1
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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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Sirtori R, Gregoire M, Collins A, Santangelo S, Chatragadda B, Cullen R, Ratti A, Fallini C. Altered nuclear envelope homeostasis is a key pathogenic event in C9ORF72-linked ALS/FTD. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.02.01.578318. [PMID: 38352403 PMCID: PMC10862841 DOI: 10.1101/2024.02.01.578318] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/16/2024]
Abstract
ALS and FTD are complex neurodegenerative disorders that primarily affects motor neurons in the brain and spinal cord, and cortical neurons in the frontal lobe. Although the pathogenesis of ALS/FTD is unclear, recent research spotlights nucleocytoplasmic transport impairment, DNA damage, and nuclear abnormalities as drivers of neuronal death. In this study, we show that loss of nuclear envelope (NE) integrity is a key pathology associated with nuclear pore complex (NPC) injury in C9ORF72 mutant neurons. Importantly, we show that mechanical stresses generated by cytoskeletal forces on the NE can lead to NPC injury, loss of nuclear integrity, and accumulation of DNA damage. Importantly, we demonstrate that restoring NE tensional homeostasis, by disconnecting the nucleus from the cytoskeleton, can rescue NPC injury and reduce DNA damage in C9ORF72 mutant cells. Together, our data suggest that modulation of NE homeostasis and repair may represent a novel and promising therapeutic target for ALS/FTD.
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3
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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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4
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Liu ML, Ma S, Tai W, Zhong X, Ni H, Zou Y, Wang J, Zhang CL. Screens in aging-relevant human ALS-motor neurons identify MAP4Ks as therapeutic targets for the disease. Cell Death Dis 2024; 15:4. [PMID: 38177100 PMCID: PMC10766628 DOI: 10.1038/s41419-023-06395-7] [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: 09/01/2023] [Revised: 12/13/2023] [Accepted: 12/15/2023] [Indexed: 01/06/2024]
Abstract
Effective therapeutics is much needed for amyotrophic lateral sclerosis (ALS), an adult-onset neurodegenerative disease mainly affecting motor neurons. By screening chemical compounds in human patient-derived and aging-relevant motor neurons, we identify a neuroprotective compound and show that MAP4Ks may serve as therapeutic targets for treating ALS. The lead compound broadly improves survival and function of motor neurons directly converted from human ALS patients. Mechanistically, it works as an inhibitor of MAP4Ks, regulates the MAP4Ks-HDAC6-TUBA4A-RANGAP1 pathway, and normalizes subcellular distribution of RANGAP1 and TDP-43. Finally, in an ALS mouse model we show that inhibiting MAP4Ks preserves motor neurons and significantly extends animal lifespan.
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Affiliation(s)
- Meng-Lu Liu
- Department of Molecular Biology, Hamon Center for Regenerative Science and Medicine, University of Texas Southwestern Medical Center, Dallas, TX, 75390, USA
| | - Shuaipeng Ma
- Department of Molecular Biology, Hamon Center for Regenerative Science and Medicine, University of Texas Southwestern Medical Center, Dallas, TX, 75390, USA
| | - Wenjiao Tai
- Department of Molecular Biology, Hamon Center for Regenerative Science and Medicine, University of Texas Southwestern Medical Center, Dallas, TX, 75390, USA
| | - Xiaoling Zhong
- Department of Molecular Biology, Hamon Center for Regenerative Science and Medicine, University of Texas Southwestern Medical Center, Dallas, TX, 75390, USA
| | - Haoqi Ni
- Department of Molecular Biology, Hamon Center for Regenerative Science and Medicine, University of Texas Southwestern Medical Center, Dallas, TX, 75390, USA
| | - Yuhua Zou
- Department of Molecular Biology, Hamon Center for Regenerative Science and Medicine, University of Texas Southwestern Medical Center, Dallas, TX, 75390, USA
| | - Jingcheng Wang
- Department of Molecular Biology, Hamon Center for Regenerative Science and Medicine, University of Texas Southwestern Medical Center, Dallas, TX, 75390, USA
| | - Chun-Li Zhang
- Department of Molecular Biology, Hamon Center for Regenerative Science and Medicine, University of Texas Southwestern Medical Center, Dallas, TX, 75390, USA.
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5
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Brosens N, Lesuis SL, Rao-Ruiz P, van den Oever MC, Krugers HJ. Shaping Memories Via Stress: A Synaptic Engram Perspective. Biol Psychiatry 2023:S0006-3223(23)01720-1. [PMID: 37977215 DOI: 10.1016/j.biopsych.2023.11.008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/17/2023] [Revised: 10/09/2023] [Accepted: 11/05/2023] [Indexed: 11/19/2023]
Abstract
Stress modulates the activity of various memory systems and can thereby guide behavioral interaction with the environment in an adaptive or maladaptive manner. At the cellular level, a large body of evidence indicates that (nor)adrenaline and glucocorticoid release induced by acute stress exposure affects synapse function and synaptic plasticity, which are critical substrates for learning and memory. Recent evidence suggests that memories are supported in the brain by sparsely distributed neurons within networks, termed engram cell ensembles. While the physiological and molecular effects of stress on the synapse are increasingly well characterized, how these synaptic modifications shape the multiscale dynamics of engram cell ensembles is still poorly understood. In this review, we discuss and integrate recent information on how acute stress affects synapse function and how this may alter engram cell ensembles and their synaptic connectivity to shape memory strength and memory precision. We provide a mechanistic framework of a synaptic engram under stress and put forward outstanding questions that address knowledge gaps in our understanding of the mechanisms that underlie stress-induced memory modulation.
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Affiliation(s)
- Niek Brosens
- Brain Plasticity Group, Swammerdam Institute for Life Sciences-Center for Neuroscience, University of Amsterdam, Amsterdam, the Netherlands.
| | - Sylvie L Lesuis
- Brain Plasticity Group, Swammerdam Institute for Life Sciences-Center for Neuroscience, University of Amsterdam, Amsterdam, the Netherlands; Cellular and Cognitive Neuroscience group, Swammerdam Institute for Life Sciences-Center for Neuroscience, University of Amsterdam, Amsterdam, the Netherlands
| | - Priyanka Rao-Ruiz
- Department of Molecular and Cellular Neurobiology, Center for Neurogenomics and Cognitive Research, Amsterdam Neuroscience, Vrije Universiteit Amsterdam, Amsterdam, the Netherlands
| | - Michel C van den Oever
- Department of Molecular and Cellular Neurobiology, Center for Neurogenomics and Cognitive Research, Amsterdam Neuroscience, Vrije Universiteit Amsterdam, Amsterdam, the Netherlands
| | - Harm J Krugers
- Brain Plasticity Group, Swammerdam Institute for Life Sciences-Center for Neuroscience, University of Amsterdam, Amsterdam, the Netherlands.
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6
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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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7
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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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8
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Liu ML, Ma S, Tai W, Zhong X, Ni H, Zou Y, Wang J, Zhang CL. Chemical screens in aging-relevant human motor neurons identify MAP4Ks as therapeutic targets for amyotrophic lateral sclerosis. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.04.24.538014. [PMID: 37162962 PMCID: PMC10168247 DOI: 10.1101/2023.04.24.538014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
Effective therapeutics is much needed for amyotrophic lateral sclerosis (ALS), an adult-onset neurodegenerative disease mainly affecting motor neurons. By screening chemical compounds in human patient-derived and aging-relevant motor neurons, we identify a neuroprotective compound and show that MAP4Ks may serve as therapeutic targets for treating ALS. The lead compound broadly improves survival and function of motor neurons directly converted from human ALS patients. Mechanistically, it works as an inhibitor of MAP4Ks, regulates the MAP4Ks-HDAC6-TUBA4A-RANGAP1 pathway, and normalizes subcellular distribution of RANGAP1 and TDP-43. Finally, in an ALS mouse model we show that inhibiting MAP4Ks preserves motor neurons and significantly extends animal lifespan.
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Affiliation(s)
- Meng-Lu Liu
- Department of Molecular Biology, Hamon Center for Regenerative Science and Medicine, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Shuaipeng Ma
- Department of Molecular Biology, Hamon Center for Regenerative Science and Medicine, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Wenjiao Tai
- Department of Molecular Biology, Hamon Center for Regenerative Science and Medicine, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Xiaoling Zhong
- Department of Molecular Biology, Hamon Center for Regenerative Science and Medicine, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Haoqi Ni
- Department of Molecular Biology, Hamon Center for Regenerative Science and Medicine, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Yuhua Zou
- Department of Molecular Biology, Hamon Center for Regenerative Science and Medicine, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Jingcheng Wang
- Department of Molecular Biology, Hamon Center for Regenerative Science and Medicine, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Chun-Li Zhang
- Department of Molecular Biology, Hamon Center for Regenerative Science and Medicine, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
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9
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Liu Y, Ding M, Pan S, Zhou R, Yao J, Fu R, Yu H, Lu Z. MicroRNA-23a-3p is upregulated in plasma exosomes of bulbar-onset ALS patients and targets ERBB4. Neuroscience 2023:S0306-4522(23)00250-6. [PMID: 37290686 DOI: 10.1016/j.neuroscience.2023.05.030] [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: 01/09/2023] [Revised: 05/24/2023] [Accepted: 05/27/2023] [Indexed: 06/10/2023]
Abstract
Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease related to the progressive death of motor neurons. Understanding the pathogenesis of ALS continues to provide considerable challenges. Bulbar-onset ALS involves faster functional loss and shorter survival time than spinal cord-onset ALS. However, debate is ongoing regarding typical plasma miRNA changes in ALS patients with bulbar onset. Exosomal miRNAs have not yet been described as a tool for bulbar-onset ALS diagnosis or prognosis prediction. In this study, candidate exosomal miRNAs were identified by small RNA sequencing using samples from patients with bulbar-onset ALS and healthy controls. Potential pathogenic mechanisms were identified through enrichment analysis of target genes for differential miRNAs. Expression of miR-16-5p, miR-23a-3p, miR-22-3p, and miR-93-5p was significantly up-regulated in plasma exosomes from bulbar-onset ALS patients compared with healthy control subjects. Among them, miR-16-5p and miR-23a-3p were significantly lower in spinal-onset ALS patients than those with bulbar-onset. Furthermore, up-regulation of miR-23a-3p in motor neuron-like NSC-34 cells promoted apoptosis and inhibited cell viability. This miRNA was found to directly target ERBB4 and regulate the AKT/GSK3β pathway. Collectively, the above miRNAs and their targets are related to the development of bulbar-onset ALS. Our research indicates that miR-23a-3p might have an effect on motor neuron loss observed in bulbar-onset ALS and may be a novel target for the therapy of ALS in the future.
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Affiliation(s)
- Yue Liu
- Department of Neurology, Renmin Hospital of Wuhan University, Wuhan, China
| | - Man Ding
- Department of Neurology, Renmin Hospital of Wuhan University, Wuhan, China
| | - Sijia Pan
- Department of Neurology, Renmin Hospital of Wuhan University, Wuhan, China
| | - Rumeng Zhou
- Department of Neurology, Renmin Hospital of Wuhan University, Wuhan, China
| | - Jiajia Yao
- Department of Neurology, Renmin Hospital of Wuhan University, Wuhan, China
| | - Rong Fu
- Department of Neurology, Renmin Hospital of Wuhan University, Wuhan, China
| | - Hang Yu
- Department of Neurology, Renmin Hospital of Wuhan University, Wuhan, China
| | - Zuneng Lu
- Department of Neurology, Renmin Hospital of Wuhan University, Wuhan, China.
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10
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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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11
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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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12
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Sontag EM, Morales-Polanco F, Chen JH, McDermott G, Dolan PT, Gestaut D, Le Gros MA, Larabell C, Frydman J. Nuclear and cytoplasmic spatial protein quality control is coordinated by nuclear-vacuolar junctions and perinuclear ESCRT. Nat Cell Biol 2023; 25:699-713. [PMID: 37081164 DOI: 10.1038/s41556-023-01128-6] [Citation(s) in RCA: 19] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2020] [Accepted: 03/14/2023] [Indexed: 04/22/2023]
Abstract
Effective protein quality control (PQC), essential for cellular health, relies on spatial sequestration of misfolded proteins into defined inclusions. Here we reveal the coordination of nuclear and cytoplasmic spatial PQC. Cytoplasmic misfolded proteins concentrate in a cytoplasmic juxtanuclear quality control compartment, while nuclear misfolded proteins sequester into an intranuclear quality control compartment (INQ). Particle tracking reveals that INQ and the juxtanuclear quality control compartment converge to face each other across the nuclear envelope at a site proximal to the nuclear-vacuolar junction marked by perinuclear ESCRT-II/III protein Chm7. Strikingly, convergence at nuclear-vacuolar junction contacts facilitates VPS4-dependent vacuolar clearance of misfolded cytoplasmic and nuclear proteins, the latter entailing extrusion of nuclear INQ into the vacuole. Finding that nuclear-vacuolar contact sites are cellular hubs of spatial PQC to facilitate vacuolar clearance of nuclear and cytoplasmic inclusions highlights the role of cellular architecture in proteostasis maintenance.
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Affiliation(s)
- Emily M Sontag
- Department of Biology, Stanford University, Stanford, CA, USA.
- Department of Biological Sciences, Marquette University, Milwaukee, WI, USA.
| | | | - Jian-Hua Chen
- Department of Anatomy, School of Medicine, University of California San Francisco, San Francisco, CA, USA
| | - Gerry McDermott
- Department of Anatomy, School of Medicine, University of California San Francisco, San Francisco, CA, USA
| | - Patrick T Dolan
- Department of Biology, Stanford University, Stanford, CA, USA
- Quantitative Virology and Evolution Unit, National Institute of Allergy and Infectious Diseases, Bethesda, MD, USA
| | - Daniel Gestaut
- Department of Biology, Stanford University, Stanford, CA, USA
| | - Mark A Le Gros
- Department of Anatomy, School of Medicine, University of California San Francisco, San Francisco, CA, USA
- Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | - Carolyn Larabell
- Department of Anatomy, School of Medicine, University of California San Francisco, San Francisco, CA, USA
- Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | - Judith Frydman
- Department of Biology, Stanford University, Stanford, CA, USA.
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13
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McGoldrick P, Lau A, You Z, Durcan TM, Robertson J. Loss of C9orf72 perturbs the Ran-GTPase gradient and nucleocytoplasmic transport, generating compositionally diverse Importin β-1 granules. Cell Rep 2023; 42:112134. [PMID: 36821445 DOI: 10.1016/j.celrep.2023.112134] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2021] [Revised: 10/05/2022] [Accepted: 01/31/2023] [Indexed: 02/24/2023] Open
Abstract
A hexanucleotide (GGGGCC)n repeat expansion in C9orf72 causes amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD), eliciting toxic effects through generation of RNA foci, dipeptide repeat proteins, and/or loss of C9orf72 protein. Defects in nucleocytoplasmic transport (NCT) have been implicated as a pathogenic mechanism underlying repeat expansion toxicity. Here, we show that loss of C9orf72 disrupts the Ran-GTPase gradient and NCT in vitro and in vivo. NCT disruption in vivo is enhanced by the presence of compositionally different types of cytoplasmic Importin β-1 granule that exhibit neuronal subtype-specific properties. We show that the abundance of Importin β-1 granules is increased in the context of C9orf72 deficiency, disrupting interactions with nuclear pore complex proteins. These granules appear to associate with the nuclear envelope and are co-immunoreactive for G3BP1 and K63-ubiquitin. These findings link loss of C9orf72 protein to gain-of-function mechanisms and defects in NCT.
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Affiliation(s)
- Philip McGoldrick
- Tanz Centre for Research in Neurodegenerative Diseases, University of Toronto, 60 Leonard Avenue, Toronto, ON M5T 2S8, Canada.
| | - Agnes Lau
- Tanz Centre for Research in Neurodegenerative Diseases, University of Toronto, 60 Leonard Avenue, Toronto, ON M5T 2S8, Canada
| | - Zhipeng You
- The Neuro's Early Drug Discovery Unit (EDDU), McGill University, 3801 University Street, Montreal, QC H3A 2B4, Canada
| | - Thomas M Durcan
- The Neuro's Early Drug Discovery Unit (EDDU), McGill University, 3801 University Street, Montreal, QC H3A 2B4, Canada
| | - Janice Robertson
- Tanz Centre for Research in Neurodegenerative Diseases, University of Toronto, 60 Leonard Avenue, Toronto, ON M5T 2S8, Canada; Department of Laboratory Medicine and Pathobiology, 27 King's College Circle, Toronto, ON M5S 1A1, Canada.
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14
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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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15
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Spead O, Zaepfel BL, Rothstein JD. Nuclear Pore Dysfunction in Neurodegeneration. Neurotherapeutics 2022; 19:1050-1060. [PMID: 36070178 PMCID: PMC9587172 DOI: 10.1007/s13311-022-01293-w] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/23/2022] [Indexed: 10/14/2022] Open
Abstract
The nuclear pore complex (NPC) is a large multimeric structure that is interspersed throughout the membrane of the nucleus and consists of at least 33 protein components. Individual components cooperate within the nuclear pore to facilitate selective passage of materials between the nucleus and cytoplasm while simultaneously performing pore-independent roles throughout the cell. NPC dysfunction is a hallmark of neurodegenerative disorders including Alzheimer's disease, Huntington's disease, and amyotrophic lateral sclerosis (ALS). NPC components can become mislocalized or altered in expression in neurodegeneration. These alterations in NPC structure are often detrimental to the neuronal function and ultimately lead to neuronal loss. This review highlights the importance of nucleocytoplasmic transport and NPC integrity and how dysfunction of such may contribute to neurodegeneration.
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Affiliation(s)
- Olivia Spead
- 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
| | - Benjamin L Zaepfel
- 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
| | - 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.
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16
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Goutman SA, Hardiman O, Al-Chalabi A, Chió A, Savelieff MG, Kiernan MC, Feldman EL. Emerging insights into the complex genetics and pathophysiology of amyotrophic lateral sclerosis. Lancet Neurol 2022; 21:465-479. [PMID: 35334234 PMCID: PMC9513754 DOI: 10.1016/s1474-4422(21)00414-2] [Citation(s) in RCA: 126] [Impact Index Per Article: 63.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2021] [Revised: 10/21/2021] [Accepted: 11/15/2021] [Indexed: 12/11/2022]
Abstract
Amyotrophic lateral sclerosis is a fatal neurodegenerative disease. The discovery of genes associated with amyotrophic lateral sclerosis, commencing with SOD1 in 1993, started fairly gradually. Recent advances in genetic technology have led to the rapid identification of multiple new genes associated with the disease, and to a new understanding of oligogenic and polygenic disease risk. The overlap of genes associated with amyotrophic lateral sclerosis with those of other neurodegenerative diseases is shedding light on the phenotypic spectrum of neurodegeneration, leading to a better understanding of genotype-phenotype correlations. A deepening knowledge of the genetic architecture is allowing the characterisation of the molecular steps caused by various mutations that converge on recurrent dysregulated pathways. Of crucial relevance, mutations associated with amyotrophic lateral sclerosis are amenable to novel gene-based therapeutic options, an approach in use for other neurological illnesses. Lastly, the exposome-the summation of lifetime environmental exposures-has emerged as an influential component for amyotrophic lateral sclerosis through the gene-time-environment hypothesis. Our improved understanding of all these aspects will lead to long-awaited therapies and the identification of modifiable risks factors.
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Affiliation(s)
| | - Orla Hardiman
- Academic Unit of Neurology, Trinity Biomedical Sciences Institute, Trinity College Dublin, Dublin, Ireland
| | - Ammar Al-Chalabi
- Department of Basic and Clinical Neuroscience, Maurice Wohl Clinical Neuroscience Institute, and Department of Neurology, King's College London, London, UK
| | - Adriano Chió
- Rita Levi Montalcini Department of Neurosciences, University of Turin, Turin, Italy
| | | | - Matthew C Kiernan
- Brain and Mind Centre, University of Sydney, Sydney, NSW, Australia; Department of Neurology, Royal Prince Alfred Hospital, Sydney, NSW, Australia
| | - Eva L Feldman
- Department of Neurology, University of Michigan, Ann Arbor, MI, USA.
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17
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Bindra D, Mishra RK. In Pursuit of Distinctiveness: Transmembrane Nucleoporins and Their Disease Associations. Front Oncol 2022; 11:784319. [PMID: 34970494 PMCID: PMC8712647 DOI: 10.3389/fonc.2021.784319] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2021] [Accepted: 11/25/2021] [Indexed: 11/13/2022] Open
Abstract
The bi-directional nucleocytoplasmic shuttling of macromolecules like molecular signals, transcription factors, regulatory proteins, and RNAs occurs exclusively through Nuclear Pore Complex (NPC) residing in the nuclear membrane. This magnanimous complex is essentially a congregation of ~32 conserved proteins termed Nucleoporins (Nups) present in multiple copies and mostly arranged as subcomplexes to constitute a functional NPC. Nups participate in ancillary functions such as chromatin organization, transcription regulation, DNA damage repair, genome stabilization, and cell cycle control, apart from their central role as nucleocytoplasmic conduits. Thus, Nups exert a role in the maintenance of cellular homeostasis. In mammals, precisely three nucleoporins traverse the nuclear membrane, are called transmembrane Nups (TM-Nups), and are involved in multiple cellular functions. Owing to their vital roles in cellular processes and homeostasis, dysregulation of nucleoporin function is implicated in various diseases. The deregulated functioning of TM-Nups can thus act as an opportune window for the development of diseases. Indeed, mounting evidence exhibits a strong association of TM-Nups in cancer and numerous other physiological disorders. These findings have provided much-needed insights into the novel mechanisms of disease progression. While nucleoporin’s functions have often been summarized in the disease context, a focus on TM-Nups has always lacked. This review emphasizes the elucidation of distinct canonical and non-canonical functions of mammalian TM-Nups and the underlying mechanisms of their disease association.
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Affiliation(s)
- Divya Bindra
- Nups and SUMO Biology Group, Department of Biological Sciences, Indian Institute of Science Education and Research (IISER) Bhopal, Bhopal, India
| | - Ram Kumar Mishra
- Nups and SUMO Biology Group, Department of Biological Sciences, Indian Institute of Science Education and Research (IISER) Bhopal, Bhopal, India
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18
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Vanneste J, Van Den Bosch L. The Role of Nucleocytoplasmic Transport Defects in Amyotrophic Lateral Sclerosis. Int J Mol Sci 2021; 22:12175. [PMID: 34830069 PMCID: PMC8620263 DOI: 10.3390/ijms222212175] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2021] [Revised: 10/10/2021] [Accepted: 10/14/2021] [Indexed: 12/24/2022] Open
Abstract
There is ample evidence that nucleocytoplasmic-transport deficits could play an important role in the pathology of amyotrophic lateral sclerosis (ALS). However, the currently available data are often circumstantial and do not fully clarify the exact causal and temporal role of nucleocytoplasmic transport deficits in ALS patients. Gaining this knowledge will be of great significance in order to be able to target therapeutically nucleocytoplasmic transport and/or the proteins involved in this process. The availability of good model systems to study the nucleocytoplasmic transport process in detail will be especially crucial in investigating the effect of different mutations, as well as of other forms of stress. In this review, we discuss the evidence for the involvement of nucleocytoplasmic transport defects in ALS and the methods used to obtain these data. In addition, we provide an overview of the therapeutic strategies which could potentially counteract these defects.
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Affiliation(s)
- Joni Vanneste
- Experimental Neurology, Department of Neurosciences and Leuven Brain Institute (LBI), KU Leuven–University of Leuven, B-3000 Leuven, Belgium;
- Laboratory of Neurobiology, Center for Brain & Disease Research, VIB, B-3000 Leuven, Belgium
| | - Ludo Van Den Bosch
- Experimental Neurology, Department of Neurosciences and Leuven Brain Institute (LBI), KU Leuven–University of Leuven, B-3000 Leuven, Belgium;
- Laboratory of Neurobiology, Center for Brain & Disease Research, VIB, B-3000 Leuven, Belgium
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19
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Liu YJ, Kuo HC, Chern Y. A system-wide mislocalization of RNA-binding proteins in motor neurons is a new feature of ALS. Neurobiol Dis 2021; 160:105531. [PMID: 34634461 DOI: 10.1016/j.nbd.2021.105531] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2021] [Revised: 09/28/2021] [Accepted: 10/07/2021] [Indexed: 01/01/2023] Open
Abstract
Amyotrophic lateral sclerosis (ALS) is a motor neuron disease characterized by progressive degeneration of motor neurons. Mislocalization of TAR DNA-binding protein 43 (TDP-43) is an early event in the formation of cytoplasmic TDP-43-positive inclusions in motor neurons and a hallmark of ALS. However, the underlying mechanism and the pathogenic impact of this mislocalization are relatively unexplored. We previously reported that abnormal AMPK activation mediates TDP-43 mislocalization in motor neurons of humans and mice with ALS. In the present study, we hypothesized that other nuclear proteins are mislocalized in the cytoplasm of motor neurons due to the AMPK-mediated phosphorylation of importin-α1 and subsequently contribute to neuronal degeneration in ALS. To test this hypothesis, we analyzed motor neurons of sporadic ALS patients and found that when AMPK is activated, importin-α1 is abnormally located in the nucleus. Multiple integrative molecular and cellular approaches (including proteomics, immunoprecipitation/western blot analysis, immunohistological evaluations and gradient analysis of preribosomal complexes) were employed to demonstrate that numerous RNA binding proteins are mislocalized in a rodent motor neuron cell line (NSC34) and human motor neurons derived from iPSCs during AMPK activation. We used comparative proteomic analysis of importin-α1 complexes that were immunoprecipitated with a phosphorylation-deficient mutant of importin-α1 (importin-α1-S105A) and a phosphomimetic mutant of importin-α1 (importin-α1-S105D) to identify 194 proteins that have stronger affinity for the unphosphorylated form than the phosphorylated form of importin-α1. Furthermore, GO and STRING analyses suggested that RNA processing and protein translation is the major machinery affected by abnormalities in the AMPK-importin-α1 axis. Consistently, the expression of importin-α1-S105D alters the assembly of preribosomal complexes and increases cell apoptosis. Collectively, we propose that by impairing importin-α1-mediated nuclear import, abnormal AMPK activation in motor neurons alters the cellular distribution of many RNA-binding proteins, which pathogenically affect multiple cellular machineries in motor neurons and contribute to ALS pathogenesis.
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Affiliation(s)
- Yu-Ju Liu
- Division of Neuroscience, Institute of Biomedical Sciences, Academia Sinica, Taipei, Taiwan
| | - Hung-Chih Kuo
- Institute of Cellular and Organismic Biology, Academia Sinica, Taipei, Taiwan
| | - Yijuang Chern
- Division of Neuroscience, Institute of Biomedical Sciences, Academia Sinica, Taipei, Taiwan.
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20
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Diez L, Wegmann S. Nuclear Transport Deficits in Tau-Related Neurodegenerative Diseases. Front Neurol 2020; 11:1056. [PMID: 33101165 PMCID: PMC7546323 DOI: 10.3389/fneur.2020.01056] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2020] [Accepted: 08/11/2020] [Indexed: 12/14/2022] Open
Abstract
Tau is a cytosolic microtubule binding protein that is highly abundant in the axons of the central nervous system. However, alternative functions of tau also in other cellular compartments are suggested, for example, in the nucleus, where interactions of tau with specific nuclear entities such as DNA, the nucleolus, and the nuclear envelope have been reported. We would like to review the current knowledge about tau-nucleus interactions and lay out possible neurotoxic mechanisms that are based on the (pathological) interactions of tau with the nucleus.
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Affiliation(s)
- Lisa Diez
- German Center for Neurodegenerative Diseases, Berlin, Germany
| | - Susanne Wegmann
- German Center for Neurodegenerative Diseases, Berlin, Germany
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21
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Fallini C, Khalil B, Smith CL, Rossoll W. Traffic jam at the nuclear pore: All roads lead to nucleocytoplasmic transport defects in ALS/FTD. Neurobiol Dis 2020; 140:104835. [PMID: 32179176 DOI: 10.1016/j.nbd.2020.104835] [Citation(s) in RCA: 37] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2019] [Revised: 01/25/2020] [Accepted: 03/12/2020] [Indexed: 02/06/2023] Open
Abstract
Amyotrophic lateral sclerosis (ALS) is a fatal late-onset neurodegenerative disease that specifically affects the function and survival of spinal and cortical motor neurons. ALS shares many genetic, clinical, and pathological characteristics with frontotemporal dementia (FTD), and these diseases are now recognized as presentations of a disease spectrum known as ALS/FTD. The molecular determinants of neuronal loss in ALS/FTD are still debated, but the recent discovery of nucleocytoplasmic transport defects as a common denominator of most if not all forms of ALS/FTD has dramatically changed our understanding of the pathogenic mechanisms of this disease. Loss of nuclear pores and nucleoporin aggregation, altered nuclear morphology, and impaired nuclear transport are some of the most prominent features that have been identified using a variety of animal, cellular, and human models of disease. Here, we review the experimental evidence linking nucleocytoplasmic transport defects to the pathogenesis of ALS/FTD and propose a unifying view on how these defects may lead to a vicious cycle that eventually causes neuronal death.
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Affiliation(s)
- Claudia Fallini
- George and Anne Ryan Institute for Neuroscience, University of Rhode Island, Kingston, RI 02881, USA; Department of Cell and Molecular Biology, University of Rhode Island, Kingston, RI 02881, USA; Department of Biomedical and Pharmaceutical Sciences, University of Rhode Island, Kingston, RI 02881, USA.
| | - Bilal Khalil
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL 32224, USA
| | - Courtney L Smith
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL 32224, USA
| | - Wilfried Rossoll
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL 32224, USA.
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22
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Hutten S, Dormann D. Nucleocytoplasmic transport defects in neurodegeneration — Cause or consequence? Semin Cell Dev Biol 2020; 99:151-162. [DOI: 10.1016/j.semcdb.2019.05.020] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2019] [Revised: 05/21/2019] [Accepted: 05/21/2019] [Indexed: 12/12/2022]
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23
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Moore S, Rabichow BE, Sattler R. The Hitchhiker's Guide to Nucleocytoplasmic Trafficking in Neurodegeneration. Neurochem Res 2020; 45:1306-1327. [PMID: 32086712 DOI: 10.1007/s11064-020-02989-1] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2019] [Revised: 02/12/2020] [Accepted: 02/14/2020] [Indexed: 12/12/2022]
Abstract
The widespread nature of nucleocytoplasmic trafficking defects and protein accumulation suggests distinct yet overlapping mechanisms in a variety of neurodegenerative diseases. Detailed understanding of the cellular pathways involved in nucleocytoplasmic transport and its dysregulation are essential for elucidating neurodegenerative pathogenesis and pinpointing potential areas for therapeutic intervention. The transport of cargos from the nucleus to the cytoplasm is generally regulated by the structure and function of the nuclear pore as well as the karyopherin α/β, importin, exportin, and mRNA export mechanisms. The disruption of these crucial transport mechanisms has been extensively described in the context of neurodegenerative diseases. One common theme in neurodegeneration is the cytoplasmic aggregation of proteins, including nuclear RNA binding proteins, repeat expansion associated gene products, and tau. These cytoplasmic aggregations are partly a consequence of failed nucleocytoplasmic transport machinery, but can also further disrupt transport, creating cyclical feed-forward mechanisms that exacerbate neurodegeneration. Here we describe the canonical mechanisms that regulate nucleocytoplasmic trafficking as well as how these mechanisms falter in neurodegenerative diseases.
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Affiliation(s)
- Stephen Moore
- Department of Neurobiology, Barrow Neurological Institute, 350 W Thomas Road, Phoenix, AZ, 85013, USA.,School of Life Sciences, Arizona State University, Tempe, AZ, USA
| | - Benjamin E Rabichow
- Department of Neurobiology, Barrow Neurological Institute, 350 W Thomas Road, Phoenix, AZ, 85013, USA
| | - Rita Sattler
- Department of Neurobiology, Barrow Neurological Institute, 350 W Thomas Road, Phoenix, AZ, 85013, USA.
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24
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Spannl S, Tereshchenko M, Mastromarco GJ, Ihn SJ, Lee HO. Biomolecular condensates in neurodegeneration and cancer. Traffic 2019; 20:890-911. [PMID: 31606941 DOI: 10.1111/tra.12704] [Citation(s) in RCA: 56] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2019] [Revised: 10/03/2019] [Accepted: 10/06/2019] [Indexed: 12/14/2022]
Abstract
The intracellular environment is partitioned into functionally distinct compartments containing specific sets of molecules and reactions. Biomolecular condensates, also referred to as membrane-less organelles, are diverse and abundant cellular compartments that lack membranous enclosures. Molecules assemble into condensates by phase separation; multivalent weak interactions drive molecules to separate from their surroundings and concentrate in discrete locations. Biomolecular condensates exist in all eukaryotes and in some prokaryotes, and participate in various essential house-keeping, stress-response and cell type-specific processes. An increasing number of recent studies link abnormal condensate formation, composition and material properties to a number of disease states. In this review, we discuss current knowledge and models describing the regulation of condensates and how they become dysregulated in neurodegeneration and cancer. Further research on the regulation of biomolecular phase separation will help us to better understand their role in cell physiology and disease.
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Affiliation(s)
- Stephanie Spannl
- Department of Biochemistry, University of Toronto, Toronto, Ontario, Canada
| | - Maria Tereshchenko
- Department of Biochemistry, University of Toronto, Toronto, Ontario, Canada
| | | | - Sean J Ihn
- Department of Biochemistry, University of Toronto, Toronto, Ontario, Canada
| | - Hyun O Lee
- Department of Biochemistry, University of Toronto, Toronto, Ontario, Canada
- Canada Research Chairs Program, University of Toronto, Toronto, Ontario, Canada
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25
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Cho KI, Yoon D, Yu M, Peachey NS, Ferreira PA. Microglial activation in an amyotrophic lateral sclerosis-like model caused by Ranbp2 loss and nucleocytoplasmic transport impairment in retinal ganglion neurons. Cell Mol Life Sci 2019; 76:3407-3432. [PMID: 30944974 PMCID: PMC6698218 DOI: 10.1007/s00018-019-03078-5] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2018] [Revised: 02/21/2019] [Accepted: 03/18/2019] [Indexed: 12/12/2022]
Abstract
Nucleocytoplasmic transport is dysregulated in sporadic and familial amyotrophic lateral sclerosis (ALS) and retinal ganglion neurons (RGNs) are purportedly involved in ALS. The Ran-binding protein 2 (Ranbp2) controls rate-limiting steps of nucleocytoplasmic transport. Mice with Ranbp2 loss in Thy1+-motoneurons develop cardinal ALS-like motor traits, but the impairments in RGNs and the degree of dysfunctional consonance between RGNs and motoneurons caused by Ranbp2 loss are unknown. This will help to understand the role of nucleocytoplasmic transport in the differential vulnerability of neuronal cell types to ALS and to uncover non-motor endophenotypes with pathognomonic signs of ALS. Here, we ascertain Ranbp2's function and endophenotypes in RGNs of an ALS-like mouse model lacking Ranbp2 in motoneurons and RGNs. Thy1+-RGNs lacking Ranbp2 shared with motoneurons the dysregulation of nucleocytoplasmic transport. RGN abnormalities were comprised morphologically by soma hypertrophy and optic nerve axonopathy and physiologically by a delay of the visual pathway's evoked potentials. Whole-transcriptome analysis showed restricted transcriptional changes in optic nerves that were distinct from those found in sciatic nerves. Specifically, the level and nucleocytoplasmic partition of the anti-apoptotic and novel substrate of Ranbp2, Pttg1/securin, were dysregulated. Further, acetyl-CoA carboxylase 1, which modulates de novo synthesis of fatty acids and T-cell immunity, showed the highest up-regulation (35-fold). This effect was reflected by the activation of ramified CD11b+ and CD45+-microglia, increase of F4\80+-microglia and a shift from pseudopodial/lamellipodial to amoeboidal F4\80+-microglia intermingled between RGNs of naive mice. Further, there was the intracellular sequestration in RGNs of metalloproteinase-28, which regulates macrophage recruitment and polarization in inflammation. Hence, Ranbp2 genetic insults in RGNs and motoneurons trigger distinct paracrine signaling likely by the dysregulation of nucleocytoplasmic transport of neuronal-type selective substrates. Immune-modulators underpinning RGN-to-microglial signaling are regulated by Ranbp2, and this neuronal-glial system manifests endophenotypes that are likely useful in the prognosis and diagnosis of motoneuron diseases, such as ALS.
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Affiliation(s)
- Kyoung-In Cho
- Department of Ophthalmology, Duke University Medical Center, DUEC 3802, 2351 Erwin Road, Durham, NC, 27710, USA
| | - Dosuk Yoon
- Department of Ophthalmology, Duke University Medical Center, DUEC 3802, 2351 Erwin Road, Durham, NC, 27710, USA
| | - Minzhong Yu
- Department of Ophthalmic Research, Cole Eye Institute, Cleveland Clinic Foundation, Cleveland, OH, 44195, USA
- Department of Ophthalmology, Cleveland Clinic Lerner College of Medicine of Case Western Reserve University, Cleveland, OH, 44195, USA
| | - Neal S Peachey
- Department of Ophthalmic Research, Cole Eye Institute, Cleveland Clinic Foundation, Cleveland, OH, 44195, USA
- Research Service, Louis Stokes Cleveland Veterans Affairs Medical Center, Cleveland, OH, 44106, USA
- Department of Ophthalmology, Cleveland Clinic Lerner College of Medicine of Case Western Reserve University, Cleveland, OH, 44195, USA
| | - Paulo A Ferreira
- Department of Ophthalmology, Duke University Medical Center, DUEC 3802, 2351 Erwin Road, Durham, NC, 27710, USA.
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26
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Sun J, Shi Y, Yildirim E. The Nuclear Pore Complex in Cell Type-Specific Chromatin Structure and Gene Regulation. Trends Genet 2019; 35:579-588. [PMID: 31213386 DOI: 10.1016/j.tig.2019.05.006] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2019] [Revised: 05/15/2019] [Accepted: 05/16/2019] [Indexed: 12/14/2022]
Abstract
Nuclear pore complex (NPC)-mediated nucleocytoplasmic trafficking is essential for key cellular processes, such as cell growth, cell differentiation, and gene regulation. The NPC has also been viewed as a nuclear architectural platform that impacts genome function and gene expression by mediating spatial and temporal coordination between transcription factors, chromatin regulatory proteins, and transcription machinery. Recent findings have uncovered differential and cell type-specific expression and distinct chromatin-binding patterns of individual NPC components known as nucleoporins (Nups). Here, we examine recent studies that investigate the functional roles of NPCs and Nups in transcription, chromatin organization, and epigenetic gene regulation in the context of development and disease.
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Affiliation(s)
- Jiayu Sun
- Department of Cell Biology, Duke University School of Medicine, Durham, NC 27710, USA; Duke Cancer Institute, Durham, NC 27710, USA
| | - Yuming Shi
- Department of Cell Biology, Duke University School of Medicine, Durham, NC 27710, USA; Duke Cancer Institute, Durham, NC 27710, USA
| | - Eda Yildirim
- Department of Cell Biology, Duke University School of Medicine, Durham, NC 27710, USA; Duke Cancer Institute, Durham, NC 27710, USA.
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27
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Donnaloja F, Jacchetti E, Soncini M, Raimondi MT. Mechanosensing at the Nuclear Envelope by Nuclear Pore Complex Stretch Activation and Its Effect in Physiology and Pathology. Front Physiol 2019; 10:896. [PMID: 31354529 PMCID: PMC6640030 DOI: 10.3389/fphys.2019.00896] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2019] [Accepted: 06/27/2019] [Indexed: 02/03/2023] Open
Abstract
Cell fate is correlated to mechanotransduction, in which forces transmitted by the cytoskeleton filaments alter the nuclear shape, affecting transcription factor import/export, cells transcription activity and chromatin distribution. There is in fact evidence that stem cells cultured in 3D environments mimicking the native niche are able to maintain their stemness or modulate their cellular function. However, the molecular and biophysical mechanisms underlying cellular mechanosensing are still largely unclear. The propagation of mechanical stimuli via a direct pathway from cell membrane integrins to SUN proteins residing in the nuclear envelop has been demonstrated, but we suggest that the cells’ fate is mainly affected by the force distribution at the nuclear envelope level, where the SUN protein transmits the stimuli via its mechanical connection to several cell structures such as chromatin, lamina and the nuclear pore complex (NPC). In this review, we analyze the NPC structure and organization, which have not as yet been fully investigated, and its plausible involvement in cell fate. NPC is a multiprotein complex that spans the nuclear envelope, and is involved in several key cellular processes such as bidirectional nucleocytoplasmic exchange, cell cycle regulation, kinetochore organization, and regulation of gene expression. As several connections between the NPC and the nuclear envelope, chromatin and other transmembrane proteins have been identified, it is reasonable to suppose that nuclear deformations can alter the NPC structure. We provide evidence that the transmission of mechanical forces may significantly affects the basket conformation via the Nup153-SUN1 connection, both altering the passage of molecules through it and influencing the state of chromatin packing. Finally, we review the known correlations between a pathological NPC structure and diseases such as cancer, autoimmune disease, aging and laminopathies.
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Affiliation(s)
- F Donnaloja
- Department of Chemistry, Materials and Chemical Engineering "Giulio Natta," Politecnico di Milano, Milan, Italy
| | - E Jacchetti
- Department of Chemistry, Materials and Chemical Engineering "Giulio Natta," Politecnico di Milano, Milan, Italy
| | - M Soncini
- Department of Electronics, Information and Bioengineering, Politecnico di Milano, Milan, Italy
| | - M T Raimondi
- Department of Chemistry, Materials and Chemical Engineering "Giulio Natta," Politecnico di Milano, Milan, Italy
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28
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Burk K, Pasterkamp RJ. Disrupted neuronal trafficking in amyotrophic lateral sclerosis. Acta Neuropathol 2019; 137:859-877. [PMID: 30721407 PMCID: PMC6531423 DOI: 10.1007/s00401-019-01964-7] [Citation(s) in RCA: 94] [Impact Index Per Article: 18.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2018] [Revised: 01/19/2019] [Accepted: 01/19/2019] [Indexed: 02/07/2023]
Abstract
Amyotrophic lateral sclerosis (ALS) is a progressive, adult-onset neurodegenerative disease caused by degeneration of motor neurons in the brain and spinal cord leading to muscle weakness. Median survival after symptom onset in patients is 3-5 years and no effective therapies are available to treat or cure ALS. Therefore, further insight is needed into the molecular and cellular mechanisms that cause motor neuron degeneration and ALS. Different ALS disease mechanisms have been identified and recent evidence supports a prominent role for defects in intracellular transport. Several different ALS-causing gene mutations (e.g., in FUS, TDP-43, or C9ORF72) have been linked to defects in neuronal trafficking and a picture is emerging on how these defects may trigger disease. This review summarizes and discusses these recent findings. An overview of how endosomal and receptor trafficking are affected in ALS is followed by a description on dysregulated autophagy and ER/Golgi trafficking. Finally, changes in axonal transport and nucleocytoplasmic transport are discussed. Further insight into intracellular trafficking defects in ALS will deepen our understanding of ALS pathogenesis and will provide novel avenues for therapeutic intervention.
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Affiliation(s)
- Katja Burk
- Department of Neurologie, Universitätsmedizin Göttingen, Robert-Koch-Str. 40, 37075, Göttingen, Germany.
- Center for Biostructural Imaging of Neurodegeneration, Von-Siebold-Str. 3A, 37075, Göttingen, Germany.
| | - R Jeroen Pasterkamp
- Department of Translational Neuroscience, UMC Utrecht Brain Center, University Medical Center Utrecht, Utrecht University, Universiteitsweg 100, 3584 CG, Utrecht, The Netherlands.
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29
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Ferreira PA. The coming-of-age of nucleocytoplasmic transport in motor neuron disease and neurodegeneration. Cell Mol Life Sci 2019; 76:2247-2273. [PMID: 30742233 PMCID: PMC6531325 DOI: 10.1007/s00018-019-03029-0] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2018] [Accepted: 01/28/2019] [Indexed: 12/11/2022]
Abstract
The nuclear pore is the gatekeeper of nucleocytoplasmic transport and signaling through which a vast flux of information is continuously exchanged between the nuclear and cytoplasmic compartments to maintain cellular homeostasis. A unifying and organizing principle has recently emerged that cements the notion that several forms of amyotrophic lateral sclerosis (ALS), and growing number of other neurodegenerative diseases, co-opt the dysregulation of nucleocytoplasmic transport and that this impairment is a pathogenic driver of neurodegeneration. The understanding of shared pathomechanisms that underpin neurodegenerative diseases with impairments in nucleocytoplasmic transport and how these interface with current concepts of nucleocytoplasmic transport is bound to illuminate this fundamental biological process in a yet more physiological context. Here, I summarize unresolved questions and evidence and extend basic and critical concepts and challenges of nucleocytoplasmic transport and its role in the pathogenesis of neurodegenerative diseases, such as ALS. These principles will help to appreciate the roles of nucleocytoplasmic transport in the pathogenesis of ALS and other neurodegenerative diseases, and generate a framework for new ideas of the susceptibility of motoneurons, and possibly other neurons, to degeneration by dysregulation of nucleocytoplasmic transport.
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Affiliation(s)
- Paulo A Ferreira
- Duke University Medical Center, DUEC 3802, 2351 Erwin Road, Durham, NC, 27710, USA.
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30
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Benarroch EE. Nucleocytoplasmic transport: Mechanisms and involvement in neurodegenerative disease. Neurology 2019; 92:757-764. [PMID: 30894450 DOI: 10.1212/wnl.0000000000007305] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
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31
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Suresh S, Osmani SA. Poring over chromosomes: mitotic nuclear pore complex segregation. Curr Opin Cell Biol 2019; 58:42-49. [PMID: 30798206 DOI: 10.1016/j.ceb.2019.01.002] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2018] [Revised: 01/09/2019] [Accepted: 01/18/2019] [Indexed: 01/23/2023]
Abstract
Eukaryotic cells rely on flux of macromolecules between the nucleus and the cytoplasm for growth and survival. Bidirectional transport is achieved through Nuclear Pore Complexes (NPCs) embedded in the Nuclear Envelope (NE). NPC proteins perform other cellular functions during mitosis, chromatin organization, DNA repair and gene regulation. Dysregulation of NPC number, or defects in their structure and function, are linked to numerous diseases but how NPCs are faithfully inherited during mitosis is poorly understood. In this review, we discuss recent insights to mechanisms of mammalian mitotic NPC segregation and NPC assembly as well as mitotic NPC inheritance via the mitotic chromatin located NPC protein Nup2 in Aspergillus nidulans. We suggest mitotic Nup2 chromatin-based mechanisms could also operate in vertebrate cells.
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Affiliation(s)
- Subbulakshmi Suresh
- Department of Molecular Genetics, The Ohio State University, 484 West 12th Avenue, Columbus, OH 43210, USA.
| | - Stephen A Osmani
- Department of Molecular Genetics, The Ohio State University, 484 West 12th Avenue, Columbus, OH 43210, USA
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32
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Fahrenkrog B, Harel A. Perturbations in Traffic: Aberrant Nucleocytoplasmic Transport at the Heart of Neurodegeneration. Cells 2018; 7:cells7120232. [PMID: 30486313 PMCID: PMC6316434 DOI: 10.3390/cells7120232] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2018] [Revised: 11/22/2018] [Accepted: 11/23/2018] [Indexed: 12/25/2022] Open
Abstract
Neurodegenerative diseases, such as amyotrophic lateral sclerosis (ALS), frontotemporal dementia (FTD), and Huntington’s disease (HD), are characterized by intracellular aggregation of proteins. In the case of ALS and FTD, these protein aggregates are found in the cytoplasm of affected neurons and contain certain RNA-binding proteins (RBPs), namely the TAR DNA-binding protein of 43 kDa (TDP-43) and the fused in sarcoma (FUS) gene product. TDP-43 and FUS are nuclear proteins and their displacement to the cytoplasm is thought to be adverse in at least two ways: loss-of-function in the nucleus and gain-of-toxicity in the cytoplasm. In the case of HD, expansion of a polyglutamine (polyQ) stretch within the N-terminal domain of the Huntingtin (HTT) protein leads to nuclear accumulation of polyQ HTT (or mHTT) and a toxic gain-of-function phenotype resulting in neurodegeneration. Numerous studies in recent years have provided evidence that defects in nucleocytoplasmic transport critically contribute to the pathology of these neurodegenerative diseases. A new mechanistic view is emerging, implicating three types of perturbations in normal cellular pathways that rely on nucleocytoplasmic transport: displacement of nuclear transport receptors and nucleoporins from nuclear pore complexes (NPCs), mislocalization and aggregation of RNA-binding proteins, and weakening of the chaperone activity of nuclear import receptors.
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Affiliation(s)
- Birthe Fahrenkrog
- Institute of Molecular Biology and Medicine, Université Libre de Bruxelles, 6041 Charleroi, Belgium.
| | - Amnon Harel
- Azrieli Faculty of Medicine, Bar-Ilan University, Safed 1311502, Israel.
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33
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Boehringer A, Bowser R. RNA Nucleocytoplasmic Transport Defects in Neurodegenerative Diseases. ADVANCES IN NEUROBIOLOGY 2018; 20:85-101. [PMID: 29916017 DOI: 10.1007/978-3-319-89689-2_4] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
In eukaryotic cells, transcription and translation are compartmentalized by the nuclear membrane, requiring an active transport of RNA from the nucleus into the cytoplasm. This is accomplished by a variety of transport complexes that contain either a member of the exportin family of proteins and translocation fueled by GTP hydrolysis or in the case of mRNA by complexes containing the export protein NXF1. Recent evidence indicates that RNA transport is altered in a number of different neurodegenerative diseases including Huntington's disease, Alzheimer's disease, frontotemporal dementia, and amyotrophic lateral sclerosis. Alterations in RNA transport predominately fall into three categories: Alterations in the nuclear membrane and mislocalization and aggregation of the nucleoporins that make up the nuclear pore; alterations in the Ran gradient and the proteins that control it which impacts exportin based nuclear export; and alterations of proteins that are required for the export of mRNA leading nuclear accumulation of mRNA.
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Affiliation(s)
- Ashley Boehringer
- Department of Neurobiology, Barrow Neurological Institute, Phoenix, AZ, USA.,School of Life Sciences, Arizona State University, Phoenix, AZ, USA
| | - Robert Bowser
- Department of Neurobiology, Barrow Neurological Institute, Phoenix, AZ, USA.
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34
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Tank EM, Figueroa-Romero C, Hinder LM, Bedi K, Archbold HC, Li X, Weskamp K, Safren N, Paez-Colasante X, Pacut C, Thumma S, Paulsen MT, Guo K, Hur J, Ljungman M, Feldman EL, Barmada SJ. Abnormal RNA stability in amyotrophic lateral sclerosis. Nat Commun 2018; 9:2845. [PMID: 30030424 PMCID: PMC6054632 DOI: 10.1038/s41467-018-05049-z] [Citation(s) in RCA: 91] [Impact Index Per Article: 15.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2017] [Accepted: 06/11/2018] [Indexed: 12/11/2022] Open
Abstract
Amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD) share key features, including accumulation of the RNA-binding protein TDP-43. TDP-43 regulates RNA homeostasis, but it remains unclear whether RNA stability is affected in these disorders. We use Bru-seq and BruChase-seq to assess genome-wide RNA stability in ALS patient-derived cells, demonstrating profound destabilization of ribosomal and mitochondrial transcripts. This pattern is recapitulated by TDP-43 overexpression, suggesting a primary role for TDP-43 in RNA destabilization, and in postmortem samples from ALS and FTD patients. Proteomics and functional studies illustrate corresponding reductions in mitochondrial components and compensatory increases in protein synthesis. Collectively, these observations suggest that TDP-43 deposition leads to targeted RNA instability in ALS and FTD, and may ultimately cause cell death by disrupting energy production and protein synthesis pathways.
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Affiliation(s)
- E M Tank
- Department of Neurology, University of Michigan Medical School, Ann Arbor, MI, 48109, USA
| | - C Figueroa-Romero
- Department of Neurology, University of Michigan Medical School, Ann Arbor, MI, 48109, USA
| | - L M Hinder
- Department of Neurology, University of Michigan Medical School, Ann Arbor, MI, 48109, USA
| | - K Bedi
- Department of Radiation Oncology, University of Michigan Medical School, Ann Arbor, MI, 48109, USA
| | - H C Archbold
- Department of Neurology, University of Michigan Medical School, Ann Arbor, MI, 48109, USA
| | - X Li
- Department of Neurology, University of Michigan Medical School, Ann Arbor, MI, 48109, USA
| | - K Weskamp
- Department of Neurology, University of Michigan Medical School, Ann Arbor, MI, 48109, USA
| | - N Safren
- Department of Neurology, University of Michigan Medical School, Ann Arbor, MI, 48109, USA
| | - X Paez-Colasante
- Department of Neurology, University of Michigan Medical School, Ann Arbor, MI, 48109, USA
| | - C Pacut
- Department of Neurology, University of Michigan Medical School, Ann Arbor, MI, 48109, USA
| | - S Thumma
- Department of Neurology, University of Michigan Medical School, Ann Arbor, MI, 48109, USA
| | - M T Paulsen
- Department of Radiation Oncology, University of Michigan Medical School, Ann Arbor, MI, 48109, USA
| | - K Guo
- Department of Biomedical Sciences, School of Medicine and Health Sciences, University of North Dakota, Grand Forks, ND, 58202, USA
| | - J Hur
- Department of Biomedical Sciences, School of Medicine and Health Sciences, University of North Dakota, Grand Forks, ND, 58202, USA
| | - M Ljungman
- Department of Radiation Oncology, University of Michigan Medical School, Ann Arbor, MI, 48109, USA
- Cellular & Molecular Biology Program, University of Michigan Medical School, Ann Arbor, MI, 48109, USA
| | - E L Feldman
- Department of Neurology, University of Michigan Medical School, Ann Arbor, MI, 48109, USA
- Cellular & Molecular Biology Program, University of Michigan Medical School, Ann Arbor, MI, 48109, USA
- Neuroscience Graduate Program, University of Michigan Medical School, Ann Arbor, MI, 48109, USA
| | - S J Barmada
- Department of Neurology, University of Michigan Medical School, Ann Arbor, MI, 48109, USA.
- Cellular & Molecular Biology Program, University of Michigan Medical School, Ann Arbor, MI, 48109, USA.
- Neuroscience Graduate Program, University of Michigan Medical School, Ann Arbor, MI, 48109, USA.
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35
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Cox D, Raeburn C, Sui X, Hatters DM. Protein aggregation in cell biology: An aggregomics perspective of health and disease. Semin Cell Dev Biol 2018; 99:40-54. [PMID: 29753879 DOI: 10.1016/j.semcdb.2018.05.003] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2017] [Revised: 03/21/2018] [Accepted: 05/04/2018] [Indexed: 01/08/2023]
Abstract
Maintaining protein homeostasis (proteostasis) is essential for cellular health and is governed by a network of quality control machinery comprising over 800 genes. When proteostasis becomes imbalanced, proteins can abnormally aggregate or become mislocalized. Inappropriate protein aggregation and proteostasis imbalance are two of the central pathological features of common neurodegenerative diseases including Alzheimer, Parkinson, Huntington, and motor neuron diseases. How aggregation contributes to the pathogenic mechanisms of disease remains incompletely understood. Here, we integrate some of the key and emerging ideas as to how protein aggregation relates to imbalanced proteostasis with an emphasis on Huntington disease as our area of main expertise. We propose the term "aggregomics" be coined in reference to how aggregation of particular proteins concomitantly influences the spatial organization and protein-protein interactions of the surrounding proteome. Meta-analysis of aggregated interactomes from various published datasets reveals chaperones and RNA-binding proteins are common components across various disease contexts. We conclude with an examination of therapeutic avenues targeting proteostasis mechanisms.
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Affiliation(s)
- Dezerae Cox
- Department of Biochemistry and Molecular Biology, The University of Melbourne, Australia; Bio21 Molecular Science and Biotechnology Institute, Australia
| | - Candice Raeburn
- Department of Biochemistry and Molecular Biology, The University of Melbourne, Australia; Bio21 Molecular Science and Biotechnology Institute, Australia
| | - Xiaojing Sui
- Department of Biochemistry and Molecular Biology, The University of Melbourne, Australia; Bio21 Molecular Science and Biotechnology Institute, Australia
| | - Danny M Hatters
- Department of Biochemistry and Molecular Biology, The University of Melbourne, Australia; Bio21 Molecular Science and Biotechnology Institute, Australia.
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36
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Lin DH, Correia AR, Cai SW, Huber FM, Jette CA, Hoelz A. Structural and functional analysis of mRNA export regulation by the nuclear pore complex. Nat Commun 2018; 9:2319. [PMID: 29899397 PMCID: PMC5998080 DOI: 10.1038/s41467-018-04459-3] [Citation(s) in RCA: 42] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2017] [Accepted: 04/27/2018] [Indexed: 11/25/2022] Open
Abstract
The nuclear pore complex (NPC) controls the passage of macromolecules between the nucleus and cytoplasm, but how the NPC directly participates in macromolecular transport remains poorly understood. In the final step of mRNA export, the DEAD-box helicase DDX19 is activated by the nucleoporins Gle1, Nup214, and Nup42 to remove Nxf1•Nxt1 from mRNAs. Here, we report crystal structures of Gle1•Nup42 from three organisms that reveal an evolutionarily conserved binding mode. Biochemical reconstitution of the DDX19 ATPase cycle establishes that human DDX19 activation does not require IP6, unlike its fungal homologs, and that Gle1 stability affects DDX19 activation. Mutations linked to motor neuron diseases cause decreased Gle1 thermostability, implicating nucleoporin misfolding as a disease determinant. Crystal structures of human Gle1•Nup42•DDX19 reveal the structural rearrangements in DDX19 from an auto-inhibited to an RNA-binding competent state. Together, our results provide the foundation for further mechanistic analyses of mRNA export in humans. The export of mRNA to the cytosol depends on the nuclear pore complex (NPC) and the activation of the helicase DDX19, but their interplay in humans remains poorly understood. Here, the authors present a structural and functional analysis of DDX19 activation, revealing how the human NPC regulates mRNA export.
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Affiliation(s)
- Daniel H Lin
- Division of Chemistry and Chemical Engineering, California Institute of Technology, 1200 East California Boulevard, Pasadena, CA, 91125, USA
| | - Ana R Correia
- Division of Chemistry and Chemical Engineering, California Institute of Technology, 1200 East California Boulevard, Pasadena, CA, 91125, USA
| | - Sarah W Cai
- Division of Chemistry and Chemical Engineering, California Institute of Technology, 1200 East California Boulevard, Pasadena, CA, 91125, USA
| | - Ferdinand M Huber
- Division of Chemistry and Chemical Engineering, California Institute of Technology, 1200 East California Boulevard, Pasadena, CA, 91125, USA
| | - Claudia A Jette
- Division of Chemistry and Chemical Engineering, California Institute of Technology, 1200 East California Boulevard, Pasadena, CA, 91125, USA
| | - André Hoelz
- Division of Chemistry and Chemical Engineering, California Institute of Technology, 1200 East California Boulevard, Pasadena, CA, 91125, USA.
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37
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Gao FB, Almeida S, Lopez-Gonzalez R. Dysregulated molecular pathways in amyotrophic lateral sclerosis-frontotemporal dementia spectrum disorder. EMBO J 2017; 36:2931-2950. [PMID: 28916614 DOI: 10.15252/embj.201797568] [Citation(s) in RCA: 125] [Impact Index Per Article: 17.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2017] [Revised: 07/15/2017] [Accepted: 08/30/2017] [Indexed: 12/11/2022] Open
Abstract
Frontotemporal dementia (FTD), the second most common form of dementia in people under 65 years of age, is characterized by progressive atrophy of the frontal and/or temporal lobes. FTD overlaps extensively with the motor neuron disease amyotrophic lateral sclerosis (ALS), especially at the genetic level. Both FTD and ALS can be caused by many mutations in the same set of genes; the most prevalent of these mutations is a GGGGCC repeat expansion in the first intron of C9ORF72 As shown by recent intensive studies, some key cellular pathways are dysregulated in the ALS-FTD spectrum disorder, including autophagy, nucleocytoplasmic transport, DNA damage repair, pre-mRNA splicing, stress granule dynamics, and others. These exciting advances reveal the complexity of the pathogenic mechanisms of FTD and ALS and suggest promising molecular targets for future therapeutic interventions in these devastating disorders.
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Affiliation(s)
- Fen-Biao Gao
- Department of Neurology, University of Massachusetts Medical School, Worcester, MA, USA
| | - Sandra Almeida
- Department of Neurology, University of Massachusetts Medical School, Worcester, MA, USA
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38
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Coyne AN, Zaepfel BL, Zarnescu DC. Failure to Deliver and Translate-New Insights into RNA Dysregulation in ALS. Front Cell Neurosci 2017; 11:243. [PMID: 28860970 PMCID: PMC5562674 DOI: 10.3389/fncel.2017.00243] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2017] [Accepted: 07/31/2017] [Indexed: 12/12/2022] Open
Abstract
Amyotrophic Lateral Sclerosis (ALS) is a progressive and fatal neurodegenerative disease affecting both upper and lower motor neurons. The molecular mechanisms underlying disease pathogenesis remain largely unknown. Multiple genetic loci including genes involved in proteostasis and ribostasis have been linked to ALS providing key insights into the molecular mechanisms underlying disease. In particular, the identification of the RNA binding proteins TDP-43 and fused in sarcoma (FUS) as causative factors of ALS resulted in a paradigm shift centered on the study of RNA dysregulation as a major mechanism of disease. With wild-type TDP-43 pathology being found in ~97% of ALS cases and the identification of disease causing mutations within its sequence, TDP-43 has emerged as a prominent player in ALS. More recently, studies of the newly discovered C9orf72 repeat expansion are lending further support to the notion of defects in RNA metabolism as a key factor underlying ALS. RNA binding proteins are involved in all aspects of RNA metabolism ranging from splicing, transcription, transport, storage into RNA/protein granules, and translation. How these processes are affected by disease-associated mutations is just beginning to be understood. Considerable work has gone into the identification of splicing and transcription defects resulting from mutations in RNA binding proteins associated with disease. More recently, defects in RNA transport and translation have been shown to be involved in the pathomechanism of ALS. A central hypothesis in the field is that disease causing mutations lead to the persistence of RNA/protein complexes known as stress granules. Under times of prolonged cellular stress these granules sequester specific mRNAs preventing them from translation, and are thought to evolve into pathological aggregates. Here we will review recent efforts directed at understanding how altered RNA metabolism contributes to ALS pathogenesis.
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Affiliation(s)
- Alyssa N Coyne
- Department of Molecular and Cellular Biology, University of ArizonaTucson, AZ, United States.,Department of Neuroscience, University of ArizonaTucson, AZ, United States
| | - Benjamin L Zaepfel
- Department of Molecular and Cellular Biology, University of ArizonaTucson, AZ, United States
| | - Daniela C Zarnescu
- Department of Molecular and Cellular Biology, University of ArizonaTucson, AZ, United States.,Department of Neuroscience, University of ArizonaTucson, AZ, United States.,Department of Neurology, University of ArizonaTucson, AZ, United States
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