1
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Li CL, Zhou GF, Xie XY, Wang L, Chen X, Pan QL, Pu YL, Yang J, Song L, Chen GJ. STAU1 exhibits a dual function by promoting amyloidogenesis and tau phosphorylation in cultured cells. Exp Neurol 2024; 377:114805. [PMID: 38729552 DOI: 10.1016/j.expneurol.2024.114805] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2023] [Revised: 04/25/2024] [Accepted: 04/30/2024] [Indexed: 05/12/2024]
Abstract
Staufen-1 (STAU1) is a double-stranded RNA-binding protein (RBP) involved in a variety of pathological conditions. In this study, we investigated the potential role of STAU1 in Alzheimer's disease (AD), in which two hallmarks are well-established as cerebral β-amyloid protein (Aβ) deposition and Tau-centered neurofibrillary tangles. We found that STAU1 protein level was significantly increased in cells that stably express full-length APP and the brain of APP/PS1 mice, an animal model of AD. STAU1 knockdown, as opposed to overexpression, significantly decreased the protein levels of β-amyloid converting enzyme 1 (BACE1) and Aβ. We further found that STAU1 extended the half-life of the BACE1 mRNA through binding to the 3' untranslated region (3'UTR). Transcriptome analysis revealed that STAU1 enhanced the expression of growth arrest and DNA damage 45 β (GADD45B) upstream of P38 MAPK signaling, which contributed to STAU1-induced regulation of Tau phosphorylation at Ser396 and Thr181. Together, STAU1 promoted amyloidogenesis by inhibiting BACE1 mRNA decay, and augmented Tau phosphorylation through activating GADD45B in relation to P38 MAPK. Targeting STAU1 that acts on both amyloidogenesis and tauopathy may serve as an optimistic approach for AD treatment.
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Affiliation(s)
- Chen-Lu Li
- Department of Neurology, The First Affiliated Hospital Of Chongqing Medical University, Chongqing Key Laboratory of Major Neurological and Mental Disorders, Chongqing Key Laboratory of Neurology, 1 Youyi Road, Chongqing 400016, China
| | - Gui-Feng Zhou
- Department of Neurology, The First Affiliated Hospital Of Chongqing Medical University, Chongqing Key Laboratory of Major Neurological and Mental Disorders, Chongqing Key Laboratory of Neurology, 1 Youyi Road, Chongqing 400016, China
| | - Xiao-Yong Xie
- Department of Neurology, The First Affiliated Hospital Of Chongqing Medical University, Chongqing Key Laboratory of Major Neurological and Mental Disorders, Chongqing Key Laboratory of Neurology, 1 Youyi Road, Chongqing 400016, China
| | - Lu Wang
- Department of Neurology, The First Affiliated Hospital Of Chongqing Medical University, Chongqing Key Laboratory of Major Neurological and Mental Disorders, Chongqing Key Laboratory of Neurology, 1 Youyi Road, Chongqing 400016, China
| | - Xue Chen
- Department of Neurology, The First Affiliated Hospital Of Chongqing Medical University, Chongqing Key Laboratory of Major Neurological and Mental Disorders, Chongqing Key Laboratory of Neurology, 1 Youyi Road, Chongqing 400016, China
| | - Qiu-Ling Pan
- Department of Neurology, The First Affiliated Hospital Of Chongqing Medical University, Chongqing Key Laboratory of Major Neurological and Mental Disorders, Chongqing Key Laboratory of Neurology, 1 Youyi Road, Chongqing 400016, China
| | - Ya-Lan Pu
- Department of Neurology, The First Affiliated Hospital Of Chongqing Medical University, Chongqing Key Laboratory of Major Neurological and Mental Disorders, Chongqing Key Laboratory of Neurology, 1 Youyi Road, Chongqing 400016, China
| | - Jie Yang
- Department of Neurology, The First Affiliated Hospital Of Chongqing Medical University, Chongqing Key Laboratory of Major Neurological and Mental Disorders, Chongqing Key Laboratory of Neurology, 1 Youyi Road, Chongqing 400016, China
| | - Li Song
- Department of Neurology, The First Affiliated Hospital Of Chongqing Medical University, Chongqing Key Laboratory of Major Neurological and Mental Disorders, Chongqing Key Laboratory of Neurology, 1 Youyi Road, Chongqing 400016, China
| | - Guo-Jun Chen
- Department of Neurology, The First Affiliated Hospital Of Chongqing Medical University, Chongqing Key Laboratory of Major Neurological and Mental Disorders, Chongqing Key Laboratory of Neurology, 1 Youyi Road, Chongqing 400016, China.
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2
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D'Antoni S, Spatuzza M, Bonaccorso CM, Catania MV. Role of fragile X messenger ribonucleoprotein 1 in the pathophysiology of brain disorders: a glia perspective. Neurosci Biobehav Rev 2024; 162:105731. [PMID: 38763180 DOI: 10.1016/j.neubiorev.2024.105731] [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: 02/23/2024] [Revised: 05/14/2024] [Accepted: 05/15/2024] [Indexed: 05/21/2024]
Abstract
Fragile X messenger ribonucleoprotein 1 (FMRP) is a widely expressed RNA binding protein involved in several steps of mRNA metabolism. Mutations in the FMR1 gene encoding FMRP are responsible for fragile X syndrome (FXS), a leading genetic cause of intellectual disability and autism spectrum disorder, and fragile X-associated tremor-ataxia syndrome (FXTAS), a neurodegenerative disorder in aging men. Although FMRP is mainly expressed in neurons, it is also present in glial cells and its deficiency or altered expression can affect functions of glial cells with implications for the pathophysiology of brain disorders. The present review focuses on recent advances on the role of glial subtypes, astrocytes, oligodendrocytes and microglia, in the pathophysiology of FXS and FXTAS, and describes how the absence or reduced expression of FMRP in these cells can impact on glial and neuronal functions. We will also briefly address the role of FMRP in radial glial cells and its effects on neural development, and gliomas and will speculate on the role of glial FMRP in other brain disorders.
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Affiliation(s)
- S D'Antoni
- Institute for Biomedical Research and Innovation (IRIB), National Research Council (CNR), Via Paolo Gaifami 18, Catania 95126, Italy
| | - M Spatuzza
- Institute for Biomedical Research and Innovation (IRIB), National Research Council (CNR), Via Paolo Gaifami 18, Catania 95126, Italy
| | - C M Bonaccorso
- Oasi Research Institute - IRCCS, via Conte Ruggero 73, Troina 94018, Italy
| | - M V Catania
- Institute for Biomedical Research and Innovation (IRIB), National Research Council (CNR), Via Paolo Gaifami 18, Catania 95126, Italy.
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3
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Taha MS, Ahmadian MR. Fragile X Messenger Ribonucleoprotein Protein and Its Multifunctionality: From Cytosol to Nucleolus and Back. Biomolecules 2024; 14:399. [PMID: 38672417 PMCID: PMC11047961 DOI: 10.3390/biom14040399] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2024] [Revised: 03/17/2024] [Accepted: 03/19/2024] [Indexed: 04/28/2024] Open
Abstract
Silencing of the fragile X messenger ribonucleoprotein 1 (FMR1) gene and a consequent lack of FMR protein (FMRP) synthesis are associated with fragile X syndrome, one of the most common inherited intellectual disabilities. FMRP is a multifunctional protein that is involved in many cellular functions in almost all subcellular compartments under both normal and cellular stress conditions in neuronal and non-neuronal cell types. This is achieved through its trafficking signals, nuclear localization signal (NLS), nuclear export signal (NES), and nucleolar localization signal (NoLS), as well as its RNA and protein binding domains, and it is modulated by various post-translational modifications such as phosphorylation, ubiquitination, sumoylation, and methylation. This review summarizes the recent advances in understanding the interaction networks of FMRP with a special focus on FMRP stress-related functions, including stress granule formation, mitochondrion and endoplasmic reticulum plasticity, ribosome biogenesis, cell cycle control, and DNA damage response.
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Affiliation(s)
- Mohamed S. Taha
- Institute of Biochemistry and Molecular Biology II, Medical Faculty, Heinrich Heine University Düsseldorf, 40225 Düsseldorf, Germany;
- Research on Children with Special Needs Department, Institute of Medical Research and Clinical Studies, National Research Centre, Cairo 12622, Egypt
| | - Mohammad Reza Ahmadian
- Institute of Biochemistry and Molecular Biology II, Medical Faculty, Heinrich Heine University Düsseldorf, 40225 Düsseldorf, Germany;
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McKeever PM, Sababi AM, Sharma R, Khuu N, Xu Z, Shen SY, Xiao S, McGoldrick P, Orouji E, Ketela T, Sato C, Moreno D, Visanji N, Kovacs GG, Keith J, Zinman L, Rogaeva E, Goodarzi H, Bader GD, Robertson J. Single-nucleus multiomic atlas of frontal cortex in amyotrophic lateral sclerosis with a deep learning-based decoding of alternative polyadenylation mechanisms. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.12.22.573083. [PMID: 38187588 PMCID: PMC10769403 DOI: 10.1101/2023.12.22.573083] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2024]
Abstract
The understanding of how different cell types contribute to amyotrophic lateral sclerosis (ALS) pathogenesis is limited. Here we generated a single-nucleus transcriptomic and epigenomic atlas of the frontal cortex of ALS cases with C9orf72 (C9) hexanucleotide repeat expansions and sporadic ALS (sALS). Our findings reveal shared pathways in C9-ALS and sALS, characterized by synaptic dysfunction in excitatory neurons and a disease-associated state in microglia. The disease subtypes diverge with loss of astrocyte homeostasis in C9-ALS, and a more substantial disturbance of inhibitory neurons in sALS. Leveraging high depth 3'-end sequencing, we found a widespread switch towards distal polyadenylation (PA) site usage across ALS subtypes relative to controls. To explore this differential alternative PA (APA), we developed APA-Net, a deep neural network model that uses transcript sequence and expression levels of RNA-binding proteins (RBPs) to predict cell-type specific APA usage and RBP interactions likely to regulate APA across disease subtypes.
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5
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García Morato J, Gloeckner CJ, Kahle PJ. Proteomics elucidating physiological and pathological functions of TDP-43. Proteomics 2023; 23:e2200410. [PMID: 37671599 DOI: 10.1002/pmic.202200410] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2023] [Revised: 08/02/2023] [Accepted: 08/10/2023] [Indexed: 09/07/2023]
Abstract
Trans-activation response DNA binding protein of 43 kDa (TDP-43) regulates a great variety of cellular processes in the nucleus and cytosol. In addition, a defined subset of neurodegenerative diseases is characterized by nuclear depletion of TDP-43 as well as cytosolic mislocalization and aggregation. To perform its diverse functions TDP-43 can associate with different ribonucleoprotein complexes. Combined with transcriptomics, MS interactome studies have unveiled associations between TDP-43 and the spliceosome machinery, polysomes and RNA granules. Moreover, the highly dynamic, low-valency interactions regulated by its low-complexity domain calls for innovative proximity labeling methodologies. In addition to protein partners, the analysis of post-translational modifications showed that they may play a role in the nucleocytoplasmic shuttling, RNA binding, liquid-liquid phase separation and protein aggregation of TDP-43. Here we review the various TDP-43 ribonucleoprotein complexes characterized so far, how they contribute to the diverse functions of TDP-43, and roles of post-translational modifications. Further understanding of the fluid dynamic properties of TDP-43 in ribonucleoprotein complexes, RNA granules, and self-assemblies will advance the understanding of RNA processing in cells and perhaps help to develop novel therapeutic approaches for TDPopathies.
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Affiliation(s)
- Jorge García Morato
- Laboratory of Functional Neurogenetics, Department of Neurodegeneration, German Center of Neurodegenerative Diseases and Hertie Institute for Clinical Brain Research, University of Tübingen, Tübingen, Germany
| | - Christian Johannes Gloeckner
- Research Group Functional Neuroproteomics, German Center of Neurodegenerative Diseases, Tübingen, Germany
- Core Facility for Medical Bioanalytics, Institute for Ophthalmic Research, Center for Ophthalmology, University of Tübingen, Tübingen, Germany
| | - Philipp J Kahle
- Laboratory of Functional Neurogenetics, Department of Neurodegeneration, German Center of Neurodegenerative Diseases and Hertie Institute for Clinical Brain Research, University of Tübingen, Tübingen, Germany
- Department of Biochemistry, University of Tübingen, Tübingen, Germany
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6
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Gimenez J, Spalloni A, Cappelli S, Ciaiola F, Orlando V, Buratti E, Longone P. TDP-43 Epigenetic Facets and Their Neurodegenerative Implications. Int J Mol Sci 2023; 24:13807. [PMID: 37762112 PMCID: PMC10530927 DOI: 10.3390/ijms241813807] [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: 07/06/2023] [Revised: 07/31/2023] [Accepted: 08/09/2023] [Indexed: 09/29/2023] Open
Abstract
Since its initial involvement in numerous neurodegenerative pathologies in 2006, either as a principal actor or as a cofactor, new pathologies implicating transactive response (TAR) DNA-binding protein 43 (TDP-43) are regularly emerging also beyond the neuronal system. This reflects the fact that TDP-43 functions are particularly complex and broad in a great variety of human cells. In neurodegenerative diseases, this protein is often pathologically delocalized to the cytoplasm, where it irreversibly aggregates and is subjected to various post-translational modifications such as phosphorylation, polyubiquitination, and cleavage. Until a few years ago, the research emphasis has been focused particularly on the impacts of this aggregation and/or on its widely described role in complex RNA splicing, whether related to loss- or gain-of-function mechanisms. Interestingly, recent studies have strengthened the knowledge of TDP-43 activity at the chromatin level and its implication in the regulation of DNA transcription and stability. These discoveries have highlighted new features regarding its own transcriptional regulation and suggested additional mechanistic and disease models for the effects of TPD-43. In this review, we aim to give a comprehensive view of the potential epigenetic (de)regulations driven by (and driving) this multitask DNA/RNA-binding protein.
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Affiliation(s)
- Juliette Gimenez
- Molecular Neurobiology Laboratory, Experimental Neuroscience, IRCCS Fondazione Santa Lucia (FSL), 00143 Rome, Italy; (A.S.); (P.L.)
| | - Alida Spalloni
- Molecular Neurobiology Laboratory, Experimental Neuroscience, IRCCS Fondazione Santa Lucia (FSL), 00143 Rome, Italy; (A.S.); (P.L.)
| | - Sara Cappelli
- Molecular Pathology Laboratory, International Centre for Genetic Engineering and Biotechnology (ICGEB), 34149 Trieste, Italy; (S.C.); (E.B.)
| | - Francesca Ciaiola
- Molecular Neurobiology Laboratory, Experimental Neuroscience, IRCCS Fondazione Santa Lucia (FSL), 00143 Rome, Italy; (A.S.); (P.L.)
- Department of Systems Medicine, University of Roma Tor Vergata, 00133 Rome, Italy
| | - Valerio Orlando
- KAUST Environmental Epigenetics Program, Biological Environmental Sciences and Engineering Division BESE, King Abdullah University of Science and Technology (KAUST), Thuwal 23955, Saudi Arabia;
| | - Emanuele Buratti
- Molecular Pathology Laboratory, International Centre for Genetic Engineering and Biotechnology (ICGEB), 34149 Trieste, Italy; (S.C.); (E.B.)
| | - Patrizia Longone
- Molecular Neurobiology Laboratory, Experimental Neuroscience, IRCCS Fondazione Santa Lucia (FSL), 00143 Rome, Italy; (A.S.); (P.L.)
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Zhou J, Shi Q, Ge YY, He W, Hu X, Xia W, Yan R. Reticulons 1 and 3 are essential for axonal growth and synaptic maintenance associated with intellectual development. Hum Mol Genet 2023; 32:2587-2599. [PMID: 37228035 PMCID: PMC10407710 DOI: 10.1093/hmg/ddad085] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2023] [Revised: 04/25/2023] [Accepted: 04/29/2023] [Indexed: 05/27/2023] Open
Abstract
Reticulon (RTN) proteins are a family of proteins biochemically identified for shaping tubular endoplasmic reticulum, a subcellular structure important for vesicular transport and cell-to-cell communication. In our recent study of mice with knockout of both reticulon 1 (Rtn1) and Rtn3, we discovered that Rtn1-/-;Rtn3-/- (brief as R1R3dKO) mice exhibited neonatal lethality, despite the fact that mice deficient in either RTN1 or RTN3 alone exhibit no discernible phenotypes. This has been the first case to find early lethality in animals with deletion of partial members of RTN proteins. The complete penetrance for neonatal lethality can be attributed to multiple defects including the impaired neuromuscular junction found in the diaphragm. We also observed significantly impaired axonal growth in a regional-specific manner, detected by immunohistochemical staining with antibodies to neurofilament light chain and neurofilament medium chain. Ultrastructural examination by electron microscopy revealed a significant reduction in synaptic active zone length in the hippocampus. Mechanistic exploration by unbiased proteomic assays revealed reduction of proteins such as FMR1, Staufen2, Cyfip1, Cullin-4B and PDE2a, which are known components in the fragile X mental retardation pathway. Together, our results reveal that RTN1 and RTN3 are required to orchestrate neurofilament organization and intact synaptic structure of the central nervous system.
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Affiliation(s)
- John Zhou
- Department of Neuroscience, UConn Health, 263 Farmington Avenue, Farmington, CT 06030-3401, USA
- Department of Neuroscience, Cleveland Clinic Lerner Research Institute, 9500 Euclid Avenue, Cleveland, OH 44195, USA
| | - Qi Shi
- Department of Neuroscience, Cleveland Clinic Lerner Research Institute, 9500 Euclid Avenue, Cleveland, OH 44195, USA
| | - Ying Y Ge
- Department of Neuroscience, UConn Health, 263 Farmington Avenue, Farmington, CT 06030-3401, USA
- Department of Neuroscience, Cleveland Clinic Lerner Research Institute, 9500 Euclid Avenue, Cleveland, OH 44195, USA
| | - Wanxia He
- Department of Neuroscience, UConn Health, 263 Farmington Avenue, Farmington, CT 06030-3401, USA
- Department of Neuroscience, Cleveland Clinic Lerner Research Institute, 9500 Euclid Avenue, Cleveland, OH 44195, USA
| | - Xiangyou Hu
- Department of Neuroscience, UConn Health, 263 Farmington Avenue, Farmington, CT 06030-3401, USA
- Department of Neuroscience, Cleveland Clinic Lerner Research Institute, 9500 Euclid Avenue, Cleveland, OH 44195, USA
| | - Weiming Xia
- Pharmacology & Experimental Therapeutics, Boston University, 72 E Concord St, Boston, MA 02118, USA
- Geriatric Research Education and Clinical Center, Bedford VA Healthcare System, Bedford, MA 01730, USA
- Biological Sciences, Kennedy College of Science, University of Massachusetts Lowell, Lowell, MA 01854, USA
| | - Riqiang Yan
- Department of Neuroscience, UConn Health, 263 Farmington Avenue, Farmington, CT 06030-3401, USA
- Department of Neuroscience, Cleveland Clinic Lerner Research Institute, 9500 Euclid Avenue, Cleveland, OH 44195, USA
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8
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Ionescu A, Altman T, Perlson E. Looking for answers far away from the soma-the (un)known axonal functions of TDP-43, and their contribution to early NMJ disruption in ALS. Mol Neurodegener 2023; 18:35. [PMID: 37259156 DOI: 10.1186/s13024-023-00623-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2022] [Accepted: 05/01/2023] [Indexed: 06/02/2023] Open
Abstract
Axon degeneration and Neuromuscular Junction (NMJ) disruption are key pathologies in the fatal neurodegenerative disease Amyotrophic Lateral Sclerosis (ALS). Despite accumulating evidence that axons and NMJs are impacted at a very early stage of the disease, current knowledge about the mechanisms leading to their degeneration remains elusive. Cytoplasmic mislocalization and accumulation of the protein TDP-43 are considered key pathological hallmarks of ALS, as they occur in ~ 97% of ALS patients, both sporadic and familial. Recent studies have identified pathological accumulation of TDP-43 in intramuscular nerves of muscle biopsies collected from pre-diagnosed, early symptomatic ALS patients. These findings suggest a gain of function for TDP-43 in axons, which might facilitate early NMJ disruption. In this review, we dissect the process leading to axonal TDP-43 accumulation and phosphorylation, discuss the known and hypothesized roles TDP-43 plays in healthy axons, and review possible mechanisms that connect TDP-43 pathology to the axon and NMJ degeneration in ALS.
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Affiliation(s)
- Ariel Ionescu
- Department of Physiology and Pharmacology, Sackler Faculty of Medicine, Tel Aviv University, Room 605, Ramat Aviv, 69978, Tel Aviv, Israel
| | - Topaz Altman
- Department of Physiology and Pharmacology, Sackler Faculty of Medicine, Tel Aviv University, Room 605, Ramat Aviv, 69978, Tel Aviv, Israel
| | - Eran Perlson
- Department of Physiology and Pharmacology, Sackler Faculty of Medicine, Tel Aviv University, Room 605, Ramat Aviv, 69978, Tel Aviv, Israel.
- Sagol School of Neuroscience, Tel-Aviv University, Tel-Aviv, Israel.
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9
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Mueller S, Decker L, Menge S, Ludolph AC, Freischmidt A. The Fragile X Protein Family in Amyotrophic Lateral Sclerosis. Mol Neurobiol 2023; 60:3898-3910. [PMID: 36991279 DOI: 10.1007/s12035-023-03330-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2022] [Accepted: 03/23/2023] [Indexed: 03/31/2023]
Abstract
The fragile X protein (FXP) family comprises the multifunctional RNA-binding proteins FMR1, FXR1, and FXR2 that play an important role in RNA metabolism and regulation of translation, but also in DNA damage and cellular stress responses, mitochondrial organization, and more. FMR1 is well known for its implication in neurodevelopmental diseases. Recent evidence suggests substantial contribution of this protein family to amyotrophic lateral sclerosis (ALS) pathogenesis. ALS is a highly heterogeneous neurodegenerative disease with multiple genetic and unclear environmental causes and very limited treatment options. The loss of motoneurons in ALS is still poorly understood, especially because pathogenic mechanisms are often restricted to patients with mutations in specific causative genes. Identification of converging disease mechanisms evident in most patients and suitable for therapeutic intervention is therefore of high importance. Recently, deregulation of the FXPs has been linked to pathogenic processes in different types of ALS. Strikingly, in many cases, available data points towards loss of expression and/or function of the FXPs early in the disease, or even at the presymptomatic state. In this review, we briefly introduce the FXPs and summarize available data about these proteins in ALS. This includes their relation to TDP-43, FUS, and ALS-related miRNAs, as well as their possible contribution to pathogenic protein aggregation and defective RNA editing. Furthermore, open questions that need to be addressed before definitively judging suitability of these proteins as novel therapeutic targets are discussed.
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Affiliation(s)
- Sarah Mueller
- Department of Neurology, Ulm University, Albert-Einstein-Allee 11, 89081, Ulm, Germany
| | - Lorena Decker
- Department of Neurology, Ulm University, Albert-Einstein-Allee 11, 89081, Ulm, Germany
| | - Sonja Menge
- Department of Neurology, Ulm University, Albert-Einstein-Allee 11, 89081, Ulm, Germany
| | - Albert C Ludolph
- Department of Neurology, Ulm University, Albert-Einstein-Allee 11, 89081, Ulm, Germany
- German Center For Neurodegenerative Diseases (DZNE) Ulm, Ulm, Germany
| | - Axel Freischmidt
- Department of Neurology, Ulm University, Albert-Einstein-Allee 11, 89081, Ulm, Germany.
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Sustained therapeutic benefits by transient reduction of TDP-43 using ENA-modified antisense oligonucleotides in ALS/FTD mice. MOLECULAR THERAPY. NUCLEIC ACIDS 2023; 31:353-366. [PMID: 36817728 PMCID: PMC9925842 DOI: 10.1016/j.omtn.2023.01.006] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/22/2022] [Accepted: 01/12/2023] [Indexed: 01/17/2023]
Abstract
The abnormal aggregation of TDP-43 into cytoplasmic inclusions in affected neurons is a pathological hallmark of amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD). Although how TDP-43 forms cytoplasmic aggregates and causes neurodegeneration in patients with ALS/FTD remains unclear, reducing cellular TDP-43 levels is likely to prevent aggregation and to rescue neurons from TDP-43 toxicity. To address this issue, here we developed gapmer-type antisense oligonucleotides (ASOs) against human TDP-43 using 2'-O,4'-C-ethylene nucleic acids (ENAs), which are modified nucleic acids with high stability, and tested the therapeutic potential of lowering TDP-43 levels using ENA-modified ASOs. We demonstrated that intracerebroventricular administration of ENA-modified ASOs into a mouse model of ALS/FTD expressing human TDP-43 results in the efficient reduction of TDP-43 levels in the brain and spinal cord. Surprisingly, a single injection of ENA-modified ASOs into TDP-43 mice led to long-lasting improvement of behavioral abnormalities and the suppression of cytoplasmic TDP-43 aggregation, even after TDP-43 levels had returned to the initial levels. Our results demonstrate that transient reduction of TDP-43 using ENA-modified ASOs leads to sustained therapeutic benefits in vivo, indicating the possibility of a disease-modifying therapy by lowering TDP-43 levels for the treatment of the TDP-43 proteinopathies, including ALS/FTD.
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11
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Ziętara P, Dziewięcka M, Augustyniak M. Why Is Longevity Still a Scientific Mystery? Sirtuins-Past, Present and Future. Int J Mol Sci 2022; 24:ijms24010728. [PMID: 36614171 PMCID: PMC9821238 DOI: 10.3390/ijms24010728] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2022] [Revised: 12/22/2022] [Accepted: 12/27/2022] [Indexed: 01/03/2023] Open
Abstract
The sirtuin system consists of seven highly conserved regulatory enzymes responsible for metabolism, antioxidant protection, and cell cycle regulation. The great interest in sirtuins is associated with the potential impact on life extension. This article summarizes the latest research on the activity of sirtuins and their role in the aging process. The effects of compounds that modulate the activity of sirtuins were discussed, and in numerous studies, their effectiveness was demonstrated. Attention was paid to the role of a caloric restriction and the risks associated with the influence of careless sirtuin modulation on the organism. It has been shown that low modulators' bioavailability/retention time is a crucial problem for optimal regulation of the studied pathways. Therefore, a detailed understanding of the modulator structure and potential reactivity with sirtuins in silico studies should precede in vitro and in vivo experiments. The latest achievements in nanobiotechnology make it possible to create promising molecules, but many of them remain in the sphere of plans and concepts. It seems that solving the mystery of longevity will have to wait for new scientific discoveries.
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12
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Klusek J, Newman-Norlund R, Fairchild AJ, Newman-Norlund S, Sayers S, Stewart JC, Berry-Kravis E, Fridriksson J. Low normal FMR1 genotype in older adult women: Psychological well-being and motor function. Arch Gerontol Geriatr 2022; 103:104789. [PMID: 35981426 PMCID: PMC9464716 DOI: 10.1016/j.archger.2022.104789] [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: 04/06/2022] [Revised: 08/01/2022] [Accepted: 08/09/2022] [Indexed: 11/28/2022]
Abstract
The FMR1 gene plays a key role in adult neurogenesis and neuroplasticity, and thus may contribute to age-related health in the population. The current study focused on the "low normal" FMR1 genotype, defined by lower-than-typical numbers of FMR1 CGG repeats (<26), as a potential genetic determinant of age-related health. We characterized the effect of the low normal FMR1 genotype on psychological well-being and motor function in a racially diverse non-clinical sample of older adult women. Women with low CGG repeats were distinguished from those with CGGs falling within the mid-high end of the normal range by reduced performance on multimodal assessments of motor function and psychological well-being, with large effect sizes. Robust continuous associations were also detected between lower CGG repeat length and reduced psychological well-being, balance, and dexterity. Findings suggest that FMR1 may represent an important mediator of individual differences in age-related health; larger epidemiological studies are needed. Given that approximately 23-35% of females carry the low normal genotype, efforts to understand its clinical effects have relevance a broad swath of the aging population.
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Affiliation(s)
- Jessica Klusek
- Department of Communication Sciences and Disorders, Arnold School of Public Health, University of South Carolina, Close-Hipp Building, 1705 College Street, Columbia, SC 29208, USA.
| | - Roger Newman-Norlund
- Department of Communication Sciences and Disorders, Arnold School of Public Health, University of South Carolina, Close-Hipp Building, 1705 College Street, Columbia, SC 29208, USA; Department of Psychology, University of South Carolina, 1512 Pendleton Street, Columbia, SC 29208, USA
| | - Amanda J Fairchild
- Department of Psychology, University of South Carolina, 1512 Pendleton Street, Columbia, SC 29208, USA
| | - Sarah Newman-Norlund
- Department of Communication Sciences and Disorders, Arnold School of Public Health, University of South Carolina, Close-Hipp Building, 1705 College Street, Columbia, SC 29208, USA
| | - Sara Sayers
- Department of Communication Sciences and Disorders, Arnold School of Public Health, University of South Carolina, Close-Hipp Building, 1705 College Street, Columbia, SC 29208, USA
| | - Jill C Stewart
- Physical Therapy Program, Department of Exercise Science, Arnold School of Public Health, University of South Carolina, 921 Assembly Street, Columbia, SC 29208, USA
| | - Elizabeth Berry-Kravis
- Department of Pediatrics, Neurological Sciences and Anatomy and Cell Biology, Rush University Medical Center, 1725 West Harrison Street, Suite 718, Chicago, IL 60612, USA
| | - Julius Fridriksson
- Department of Communication Sciences and Disorders, Arnold School of Public Health, University of South Carolina, Close-Hipp Building, 1705 College Street, Columbia, SC 29208, USA
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13
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Wei XF, Fan SY, Wang YW, Li S, Long SY, Gan CY, Li J, Sun YX, Guo L, Wang PY, Yang X, Wang JL, Cui J, Zhang WL, Huang AL, Hu JL. Identification of STAU1 as a regulator of HBV replication by TurboID-based proximity labeling. iScience 2022; 25:104416. [PMID: 35663023 PMCID: PMC9156947 DOI: 10.1016/j.isci.2022.104416] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2021] [Revised: 04/21/2022] [Accepted: 05/12/2022] [Indexed: 11/17/2022] Open
Abstract
The core promoter (CP) of hepatitis B virus (HBV) is critical for HBV replication by controlling the transcription of pregenomic RNA (pgRNA). Host factors regulating the activity of the CP can be identified by different methods. Biotin-based proximity labeling, a powerful method with the capability to capture weak or dynamic interactions, has not yet been used to map proteins interacting with the CP. Here, we established a strategy, based on the newly evolved promiscuous enzyme TurboID, for interrogating host factors regulating the activity of HBV CP. Using this strategy, we identified STAU1 as an important factor involved in the regulation of HBV CP. Mechanistically, STAU1 indirectly binds to CP mediated by TARDBP, and recruits the SAGA transcription coactivator complex to the CP to upregulate its activity. Moreover, STAU1 binds to HBx and enhances the level of HBx by stabilizing it in a ubiquitin-independent manner. HBV core promoter binding factors were interrogated by a proximity labeling method STAU1 enhances HBV transcription and replication STAU1 indirectly binds to core promoter via TARDBP and recruits SAGA complex STAU1 binds to HBx and increases its stability
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Affiliation(s)
- Xia-Fei Wei
- Key Laboratory of Molecular Biology on Infectious Diseases, Ministry of Education, Chongqing Medical University, Chongqing, China.,Institute for Hepatology, National Clinical Research Center for Infectious Disease, Shenzhen Third People's Hospital, Southern University of Science and Technology, Shenzhen, China
| | - Shu-Ying Fan
- Key Laboratory of Molecular Biology on Infectious Diseases, Ministry of Education, Chongqing Medical University, Chongqing, China
| | - Yu-Wei Wang
- Department of Laboratory Medicine, Chongqing Hospital of Traditional Chinese Medicine, Chongqing, China
| | - Shan Li
- Key Laboratory of Molecular Biology on Infectious Diseases, Ministry of Education, Chongqing Medical University, Chongqing, China
| | - Shao-Yuan Long
- Key Laboratory of Molecular Biology on Infectious Diseases, Ministry of Education, Chongqing Medical University, Chongqing, China
| | - Chun-Yang Gan
- Key Laboratory of Molecular Biology on Infectious Diseases, Ministry of Education, Chongqing Medical University, Chongqing, China
| | - Jie Li
- Key Laboratory of Molecular Biology on Infectious Diseases, Ministry of Education, Chongqing Medical University, Chongqing, China
| | - Yu-Xue Sun
- Key Laboratory of Molecular Biology on Infectious Diseases, Ministry of Education, Chongqing Medical University, Chongqing, China
| | - Lin Guo
- Key Laboratory of Molecular Biology on Infectious Diseases, Ministry of Education, Chongqing Medical University, Chongqing, China
| | - Pei-Yun Wang
- Key Laboratory of Molecular Biology on Infectious Diseases, Ministry of Education, Chongqing Medical University, Chongqing, China
| | - Xue Yang
- Key Laboratory of Molecular Biology on Infectious Diseases, Ministry of Education, Chongqing Medical University, Chongqing, China
| | - Jin-Lan Wang
- Key Laboratory of Molecular Biology on Infectious Diseases, Ministry of Education, Chongqing Medical University, Chongqing, China
| | - Jing Cui
- Key Laboratory of Molecular Biology on Infectious Diseases, Ministry of Education, Chongqing Medical University, Chongqing, China
| | - Wen-Lu Zhang
- Key Laboratory of Molecular Biology on Infectious Diseases, Ministry of Education, Chongqing Medical University, Chongqing, China
| | - Ai-Long Huang
- Key Laboratory of Molecular Biology on Infectious Diseases, Ministry of Education, Chongqing Medical University, Chongqing, China
| | - Jie-Li Hu
- Key Laboratory of Molecular Biology on Infectious Diseases, Ministry of Education, Chongqing Medical University, Chongqing, China
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14
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Song C, Leahy SN, Rushton EM, Broadie K. RNA-binding FMRP and Staufen sequentially regulate the Coracle scaffold to control synaptic glutamate receptor and bouton development. Development 2022; 149:274991. [PMID: 35394012 PMCID: PMC9148565 DOI: 10.1242/dev.200045] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2021] [Accepted: 03/23/2022] [Indexed: 12/16/2022]
Abstract
Both mRNA-binding Fragile X mental retardation protein (FMRP; Fmr1) and mRNA-binding Staufen regulate synaptic bouton formation and glutamate receptor (GluR) levels at the Drosophila neuromuscular junction (NMJ) glutamatergic synapse. Here, we tested whether these RNA-binding proteins act jointly in a common mechanism. We found that both dfmr1 and staufen mutants, and trans-heterozygous double mutants, displayed increased synaptic bouton formation and GluRIIA accumulation. With cell-targeted RNA interference, we showed a downstream Staufen role within postsynaptic muscle. With immunoprecipitation, we showed that FMRP binds staufen mRNA to stabilize postsynaptic transcripts. Staufen is known to target actin-binding, GluRIIA anchor Coracle, and we confirmed that Staufen binds to coracle mRNA. We found that FMRP and Staufen act sequentially to co-regulate postsynaptic Coracle expression, and showed that Coracle, in turn, controls GluRIIA levels and synaptic bouton development. Consistently, we found that dfmr1, staufen and coracle mutants elevate neurotransmission strength. We also identified that FMRP, Staufen and Coracle all suppress pMad activation, providing a trans-synaptic signaling linkage between postsynaptic GluRIIA levels and presynaptic bouton development. This work supports an FMRP-Staufen-Coracle-GluRIIA-pMad pathway regulating structural and functional synapse development.
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Affiliation(s)
- Chunzhu Song
- Department of Biological Sciences, Vanderbilt University and Medical Center, Nashville, TN 37235, USA
| | - Shannon N. Leahy
- Department of Biological Sciences, Vanderbilt University and Medical Center, Nashville, TN 37235, USA
| | - Emma M. Rushton
- Department of Biological Sciences, Vanderbilt University and Medical Center, Nashville, TN 37235, USA
| | - Kendal Broadie
- Department of Biological Sciences, Vanderbilt University and Medical Center, Nashville, TN 37235, USA,Kennedy Center for Research on Human Development, Vanderbilt University and Medical Center, Nashville, TN 37235, USA,Vanderbilt Brain Institute, Vanderbilt University and Medical Center, Nashville, TN 37235, USA,Author for correspondence ()
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15
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Sirtuin-1 sensitive lysine-136 acetylation drives phase separation and pathological aggregation of TDP-43. Nat Commun 2022; 13:1223. [PMID: 35264561 PMCID: PMC8907366 DOI: 10.1038/s41467-022-28822-7] [Citation(s) in RCA: 27] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2020] [Accepted: 01/11/2022] [Indexed: 12/12/2022] Open
Abstract
Trans-activation response DNA-binding protein of 43 kDa (TDP-43) regulates RNA processing and forms neuropathological aggregates in patients with amyotrophic lateral sclerosis and frontotemporal lobar degeneration. Investigating TDP-43 post-translational modifications, we discovered that K84 acetylation reduced nuclear import whereas K136 acetylation impaired RNA binding and splicing capabilities of TDP-43. Such failure of RNA interaction triggered TDP-43 phase separation mediated by the C-terminal low complexity domain, leading to the formation of insoluble aggregates with pathologically phosphorylated and ubiquitinated TDP-43. Introduction of acetyl-lysine at the identified sites via amber suppression confirmed the results from site-directed mutagenesis. K84-acetylated TDP-43 showed cytoplasmic mislocalization, and the aggregation propensity of K136-acetylated TDP-43 was confirmed. We generated antibodies selective for TDP-43 acetylated at these lysines, and found that sirtuin-1 can potently deacetylate K136-acetylated TDP-43 and reduce its aggregation propensity. Thus, distinct lysine acetylations modulate nuclear import, RNA binding and phase separation of TDP-43, suggesting regulatory mechanisms for TDP-43 pathogenesis.
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16
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Bjork RT, Mortimore NP, Loganathan S, Zarnescu DC. Dysregulation of Translation in TDP-43 Proteinopathies: Deficits in the RNA Supply Chain and Local Protein Production. Front Neurosci 2022; 16:840357. [PMID: 35321094 PMCID: PMC8935057 DOI: 10.3389/fnins.2022.840357] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2021] [Accepted: 02/09/2022] [Indexed: 12/19/2022] Open
Abstract
Local control of gene expression provides critical mechanisms for regulating development, maintenance and plasticity in the nervous system. Among the strategies known to govern gene expression locally, mRNA transport and translation have emerged as essential for a neuron’s ability to navigate developmental cues, and to establish, strengthen and remove synaptic connections throughout lifespan. Substantiating the role of RNA processing in the nervous system, several RNA binding proteins have been implicated in both developmental and age dependent neurodegenerative disorders. Of these, TDP-43 is an RNA binding protein that has emerged as a common denominator in amyotrophic lateral sclerosis (ALS), frontotemporal dementia (FTD) and related disorders due to the identification of causative mutations altering its function and its accumulation in cytoplasmic aggregates observed in a significant fraction of ALS/FTD cases, regardless of etiology. TDP-43 is involved in multiple aspects of RNA processing including splicing, transport and translation. Given that one of the early events in disease pathogenesis is mislocalization from the nucleus to the cytoplasm, several studies have focused on elucidating the pathogenic role of TDP-43 in cytoplasmic translation. Here we review recent findings describing TDP-43 translational targets and potential mechanisms of translation dysregulation in TDP-43 proteinopathies across multiple experimental models including cultured cells, flies, mice and patient derived neurons.
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Affiliation(s)
- Reed T. Bjork
- Department of Molecular and Cellular Biology, University of Arizona, Tucson, AZ, United States
- Neuroscience Graduate Interdisciplinary Program, University of Arizona, Tucson, AZ, United States
| | - Nicholas P. Mortimore
- Department of Molecular and Cellular Biology, University of Arizona, Tucson, AZ, United States
| | | | - Daniela C. Zarnescu
- Department of Molecular and Cellular Biology, University of Arizona, Tucson, AZ, United States
- *Correspondence: Daniela C. Zarnescu,
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17
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Bleuzé L, Triaca V, Borreca A. FMRP-Driven Neuropathology in Autistic Spectrum Disorder and Alzheimer's disease: A Losing Game. Front Mol Biosci 2021; 8:699613. [PMID: 34760921 PMCID: PMC8573832 DOI: 10.3389/fmolb.2021.699613] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2021] [Accepted: 08/24/2021] [Indexed: 12/28/2022] Open
Abstract
Fragile X mental retardation protein (FMRP) is an RNA binding protein (RBP) whose absence is essentially associated to Fragile X Syndrome (FXS). As an RNA Binding Protein (RBP), FMRP is able to bind and recognize different RNA structures and the control of specific mRNAs is important for neuronal synaptic plasticity. Perturbations of this pathway have been associated with the autistic spectrum. One of the FMRP partners is the APP mRNA, the main protagonist of Alzheimer’s disease (AD), thereby regulating its protein level and metabolism. Therefore FMRP is associated to two neurodevelopmental and age-related degenerative conditions, respectively FXS and AD. Although these pathologies are characterized by different features, they have been reported to share a number of common molecular and cellular players. The aim of this review is to describe the double-edged sword of FMRP in autism and AD, possibly allowing the elucidation of key shared underlying mechanisms and neuronal circuits. As an RBP, FMRP is able to regulate APP expression promoting the production of amyloid β fragments. Indeed, FXS patients show an increase of amyloid β load, typical of other neurological disorders, such as AD, Down syndrome, Parkinson’s Disease, etc. Beyond APP dysmetabolism, the two neurodegenerative conditions share molecular targets, brain circuits and related cognitive deficits. In this review, we will point out the potential common neuropathological pattern which needs to be addressed and we will hopefully contribute to clarifying the complex phenotype of these two neurorological disorders, in order to pave the way for a novel, common disease-modifying therapy.
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Affiliation(s)
- Louis Bleuzé
- University de Rennes 1, Rennes, France.,Humanitas Clinical and Research Center-IRCCS, Rozzano (Mi), Italy
| | - Viviana Triaca
- Institute of Biochemistry and Cell Biology, National Research Council (CNR-IBBC), International Campus A. Buzzati Traverso, Monterotondo, Italy
| | - Antonella Borreca
- Humanitas Clinical and Research Center-IRCCS, Rozzano (Mi), Italy.,Institute of Neuroscience-National Research Council (CNR-IN), Milan, Italy
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18
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Almasi S, Jasmin BJ. The multifunctional RNA-binding protein Staufen1: an emerging regulator of oncogenesis through its various roles in key cellular events. Cell Mol Life Sci 2021; 78:7145-7160. [PMID: 34633481 PMCID: PMC8629789 DOI: 10.1007/s00018-021-03965-w] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2021] [Revised: 09/19/2021] [Accepted: 09/29/2021] [Indexed: 12/19/2022]
Abstract
The double-stranded multifunctional RNA-binding protein (dsRBP) Staufen was initially discovered in insects as a regulator of mRNA localization. Later, its mammalian orthologs have been described in different organisms, including humans. Two human orthologues of Staufen, named Staufen1 (STAU1) and Staufen2 (STAU2), share some structural and functional similarities. However, given their different spatio-temporal expression patterns, each of these orthologues plays distinct roles in cells. In the current review, we focus on the role of STAU1 in cell functions and cancer development. Since its discovery, STAU1 has mostly been studied for its involvement in various aspects of RNA metabolism. Given the pivotal role of RNA metabolism within cells, recent studies have explored the mechanistic impact of STAU1 in a wide variety of cell functions ranging from cell growth to cell death, as well as in various disease states. In particular, there has been increasing attention on the role of STAU1 in neuromuscular disorders, neurodegeneration, and cancer. Here, we provide an overview of the current knowledge on the role of STAU1 in RNA metabolism and cell functions. We also highlight the link between STAU1-mediated control of cellular functions and cancer development, progression, and treatment. Hence, our review emphasizes the potential of STAU1 as a novel biomarker and therapeutic target for cancer diagnosis and treatment, respectively.
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Affiliation(s)
- Shekoufeh Almasi
- grid.28046.380000 0001 2182 2255Department of Cellular and Molecular Medicine, Faculty of Medicine, University of Ottawa, Ottawa, ON K1H 8M5 Canada
| | - Bernard J. Jasmin
- grid.28046.380000 0001 2182 2255Department of Cellular and Molecular Medicine, Faculty of Medicine, University of Ottawa, Ottawa, ON K1H 8M5 Canada ,grid.28046.380000 0001 2182 2255The Eric J. Poulin Centre for Neuromuscular Diseases, Faculty of Medicine, University of Ottawa, Ottawa, K1H 8M5 Canada
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19
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Pohl F, Goua M, Yates K, Bermano G, Russell WR, Maciel P, Kong Thoo Lin P. Impact of rapeseed pomace extract on markers of oxidative stress and DNA damage in human SH-SY5Y cells. J Food Biochem 2020; 45:e13592. [PMID: 33349958 DOI: 10.1111/jfbc.13592] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2020] [Revised: 11/26/2020] [Accepted: 12/02/2020] [Indexed: 01/05/2023]
Abstract
With increased longevity and subsequent rise in people with age-related neurodegenerative diseases, protection of neurons from oxidative stress damage has become an important field of study. For the first time, we highlight the neuroprotective properties of rapeseed pomace (RSP) extract in SH-SY5Y human neuroblastoma cells. We used resazurin to determine cell metabolism, 2,7'-dichlorofluorescin diacetate (H2 DCFDA) to assess the potential of RSP extracts to shield cells from reactive oxygen species (ROS) induced by H2 O2 using flow cytometry, HPLC to analyze for malondialdehyde (MDA) as a lipid peroxidation marker and the COMET assay to assess DNA strand breakage. Protein stress arrays were used to investigate the cellular pathways affected by RSP extract. No effect on cell metabolism in SH-SY5Y cells was observed after RSP extract treatment (up to 1.5 mg/ml). Pretreatment (24 hr) with RSP extract (1 mg/ml), before H2 O2 -induced stress, alleviated ROS production and DNA strand breakage by 68%, and 38%, respectively. At protein level, the RSP extract increased the levels of FABP-1, HIF-1α, SOD2, and Cytochrome c proteins. Under H2 O2 -induced stress, however, it helped to downregulate p38α levels, a protein kinase which is receptive to stress impulse (mitogen-activated). RSP extract shows very promising cell protective properties in relation to oxidative stress. PRACTICAL APPLICATIONS: Oxidative stress has been associated with numerous diseases for example cancer, diabetes, and many neurological disorders including Parkinson's and Alzheimer's diseases. Hence, there is acceptance among the scientific community of antioxidant therapy and the quest for effective, low cost and readily available sources of natural antioxidants is paramount. Rapeseed plantations are abundant around the world due to the use of rapeseed oil in cooking and as a biofuel. The resulting rapeseed pomace (by-product), specifically its extract, contains high levels of phytochemicals that protect cells against oxidative stress. Therefore, RSP extract can potentially be used/developed as functional food and nutraceuticals in the prevention of many complex neurodegenerative diseases.
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Affiliation(s)
- Franziska Pohl
- School of Pharmacy and Life Sciences, Robert Gordon University, Aberdeen, UK
| | - Marie Goua
- School of Pharmacy and Life Sciences, Robert Gordon University, Aberdeen, UK
| | - Kyari Yates
- School of Pharmacy and Life Sciences, Robert Gordon University, Aberdeen, UK
| | - Giovanna Bermano
- School of Pharmacy and Life Sciences, Robert Gordon University, Aberdeen, UK
| | - Wendy R Russell
- Rowett Institute of Nutrition and Health, University of Aberdeen, Aberdeen, UK
| | - Patrícia Maciel
- Life and Health Sciences Research Institute (ICVS), School of Medicine, University of Minho, Braga, Portugal.,ICVS/3B's-PT Government Associate Laboratory, Braga, Portugal
| | - Paul Kong Thoo Lin
- School of Pharmacy and Life Sciences, Robert Gordon University, Aberdeen, UK
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20
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Wood M, Quinet A, Lin YL, Davis AA, Pasero P, Ayala YM, Vindigni A. TDP-43 dysfunction results in R-loop accumulation and DNA replication defects. J Cell Sci 2020; 133:jcs244129. [PMID: 32989039 PMCID: PMC7648616 DOI: 10.1242/jcs.244129] [Citation(s) in RCA: 33] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2020] [Accepted: 09/17/2020] [Indexed: 12/14/2022] Open
Abstract
TAR DNA-binding protein 43 (TDP-43; also known as TARDBP) is an RNA-binding protein whose aggregation is a hallmark of the neurodegenerative disorders amyotrophic lateral sclerosis and frontotemporal dementia. TDP-43 loss increases DNA damage and compromises cell viability, but the actual function of TDP-43 in preventing genome instability remains unclear. Here, we show that loss of TDP-43 increases R-loop formation in a transcription-dependent manner and results in DNA replication stress. TDP-43 nucleic-acid-binding and self-assembly activities are important in inhibiting R-loop accumulation and preserving normal DNA replication. We also found that TDP-43 cytoplasmic aggregation impairs TDP-43 function in R-loop regulation. Furthermore, increased R-loop accumulation and DNA damage is observed in neurons upon loss of TDP-43. Together, our findings indicate that TDP-43 function and normal protein homeostasis are crucial in maintaining genomic stability through a co-transcriptional process that prevents aberrant R-loop accumulation. We propose that the increased R-loop formation and genomic instability associated with TDP-43 loss are linked to the pathogenesis of TDP-43 proteinopathies.This article has an associated First Person interview with the first author of the paper.
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Affiliation(s)
- Matthew Wood
- Division of Oncology, Department of Medicine, Washington University in St. Louis, St. Louis, MO 63110, USA
- Edward A. Doisy Department of Biochemistry and Molecular Biology, Saint Louis University School of Medicine, St. Louis, MO 63104, USA
| | - Annabel Quinet
- Division of Oncology, Department of Medicine, Washington University in St. Louis, St. Louis, MO 63110, USA
| | - Yea-Lih Lin
- Institut de Génétique Humaine, CNRS et Université de Montpellier, Equipe labélisée Ligue contre le Cancer, Montpellier 34396, France
| | - Albert A Davis
- Department of Neurology, Washington University in St. Louis, St. Louis, MO 63110, USA
| | - Philippe Pasero
- Institut de Génétique Humaine, CNRS et Université de Montpellier, Equipe labélisée Ligue contre le Cancer, Montpellier 34396, France
| | - Yuna M Ayala
- Edward A. Doisy Department of Biochemistry and Molecular Biology, Saint Louis University School of Medicine, St. Louis, MO 63104, USA
| | - Alessandro Vindigni
- Division of Oncology, Department of Medicine, Washington University in St. Louis, St. Louis, MO 63110, USA
- Edward A. Doisy Department of Biochemistry and Molecular Biology, Saint Louis University School of Medicine, St. Louis, MO 63104, USA
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21
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Chu JF, Majumder P, Chatterjee B, Huang SL, Shen CKJ. TDP-43 Regulates Coupled Dendritic mRNA Transport-Translation Processes in Co-operation with FMRP and Staufen1. Cell Rep 2020; 29:3118-3133.e6. [PMID: 31801077 DOI: 10.1016/j.celrep.2019.10.061] [Citation(s) in RCA: 52] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2018] [Revised: 07/12/2019] [Accepted: 10/14/2019] [Indexed: 01/24/2023] Open
Abstract
Tightly regulated transport of messenger ribonucleoprotein (mRNP) granules to diverse locations of dendrites and axons is essential for appropriately timed protein synthesis within distinct sub-neuronal compartments. Perturbations of this regulation lead to various neurological disorders. Using imaging and molecular approaches, we demonstrate how TDP-43 co-operates with two other RNA-binding proteins, FMRP and Staufen1, to regulate the anterograde and retrograde transport, respectively, of Rac1 mRNPs in mouse neuronal dendrites. We also analyze the mechanisms by which TDP-43 mediates coupled mRNA transport-translation processes in dendritic sub-compartments by following in real-time the co-movement of RNA and endogenous fluorescence-tagged protein in neurons and by simultaneous examination of transport/translation dynamics by using an RNA biosensor. This study establishes the pivotal roles of TDP-43 in transporting mRNP granules in dendrites, inhibiting translation inside those granules, and reactivating it once the granules reach the dendritic spines.
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Affiliation(s)
- Jen-Fei Chu
- Institute of Molecular Biology, Academia Sinica, Taipei 115, Taiwan
| | - Pritha Majumder
- Institute of Molecular Biology, Academia Sinica, Taipei 115, Taiwan.
| | | | - Shih-Ling Huang
- Institute of Molecular Biology, Academia Sinica, Taipei 115, Taiwan
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22
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Nussbacher JK, Tabet R, Yeo GW, Lagier-Tourenne C. Disruption of RNA Metabolism in Neurological Diseases and Emerging Therapeutic Interventions. Neuron 2019; 102:294-320. [PMID: 30998900 DOI: 10.1016/j.neuron.2019.03.014] [Citation(s) in RCA: 158] [Impact Index Per Article: 31.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2018] [Revised: 01/24/2019] [Accepted: 03/12/2019] [Indexed: 02/06/2023]
Abstract
RNA binding proteins are critical to the maintenance of the transcriptome via controlled regulation of RNA processing and transport. Alterations of these proteins impact multiple steps of the RNA life cycle resulting in various molecular phenotypes such as aberrant RNA splicing, transport, and stability. Disruption of RNA binding proteins and widespread RNA processing defects are increasingly recognized as critical determinants of neurological diseases. Here, we describe distinct mechanisms by which the homeostasis of RNA binding proteins is compromised in neurological disorders through their reduced expression level, increased propensity to aggregate or sequestration by abnormal RNAs. These mechanisms all converge toward altered neuronal function highlighting the susceptibility of neurons to deleterious changes in RNA expression and the central role of RNA binding proteins in preserving neuronal integrity. Emerging therapeutic approaches to mitigate or reverse alterations of RNA binding proteins in neurological diseases are discussed.
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Affiliation(s)
- Julia K Nussbacher
- Department of Cellular and Molecular Medicine, Institute for Genomic Medicine, UCSD Stem Cell Program, University of California, San Diego, La Jolla, CA, USA
| | - Ricardos Tabet
- Department of Neurology, The Sean M. Healey and AMG Center for ALS at Mass General, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA 02129, USA; Broad Institute of Harvard University and MIT, Cambridge, MA 02142, USA
| | - Gene W Yeo
- Department of Cellular and Molecular Medicine, Institute for Genomic Medicine, UCSD Stem Cell Program, University of California, San Diego, La Jolla, CA, USA.
| | - Clotilde Lagier-Tourenne
- Department of Neurology, The Sean M. Healey and AMG Center for ALS at Mass General, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA 02129, USA; Broad Institute of Harvard University and MIT, Cambridge, MA 02142, USA.
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23
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Chen Y, Cohen TJ. Aggregation of the nucleic acid-binding protein TDP-43 occurs via distinct routes that are coordinated with stress granule formation. J Biol Chem 2019; 294:3696-3706. [PMID: 30630951 PMCID: PMC6416430 DOI: 10.1074/jbc.ra118.006351] [Citation(s) in RCA: 64] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2018] [Revised: 01/08/2019] [Indexed: 12/13/2022] Open
Abstract
TAR DNA-binding protein 43 (TDP-43) is a nucleic acid-binding protein, and its aggregation represents the defining pathology in amyotrophic lateral sclerosis (ALS) and related proteinopathies. Recent studies implicate cytoplasmic stress granules (SGs) as hubs that may facilitate TDP-43 aggregation. Here, using cellular fractionation, biochemical analyses, and histological assays, we show that TDP-43 targeted to the cytoplasm has multiple fates. Whereas a TDP-43 subpopulation is indeed recruited to SGs, mature aggregated TDP-43, produced with aggregate-prone TDP-43 variants or exposure to oxidative stress, generates distinct TDP-43 inclusions that are surprisingly devoid of SGs. Consistent with this observation, we found that SG components are predominantly excluded from TDP-43 pathology in motor neurons from individuals with ALS. We generated de novo SGs by expressing the fragile X protein (FMRP) and found that rather than directly engaging TDP-43 aggregates, SGs can sequester the proteostasis factor histone deacetylase 6 (HDAC6) and thereby impede TDP-43 clearance from cells. These findings indicate that SGs form distinct cytoplasmic structures that can indirectly enhance TDP-43 aggregation. Therapeutic approaches that inhibit SG formation may therefore be effective at suppressing TDP-43-mediated toxicity in patients with ALS and related TDP-43 proteinopathies.
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Affiliation(s)
- Youjun Chen
- From the Department of Neurology, University of North Carolina Neuroscience Center, University of North Carolina, Chapel Hill, North Carolina 27599
| | - Todd J Cohen
- From the Department of Neurology, University of North Carolina Neuroscience Center, University of North Carolina, Chapel Hill, North Carolina 27599
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24
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Mitra J, Guerrero EN, Hegde PM, Liachko NF, Wang H, Vasquez V, Gao J, Pandey A, Taylor JP, Kraemer BC, Wu P, Boldogh I, Garruto RM, Mitra S, Rao KS, Hegde ML. Motor neuron disease-associated loss of nuclear TDP-43 is linked to DNA double-strand break repair defects. Proc Natl Acad Sci U S A 2019; 116:4696-4705. [PMID: 30770445 PMCID: PMC6410842 DOI: 10.1073/pnas.1818415116] [Citation(s) in RCA: 184] [Impact Index Per Article: 36.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Genome damage and their defective repair have been etiologically linked to degenerating neurons in many subtypes of amyotrophic lateral sclerosis (ALS) patients; however, the specific mechanisms remain enigmatic. The majority of sporadic ALS patients feature abnormalities in the transactivation response DNA-binding protein of 43 kDa (TDP-43), whose nucleo-cytoplasmic mislocalization is characteristically observed in spinal motor neurons. While emerging evidence suggests involvement of other RNA/DNA binding proteins, like FUS in DNA damage response (DDR), the role of TDP-43 in DDR has not been investigated. Here, we report that TDP-43 is a critical component of the nonhomologous end joining (NHEJ)-mediated DNA double-strand break (DSB) repair pathway. TDP-43 is rapidly recruited at DSB sites to stably interact with DDR and NHEJ factors, specifically acting as a scaffold for the recruitment of break-sealing XRCC4-DNA ligase 4 complex at DSB sites in induced pluripotent stem cell-derived motor neurons. shRNA or CRISPR/Cas9-mediated conditional depletion of TDP-43 markedly increases accumulation of genomic DSBs by impairing NHEJ repair, and thereby, sensitizing neurons to DSB stress. Finally, TDP-43 pathology strongly correlates with DSB repair defects, and damage accumulation in the neuronal genomes of sporadic ALS patients and in Caenorhabditis elegans mutant with TDP-1 loss-of-function. Our findings thus link TDP-43 pathology to impaired DSB repair and persistent DDR signaling in motor neuron disease, and suggest that DSB repair-targeted therapies may ameliorate TDP-43 toxicity-induced genome instability in motor neuron disease.
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Affiliation(s)
- Joy Mitra
- Department of Radiation Oncology, Houston Methodist Research Institute, Houston, TX 77030
| | - Erika N Guerrero
- Department of Radiation Oncology, Houston Methodist Research Institute, Houston, TX 77030
- Center for Neuroscience, Instituto de Investigaciones Científicas y Servicios de Alta Tecnología, City of Knowledge, Panama, Republic of Panama
- Department of Biotechnology, Acharya Nagarjuna University, Guntur 522510, India
| | - Pavana M Hegde
- Department of Radiation Oncology, Houston Methodist Research Institute, Houston, TX 77030
| | - Nicole F Liachko
- Geriatric Research Education and Clinical Center, Veterans Affairs Puget Sound Health Care System, Seattle, WA 98108
- Division of Gerontology and Geriatric Medicine, Department of Medicine, University of Washington, Seattle, WA 98104
| | - Haibo Wang
- Department of Radiation Oncology, Houston Methodist Research Institute, Houston, TX 77030
- Institute of Academic Medicine, Houston Methodist Research Institute, Houston, TX 77030
| | - Velmarini Vasquez
- Department of Radiation Oncology, Houston Methodist Research Institute, Houston, TX 77030
- Center for Neuroscience, Instituto de Investigaciones Científicas y Servicios de Alta Tecnología, City of Knowledge, Panama, Republic of Panama
- Department of Biotechnology, Acharya Nagarjuna University, Guntur 522510, India
| | - Junling Gao
- Department of Neuroscience and Cell Biology, University of Texas Medical Branch, Galveston, TX 77555
| | - Arvind Pandey
- Department of Radiation Oncology, Houston Methodist Research Institute, Houston, TX 77030
| | - J Paul Taylor
- Department of Cell and Molecular Biology, St. Jude Children's Research Hospital, Memphis, TN 38105
- Howard Hughes Medical Institute, St. Jude Children's Research Hospital, Chevy Chase, MD 20815
| | - Brian C Kraemer
- Geriatric Research Education and Clinical Center, Veterans Affairs Puget Sound Health Care System, Seattle, WA 98108
- Division of Gerontology and Geriatric Medicine, Department of Medicine, University of Washington, Seattle, WA 98104
| | - Ping Wu
- Department of Neuroscience and Cell Biology, University of Texas Medical Branch, Galveston, TX 77555
| | - Istvan Boldogh
- Department of Microbiology and Immunology, University of Texas Medical Branch, Galveston, TX 77555
| | - Ralph M Garruto
- Department of Anthropology, Binghamton University, State University of New York, Binghamton, NY 13902;
- Department of Biological Sciences, Binghamton University, State University of New York, Binghamton, NY 13902
| | - Sankar Mitra
- Department of Radiation Oncology, Houston Methodist Research Institute, Houston, TX 77030
- Department of Radiation Oncology, Weill Medical College, New York, NY 10065
| | - K S Rao
- Center for Neuroscience, Instituto de Investigaciones Científicas y Servicios de Alta Tecnología, City of Knowledge, Panama, Republic of Panama
| | - Muralidhar L Hegde
- Department of Radiation Oncology, Houston Methodist Research Institute, Houston, TX 77030;
- Institute of Academic Medicine, Houston Methodist Research Institute, Houston, TX 77030
- Department of Radiation Oncology, Weill Medical College, New York, NY 10065
- Houston Methodist Neurological Institute, Houston Methodist Research Institute, Houston, TX 77030
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25
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Specchia V, Puricella A, D'Attis S, Massari S, Giangrande A, Bozzetti MP. Drosophila melanogaster as a Model to Study the Multiple Phenotypes, Related to Genome Stability of the Fragile-X Syndrome. Front Genet 2019; 10:10. [PMID: 30815010 PMCID: PMC6381874 DOI: 10.3389/fgene.2019.00010] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2018] [Accepted: 01/11/2019] [Indexed: 12/14/2022] Open
Abstract
Fragile-X syndrome is one of the most common forms of inherited mental retardation and autistic behaviors. The reduction/absence of the functional FMRP protein, coded by the X-linked Fmr1 gene in humans, is responsible for the syndrome. Patients exhibit a variety of symptoms predominantly linked to the function of FMRP protein in the nervous system like autistic behavior and mild-to-severe intellectual disability. Fragile-X (FraX) individuals also display cellular and morphological traits including branched dendritic spines, large ears, and macroorchidism. The dFmr1 gene is the Drosophila ortholog of the human Fmr1 gene. dFmr1 mutant flies exhibit synaptic abnormalities, behavioral defects as well as an altered germline development, resembling the phenotypes observed in FraX patients. Therefore, Drosophila melanogaster is considered a good model to study the physiopathological mechanisms underlying the Fragile-X syndrome. In this review, we explore how the multifaceted roles of the FMRP protein have been addressed in the Drosophila model and how the gained knowledge may open novel perspectives for understanding the molecular defects causing the disease and for identifying novel therapeutical targets.
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Affiliation(s)
- Valeria Specchia
- Dipartimento di Scienze e Tecnologie Biologiche ed Ambientali, DiSTeBA, Università del Salento, Lecce, Italy
| | - Antonietta Puricella
- Dipartimento di Scienze e Tecnologie Biologiche ed Ambientali, DiSTeBA, Università del Salento, Lecce, Italy
| | - Simona D'Attis
- Dipartimento di Scienze e Tecnologie Biologiche ed Ambientali, DiSTeBA, Università del Salento, Lecce, Italy
| | - Serafina Massari
- Dipartimento di Scienze e Tecnologie Biologiche ed Ambientali, DiSTeBA, Università del Salento, Lecce, Italy
| | - Angela Giangrande
- Institut de Génétique et de Biologie Moléculaire et Cellulaire, Illkirch, France.,Centre National de la Recherche Scientifique, UMR7104, Illkirch, France.,Institut National de la Santé et de la Recherche Médicale, U964, Illkirch, France.,Université de Strasbourg, Illkirch, France
| | - Maria Pia Bozzetti
- Dipartimento di Scienze e Tecnologie Biologiche ed Ambientali, DiSTeBA, Università del Salento, Lecce, Italy
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26
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Zhu LS, Wang DQ, Cui K, Liu D, Zhu LQ. Emerging Perspectives on DNA Double-strand Breaks in Neurodegenerative Diseases. Curr Neuropharmacol 2019; 17:1146-1157. [PMID: 31362659 PMCID: PMC7057204 DOI: 10.2174/1570159x17666190726115623] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2019] [Revised: 06/03/2019] [Accepted: 07/01/2019] [Indexed: 11/22/2022] Open
Abstract
DNA double-strand breaks (DSBs) are common events that were recognized as one of the most toxic lesions in eukaryotic cells. DSBs are widely involved in many physiological processes such as V(D)J recombination, meiotic recombination, DNA replication and transcription. Deregulation of DSBs has been reported in multiple diseases in human beings, such as the neurodegenerative diseases, with which the underlying mechanisms are needed to be illustrated. Here, we reviewed the recent insights into the dysfunction of DSB formation and repair, contributing to the pathogenesis of neurodegenerative disorders including Alzheimer's disease (AD), amyotrophic lateral sclerosis (ALS), Huntington's disease (HD) and ataxia telangiectasia (A-T).
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Affiliation(s)
| | | | | | | | - Ling-Qiang Zhu
- Address correspondence to this author at the Department of Neurosurgery, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei 430022, P.R. China; Tel: 862783692625; Fax: 862783692608; E-mail:
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27
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Angelova DM, Brown DR. Altered Processing of β-Amyloid in SH-SY5Y Cells Induced by Model Senescent Microglia. ACS Chem Neurosci 2018; 9:3137-3152. [PMID: 30052418 DOI: 10.1021/acschemneuro.8b00334] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
The single greatest risk factor for neurodegenerative diseases is aging. Aging of cells such as microglia in the nervous system has an impact not only on the ability of those cells to function but also on cells they interact with. We have developed a model microglia system that recapitulates the dystrophic/senescent phenotype, and we have combined this with the study of β-amyloid processing. The model is based on the observation that aged microglia have increased iron content. By overloading a human microglial cell line with iron, we were able to change the secretory profile of the microglia. When combining these senescent microglia with SH-SY5Y cells, we noted an increase in extracellular β-amyloid. The increased levels of β-amyloid were due to a decrease in the release of insulin-degrading enzyme by the model senescent microglia. Further analysis revealed that the senescent microglia showed both decreased autophagy and increased ER stress. These studies demonstrate the potential impact of an aging microglial population in terms of β-amyloid produced by neurons, which could play a causal role in diseases like Alzheimer's disease. Our results also further develop the potential utility of an in vitro model of senescent microglia for the study of brain aging and neurodegenerative disease.
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Affiliation(s)
- Dafina M. Angelova
- Department of Biology and Biochemistry, University of Bath, Bath BA2 7AY, U.K
| | - David R. Brown
- Department of Biology and Biochemistry, University of Bath, Bath BA2 7AY, U.K
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28
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Paul S, Dansithong W, Figueroa KP, Scoles DR, Pulst SM. Staufen1 links RNA stress granules and autophagy in a model of neurodegeneration. Nat Commun 2018; 9:3648. [PMID: 30194296 PMCID: PMC6128856 DOI: 10.1038/s41467-018-06041-3] [Citation(s) in RCA: 59] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2017] [Accepted: 07/17/2018] [Indexed: 11/26/2022] Open
Abstract
Spinocerebellar ataxia type 2 (SCA2) is a neurodegenerative disease caused by expansion of polyglutamine tract in the ATXN2 protein. We identified Staufen1 (STAU1) as an interactor of ATXN2, and showed elevation in cells from SCA2 patients, amyotrophic lateral sclerosis (ALS) patients, and in SCA2 mouse models. We demonstrated recruitment of STAU1 to mutant ATXN2 aggregates in brain tissue from patients with SCA2 human brain and in an SCA2 mouse model, and association of STAU1 elevation with dysregulation of SCA2-related transcript abundances. Targeting STAU1 in vitro by RNAi restored PCP2 transcript levels and lowering mutant ATXN2 also normalized STAU1 levels. Reduction of Stau1 in vivo improved motor behavior in an SCA2 mouse model, normalized the levels of several SCA2-related proteins, and reduced aggregation of polyglutamine-expanded ATXN2. These findings suggest a function for STAU1 in aberrant RNA metabolism associated with ATXN2 mutation, suggesting STAU1 is a possible novel therapeutic target for SCA2.
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Affiliation(s)
- Sharan Paul
- Department of Neurology, University of Utah, 175 North Medical Drive East, 5th Floor, Salt Lake City, Utah 84132, USA
| | - Warunee Dansithong
- Department of Neurology, University of Utah, 175 North Medical Drive East, 5th Floor, Salt Lake City, Utah 84132, USA
| | - Karla P Figueroa
- Department of Neurology, University of Utah, 175 North Medical Drive East, 5th Floor, Salt Lake City, Utah 84132, USA
| | - Daniel R Scoles
- Department of Neurology, University of Utah, 175 North Medical Drive East, 5th Floor, Salt Lake City, Utah 84132, USA
| | - Stefan M Pulst
- Department of Neurology, University of Utah, 175 North Medical Drive East, 5th Floor, Salt Lake City, Utah 84132, USA.
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29
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Khalil B, Morderer D, Price PL, Liu F, Rossoll W. mRNP assembly, axonal transport, and local translation in neurodegenerative diseases. Brain Res 2018; 1693:75-91. [PMID: 29462608 PMCID: PMC5997521 DOI: 10.1016/j.brainres.2018.02.018] [Citation(s) in RCA: 45] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2017] [Revised: 01/31/2018] [Accepted: 02/13/2018] [Indexed: 12/12/2022]
Abstract
The development, maturation, and maintenance of the mammalian nervous system rely on complex spatiotemporal patterns of gene expression. In neurons, this is achieved by the expression of differentially localized isoforms and specific sets of mRNA-binding proteins (mRBPs) that regulate RNA processing, mRNA trafficking, and local protein synthesis at remote sites within dendrites and axons. There is growing evidence that axons contain a specialized transcriptome and are endowed with the machinery that allows them to rapidly alter their local proteome via local translation and protein degradation. This enables axons to quickly respond to changes in their environment during development, and to facilitate axon regeneration and maintenance in adult organisms. Aside from providing autonomy to neuronal processes, local translation allows axons to send retrograde injury signals to the cell soma. In this review, we discuss evidence that disturbances in mRNP transport, granule assembly, axonal localization, and local translation contribute to pathology in various neurodegenerative diseases, including spinal muscular atrophy (SMA), amyotrophic lateral sclerosis (ALS), frontotemporal dementia (FTD), and Alzheimer's disease (AD).
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Affiliation(s)
- Bilal Khalil
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL 32224 USA
| | - Dmytro Morderer
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL 32224 USA
| | - Phillip L Price
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL 32224 USA; Department of Cell Biology, Emory University, Atlanta, GA 30322 USA
| | - Feilin Liu
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL 32224 USA; Eye Center, The Second Hospital of Jilin University, Changchun, Jilin 130021, China
| | - Wilfried Rossoll
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL 32224 USA.
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30
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Ferro D, Yao S, Zarnescu DC. Dynamic duo - FMRP and TDP-43: Regulating common targets, causing different diseases. Brain Res 2018; 1693:37-42. [PMID: 29715444 PMCID: PMC5997554 DOI: 10.1016/j.brainres.2018.04.034] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2017] [Revised: 04/24/2018] [Accepted: 04/26/2018] [Indexed: 10/17/2022]
Abstract
RNA binding proteins play essential roles during development and aging, and are also involved in disease pathomechanisms. RNA sequencing and omics analyses have provided a window into systems level alterations in neurological disease, and have identified RNA processing defects among notable disease mechanisms. This review focuses on two seemingly distinct neurological disorders, the RNA binding proteins they are linked to, and their newly discovered functional relationship. When deficient, Fragile X Mental Retardation Protein (FMRP) causes developmental deficits and autistic behaviors while TAR-DNA Binding Protein (TDP-43) dysregulation causes age dependent neuronal degeneration. Recent findings that FMRP and TDP-43 associate in ribonuclear protein particles and share mRNA targets in neurons highlight the critical importance of translation regulation in synaptic plasticity and provide new perspectives on neuronal vulnerability during lifespan.
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Affiliation(s)
- Diana Ferro
- Department of Molecular and Cellular Biology, University of Arizona, Tucson, AZ, United States
| | - Stephen Yao
- Department of Molecular and Cellular Biology, University of Arizona, Tucson, AZ, United States
| | - Daniela C Zarnescu
- Department of Molecular and Cellular Biology, University of Arizona, Tucson, AZ, United States; Department of Neuroscience, University of Arizona, Tucson, AZ, United States; Department of Neurology, University of Arizona, Tucson AZ, United States.
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31
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Tasaki S, Gaiteri C, Mostafavi S, Yu L, Wang Y, De Jager PL, Bennett DA. Multi-omic Directed Networks Describe Features of Gene Regulation in Aged Brains and Expand the Set of Genes Driving Cognitive Decline. Front Genet 2018; 9:294. [PMID: 30140277 PMCID: PMC6095043 DOI: 10.3389/fgene.2018.00294] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2018] [Accepted: 07/13/2018] [Indexed: 01/10/2023] Open
Abstract
Multiple aspects of molecular regulation, including genetics, epigenetics, and mRNA collectively influence the development of age-related neurologic diseases. Therefore, with the ultimate goal of understanding molecular systems associated with cognitive decline, we infer directed interactions among regulatory elements in the local regulatory vicinity of individual genes based on brain multi-omics data from 413 individuals. These local regulatory networks (LRNs) capture the influences of genetics and epigenetics on gene expression in older adults. LRNs were confirmed through correspondence to known transcription biophysics. To relate LRNs to age-related neurologic diseases, we then incorporate common neuropathologies and measures of cognitive decline into this framework. This step identifies a specific set of largely neuronal genes, such as STAU1 and SEMA3F, predicted to control cognitive decline in older adults. These predictions are validated in separate cohorts by comparison to genetic associations for general cognition. LRNs are shared through www.molecular.network on the Rush Alzheimer’s Disease Center Resource Sharing Hub (www.radc.rush.edu).
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Affiliation(s)
- Shinya Tasaki
- Rush Alzheimer's Disease Center, Rush University Medical Center, Chicago, IL, United States
| | - Chris Gaiteri
- Rush Alzheimer's Disease Center, Rush University Medical Center, Chicago, IL, United States
| | - Sara Mostafavi
- Department of Statistics, Department of Medical Genetics, University of British Columbia, Vancouver, BC, Canada
| | - Lei Yu
- Rush Alzheimer's Disease Center, Rush University Medical Center, Chicago, IL, United States
| | - Yanling Wang
- Rush Alzheimer's Disease Center, Rush University Medical Center, Chicago, IL, United States
| | - Philip L De Jager
- Center for Translational and Computational Neuroimmunology, Department of Neurology, Columbia University Medical Center, New York, NY, United States.,Cell Circuits Program, Broad Institute, Cambridge, MA, United States
| | - David A Bennett
- Rush Alzheimer's Disease Center, Rush University Medical Center, Chicago, IL, United States
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32
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Volkening K, Keller BA, Leystra-Lantz C, Strong MJ. RNA and Protein Interactors with TDP-43 in Human Spinal-Cord Lysates in Amyotrophic Lateral Sclerosis. J Proteome Res 2018. [DOI: 10.1021/acs.jproteome.8b00126] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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33
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Davis JK, Broadie K. Multifarious Functions of the Fragile X Mental Retardation Protein. Trends Genet 2017; 33:703-714. [PMID: 28826631 PMCID: PMC5610095 DOI: 10.1016/j.tig.2017.07.008] [Citation(s) in RCA: 81] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2017] [Revised: 07/20/2017] [Accepted: 07/24/2017] [Indexed: 01/01/2023]
Abstract
Fragile X syndrome (FXS), a heritable intellectual and autism spectrum disorder (ASD), results from the loss of Fragile X mental retardation protein (FMRP). This neurodevelopmental disease state exhibits neural circuit hyperconnectivity and hyperexcitability. Canonically, FMRP functions as an mRNA-binding translation suppressor, but recent findings have enormously expanded its proposed roles. Although connections between burgeoning FMRP functions remain unknown, recent advances have extended understanding of its involvement in RNA, channel, and protein binding that modulate calcium signaling, activity-dependent critical period development, and the excitation-inhibition (E/I) neural circuitry balance. In this review, we contextualize 3 years of FXS model research. Future directions extrapolated from recent advances focus on discovering links between FMRP roles to determine whether FMRP has a multitude of unrelated functions or whether combinatorial mechanisms can explain its multifaceted existence.
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Affiliation(s)
- Jenna K Davis
- Department of Biological Sciences, Kennedy Center for Research on Human Development, Vanderbilt University, Nashville, TN 37235, USA
| | - Kendal Broadie
- Department of Biological Sciences, Kennedy Center for Research on Human Development, Vanderbilt University, Nashville, TN 37235, USA.
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34
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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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35
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Novel Roles for Staufen1 in Embryonal and Alveolar Rhabdomyosarcoma via c-myc-dependent and -independent events. Sci Rep 2017; 7:42342. [PMID: 28211476 PMCID: PMC5314364 DOI: 10.1038/srep42342] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2016] [Accepted: 01/09/2017] [Indexed: 01/19/2023] Open
Abstract
Rhabdomyosarcoma is the most common soft tissue sarcoma in children and young adults. Rhabdomyosarcomas are skeletal muscle-like tumours that typically arise in muscle beds, and express key myogenic regulatory factors. However, their developmental program remains blocked in the proliferative phase with cells unable to exit the cell cycle to fuse into myotubes. Recently, we uncovered a key role for the RNA-binding protein Staufen1 during myogenic differentiation through the regulation of c-myc translation. Given the known implication of c-myc in rhabdomyosarcoma, we hypothesized in the current work that Staufen1 controls rhabdomyosarcoma tumorigenesis. Here, we report for the first time the novel role of Staufen1 in cancer, specifically in rhabdomyosarcoma. We demonstrate that Staufen1 is markedly upregulated in human rhabdomyosarcoma tumours and cell lines as compared to normal skeletal muscle. Moreover, we show that Staufen1 promotes the tumorigenesis of embryonal and alveolar rhabdomyosarcoma subtypes both in cell culture and in animal models. Finally, our data demonstrate that Staufen1 has differential roles in embryonal versus alveolar rhabdomyosarcoma through the control of proliferative and apoptotic pathways, respectively. Together, these results provide the first evidence for Staufen1’s direct implication in cancer biology. Accordingly, Staufen1 thus represents a novel target for the development of future therapeutic strategies for rhabdomyosarcoma.
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36
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Relationships between Stress Granules, Oxidative Stress, and Neurodegenerative Diseases. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2017; 2017:1809592. [PMID: 28194255 PMCID: PMC5286466 DOI: 10.1155/2017/1809592] [Citation(s) in RCA: 75] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/05/2016] [Accepted: 12/28/2016] [Indexed: 12/13/2022]
Abstract
Cytoplasmic stress granules (SGs) are critical for facilitating stress responses and for preventing the accumulation of misfolded proteins. SGs, however, have been linked to the pathogenesis of neurodegenerative diseases, in part because SGs share many components with neuronal granules. Oxidative stress is one of the conditions that induce SG formation. SGs regulate redox levels, and SG formation in turn is differently regulated by various types of oxidative stress. These associations and other evidences suggest that SG formation contributes to the development of neurodegenerative diseases. In this paper, we review the regulation of SG formation/assembly and discuss the interactions between oxidative stress and SG formation. We then discuss the links between SGs and neurodegenerative diseases and the current therapeutic approaches for neurodegenerative diseases that target SGs.
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37
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Could Sirtuin Activities Modify ALS Onset and Progression? Cell Mol Neurobiol 2016; 37:1147-1160. [PMID: 27942908 DOI: 10.1007/s10571-016-0452-2] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2016] [Accepted: 11/30/2016] [Indexed: 12/11/2022]
Abstract
Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease with a complex etiology. Sirtuins have been implicated as disease-modifying factors in several neurological disorders, and in the past decade, attempts have been made to check if manipulating Sirtuin activities and levels could confer benefit in terms of neuroprotection and survival in ALS models. The efforts have largely focused on mutant SOD1, and while limited in scope, the results were largely positive. Here, the body of work linking Sirtuins with ALS is reviewed, with discussions on how Sirtuins and their activities may impact on the major etiological mechanisms of ALS. Moving forward, it is important that the potentially beneficial effect of Sirtuins in ALS disease onset and progression are assessed in ALS models with TDP-43, FUS, and C9orf72 mutations.
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Majumder P, Chu JF, Chatterjee B, Swamy KBS, Shen CKJ. Co-regulation of mRNA translation by TDP-43 and Fragile X Syndrome protein FMRP. Acta Neuropathol 2016; 132:721-738. [PMID: 27518042 PMCID: PMC5073124 DOI: 10.1007/s00401-016-1603-8] [Citation(s) in RCA: 76] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2016] [Revised: 07/28/2016] [Accepted: 07/28/2016] [Indexed: 01/15/2023]
Abstract
For proper mammalian brain development and functioning, the translation of many neuronal mRNAs needs to be repressed without neuronal activity stimulations. We have discovered that the expression of a subclass of neuronal proteins essential for neurodevelopment and neuron plasticity is co-regulated at the translational level by TDP-43 and the Fragile X Syndrome protein FMRP. Using molecular, cellular and imaging approaches, we show that these two RNA-binding proteins (RBP) co-repress the translation initiation of Rac1, Map1b and GluR1 mRNAs, and consequently the hippocampal spinogenesis. The co-repression occurs through binding of TDP-43 to mRNA(s) at specific UG/GU sequences and recruitment of the inhibitory CYFIP1-FMRP complex by its glycine-rich domain. This novel regulatory scenario could be utilized to silence a significant portion of around 160 common target mRNAs of the two RBPs. The study establishes a functional/physical partnership between FMRP and TDP-43 that mechanistically links several neurodevelopmental disorders and neurodegenerative diseases.
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Ravel-Chapuis A, Klein Gunnewiek A, Bélanger G, Crawford Parks TE, Côté J, Jasmin BJ. Staufen1 impairs stress granule formation in skeletal muscle cells from myotonic dystrophy type 1 patients. Mol Biol Cell 2016; 27:1728-39. [PMID: 27030674 PMCID: PMC4884064 DOI: 10.1091/mbc.e15-06-0356] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2015] [Accepted: 03/25/2016] [Indexed: 11/11/2022] Open
Abstract
Myotonic dystrophy (DM1) is caused by an expansion of CUG repeats (CUG(exp)) in the DMPK mRNA 3'UTR. CUG(exp)-containing mRNAs become toxic to cells by misregulating RNA-binding proteins. Here we investigated the consequence of this RNA toxicity on the cellular stress response. We report that cell stress efficiently triggers formation of stress granules (SGs) in proliferating, quiescent, and differentiated muscle cells, as shown by the appearance of distinct cytoplasmic TIA-1- and DDX3-containing foci. We show that Staufen1 is also dynamically recruited into these granules. Moreover, we discovered that DM1 myoblasts fail to properly form SGs in response to arsenite. This blockage was not observed in DM1 fibroblasts, demonstrating a cell type-specific defect. DM1 myoblasts display increased expression and sequestration of toxic CUG(exp) mRNAs compared with fibroblasts. Of importance, down-regulation of Staufen1 in DM1 myoblasts rescues SG formation. Together our data show that Staufen1 participates in the inhibition of SG formation in DM1 myoblasts. These results reveal that DM1 muscle cells fail to properly respond to stress, thereby likely contributing to the complex pathogenesis of DM1.
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Affiliation(s)
- Aymeric Ravel-Chapuis
- Department of Cellular and Molecular Medicine and Centre for Neuromuscular Disease, Faculty of Medicine, University of Ottawa, Ottawa, ON K1H 8M5, Canada
| | - Amanda Klein Gunnewiek
- Department of Cellular and Molecular Medicine and Centre for Neuromuscular Disease, Faculty of Medicine, University of Ottawa, Ottawa, ON K1H 8M5, Canada
| | - Guy Bélanger
- Department of Cellular and Molecular Medicine and Centre for Neuromuscular Disease, Faculty of Medicine, University of Ottawa, Ottawa, ON K1H 8M5, Canada
| | - Tara E Crawford Parks
- Department of Cellular and Molecular Medicine and Centre for Neuromuscular Disease, Faculty of Medicine, University of Ottawa, Ottawa, ON K1H 8M5, Canada
| | - Jocelyn Côté
- Department of Cellular and Molecular Medicine and Centre for Neuromuscular Disease, Faculty of Medicine, University of Ottawa, Ottawa, ON K1H 8M5, Canada
| | - Bernard J Jasmin
- Department of Cellular and Molecular Medicine and Centre for Neuromuscular Disease, Faculty of Medicine, University of Ottawa, Ottawa, ON K1H 8M5, Canada
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Gershoni-Emek N, Mazza A, Chein M, Gradus-Pery T, Xiang X, Li KW, Sharan R, Perlson E. Proteomic Analysis of Dynein-Interacting Proteins in Amyotrophic Lateral Sclerosis Synaptosomes Reveals Alterations in the RNA-Binding Protein Staufen1. Mol Cell Proteomics 2015; 15:506-22. [PMID: 26598648 DOI: 10.1074/mcp.m115.049965] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2015] [Indexed: 12/12/2022] Open
Abstract
Synapse disruption takes place in many neurodegenerative diseases, including amyotrophic lateral sclerosis (ALS). However, the mechanistic understanding of this process is still limited. We set out to study a possible role for dynein in synapse integrity. Cytoplasmic dynein is a multisubunit intracellular molecule responsible for diverse cellular functions, including long-distance transport of vesicles, organelles, and signaling factors toward the cell center. A less well-characterized role dynein may play is the spatial clustering and anchoring of various factors including mRNAs in distinct cellular domains such as the neuronal synapse. Here, in order to gain insight into dynein functions in synapse integrity and disruption, we performed a screen for novel dynein interactors at the synapse. Dynein immunoprecipitation from synaptic fractions of the ALS model mSOD1(G93A) and wild-type controls, followed by mass spectrometry analysis on synaptic fractions of the ALS model mSOD1(G93A) and wild-type controls, was performed. Using advanced network analysis, we identified Staufen1, an RNA-binding protein required for the transport and localization of neuronal RNAs, as a major mediator of dynein interactions via its interaction with protein phosphatase 1-beta (PP1B). Both in vitro and in vivo validation assays demonstrate the interactions of Staufen1 and PP1B with dynein, and their colocalization with synaptic markers was altered as a result of two separate ALS-linked mutations: mSOD1(G93A) and TDP43(A315T). Taken together, we suggest a model in which dynein's interaction with Staufen1 regulates mRNA localization along the axon and the synapses, and alterations in this process may correlate with synapse disruption and ALS toxicity.
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Affiliation(s)
- Noga Gershoni-Emek
- From the ‡Sagol School of Neuroscience and Department of Physiology and Pharmacology, Sackler School of Medicine and
| | - Arnon Mazza
- §Blavatnik School of Computer Science, Tel Aviv University, Israel
| | - Michael Chein
- From the ‡Sagol School of Neuroscience and Department of Physiology and Pharmacology, Sackler School of Medicine and
| | - Tal Gradus-Pery
- From the ‡Sagol School of Neuroscience and Department of Physiology and Pharmacology, Sackler School of Medicine and
| | - Xin Xiang
- ¶Department of Biochemistry and Molecular Biology, the Uniformed Services University of Health Sciences, Bethesda, MD
| | - Ka Wan Li
- ‖Department of Molecular and Cellular Neurobiology, Center for Neurogenomics and Cognitive Research, Neuroscience Campus Amsterdam, VU University, Amsterdam, the Netherlands
| | - Roded Sharan
- §Blavatnik School of Computer Science, Tel Aviv University, Israel
| | - Eran Perlson
- From the ‡Sagol School of Neuroscience and Department of Physiology and Pharmacology, Sackler School of Medicine and
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41
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Coyne AN, Yamada SB, Siddegowda BB, Estes PS, Zaepfel BL, Johannesmeyer JS, Lockwood DB, Pham LT, Hart MP, Cassel JA, Freibaum B, Boehringer AV, Taylor JP, Reitz AB, Gitler AD, Zarnescu DC. Fragile X protein mitigates TDP-43 toxicity by remodeling RNA granules and restoring translation. Hum Mol Genet 2015; 24:6886-98. [PMID: 26385636 DOI: 10.1093/hmg/ddv389] [Citation(s) in RCA: 48] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2015] [Accepted: 09/14/2015] [Indexed: 12/12/2022] Open
Abstract
RNA dysregulation is a newly recognized disease mechanism in amyotrophic lateral sclerosis (ALS). Here we identify Drosophila fragile X mental retardation protein (dFMRP) as a robust genetic modifier of TDP-43-dependent toxicity in a Drosophila model of ALS. We find that dFMRP overexpression (dFMRP OE) mitigates TDP-43 dependent locomotor defects and reduced lifespan in Drosophila. TDP-43 and FMRP form a complex in flies and human cells. In motor neurons, TDP-43 expression increases the association of dFMRP with stress granules and colocalizes with polyA binding protein in a variant-dependent manner. Furthermore, dFMRP dosage modulates TDP-43 solubility and molecular mobility with overexpression of dFMRP resulting in a significant reduction of TDP-43 in the aggregate fraction. Polysome fractionation experiments indicate that dFMRP OE also relieves the translation inhibition of futsch mRNA, a TDP-43 target mRNA, which regulates neuromuscular synapse architecture. Restoration of futsch translation by dFMRP OE mitigates Futsch-dependent morphological phenotypes at the neuromuscular junction including synaptic size and presence of satellite boutons. Our data suggest a model whereby dFMRP is neuroprotective by remodeling TDP-43 containing RNA granules, reducing aggregation and restoring the translation of specific mRNAs in motor neurons.
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Affiliation(s)
- Alyssa N Coyne
- Department of Molecular and Cellular Biology, Department of Neuroscience
| | | | | | | | | | | | - Donovan B Lockwood
- Department of Molecular and Cellular Biology, Department of Neuroscience
| | - Linh T Pham
- Department of Molecular and Cellular Biology
| | - Michael P Hart
- Department of Genetics, Stanford University School of Medicine, Stanford, CA, USA
| | | | - Brian Freibaum
- Department of Neurobiology, St. Jude Children's Research Hospital, Memphis, TN, USA
| | - Ashley V Boehringer
- Department of Molecular and Cellular Biology, Department of Neuroscience, Department of Neurology, University of Arizona, Tucson, AZ, USA
| | - J Paul Taylor
- Department of Neurobiology, St. Jude Children's Research Hospital, Memphis, TN, USA
| | | | - Aaron D Gitler
- Department of Genetics, Stanford University School of Medicine, Stanford, CA, USA
| | - Daniela C Zarnescu
- Department of Molecular and Cellular Biology, Department of Neuroscience, Department of Neurology, University of Arizona, Tucson, AZ, USA,
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Proteomic analyses reveal that loss of TDP-43 affects RNA processing and intracellular transport. Neuroscience 2015; 293:157-70. [PMID: 25743254 DOI: 10.1016/j.neuroscience.2015.02.046] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2014] [Revised: 02/23/2015] [Accepted: 02/24/2015] [Indexed: 12/12/2022]
Abstract
Transactive response DNA-binding protein 43 (TDP-43) is a predominantly nuclear, ubiquitously expressed RNA and DNA-binding protein. It recognizes and binds to UG repeats and is involved in pre-mRNA splicing, mRNA stability and microRNA metabolism. TDP-43 is essential in early embryonic development but accumulates in cytoplasmic aggregates in amyotrophic lateral sclerosis (ALS) and tau-negative frontotemporal lobar degeneration (FTLD). It is not known yet whether cytoplasmic aggregates of TDP-43 are toxic or protective but they are often associated with a loss of TDP-43 from the nucleus and neurodegeneration may be caused by a loss of normal TDP-43 function or a gain of toxic function. Here we present a proteomic study to analyze the effect of loss of TDP-43 on the proteome. MS data are available via ProteomeXchange with identifier PXD001668. Our results indicate that TDP-43 is an important regulator of RNA metabolism and intracellular transport. We show that Ran-binding protein 1 (RanBP1), DNA methyltransferase 3 alpha (Dnmt3a) and chromogranin B (CgB) are downregulated upon TDP-43 knockdown. Subsequently, transportin 1 level is increased as a result of RanBP1 depletion. Improper regulation of these proteins and the subsequent disruption of cellular processes may play a role in the pathogenesis of the TDP-43 proteinopathies ALS and FTLD.
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Mohan M, Kumar V, Lackner AA, Alvarez X. Dysregulated miR-34a-SIRT1-acetyl p65 axis is a potential mediator of immune activation in the colon during chronic simian immunodeficiency virus infection of rhesus macaques. THE JOURNAL OF IMMUNOLOGY 2014; 194:291-306. [PMID: 25452565 DOI: 10.4049/jimmunol.1401447] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Persistent gastrointestinal inflammation, a hallmark of progressive HIV/SIV infection, causes disruption of the gastrointestinal epithelial barrier, microbial translocation, and generalized immune activation/inflammation driving AIDS progression. Apart from protein regulators, recent studies strongly suggest critical roles for microRNAs (miRNAs) in regulating and managing certain aspects of the inflammatory process. To examine their immunoregulatory role, we profiled miRNA expression in the colon from 12 chronic SIV-infected and 4 control macaques. After applying multiple comparisons correction, 10 (3 upregulated and 7 downregulated) miRNAs showed differential expression. Most notably, miR-34a showed significant upregulation in both epithelial and lamina propria leukocyte (LPL) compartments. Intense γH2A.X expression in colonic epithelium and LPLs confirmed the contribution of DNA damage response in driving miR-34a upregulation. SIRT1 mRNA and protein decreased significantly in both colonic epithelium and LPLs. Luciferase reporter assays validated rhesus macaque SIRT1 as a direct miR-34a target. Decreased SIRT1 expression was associated with constitutively enhanced expression of the transcriptionally active form of the p65 (acetylated on lysine 310) subunit of NF-κB exclusively in the LPL compartment. The intensity and number of acetylated p65(+) cells was markedly elevated in LPLs of chronically SIV-infected macaques compared with uninfected controls and localized to increased numbers of IgA(+) and IgG(+) plasma cells. These findings provide new insights into the potential role of the miR-34a-SIRT1-p65 axis in causing hyperactivation of the intestinal B cell system. Our results point to a possible mechanism where the normal immunosuppressive function of SIRT1 is inhibited by elevated miR-34a expression resulting in constitutive activation of acetylated p65 (lysine 310).
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Affiliation(s)
- Mahesh Mohan
- Division of Comparative Pathology, Tulane National Primate Research Center, Covington, LA 70433
| | - Vinay Kumar
- Division of Comparative Pathology, Tulane National Primate Research Center, Covington, LA 70433
| | - Andrew A Lackner
- Division of Comparative Pathology, Tulane National Primate Research Center, Covington, LA 70433
| | - Xavier Alvarez
- Division of Comparative Pathology, Tulane National Primate Research Center, Covington, LA 70433
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44
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Trinucleotide expansion in disease: why is there a length threshold? Curr Opin Genet Dev 2014; 26:131-40. [PMID: 25282113 DOI: 10.1016/j.gde.2014.07.003] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2014] [Accepted: 07/21/2014] [Indexed: 11/24/2022]
Abstract
Trinucleotide repeats (TNRs) expansion disorders are severe neurodegenerative and neuromuscular disorders that arise from inheriting a long tract (30-50 copies) of a trinucleotide unit within or near an expressed gene (Figure 1a). The mutation is referred to as 'trinucleotide expansion' since the number of triplet units in a mutated gene is greater than the number found in the normal gene. Expansion becomes obvious once the number of repeating units passes a critical threshold length, but what happens at the threshold to render the repeating tract unstable? Here we discuss DNA-dependent and RNA-dependent models by which a particular DNA length permits a rapid transition to an unstable state.
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45
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Heraud-Farlow JE, Kiebler MA. The multifunctional Staufen proteins: conserved roles from neurogenesis to synaptic plasticity. Trends Neurosci 2014; 37:470-9. [PMID: 25012293 PMCID: PMC4156307 DOI: 10.1016/j.tins.2014.05.009] [Citation(s) in RCA: 75] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2014] [Revised: 05/22/2014] [Accepted: 05/27/2014] [Indexed: 12/11/2022]
Abstract
Staufen (Stau) proteins have evolutionarily conserved functions in the brain. Stau proteins asymmetrically segregate mRNAs during mouse and fly neurogenesis. Stau proteins regulate synaptic plasticity and memory formation in flies and mammals. Stau proteins have roles in translation, localisation, and ribonucleoprotein formation. New data indicate that mammalian Stau1 and Stau2 can both stabilise and destabilise target mRNAs.
Staufen (Stau) proteins belong to a family of RNA-binding proteins (RBPs) that are important for RNA localisation in many organisms. In this review we discuss recent findings on the conserved role played by Stau during both the early differentiation of neurons and in the synaptic plasticity of mature neurons. Recent molecular data suggest mechanisms for how Stau2 regulates mRNA localisation, mRNA stability, translation, and ribonucleoprotein (RNP) assembly. We offer a perspective on how this multifunctional RBP has been adopted to regulate mRNA localisation under several different cellular and developmental conditions.
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Affiliation(s)
- Jacki E Heraud-Farlow
- Department of Chromosome Biology, Max F. Perutz Laboratories, University of Vienna, 1030 Vienna, Austria
| | - Michael A Kiebler
- Department of Anatomy and Cell Biology, Ludwig-Maximilians-University, 80336 Munich, Germany.
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46
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Hans F, Fiesel FC, Strong JC, Jäckel S, Rasse TM, Geisler S, Springer W, Schulz JB, Voigt A, Kahle PJ. UBE2E ubiquitin-conjugating enzymes and ubiquitin isopeptidase Y regulate TDP-43 protein ubiquitination. J Biol Chem 2014; 289:19164-79. [PMID: 24825905 DOI: 10.1074/jbc.m114.561704] [Citation(s) in RCA: 64] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Trans-activation element DNA-binding protein of 43 kDa (TDP-43) characterizes insoluble protein aggregates in distinct subtypes of frontotemporal lobar degeneration and amyotrophic lateral sclerosis. TDP-43 mediates many RNA processing steps within distinct protein complexes. Here we identify novel TDP-43 protein interactors found in a yeast two-hybrid screen using an adult human brain cDNA library. We confirmed the TDP-43 interaction of seven hits by co-immunoprecipitation and assessed their co-localization in HEK293E cells. As pathological TDP-43 is ubiquitinated, we focused on the ubiquitin-conjugating enzyme UBE2E3 and the ubiquitin isopeptidase Y (UBPY). When cells were treated with proteasome inhibitor, ubiquitinated and insoluble TDP-43 species accumulated. All three UBE2E family members could enhance the ubiquitination of TDP-43, whereas catalytically inactive UBE2E3(C145S) was much less efficient. Conversely, silencing of UBE2E3 reduced TDP-43 ubiquitination. We examined 15 of the 48 known disease-associated TDP-43 mutants and found that one was excessively ubiquitinated. This strong TDP-43(K263E) ubiquitination was further enhanced by proteasomal inhibition as well as UBE2E3 expression. Conversely, UBE2E3 silencing and expression of UBPY reduced TDP-43(K263E) ubiquitination. Moreover, wild-type but not active site mutant UBPY reduced ubiquitination of TDP-43 C-terminal fragments and of a nuclear import-impaired mutant. In Drosophila melanogaster, UBPY silencing enhanced neurodegenerative TDP-43 phenotypes and the accumulation of insoluble high molecular weight TDP-43 and ubiquitin species. Thus, UBE2E3 and UBPY participate in the regulation of TDP-43 ubiquitination, solubility, and neurodegeneration.
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Affiliation(s)
- Friederike Hans
- From the Graduate School of Cellular and Molecular Neuroscience, University of Tübingen, Tübingen 72076, Germany, Laboratory of Functional Neurogenetics, Department of Neurodegeneration, German Center for Neurodegenerative Diseases (DZNE), Tübingen 72076, Germany, Laboratory of Functional Neurogenetics, Department of Neurodegeneration and
| | - Fabienne C Fiesel
- Laboratory of Functional Neurogenetics, Department of Neurodegeneration and
| | - Jennifer C Strong
- Laboratory of Functional Neurogenetics, Department of Neurodegeneration and
| | - Sandra Jäckel
- Laboratory of Functional Neurogenetics, Department of Neurodegeneration and
| | - Tobias M Rasse
- Synaptic Plasticity Group, Hertie Institute for Clinical Brain Research, Tübingen 72076, Germany
| | - Sven Geisler
- Laboratory of Functional Neurogenetics, Department of Neurodegeneration and
| | - Wolfdieter Springer
- Laboratory of Functional Neurogenetics, Department of Neurodegeneration, German Center for Neurodegenerative Diseases (DZNE), Tübingen 72076, Germany, Laboratory of Functional Neurogenetics, Department of Neurodegeneration and
| | - Jörg B Schulz
- Department of Neurology, University Medical Center, Aachen 52074, Germany, and Jülich Aachen Research Alliance (JARA)-Translational Brain Medicine, Aachen 52074, Germany
| | - Aaron Voigt
- Department of Neurology, University Medical Center, Aachen 52074, Germany, and
| | - Philipp J Kahle
- From the Graduate School of Cellular and Molecular Neuroscience, University of Tübingen, Tübingen 72076, Germany, Laboratory of Functional Neurogenetics, Department of Neurodegeneration, German Center for Neurodegenerative Diseases (DZNE), Tübingen 72076, Germany, Laboratory of Functional Neurogenetics, Department of Neurodegeneration and
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47
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Lenzken SC, Achsel T, Carrì MT, Barabino SML. Neuronal RNA-binding proteins in health and disease. WILEY INTERDISCIPLINARY REVIEWS-RNA 2014; 5:565-76. [PMID: 24687864 DOI: 10.1002/wrna.1231] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/06/2013] [Revised: 02/25/2014] [Accepted: 02/26/2014] [Indexed: 12/12/2022]
Abstract
In mammalian cells in general and in neurons in particular, mRNA maturation, translation, and degradation are highly complex and dynamic processes. RNA-binding proteins (RBPs) play crucial roles in all these events. First, they participate in the choice of pre-mRNA splice sites and in the selection of the polyadenylation sites, determining which of the possible isoforms is produced from a given precursor mRNA. Then, once in the cytoplasm, the protein composition of the RNP particles determines whether the mature mRNA is transported along the dendrites or the axon of a neuron to the synapses, how efficiently it is translated, and how stable it is. In agreement with their importance for neuronal function, mutations in genes that code for RBPs are associated with various neurological diseases. In this review, we illustrate how individual RBPs determine the fate of an mRNA, and we discuss how mutations in RBPs or perturbations of the mRNA metabolism can cause neurodegenerative disorders.
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48
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Budini M, Baralle FE, Buratti E. Targeting TDP-43 in neurodegenerative diseases. Expert Opin Ther Targets 2014; 18:617-32. [DOI: 10.1517/14728222.2014.896905] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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49
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Di Liegro CM, Schiera G, Di Liegro I. Regulation of mRNA transport, localization and translation in the nervous system of mammals (Review). Int J Mol Med 2014; 33:747-62. [PMID: 24452120 PMCID: PMC3976132 DOI: 10.3892/ijmm.2014.1629] [Citation(s) in RCA: 81] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2013] [Accepted: 12/09/2013] [Indexed: 12/13/2022] Open
Abstract
Post-transcriptional control of mRNA trafficking and metabolism plays a critical role in the actualization and fine tuning of the genetic program of cells, both in development and in differentiated tissues. Cis-acting signals, responsible for post-transcriptional regulation, reside in the RNA message itself, usually in untranslated regions, 5′ or 3′ to the coding sequence, and are recognized by trans-acting factors: RNA-binding proteins (RBPs) and/or non-coding RNAs (ncRNAs). ncRNAs bind short mRNA sequences usually present in the 3′-untranslated (3′-UTR) region of their target messages. RBPs recognize specific nucleotide sequences and/or secondary/tertiary structures. Most RBPs assemble on mRNA at the moment of transcription and shepherd it to its destination, somehow determining its final fate. Regulation of mRNA localization and metabolism has a particularly important role in the nervous system where local translation of pre-localized mRNAs has been implicated in developing axon and dendrite pathfinding, and in synapse formation. Moreover, activity-dependent mRNA trafficking and local translation may underlie long-lasting changes in synaptic efficacy, responsible for learning and memory. This review focuses on the role of RBPs in neuronal development and plasticity, as well as possible connections between ncRNAs and RBPs.
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Affiliation(s)
- Carlo Maria Di Liegro
- Department of Biological Chemical and Pharmaceutical Sciences and Technologies (STEBICEF), I-90128 Palermo, Italy
| | - Gabriella Schiera
- Department of Biological Chemical and Pharmaceutical Sciences and Technologies (STEBICEF), I-90128 Palermo, Italy
| | - Italia Di Liegro
- Department of Experimental Biomedicine and Clinical Neurosciences (BIONEC), University of Palermo, I-90127 Palermo, Italy
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50
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Chaudhuri AD, Yelamanchili SV, Marcondes MCG, Fox HS. Up-regulation of microRNA-142 in simian immunodeficiency virus encephalitis leads to repression of sirtuin1. FASEB J 2013; 27:3720-9. [PMID: 23752207 DOI: 10.1096/fj.13-232678] [Citation(s) in RCA: 56] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
MicroRNA (miR)-142 is up-regulated in the brain in HIV and SIV encephalitis (SIVE). We identified the cell types where miR-142 is up-regulated and its relevant downstream target. Fluorescent in situ hybridization combined with immunofluorescent labeling revealed that miR-142-3p and -5p are expressed within hippocampal neurons and myeloid cells in SIVE. Sirtuin1 (SIRT1) was predicted as a potential miR-142 target by analysis of its 3'-UTR and bioinformatic analysis of factors linked to altered hippocampal gene expression profile in SIVE. Overexpression of pre-miR-142 in HEK293T cells led to a 3.7-fold decrease in SIRT1 protein level. Examination of the individual effects of miR-142-5p and miR-142-3p through overexpression and inhibition studies revealed that significant effects on SIRT1 occurred only with miR-142-5p. Luciferase reporter assays revealed a 2.3-fold inhibition of expression due to interaction of miR-142 with the SIRT1 3'-UTR, mutation analysis revealed that only the miR-142-5p target site was active. MiR-142 expression in primary human neurons led to a small (1.3-fold) but significant decrease in SIRT1 protein level. Furthermore, qRT-PCR revealed up-regulation of miR-142-3p (6.4-fold) and -5p (3.9-fold) and down-regulation of SIRT1 (33-fold) in macrophages/microglia from animals with SIVE. We have therefore elucidated a miR-mediated mechanism of regulation of SIRT1 expression in SIVE.
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Affiliation(s)
- Amrita Datta Chaudhuri
- Department of Pharmacology and Experimental Neuroscience, University of Nebraska Medical Center, Omaha, NE 68198-5800, USA
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