological contexts and discuss potential therapeutic approaches for addressing nuclear pore injury and dysfunctional nucleocytoplasmic transport.
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Affiliation(s)
- Charlotte M Fare
- Department of Neurology and Brain Science Institute, Johns Hopkins University, Baltimore, MD, USA
| | - Jeffrey D Rothstein
- Department of Neurology and Brain Science Institute, Johns Hopkins University, Baltimore, MD, USA
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2
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Cicardi ME, Kankate V, Sriramoji S, Krishnamurthy K, Markandaiah SS, Verdone BM, Girdhar A, Nelson A, Rivas LB, Boehringer A, Haeusler AR, Pasinelli P, Guo L, Trotti D. The nuclear import receptor Kapβ2 modifies neurotoxicity mediated by poly(GR) in C9orf72-linked ALS/FTD. Commun Biol 2024; 7:376. [PMID: 38548902 PMCID: PMC10978903 DOI: 10.1038/s42003-024-06071-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2023] [Accepted: 03/19/2024] [Indexed: 04/01/2024] Open
Abstract
Expanded intronic G4C2 repeats in the C9ORF72 gene cause amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD). These intronic repeats are translated through a non-AUG-dependent mechanism into five different dipeptide repeat proteins (DPRs), including poly-glycine-arginine (GR), which is aggregation-prone and neurotoxic. Here, we report that Kapβ2 and GR interact, co-aggregating, in cultured neurons in-vitro and CNS tissue in-vivo. Importantly, this interaction significantly decreased the risk of death of cultured GR-expressing neurons. Downregulation of Kapβ2 is detrimental to their survival, whereas increased Kapβ2 levels mitigated GR-mediated neurotoxicity. As expected, GR-expressing neurons displayed TDP-43 nuclear loss. Raising Kapβ2 levels did not restore TDP-43 into the nucleus, nor did alter the dynamic properties of GR aggregates. Overall, our findings support the design of therapeutic strategies aimed at up-regulating Kapβ2 expression levels as a potential new avenue for contrasting neurodegeneration in C9orf72-ALS/FTD.
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Affiliation(s)
- M E Cicardi
- Weinberg ALS Center, Vickie and Jack Farber Institute for Neuroscience, Department of Neuroscience, Thomas Jefferson University, Philadelphia, PA, USA
| | - V Kankate
- Weinberg ALS Center, Vickie and Jack Farber Institute for Neuroscience, Department of Neuroscience, Thomas Jefferson University, Philadelphia, PA, USA
| | - S Sriramoji
- Weinberg ALS Center, Vickie and Jack Farber Institute for Neuroscience, Department of Neuroscience, Thomas Jefferson University, Philadelphia, PA, USA
| | - K Krishnamurthy
- Weinberg ALS Center, Vickie and Jack Farber Institute for Neuroscience, Department of Neuroscience, Thomas Jefferson University, Philadelphia, PA, USA
| | - S S Markandaiah
- Weinberg ALS Center, Vickie and Jack Farber Institute for Neuroscience, Department of Neuroscience, Thomas Jefferson University, Philadelphia, PA, USA
| | - B M Verdone
- Weinberg ALS Center, Vickie and Jack Farber Institute for Neuroscience, Department of Neuroscience, Thomas Jefferson University, Philadelphia, PA, USA
| | - A Girdhar
- Department of Biochemistry and Molecular Biology, Thomas Jefferson University, Philadelphia, PA, USA
| | - A Nelson
- Weinberg ALS Center, Vickie and Jack Farber Institute for Neuroscience, Department of Neuroscience, Thomas Jefferson University, Philadelphia, PA, USA
| | - L B Rivas
- Weinberg ALS Center, Vickie and Jack Farber Institute for Neuroscience, Department of Neuroscience, Thomas Jefferson University, Philadelphia, PA, USA
| | - A Boehringer
- Weinberg ALS Center, Vickie and Jack Farber Institute for Neuroscience, Department of Neuroscience, Thomas Jefferson University, Philadelphia, PA, USA
| | - A R Haeusler
- Weinberg ALS Center, Vickie and Jack Farber Institute for Neuroscience, Department of Neuroscience, Thomas Jefferson University, Philadelphia, PA, USA
| | - P Pasinelli
- Weinberg ALS Center, Vickie and Jack Farber Institute for Neuroscience, Department of Neuroscience, Thomas Jefferson University, Philadelphia, PA, USA
| | - L Guo
- Department of Biochemistry and Molecular Biology, Thomas Jefferson University, Philadelphia, PA, USA.
| | - D Trotti
- Weinberg ALS Center, Vickie and Jack Farber Institute for Neuroscience, Department of Neuroscience, Thomas Jefferson University, Philadelphia, PA, USA.
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3
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Xiao C, Gu X, Feng Y, Shen J. Two-sample Mendelian randomization analysis of 91 circulating inflammatory protein levels and amyotrophic lateral sclerosis. Front Aging Neurosci 2024; 16:1367106. [PMID: 38601850 PMCID: PMC11004327 DOI: 10.3389/fnagi.2024.1367106] [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: 01/09/2024] [Accepted: 03/18/2024] [Indexed: 04/12/2024] Open
Abstract
Introduction Amyotrophic Lateral Sclerosis (ALS) is a neurodegenerative disease with poorly understood pathophysiology. Recent studies have highlighted systemic inflammation, especially the role of circulating inflammatory proteins, in ALS. Methods This study investigates the potential causal link between these proteins and ALS. We employed a two-sample Mendelian Randomization(MR) approach, analyzing data from large-scale genome-wide association studies to explore the relationship between 91 circulating inflammatory proteins and ALS. This included various MR methods like MR Egger, weighted median, and inverse-variance weighted, complemented by sensitivity analyses for robust results. Results Significant associations were observed between levels of inflammatory proteins, including Adenosine Deaminase, Interleukin-17C, Oncostatin-M, Leukemia Inhibitory Factor Receptor, and Osteoprotegerin, and ALS risk. Consistencies were noted across different P-value thresholds. Bidirectional MR suggested that ALS risk might influence levels of certain inflammatory proteins. Discussion Our findings, via MR analysis, indicate a potential causal relationship between circulating inflammatory proteins and ALS. This sheds new light on ALS pathophysiology and suggests possible therapeutic targets. Further research is required to confirm these results and understand the specific roles of these proteins in ALS.
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Affiliation(s)
- Chenxu Xiao
- The Affiliated Jiangsu Shengze Hospital of Nanjing Medical University, Suzhou, China
| | - Xiaochu Gu
- Medical Laboratory, Suzhou Psychiatric Hospital, The Affiliated Guangji Hospital of Soochow University, Suzhou, China
| | - Yu Feng
- The University of New South Wales, Kensington, NSW, Australia
- The University of Melbourne, Parkville, VIC, Australia
| | - Jing Shen
- The Affiliated Jiangsu Shengze Hospital of Nanjing Medical University, Suzhou, China
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Khalil B, Linsenmeier M, Smith CL, Shorter J, Rossoll W. Nuclear-import receptors as gatekeepers of pathological phase transitions in ALS/FTD. Mol Neurodegener 2024; 19:8. [PMID: 38254150 PMCID: PMC10804745 DOI: 10.1186/s13024-023-00698-1] [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: 06/05/2023] [Accepted: 12/13/2023] [Indexed: 01/24/2024] Open
Abstract
Amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD) are fatal neurodegenerative disorders on a disease spectrum that are characterized by the cytoplasmic mislocalization and aberrant phase transitions of prion-like RNA-binding proteins (RBPs). The common accumulation of TAR DNA-binding protein-43 (TDP-43), fused in sarcoma (FUS), and other nuclear RBPs in detergent-insoluble aggregates in the cytoplasm of degenerating neurons in ALS/FTD is connected to nuclear pore dysfunction and other defects in the nucleocytoplasmic transport machinery. Recent advances suggest that beyond their canonical role in the nuclear import of protein cargoes, nuclear-import receptors (NIRs) can prevent and reverse aberrant phase transitions of TDP-43, FUS, and related prion-like RBPs and restore their nuclear localization and function. Here, we showcase the NIR family and how they recognize cargo, drive nuclear import, and chaperone prion-like RBPs linked to ALS/FTD. We also discuss the promise of enhancing NIR levels and developing potentiated NIR variants as therapeutic strategies for ALS/FTD and related neurodegenerative proteinopathies.
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Affiliation(s)
- Bilal Khalil
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL, 32224, U.S.A
| | - Miriam Linsenmeier
- Department of Biochemistry and Biophysics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, 19104, U.S.A
| | - Courtney L Smith
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL, 32224, U.S.A
- Mayo Clinic Graduate School of Biomedical Sciences, Neuroscience Track, Mayo Clinic, Jacksonville, FL, 32224, U.S.A
| | - James Shorter
- Department of Biochemistry and Biophysics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, 19104, U.S.A..
| | - Wilfried Rossoll
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL, 32224, U.S.A..
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5
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Lin CY, Wu HE, Weng EFJ, Wu HC, Su TP, Wang SM. Fluvoxamine Exerts Sigma-1R to Rescue Autophagy via Pom121-Mediated Nucleocytoplasmic Transport of TFEB. Mol Neurobiol 2024:10.1007/s12035-023-03885-9. [PMID: 38180612 DOI: 10.1007/s12035-023-03885-9] [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: 09/17/2023] [Accepted: 12/12/2023] [Indexed: 01/06/2024]
Abstract
Expansion of the GGGGCC-RNA repeat is a known cause of amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD), which currently have no cure. Recent studies have indicated the activation of Sigma-1 receptor plays an important role in providing neuroprotection, especially in ALS and Alzheimer's disease. Nevertheless, the mechanisms underlying Sigma-1R activation and its effect on (G4C2)n-RNA-induced cell death remain unclear. In this study, we demonstrated that fluvoxamine is a Sigma-1R agonist that can increase chaperone activity and stabilize the protein expression of Pom121 in (G4C2)31-RNA-expressing NSC34 cells, leading to increased colocalization at the nuclear envelope. Interestingly, fluvoxamine treatment increased Pom121 protein expression without affecting transcription. In C9orf72-ALS, the nuclear translocation of TFEB autophagy factor decreased owing to nucleocytoplasmic transport defects. Our results showed that pretreatment of NSC34 cells with fluvoxamine promoted the shuttling of TFEB into the nucleus and elevated the expression of LC3-II compared to the overexpression of (G4C2)31-RNA alone. Additionally, even when used alone, fluvoxamine increases Pom121 expression and TFEB translocation. To summarize, fluvoxamine may act as a promising repurposed medicine for patients with C9orf72-ALS, as it stabilizes the nucleoporin Pom121 and promotes the translocation of TFEB in (G4C2)31-RNA-expressing NSC34 cells.
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Affiliation(s)
- Chun-Yu Lin
- School of Medicine, China Medical University, Taichung, Taiwan
- Neuroscience and Brain Disease Center, China Medical University, Taichung, Taiwan
| | - Hsiang-En Wu
- Cellular Pathobiology Section, Integrative Neuroscience Research Branch, Intramural Research Program, National Institute on Drug Abuse, NIH/DHHS, Suite 3512, 333 Cassell Drive, Baltimore, MD, 21224, USA
| | - Eddie Feng-Ju Weng
- Neuroscience and Brain Disease Center, China Medical University, Taichung, Taiwan
- Graduate Institute of Biomedical Sciences, China Medical University, Taichung, 404333, Taiwan
| | - Hsuan-Cheng Wu
- Neuroscience and Brain Disease Center, China Medical University, Taichung, Taiwan
- Graduate Institute of Biomedical Sciences, China Medical University, Taichung, 404333, Taiwan
| | - Tsung-Ping Su
- Cellular Pathobiology Section, Integrative Neuroscience Research Branch, Intramural Research Program, National Institute on Drug Abuse, NIH/DHHS, Suite 3512, 333 Cassell Drive, Baltimore, MD, 21224, USA
| | - Shao-Ming Wang
- Neuroscience and Brain Disease Center, China Medical University, Taichung, Taiwan.
- Graduate Institute of Biomedical Sciences, China Medical University, Taichung, 404333, Taiwan.
- Department of Neurology, China Medical University Hospital, Taichung, Taiwan.
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6
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Baskerville V, Rapuri S, Mehlhop E, Coyne AN. SUN1 facilitates CHMP7 nuclear influx and injury cascades in sporadic amyotrophic lateral sclerosis. Brain 2024; 147:109-121. [PMID: 37639327 PMCID: PMC10766250 DOI: 10.1093/brain/awad291] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2023] [Revised: 07/16/2023] [Accepted: 08/07/2023] [Indexed: 08/31/2023] Open
Abstract
We have recently identified the aberrant nuclear accumulation of the ESCRT-III protein CHMP7 as an initiating event that leads to a significant injury to the nuclear pore complex (NPC) characterized by the reduction of specific nucleoporins from the neuronal NPC in sporadic amyotrophic lateral sclerosis (sALS) and C9orf72 ALS/frontotemporal dementia (FTD)-induced pluripotent stem cell-derived neurons (iPSNs), a phenomenon also observed in post-mortem patient tissues. Importantly, this NPC injury is sufficient to contribute to TDP-43 dysfunction and mislocalization, a common pathological hallmark of neurodegenerative diseases. However, the molecular mechanisms and events that give rise to increased nuclear translocation and/or retention of CHMP7 to initiate this pathophysiological cascade remain largely unknown. Here, using an iPSN model of sALS, we demonstrate that impaired NPC permeability barrier integrity and interactions with the LINC complex protein SUN1 facilitate CHMP7 nuclear localization and the subsequent 'activation' of NPC injury cascades. Collectively, our data provide mechanistic insights in the pathophysiological underpinnings of ALS/FTD and highlight SUN1 as a potent contributor to and modifier of CHMP7-mediated toxicity in sALS pathogenesis.
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Affiliation(s)
- Victoria Baskerville
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
- Brain Science Institute, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Sampath Rapuri
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
- Brain Science Institute, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Emma Mehlhop
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
- Brain Science Institute, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Alyssa N Coyne
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
- Brain Science Institute, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
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7
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García Morato J, Gloeckner CJ, Kahle PJ. Proteomics elucidating physiological and pathological functions of TDP-43. Proteomics 2023; 23:e2200410. [PMID: 37671599 DOI: 10.1002/pmic.202200410] [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: 05/19/2023] [Revised: 08/02/2023] [Accepted: 08/10/2023] [Indexed: 09/07/2023]
Abstract
Trans-activation response DNA binding protein of 43 kDa (TDP-43) regulates a great variety of cellular processes in the nucleus and cytosol. In addition, a defined subset of neurodegenerative diseases is characterized by nuclear depletion of TDP-43 as well as cytosolic mislocalization and aggregation. To perform its diverse functions TDP-43 can associate with different ribonucleoprotein complexes. Combined with transcriptomics, MS interactome studies have unveiled associations between TDP-43 and the spliceosome machinery, polysomes and RNA granules. Moreover, the highly dynamic, low-valency interactions regulated by its low-complexity domain calls for innovative proximity labeling methodologies. In addition to protein partners, the analysis of post-translational modifications showed that they may play a role in the nucleocytoplasmic shuttling, RNA binding, liquid-liquid phase separation and protein aggregation of TDP-43. Here we review the various TDP-43 ribonucleoprotein complexes characterized so far, how they contribute to the diverse functions of TDP-43, and roles of post-translational modifications. Further understanding of the fluid dynamic properties of TDP-43 in ribonucleoprotein complexes, RNA granules, and self-assemblies will advance the understanding of RNA processing in cells and perhaps help to develop novel therapeutic approaches for TDPopathies.
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Affiliation(s)
- Jorge García Morato
- Laboratory of Functional Neurogenetics, Department of Neurodegeneration, German Center of Neurodegenerative Diseases and Hertie Institute for Clinical Brain Research, University of Tübingen, Tübingen, Germany
| | - Christian Johannes Gloeckner
- Research Group Functional Neuroproteomics, German Center of Neurodegenerative Diseases, Tübingen, Germany
- Core Facility for Medical Bioanalytics, Institute for Ophthalmic Research, Center for Ophthalmology, University of Tübingen, Tübingen, Germany
| | - Philipp J Kahle
- Laboratory of Functional Neurogenetics, Department of Neurodegeneration, German Center of Neurodegenerative Diseases and Hertie Institute for Clinical Brain Research, University of Tübingen, Tübingen, Germany
- Department of Biochemistry, University of Tübingen, Tübingen, Germany
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8
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Rothstein JD, Baskerville V, Rapuri S, Mehlhop E, Jafar-Nejad P, Rigo F, Bennett F, Mizielinska S, Isaacs A, Coyne AN. G 2C 4 targeting antisense oligonucleotides potently mitigate TDP-43 dysfunction in human C9orf72 ALS/FTD induced pluripotent stem cell derived neurons. Acta Neuropathol 2023; 147:1. [PMID: 38019311 PMCID: PMC10840905 DOI: 10.1007/s00401-023-02652-3] [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: 08/14/2023] [Revised: 10/09/2023] [Accepted: 10/26/2023] [Indexed: 11/30/2023]
Abstract
The G4C2 repeat expansion in the C9orf72 gene is the most common genetic cause of Amyotrophic Lateral Sclerosis and Frontotemporal Dementia. Many studies suggest that dipeptide repeat proteins produced from this repeat are toxic, yet, the contribution of repeat RNA toxicity is under investigated and even less is known regarding the pathogenicity of antisense repeat RNA. Recently, two clinical trials targeting G4C2 (sense) repeat RNA via antisense oligonucleotide failed despite a robust decrease in sense-encoded dipeptide repeat proteins demonstrating target engagement. Here, in this brief report, we show that G2C4 antisense, but not G4C2 sense, repeat RNA is sufficient to induce TDP-43 dysfunction in induced pluripotent stem cell (iPSC) derived neurons (iPSNs). Unexpectedly, only G2C4, but not G4C2 sense strand targeting, ASOs mitigate deficits in TDP-43 function in authentic C9orf72 ALS/FTD patient iPSNs. Collectively, our data suggest that the G2C4 antisense repeat RNA may be an important therapeutic target and provide insights into a possible explanation for the recent G4C2 ASO clinical trial failure.
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Affiliation(s)
- Jeffrey D Rothstein
- Brain Science Institute, Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA.
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA.
| | - Victoria Baskerville
- Brain Science Institute, Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA
| | - Sampath Rapuri
- Brain Science Institute, Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA
| | - Emma Mehlhop
- Brain Science Institute, Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA
| | | | - Frank Rigo
- Ionis Pharmaceuticals, Carlsbad, CA, 92010, USA
| | | | - Sarah Mizielinska
- UK Dementia Research Institute at King's College London, London, UK
- Department of Basic and Clinical Neuroscience, Institute of Psychiatry, Psychology and Neuroscience, Maurice Wohl Clinical Neuroscience Institute, King's College London, London, UK
| | - Adrian Isaacs
- UK Dementia Research Institute at UCL, London, UK
- Department of Neurodegenerative Disease, UCL Queen Square Institute of Neurology, London, UK
- UCL Queen Square Motor Neuron Disease Centre, UCL Queen Square Institute of Neurology, London, UK
| | - Alyssa N Coyne
- Brain Science Institute, Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA.
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA.
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9
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Cristi AC, Rapuri S, Coyne AN. Nuclear pore complex and nucleocytoplasmic transport disruption in neurodegeneration. FEBS Lett 2023; 597:2546-2566. [PMID: 37657945 PMCID: PMC10612469 DOI: 10.1002/1873-3468.14729] [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: 06/25/2023] [Revised: 07/29/2023] [Accepted: 08/24/2023] [Indexed: 09/03/2023]
Abstract
Nuclear pore complexes (NPCs) play a critical role in maintaining the equilibrium between the nucleus and cytoplasm, enabling bidirectional transport across the nuclear envelope, and are essential for proper nuclear organization and gene regulation. Perturbations in the regulatory mechanisms governing NPCs and nuclear envelope homeostasis have been implicated in the pathogenesis of several neurodegenerative diseases. The ESCRT-III pathway emerges as a critical player in the surveillance and preservation of well-assembled, functional NPCs, as well as nuclear envelope sealing. Recent studies have provided insights into the involvement of nuclear ESCRT-III in the selective reduction of specific nucleoporins associated with neurodegenerative pathologies. Thus, maintaining quality control of the nuclear envelope and NPCs represents a pivotal element in the pathological cascade leading to neurodegenerative diseases. This review describes the constituents of the nuclear-cytoplasmic transport machinery, encompassing the nuclear envelope, NPC, and ESCRT proteins, and how their structural and functional alterations contribute to the development of neurodegenerative diseases.
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Affiliation(s)
- América Chandía Cristi
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore MD 21205, USA
- Brain Science Institute, Johns Hopkins University School of Medicine, Baltimore MD 21205, USA
| | - Sampath Rapuri
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore MD 21205, USA
- Brain Science Institute, Johns Hopkins University School of Medicine, Baltimore MD 21205, USA
| | - Alyssa N Coyne
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore MD 21205, USA
- Brain Science Institute, Johns Hopkins University School of Medicine, Baltimore MD 21205, USA
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10
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Guo L, Mann JR, Mauna JC, Copley KE, Wang H, Rubien JD, Odeh HM, Lin J, Lee BL, Ganser L, Robinson E, Kim KM, Murthy AC, Paul T, Portz B, Gleixner AM, Diaz Z, Carey JL, Smirnov A, Padilla G, Lavorando E, Espy C, Shang Y, Huang EJ, Chesi A, Fawzi NL, Myong S, Donnelly CJ, Shorter J. Defining RNA oligonucleotides that reverse deleterious phase transitions of RNA-binding proteins with prion-like domains. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.09.04.555754. [PMID: 37732211 PMCID: PMC10508739 DOI: 10.1101/2023.09.04.555754] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/22/2023]
Abstract
RNA-binding proteins with prion-like domains, such as FUS and TDP-43, condense into functional liquids, which can transform into pathological fibrils that underpin fatal neurodegenerative disorders, including amyotrophic lateral sclerosis (ALS)/frontotemporal dementia (FTD). Here, we define short RNAs (24-48 nucleotides) that prevent FUS fibrillization by promoting liquid phases, and distinct short RNAs that prevent and, remarkably, reverse FUS condensation and fibrillization. These activities require interactions with multiple RNA-binding domains of FUS and are encoded by RNA sequence, length, and structure. Importantly, we define a short RNA that dissolves aberrant cytoplasmic FUS condensates, restores nuclear FUS, and mitigates FUS proteotoxicity in optogenetic models and human motor neurons. Another short RNA dissolves aberrant cytoplasmic TDP-43 condensates, restores nuclear TDP-43, and mitigates TDP-43 proteotoxicity. Since short RNAs can be effectively delivered to the human brain, these oligonucleotides could have therapeutic utility for ALS/FTD and related disorders.
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11
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Fortuna TR, Kour S, Chimata AV, Muiños-Bühl A, Anderson EN, Nelson Iv CH, Ward C, Chauhan O, O'Brien C, Rajasundaram D, Rajan DS, Wirth B, Singh A, Pandey UB. SMN regulates GEMIN5 expression and acts as a modifier of GEMIN5-mediated neurodegeneration. Acta Neuropathol 2023; 146:477-498. [PMID: 37369805 DOI: 10.1007/s00401-023-02607-8] [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: 05/17/2023] [Revised: 06/21/2023] [Accepted: 06/22/2023] [Indexed: 06/29/2023]
Abstract
GEMIN5 is essential for core assembly of small nuclear Ribonucleoproteins (snRNPs), the building blocks of spliceosome formation. Loss-of-function mutations in GEMIN5 lead to a neurodevelopmental syndrome among patients presenting with developmental delay, motor dysfunction, and cerebellar atrophy by perturbing SMN complex protein expression and assembly. Currently, molecular determinants of GEMIN5-mediated disease have yet to be explored. Here, we identified SMN as a genetic suppressor of GEMIN5-mediated neurodegeneration in vivo. We discovered that an increase in SMN expression by either SMN gene therapy replacement or the antisense oligonucleotide (ASO), Nusinersen, significantly upregulated the endogenous levels of GEMIN5 in mammalian cells and mutant GEMIN5-derived iPSC neurons. Further, we identified a strong functional association between the expression patterns of SMN and GEMIN5 in patient Spinal Muscular Atrophy (SMA)-derived motor neurons harboring loss-of-function mutations in the SMN gene. Interestingly, SMN binds to the C-terminus of GEMIN5 and requires the Tudor domain for GEMIN5 binding and expression regulation. Finally, we show that SMN upregulation ameliorates defective snRNP biogenesis and alternative splicing defects caused by loss of GEMIN5 in iPSC neurons and in vivo. Collectively, these studies indicate that SMN acts as a regulator of GEMIN5 expression and neuropathologies.
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Affiliation(s)
- Tyler R Fortuna
- Department of Pediatrics, Children's Hospital of Pittsburgh, University of Pittsburgh Medical Center, Pittsburgh, PA, USA
| | - Sukhleen Kour
- Department of Pediatrics, Children's Hospital of Pittsburgh, University of Pittsburgh Medical Center, Pittsburgh, PA, USA
| | | | - Anixa Muiños-Bühl
- Institute of Human Genetics, Center for Molecular Medicine, Center for Rare Disorders, University of Cologne, Cologne, Germany
| | - Eric N Anderson
- Department of Pediatrics, Children's Hospital of Pittsburgh, University of Pittsburgh Medical Center, Pittsburgh, PA, USA
| | - Charlie H Nelson Iv
- Department of Pediatrics, Children's Hospital of Pittsburgh, University of Pittsburgh Medical Center, Pittsburgh, PA, USA
| | - Caroline Ward
- Department of Pediatrics, Children's Hospital of Pittsburgh, University of Pittsburgh Medical Center, Pittsburgh, PA, USA
| | - Om Chauhan
- Department of Pediatrics, Children's Hospital of Pittsburgh, University of Pittsburgh Medical Center, Pittsburgh, PA, USA
| | - Casey O'Brien
- Department of Pediatrics, Division of Health Informatics, Children's Hospital of Pittsburgh, Pittsburgh, PA, USA
| | - Dhivyaa Rajasundaram
- Department of Pediatrics, Division of Health Informatics, Children's Hospital of Pittsburgh, Pittsburgh, PA, USA
| | - Deepa S Rajan
- Department of Pediatrics, Children's Hospital of Pittsburgh, University of Pittsburgh Medical Center, Pittsburgh, PA, USA
| | - Brunhilde Wirth
- Institute of Human Genetics, Center for Molecular Medicine, Center for Rare Disorders, University of Cologne, Cologne, Germany
| | - Amit Singh
- Department of Biology, University of Dayton, Dayton, OH, USA
| | - Udai Bhan Pandey
- Department of Pediatrics, Children's Hospital of Pittsburgh, University of Pittsburgh Medical Center, Pittsburgh, PA, USA.
- Children's Neuroscience Institute, Children's Hospital of Pittsburgh, Pittsburgh, PA, USA.
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12
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McGoldrick P, Robertson J. Unraveling the impact of disrupted nucleocytoplasmic transport systems in C9orf72-associated ALS. Front Cell Neurosci 2023; 17:1247297. [PMID: 37720544 PMCID: PMC10501458 DOI: 10.3389/fncel.2023.1247297] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2023] [Accepted: 08/08/2023] [Indexed: 09/19/2023] Open
Abstract
Amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD) are two adult-onset neurodegenerative diseases that are part of a common disease spectrum due to clinical, genetic, and pathological overlap. A prominent genetic factor contributing to both diseases is a hexanucleotide repeat expansion in a non-coding region of the C9orf72 gene. This mutation in C9orf72 leads to nuclear depletion and cytoplasmic aggregation of Tar DNA-RNA binding protein 43 (TDP-43). TDP-43 pathology is characteristic of the majority of ALS cases, irrespective of disease causation, and is present in ~50% of FTD cases. Defects in nucleocytoplasmic transport involving the nuclear pore complex, the Ran-GTPase cycle, and nuclear transport factors have been linked with the mislocalization of TDP-43. Here, we will explore and discuss the implications of these system abnormalities of nucleocytoplasmic transport in C9orf72-ALS/FTD, as well as in other forms of familial and sporadic ALS.
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Affiliation(s)
- Philip McGoldrick
- Tanz Centre for Research in Neurodegenerative Diseases, University of Toronto, Toronto, ON, Canada
| | - Janice Robertson
- Tanz Centre for Research in Neurodegenerative Diseases, University of Toronto, Toronto, ON, Canada
- Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, ON, Canada
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13
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De Marchi F, Franjkic T, Schito P, Russo T, Nimac J, Chami AA, Mele A, Vidatic L, Kriz J, Julien JP, Apic G, Russell RB, Rogelj B, Cannon JR, Baralle M, Agosta F, Hecimovic S, Mazzini L, Buratti E, Munitic I. Emerging Trends in the Field of Inflammation and Proteinopathy in ALS/FTD Spectrum Disorder. Biomedicines 2023; 11:1599. [PMID: 37371694 PMCID: PMC10295684 DOI: 10.3390/biomedicines11061599] [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: 04/28/2023] [Revised: 05/27/2023] [Accepted: 05/29/2023] [Indexed: 06/29/2023] Open
Abstract
Proteinopathy and neuroinflammation are two main hallmarks of neurodegenerative diseases. They also represent rare common events in an exceptionally broad landscape of genetic, environmental, neuropathologic, and clinical heterogeneity present in patients. Here, we aim to recount the emerging trends in amyotrophic lateral sclerosis (ALS) and frontotemporal degeneration (FTD) spectrum disorder. Our review will predominantly focus on neuroinflammation and systemic immune imbalance in ALS and FTD, which have recently been highlighted as novel therapeutic targets. A common mechanism of most ALS and ~50% of FTD patients is dysregulation of TAR DNA-binding protein 43 (TDP-43), an RNA/DNA-binding protein, which becomes depleted from the nucleus and forms cytoplasmic aggregates in neurons and glia. This, in turn, via both gain and loss of function events, alters a variety of TDP-43-mediated cellular events. Experimental attempts to target TDP-43 aggregates or manipulate crosstalk in the context of inflammation will be discussed. Targeting inflammation, and the immune system in general, is of particular interest because of the high plasticity of immune cells compared to neurons.
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Affiliation(s)
- Fabiola De Marchi
- Department of Neurology and ALS Centre, University of Piemonte Orientale, Maggiore Della Carità Hospital, Corso Mazzini 18, 28100 Novara, Italy; (F.D.M.); (A.M.)
| | - Toni Franjkic
- Laboratory for Molecular Immunology, Department of Biotechnology, University of Rijeka, R. Matejcic 2, 51000 Rijeka, Croatia;
- Metisox, Cambridge CB24 9NL, UK;
| | - Paride Schito
- Department of Neurology & Neuropathology Unit, Institute of Experimental Neurology (INSPE), Division of Neuroscience, IRCCS San Raffaele Scientific Institute, 20132 Milan, Italy; (P.S.); (T.R.)
| | - Tommaso Russo
- Department of Neurology & Neuropathology Unit, Institute of Experimental Neurology (INSPE), Division of Neuroscience, IRCCS San Raffaele Scientific Institute, 20132 Milan, Italy; (P.S.); (T.R.)
| | - Jerneja Nimac
- Department of Biotechnology, Jozef Stefan Institute, SI-1000 Ljubljana, Slovenia; (J.N.); (B.R.)
- Graduate School of Biomedicine, Faculty of Medicine, University of Ljubljana, SI-1000 Ljubljana, Slovenia
| | - Anna A. Chami
- CERVO Research Centre, Laval University, Quebec City, QC G1J 2G3, Canada; (A.A.C.); (J.K.); (J.-P.J.)
| | - Angelica Mele
- Department of Neurology and ALS Centre, University of Piemonte Orientale, Maggiore Della Carità Hospital, Corso Mazzini 18, 28100 Novara, Italy; (F.D.M.); (A.M.)
| | - Lea Vidatic
- Laboratory for Neurodegenerative Disease Research, Division of Molecular Medicine, Ruder Boskovic Institute, 10000 Zagreb, Croatia; (L.V.); (S.H.)
| | - Jasna Kriz
- CERVO Research Centre, Laval University, Quebec City, QC G1J 2G3, Canada; (A.A.C.); (J.K.); (J.-P.J.)
| | - Jean-Pierre Julien
- CERVO Research Centre, Laval University, Quebec City, QC G1J 2G3, Canada; (A.A.C.); (J.K.); (J.-P.J.)
| | | | | | - Boris Rogelj
- Department of Biotechnology, Jozef Stefan Institute, SI-1000 Ljubljana, Slovenia; (J.N.); (B.R.)
- Faculty of Chemistry and Chemical Technology, University of Ljubljana, SI-1000 Ljubljana, Slovenia
| | - Jason R. Cannon
- School of Health Sciences, Purdue University, West Lafayette, IN 47907, USA;
- Purdue Institute for Integrative Neuroscience, Purdue University, West Lafayette, IN 47907, USA
| | | | - Federica Agosta
- Neuroimaging Research Unit, Institute of Experimental Neurology, Division of Neuroscience, IRCCS San Raffaele Scientific Institute, 20132 Milan, Italy;
| | - Silva Hecimovic
- Laboratory for Neurodegenerative Disease Research, Division of Molecular Medicine, Ruder Boskovic Institute, 10000 Zagreb, Croatia; (L.V.); (S.H.)
| | - Letizia Mazzini
- Department of Neurology and ALS Centre, University of Piemonte Orientale, Maggiore Della Carità Hospital, Corso Mazzini 18, 28100 Novara, Italy; (F.D.M.); (A.M.)
| | - Emanuele Buratti
- International Centre for Genetic Engineering and Biotechnology (ICGEB), Padriciano 99, 34149 Trieste, Italy
| | - Ivana Munitic
- Laboratory for Molecular Immunology, Department of Biotechnology, University of Rijeka, R. Matejcic 2, 51000 Rijeka, Croatia;
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14
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Thomas L, Taleb Ismail B, Askjaer P, Seydoux G. Nucleoporin foci are stress-sensitive condensates dispensable for C. elegans nuclear pore assembly. EMBO J 2023:e112987. [PMID: 37254647 DOI: 10.15252/embj.2022112987] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2022] [Revised: 05/02/2023] [Accepted: 05/10/2023] [Indexed: 06/01/2023] Open
Abstract
Nucleoporins (Nups) assemble nuclear pores that form the permeability barrier between nucleoplasm and cytoplasm. Nucleoporins also localize in cytoplasmic foci proposed to function as pore pre-assembly intermediates. Here, we characterize the composition and incidence of cytoplasmic Nup foci in an intact animal, C. elegans. We find that, in young non-stressed animals, Nup foci only appear in developing sperm, oocytes and embryos, tissues that express high levels of nucleoporins. The foci are condensates of highly cohesive FG repeat-containing nucleoporins (FG-Nups), which are maintained near their solubility limit in the cytoplasm by posttranslational modifications and chaperone activity. Only a minor fraction of FG-Nup molecules concentrate in Nup foci, which dissolve during M phase and are dispensable for nuclear pore assembly. Nucleoporin condensation is enhanced by stress and advancing age, and overexpression of a single FG-Nup in post-mitotic neurons is sufficient to induce ectopic condensation and organismal paralysis. We speculate that Nup foci are non-essential and potentially toxic condensates whose assembly is actively suppressed in healthy cells.
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Affiliation(s)
- Laura Thomas
- HHMI and Department of Molecular Biology and Genetics, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Basma Taleb Ismail
- HHMI and Department of Molecular Biology and Genetics, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Peter Askjaer
- Andalusian Center for Developmental Biology (CABD), CSIC/JA/Universidad Pablo de Olavide, Seville, Spain
| | - Geraldine Seydoux
- HHMI and Department of Molecular Biology and Genetics, Johns Hopkins University School of Medicine, Baltimore, MD, USA
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15
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Van't Spijker HM, Almeida S. How villains are made: The translation of dipeptide repeat proteins in C9ORF72-ALS/FTD. Gene 2023; 858:147167. [PMID: 36621656 PMCID: PMC9928902 DOI: 10.1016/j.gene.2023.147167] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2022] [Accepted: 01/03/2023] [Indexed: 01/07/2023]
Abstract
A hexanucleotide repeat expansion in the C9ORF72 gene is the most common genetic alteration associated with amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD). These neurodegenerative diseases share genetic, clinical and pathological features. The mutation in C9ORF72 appears to drive pathogenesis through a combination of loss of C9ORF72 normal function and gain of toxic effects due to the repeat expansion, which result in aggregation prone expanded RNAs and dipeptide repeat (DPR) proteins. Studies in cellular and animal models indicate that the DPR proteins are the more toxic species. Thus, a large body of research has focused on identifying the cellular pathways most directly impacted by these toxic proteins, with the goal of characterizing disease pathogenesis and nominating potential targets for therapeutic development. The preventative block of the production of the toxic proteins before they can cause harm is a second strategy of intense focus. Despite the considerable amount of effort dedicated to this prophylactic approach, it is still unclear how the DPR proteins are synthesized from RNAs harboring repeat expansions. In this review, we summarize our current knowledge of the specific protein translation mechanisms shown to account for the synthesis of DPR proteins. We will then discuss how enhanced understanding of the composition of these toxic effectors could help in refining disease mechanisms, and paving the way to identify and design effective prophylactic therapies for C9ORF72 ALS-FTD.
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Affiliation(s)
- Heleen M Van't Spijker
- Program in Molecular Medicine, University of Massachusetts Chan Medical School, Worcester, MA 01605, USA
| | - Sandra Almeida
- Department of Neurology, University of Massachusetts Chan Medical School, Worcester, MA 01605, USA.
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16
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Mueller S, Decker L, Menge S, Ludolph AC, Freischmidt A. The Fragile X Protein Family in Amyotrophic Lateral Sclerosis. Mol Neurobiol 2023; 60:3898-3910. [PMID: 36991279 DOI: 10.1007/s12035-023-03330-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2022] [Accepted: 03/23/2023] [Indexed: 03/31/2023]
Abstract
The fragile X protein (FXP) family comprises the multifunctional RNA-binding proteins FMR1, FXR1, and FXR2 that play an important role in RNA metabolism and regulation of translation, but also in DNA damage and cellular stress responses, mitochondrial organization, and more. FMR1 is well known for its implication in neurodevelopmental diseases. Recent evidence suggests substantial contribution of this protein family to amyotrophic lateral sclerosis (ALS) pathogenesis. ALS is a highly heterogeneous neurodegenerative disease with multiple genetic and unclear environmental causes and very limited treatment options. The loss of motoneurons in ALS is still poorly understood, especially because pathogenic mechanisms are often restricted to patients with mutations in specific causative genes. Identification of converging disease mechanisms evident in most patients and suitable for therapeutic intervention is therefore of high importance. Recently, deregulation of the FXPs has been linked to pathogenic processes in different types of ALS. Strikingly, in many cases, available data points towards loss of expression and/or function of the FXPs early in the disease, or even at the presymptomatic state. In this review, we briefly introduce the FXPs and summarize available data about these proteins in ALS. This includes their relation to TDP-43, FUS, and ALS-related miRNAs, as well as their possible contribution to pathogenic protein aggregation and defective RNA editing. Furthermore, open questions that need to be addressed before definitively judging suitability of these proteins as novel therapeutic targets are discussed.
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Affiliation(s)
- Sarah Mueller
- Department of Neurology, Ulm University, Albert-Einstein-Allee 11, 89081, Ulm, Germany
| | - Lorena Decker
- Department of Neurology, Ulm University, Albert-Einstein-Allee 11, 89081, Ulm, Germany
| | - Sonja Menge
- Department of Neurology, Ulm University, Albert-Einstein-Allee 11, 89081, Ulm, Germany
| | - Albert C Ludolph
- Department of Neurology, Ulm University, Albert-Einstein-Allee 11, 89081, Ulm, Germany
- German Center For Neurodegenerative Diseases (DZNE) Ulm, Ulm, Germany
| | - Axel Freischmidt
- Department of Neurology, Ulm University, Albert-Einstein-Allee 11, 89081, Ulm, Germany.
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17
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Kumar MS, Stallworth KM, Murthy AC, Lim SM, Li N, Jain A, Munro JB, Fawzi NL, Lagier-Tourenne C, Bosco DA. Interactions between FUS and the C-terminal Domain of Nup62 are Sufficient for their Co-phase Separation into Amorphous Assemblies. J Mol Biol 2023; 435:167972. [PMID: 36690069 PMCID: PMC10329203 DOI: 10.1016/j.jmb.2023.167972] [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: 09/08/2022] [Revised: 12/29/2022] [Accepted: 01/15/2023] [Indexed: 01/22/2023]
Abstract
Deficient nucleocytoplasmic transport is emerging as a pathogenic feature of amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD), including in ALS caused by mutations in Fused in Sarcoma (FUS). Recently, both wild-type and ALS-linked mutant FUS were shown to directly interact with the phenylalanine-glycine (FG)-rich nucleoporin 62 (Nup62) protein, where FUS WT/ Nup62 interactions were enriched within the nucleus but ALS-linked mutant FUS/ Nup62 interactions were enriched within the cytoplasm of cells. Nup62 is a central channel Nup that has a prominent role in forming the selectivity filter within the nuclear pore complex and in regulating effective nucleocytoplasmic transport. Under conditions where FUS phase separates into liquid droplets in vitro, the addition of Nup62 caused the synergistic formation of amorphous assemblies containing both FUS and Nup62. Here, we examined the molecular determinants of this process using recombinant FUS and Nup62 proteins and biochemical approaches. We demonstrate that the structured C-terminal domain of Nup62 containing an alpha-helical coiled-coil region plays a dominant role in binding FUS and is sufficient for inducing the formation of FUS/Nup62 amorphous assemblies. In contrast, the natively unstructured, F/G repeat-rich N-terminal domain of Nup62 modestly contributed to FUS/Nup62 phase separation behavior. Expression of individual Nup62 domain constructs in human cells confirmed that the Nup62 C-terminal domain is essential for localization of the protein to the nuclear envelope. Our results raise the possibility that interactions between FUS and the C-terminal domain of Nup62 can influence the function of Nup62 under physiological and/or pathological conditions.
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Affiliation(s)
- Meenakshi Sundaram Kumar
- Department of Neurology, University of Massachusetts Chan Medical School, Worcester, Massachusetts, MA 01605, USA; Biochemistry and Molecular Biotechnology Program, Morningside Graduate School of Biomedical Sciences, University of Massachusetts Chan Medical School, Worcester, MA 01605, USA
| | - Karly M Stallworth
- Department of Neurology, University of Massachusetts Chan Medical School, Worcester, Massachusetts, MA 01605, USA
| | - Anastasia C Murthy
- Department of Molecular Biology, Cell Biology, and Biochemistry, Brown University, Providence, RI, USA
| | - Su Min Lim
- Department of Neurology, The Sean M. Healey and AMG Center for ALS at Mass General, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114, USA; Broad Institute of Harvard and MIT, Cambridge, MA 02142, USA
| | - Nan Li
- Department of Neurology, The Sean M. Healey and AMG Center for ALS at Mass General, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114, USA; Broad Institute of Harvard and MIT, Cambridge, MA 02142, USA
| | - Aastha Jain
- Department of Microbiology and Physiological Systems, University of Massachusetts Chan Medical School, Worcester, MA 01605, USA
| | - James B Munro
- Department of Microbiology and Physiological Systems, University of Massachusetts Chan Medical School, Worcester, MA 01605, USA; Department of Biochemistry and Molecular Biotechnology, University of Massachusetts Chan Medical School, Worcester, MA 01605, USA
| | - Nicolas L Fawzi
- Department of Molecular Biology, Cell Biology, and Biochemistry, Brown University, Providence, RI, USA
| | - Clotilde Lagier-Tourenne
- Department of Neurology, The Sean M. Healey and AMG Center for ALS at Mass General, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114, USA; Broad Institute of Harvard and MIT, Cambridge, MA 02142, USA
| | - Daryl A Bosco
- Department of Neurology, University of Massachusetts Chan Medical School, Worcester, Massachusetts, MA 01605, USA.
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18
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Zhao J, Wang W, Yan K, Zhao H, Zhang Z, Wang Y, Zhu W, Chen S. RNA-seq reveals Nup62 as a potential regulator for cell division after traumatic brain injury in mice hippocampus. PeerJ 2023; 11:e14913. [PMID: 36908815 PMCID: PMC10000302 DOI: 10.7717/peerj.14913] [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: 10/10/2022] [Accepted: 01/25/2023] [Indexed: 03/09/2023] Open
Abstract
Background Hippocampus impairment is a common condition encountered in the clinical diagnosis and treatment of traumatic brain injury (TBI). Several studies have investigated this phenomenon. However, its molecular mechanism remains unclear. Methods In this study, Illumina RNA-seq technology was used to determine the gene expression profile in mice hippocampus after TBI. We then conducted bioinformatics analysis to identify the altered gene expression signatures and mechanisms related to TBI-induced pathology in the hippocampus. Real-time quantitative polymerase chain reaction and western blot were adopted to verify the sequencing results. Results The controlled cortical impact was adopted as the TBI model. Hippocampal specimens were removed for sequencing. Bioinformatics analysis identified 27 upregulated and 17 downregulated differentially expressed genes (DEGs) in post-TBI mouse models. Potential biological functions of the genes were determined via Gene Set Enrichment Analysis (GSEA)-based Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses, which suggested a series of functional changes in the nervous system. Specifically, the nucleoporin 62 (Nup62) DEG was discussed and verified. Gene ontology biological process enriched analysis suggests that the cell division was upregulated significantly. The present study may be helpful for the treatment of impaired hippocampus after TBI in the future.
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Affiliation(s)
- Jianwei Zhao
- Department of Neurosurgery, Suzhou Science & Technology Town Hospital, Suzhou, Jiangsu Province, China
- Department of Neurosurgery, Shanghai Sixth People’s Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai, Shanghai, China
| | - Weihua Wang
- Department of Neurosurgery, Suzhou Science & Technology Town Hospital, Suzhou, Jiangsu Province, China
| | - Ke Yan
- Department of Neurosurgery, Suzhou Science & Technology Town Hospital, Suzhou, Jiangsu Province, China
| | - Haifeng Zhao
- Department of Pathology, Suzhou Science & Technology Town Hospital, Suzhou, Jiangsu Province, China
| | - Zhen Zhang
- Department of Neurosurgery, Suzhou Science & Technology Town Hospital, Suzhou, Jiangsu Province, China
| | - Yu Wang
- Department of Neurosurgery, Suzhou Science & Technology Town Hospital, Suzhou, Jiangsu Province, China
| | - Wenyu Zhu
- Department of Neurosurgery, Suzhou Science & Technology Town Hospital, Suzhou, Jiangsu Province, China
| | - Shiwen Chen
- Department of Neurosurgery, Shanghai Sixth People’s Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai, Shanghai, China
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19
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Khalil B, Chhangani D, Wren MC, Smith CL, Lee JH, Li X, Puttinger C, Tsai CW, Fortin G, Morderer D, Gao J, Liu F, Lim CK, Chen J, Chou CC, Croft CL, Gleixner AM, Donnelly CJ, Golde TE, Petrucelli L, Oskarsson B, Dickson DW, Zhang K, Shorter J, Yoshimura SH, Barmada SJ, Rincon-Limas DE, Rossoll W. Nuclear import receptors are recruited by FG-nucleoporins to rescue hallmarks of TDP-43 proteinopathy. Mol Neurodegener 2022; 17:80. [PMID: 36482422 PMCID: PMC9733332 DOI: 10.1186/s13024-022-00585-1] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2022] [Accepted: 11/23/2022] [Indexed: 12/13/2022] Open
Abstract
BACKGROUND Cytoplasmic mislocalization and aggregation of TAR DNA-binding protein-43 (TDP-43) is a hallmark of the amyotrophic lateral sclerosis and frontotemporal dementia (ALS/FTD) disease spectrum, causing both nuclear loss-of-function and cytoplasmic toxic gain-of-function phenotypes. While TDP-43 proteinopathy has been associated with defects in nucleocytoplasmic transport, this process is still poorly understood. Here we study the role of karyopherin-β1 (KPNB1) and other nuclear import receptors in regulating TDP-43 pathology. METHODS We used immunostaining, immunoprecipitation, biochemical and toxicity assays in cell lines, primary neuron and organotypic mouse brain slice cultures, to determine the impact of KPNB1 on the solubility, localization, and toxicity of pathological TDP-43 constructs. Postmortem patient brain and spinal cord tissue was stained to assess KPNB1 colocalization with TDP-43 inclusions. Turbidity assays were employed to study the dissolution and prevention of aggregation of recombinant TDP-43 fibrils in vitro. Fly models of TDP-43 proteinopathy were used to determine the effect of KPNB1 on their neurodegenerative phenotype in vivo. RESULTS We discovered that several members of the nuclear import receptor protein family can reduce the formation of pathological TDP-43 aggregates. Using KPNB1 as a model, we found that its activity depends on the prion-like C-terminal region of TDP-43, which mediates the co-aggregation with phenylalanine and glycine-rich nucleoporins (FG-Nups) such as Nup62. KPNB1 is recruited into these co-aggregates where it acts as a molecular chaperone that reverses aberrant phase transition of Nup62 and TDP-43. These findings are supported by the discovery that Nup62 and KPNB1 are also sequestered into pathological TDP-43 aggregates in ALS/FTD postmortem CNS tissue, and by the identification of the fly ortholog of KPNB1 as a strong protective modifier in Drosophila models of TDP-43 proteinopathy. Our results show that KPNB1 can rescue all hallmarks of TDP-43 pathology, by restoring its solubility and nuclear localization, and reducing neurodegeneration in cellular and animal models of ALS/FTD. CONCLUSION Our findings suggest a novel NLS-independent mechanism where, analogous to its canonical role in dissolving the diffusion barrier formed by FG-Nups in the nuclear pore, KPNB1 is recruited into TDP-43/FG-Nup co-aggregates present in TDP-43 proteinopathies and therapeutically reverses their deleterious phase transition and mislocalization, mitigating neurodegeneration.
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Affiliation(s)
- Bilal Khalil
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL, 32224, USA
| | - Deepak Chhangani
- Department of Neurology, McKnight Brain Institute, Norman Fixel Institute for Neurological Diseases, University of Florida, Gainesville, FL, 32610, USA
| | - Melissa C Wren
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL, 32224, USA
| | - Courtney L Smith
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL, 32224, USA
- Mayo Clinic Graduate School of Biomedical Sciences, Neuroscience Track, Mayo Clinic, Jacksonville, FL, USA
| | - Jannifer H Lee
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL, 32224, USA
- Mayo Clinic Graduate School of Biomedical Sciences, Neuroscience Track, Mayo Clinic, Jacksonville, FL, USA
| | - Xingli Li
- Department of Neurology, University of Michigan, Ann Arbor, MI, 48109, USA
| | | | - Chih-Wei Tsai
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL, 32224, USA
| | - Gael Fortin
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL, 32224, USA
| | - Dmytro Morderer
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL, 32224, USA
| | - Junli Gao
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL, 32224, USA
| | - Feilin Liu
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL, 32224, USA
| | - Chun Kim Lim
- Graduate School of Biostudies, Kyoto University, Yoshida-konoe, Sakyo-ku, Kyoto, Japan
| | - Jingjiao Chen
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL, 32224, USA
- Geriatric Department, Affiliated Hospital of Qingdao University, Qingdao, Shandong, China
| | - Ching-Chieh Chou
- Department of Biology, Stanford University, Stanford, CA, 94305, USA
| | - Cara L Croft
- Department of Neuroscience, Center for Translational Research in Neurodegenerative Disease, University of Florida, Gainesville, FL, 32610, USA
- UK Dementia Research Institute at University College London, London, UK
| | - Amanda M Gleixner
- Department of Neurobiology, University of Pittsburgh School of Medicine, Pittsburgh, PA, 15213, USA
- LiveLikeLou Center for ALS Research, University of Pittsburgh Brain Institute, Pittsburgh, PA, 15261, USA
| | - Christopher J Donnelly
- Department of Neurobiology, University of Pittsburgh School of Medicine, Pittsburgh, PA, 15213, USA
- LiveLikeLou Center for ALS Research, University of Pittsburgh Brain Institute, Pittsburgh, PA, 15261, USA
| | - Todd E Golde
- Department of Neurology, McKnight Brain Institute, Norman Fixel Institute for Neurological Diseases, University of Florida, Gainesville, FL, 32610, USA
- Department of Neuroscience, Center for Translational Research in Neurodegenerative Disease, University of Florida, Gainesville, FL, 32610, USA
| | | | | | - Dennis W Dickson
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL, 32224, USA
| | - Ke Zhang
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL, 32224, USA
| | - James Shorter
- Department of Biochemistry and Biophysics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - Shige H Yoshimura
- Graduate School of Biostudies, Kyoto University, Yoshida-konoe, Sakyo-ku, Kyoto, Japan
| | - Sami J Barmada
- Department of Neurology, University of Michigan, Ann Arbor, MI, 48109, USA
| | - Diego E Rincon-Limas
- Department of Neurology, McKnight Brain Institute, Norman Fixel Institute for Neurological Diseases, University of Florida, Gainesville, FL, 32610, USA
- Department of Neuroscience, Center for Translational Research in Neurodegenerative Disease, University of Florida, Gainesville, FL, 32610, USA
- Genetics Institute, University of Florida, Gainesville, FL, 32610, USA
| | - Wilfried Rossoll
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL, 32224, USA.
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20
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Rhine K, Al-Azzam N, Yu T, Yeo GW. Aging RNA granule dynamics in neurodegeneration. Front Mol Biosci 2022; 9:991641. [PMID: 36188213 PMCID: PMC9523239 DOI: 10.3389/fmolb.2022.991641] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2022] [Accepted: 08/22/2022] [Indexed: 12/30/2022] Open
Abstract
Disordered RNA-binding proteins and repetitive RNA sequences are the main genetic causes of several neurodegenerative diseases, including amyotrophic lateral sclerosis and Huntington’s disease. Importantly, these components also seed the formation of cytoplasmic liquid-like granules, like stress granules and P bodies. Emerging evidence demonstrates that healthy granules formed via liquid-liquid phase separation can mature into solid- or gel-like inclusions that persist within the cell. These solidified inclusions are a precursor to the aggregates identified in patients, demonstrating that dysregulation of RNA granule biology is an important component of neurodegeneration. Here, we review recent literature highlighting how RNA molecules seed proteinaceous granules, the mechanisms of healthy turnover of RNA granules in cells, which biophysical properties underly a transition to solid- or gel-like material states, and why persistent granules disrupt the cellular homeostasis of neurons. We also identify various methods that will illuminate the contributions of disordered proteins and RNAs to neurodegeneration in ongoing research efforts.
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Affiliation(s)
- Kevin Rhine
- Department of Cellular and Molecular Medicine, University of California, San Diego, San Diego, CA, United States
- Stem Cell Program, University of California, San Diego, San Diego, CA, United States
- Institute for Genomic Medicine, University of California, San Diego, San Diego, CA, United States
| | - Norah Al-Azzam
- Department of Cellular and Molecular Medicine, University of California, San Diego, San Diego, CA, United States
- Stem Cell Program, University of California, San Diego, San Diego, CA, United States
- Institute for Genomic Medicine, University of California, San Diego, San Diego, CA, United States
- Neurosciences Graduate Program, University of California, San Diego, San Diego, CA, United States
| | - Tao Yu
- Department of Cellular and Molecular Medicine, University of California, San Diego, San Diego, CA, United States
- Stem Cell Program, University of California, San Diego, San Diego, CA, United States
- Institute for Genomic Medicine, University of California, San Diego, San Diego, CA, United States
| | - Gene W. Yeo
- Department of Cellular and Molecular Medicine, University of California, San Diego, San Diego, CA, United States
- Stem Cell Program, University of California, San Diego, San Diego, CA, United States
- Institute for Genomic Medicine, University of California, San Diego, San Diego, CA, United States
- Neurosciences Graduate Program, University of California, San Diego, San Diego, CA, United States
- *Correspondence: Gene W. Yeo,
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Nag N, Tripathi T. Mislocalization of Nup62 Contributes to TDP-43 Proteinopathy in ALS/FTLD. ACS Chem Neurosci 2022; 13:2544-2546. [PMID: 36001801 DOI: 10.1021/acschemneuro.2c00480] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
The nucleocytoplasmic transport (NCT) is impaired in C9-ALS/FTLD, a common genetically caused form of ALS and FTLD. The NCT is regulated by proteins called FG-nucleoporins (FG-Nups), with domains enriched in phenylalanine-glycine repeats. However, the relationship between FG-Nups and TDP-43, an RBP found to be mislocalized in ALS/FTLD patients, has not been defined. A recent study found that a critical protein, FG-Nup62, is mislocalized both in vivo and in vitro in diseased states. The mislocalized Nup62 was colocalized with TDP-43 in cytoplasmic inclusions and promoted its liquid-to-solid transition. The work highlights the involvement of Nup62 in the pathogenesis of ALS/FTLD and the interaction between Nup62 and TDP-43.
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Affiliation(s)
- Niharika Nag
- Molecular and Structural Biophysics Laboratory, Department of Biochemistry, North-Eastern Hill University, Shillong 793022, India
| | - Timir Tripathi
- Molecular and Structural Biophysics Laboratory, Department of Biochemistry, North-Eastern Hill University, Shillong 793022, India.,Regional Director's Office, Indira Gandhi National Open University (IGNOU), Regional Centre Kohima, Kenuozou, Kohima 797001, India
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