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Everest E, Gulec B, Uygunoglu U. A Case of Coexistent Spinocerebellar Ataxia Type 2 and Primary Progressive Multiple Sclerosis-Coincidental or Associated? Cerebellum 2024; 23:1235-1238. [PMID: 37715888 DOI: 10.1007/s12311-023-01605-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 09/11/2023] [Indexed: 09/18/2023]
Abstract
Spinocerebellar ataxia type 2 (SCA2) is a dominantly inherited ataxia primarily characterised by progressive cerebellar syndrome, which is developed due to the expansion of the CAG trinucleotide repeat within the first exon of the ATXN2 gene. We report a rare case of a 41-year-old woman with coexistent genetically verified SCA2 and primary progressive multiple sclerosis (MS). Considering our case and a few others reported in the literature, as well as a possible genetic association between ATXN2 and MS susceptibility, we suggest that the coexistence of SCA and MS may not be coincidental, especially in patients with a progressive MS course.
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Affiliation(s)
- Elif Everest
- Department of Neurology, Cerrahpasa Medical Faculty, Istanbul University-Cerrahpasa, Istanbul, Turkey
| | - Bade Gulec
- Department of Neurology, Cerrahpasa Medical Faculty, Istanbul University-Cerrahpasa, Istanbul, Turkey
| | - Ugur Uygunoglu
- Department of Neurology, Cerrahpasa Medical Faculty, Istanbul University-Cerrahpasa, Istanbul, Turkey.
- Neuroimmunology Division, Institute of Neurological Sciences, Cerrahpasa Medical Faculty, Istanbul University-Cerrahpasa, Istanbul, Turkey.
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2
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Capacci E, Bagnoli S, Giacomucci G, Rapillo CM, Govoni A, Bessi V, Polito C, Giotti I, Brogi A, Pelo E, Sorbi S, Nacmias B, Ferrari C. The Frequency of Intermediate Alleles in Patients with Cerebellar Phenotypes. Cerebellum 2024; 23:1135-1145. [PMID: 37906407 PMCID: PMC11102406 DOI: 10.1007/s12311-023-01620-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 10/13/2023] [Indexed: 11/02/2023]
Abstract
Cerebellar syndromes are clinically and etiologically heterogeneous and can be classified as hereditary, neurodegenerative non-hereditary, or acquired. Few data are available on the frequency of each form in the clinical setting. Growing interest is emerging regarding the genetic forms caused by triplet repeat expansions. Alleles with repeat expansion lower than the pathological threshold, termed intermediate alleles (IAs), have been found to be associated with disease manifestation. In order to assess the relevance of IAs as a cause of cerebellar syndromes, we enrolled 66 unrelated Italian ataxic patients and described the distribution of the different etiology of their syndromes and the frequency of IAs. Each patient underwent complete clinical, hematological, and neurophysiological assessments, neuroimaging evaluations, and genetic tests for autosomal dominant cerebellar ataxia (SCA) and fragile X-associated tremor/ataxia syndrome (FXTAS). We identified the following diagnostic categories: 28% sporadic adult-onset ataxia, 18% cerebellar variant of multiple system atrophy, 9% acquired forms, 9% genetic forms with full-range expansion, and 12% cases with intermediate-range expansion. The IAs were six in the FMR1 gene, two in the gene responsible for SCA8, and one in the ATXN2 gene. The clinical phenotype of patients carrying the IAs resembles, in most of the cases, the one associated with full-range expansion. Our study provides an exhaustive description of the causes of cerebellar ataxia, estimating for the first time the frequency of IAs in SCAs- and FXTAS-associated genes. The high percentage of cases with IAs supports further screening among patients with cerebellar syndromes.
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Affiliation(s)
- Elena Capacci
- Department of Neuroscience, Psychology, Drug Research and Child Health (NEUROFARBA), University of Florence, Florence, Italy
| | - Silvia Bagnoli
- Department of Neuroscience, Psychology, Drug Research and Child Health (NEUROFARBA), University of Florence, Florence, Italy
| | - Giulia Giacomucci
- Department of Neuroscience, Psychology, Drug Research and Child Health (NEUROFARBA), University of Florence, Florence, Italy
| | - Costanza Maria Rapillo
- Department of Neuroscience, Psychology, Drug Research and Child Health (NEUROFARBA), University of Florence, Florence, Italy
| | - Alessandra Govoni
- Neuromuscular-Skeletal and Sensory Organs Department, AOU Careggi, Florence, Italy
| | - Valentina Bessi
- Department of Neuroscience, Psychology, Drug Research and Child Health (NEUROFARBA), University of Florence, Florence, Italy
| | | | - Irene Giotti
- SODc Diagnostica Genetica, Azienda Ospedaliero Universitaria Careggi, Florence, Italy
| | - Alice Brogi
- SODc Diagnostica Genetica, Azienda Ospedaliero Universitaria Careggi, Florence, Italy
| | - Elisabetta Pelo
- SODc Diagnostica Genetica, Azienda Ospedaliero Universitaria Careggi, Florence, Italy
| | - Sandro Sorbi
- Department of Neuroscience, Psychology, Drug Research and Child Health (NEUROFARBA), University of Florence, Florence, Italy
- IRCCS Fondazione Don Carlo Gnocchi, Florence, Italy
| | - Benedetta Nacmias
- Department of Neuroscience, Psychology, Drug Research and Child Health (NEUROFARBA), University of Florence, Florence, Italy
- IRCCS Fondazione Don Carlo Gnocchi, Florence, Italy
| | - Camilla Ferrari
- Department of Neuroscience, Psychology, Drug Research and Child Health (NEUROFARBA), University of Florence, Florence, Italy.
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3
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Seemann J, Daghsen L, Cazier M, Lamy JC, Welter ML, Giese MA, Synofzik M, Durr A, Ilg W, Coarelli G. Digital Gait Measures Capture 1-Year Progression in Early-Stage Spinocerebellar Ataxia Type 2. Mov Disord 2024; 39:788-797. [PMID: 38419144 DOI: 10.1002/mds.29757] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2023] [Revised: 01/29/2024] [Accepted: 02/02/2024] [Indexed: 03/02/2024] Open
Abstract
BACKGROUND With disease-modifying drugs in reach for cerebellar ataxias, fine-grained digital health measures are highly warranted to complement clinical and patient-reported outcome measures in upcoming treatment trials and treatment monitoring. These measures need to demonstrate sensitivity to capture change, in particular in the early stages of the disease. OBJECTIVE Our aim is to unravel gait measures sensitive to longitudinal change in the-particularly trial-relevant-early stage of spinocerebellar ataxia type 2 (SCA2). METHODS We performed a multicenter longitudinal study with combined cross-sectional and 1-year interval longitudinal analysis in early-stage SCA2 participants (n = 23, including nine pre-ataxic expansion carriers; median, ATXN2 CAG repeat expansion 38 ± 2; median, Scale for the Assessment and Rating of Ataxia [SARA] score 4.8 ± 4.3). Gait was assessed using three wearable motion sensors during a 2-minute walk, with analyses focused on gait measures of spatio-temporal variability that have shown sensitivity to ataxia severity (eg, lateral step deviation). RESULTS We found significant changes for gait measures between baseline and 1-year follow-up with large effect sizes (lateral step deviation P = 0.0001, effect size rprb = 0.78), whereas the SARA score showed no change (P = 0.67). Sample size estimation indicates a required cohort size of n = 43 to detect a 50% reduction in natural progression. Test-retest reliability and minimal detectable change analysis confirm the accuracy of detecting 50% of the identified 1-year change. CONCLUSIONS Gait measures assessed by wearable sensors can capture natural progression in early-stage SCA2 within just 1 year-in contrast to a clinical ataxia outcome. Lateral step deviation represents a promising outcome measure for upcoming multicenter interventional trials, particularly in the early stages of cerebellar ataxia. © 2024 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.
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Affiliation(s)
- Jens Seemann
- Section Computational Sensomotorics, Hertie Institute for Clinical Brain Research, University of Tübingen, Tübingen, Germany
- Centre for Integrative Neuroscience (CIN), Tübingen, Germany
| | - Lina Daghsen
- Sorbonne Université, Paris Brain Institute-ICM, Inserm, CNRS, AP-HP, Paris, France
| | - Matthieu Cazier
- Sorbonne Université, Paris Brain Institute-ICM, Inserm, CNRS, AP-HP, Paris, France
| | - Jean-Charles Lamy
- Sorbonne Université, Paris Brain Institute-ICM, Inserm, CNRS, AP-HP, Paris, France
| | - Marie-Laure Welter
- Sorbonne Université, Paris Brain Institute-ICM, Inserm, CNRS, AP-HP, Paris, France
| | - Martin A Giese
- Section Computational Sensomotorics, Hertie Institute for Clinical Brain Research, University of Tübingen, Tübingen, Germany
- Centre for Integrative Neuroscience (CIN), Tübingen, Germany
| | - Matthis Synofzik
- Division Translational Genomics of Neurodegenerative Diseases, Hertie-Institute for Clinical Brain Research and Center of Neurology, University of Tübingen, Tübingen, Germany
- German Center for Neurodegenerative Diseases (DZNE), Tübingen, Germany
| | - Alexandra Durr
- Sorbonne Université, Paris Brain Institute-ICM, Inserm, CNRS, AP-HP, Paris, France
| | - Winfried Ilg
- Section Computational Sensomotorics, Hertie Institute for Clinical Brain Research, University of Tübingen, Tübingen, Germany
- Centre for Integrative Neuroscience (CIN), Tübingen, Germany
| | - Giulia Coarelli
- Sorbonne Université, Paris Brain Institute-ICM, Inserm, CNRS, AP-HP, Paris, France
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4
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Liu YJ, Wang JY, Zhang XL, Jiang LL, Hu HY. Ataxin-2 sequesters Raptor into aggregates and impairs cellular mTORC1 signaling. FEBS J 2024; 291:1795-1812. [PMID: 38308810 DOI: 10.1111/febs.17081] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2023] [Revised: 11/28/2023] [Accepted: 01/26/2024] [Indexed: 02/05/2024]
Abstract
Ataxin-2 (Atx2) is a polyglutamine (polyQ) protein, in which abnormal expansion of the polyQ tract can trigger protein aggregation and consequently cause spinocerebellar ataxia type 2 (SCA2), but the mechanism underlying how Atx2 aggregation leads to proteinopathy remains elusive. Here, we investigate the molecular mechanism and cellular consequences of Atx2 aggregation by molecular cell biology approaches. We have revealed that either normal or polyQ-expanded Atx2 can sequester Raptor, a component of mammalian target of rapamycin complex 1 (mTORC1), into aggregates based on their specific interaction. Further research indicates that the polyQ tract and the N-terminal region (residues 1-784) of Atx2 are responsible for the specific sequestration. Moreover, this sequestration leads to suppression of the mTORC1 activity as represented by down-regulation of phosphorylated P70S6K, which can be reversed by overexpression of Raptor. As mTORC1 is a key regulator of autophagy, Atx2 aggregation and sequestration also induces autophagy by upregulating LC3-II and reducing phosphorylated ULK1 levels. This study proposes that Atx2 sequesters Raptor into aggregates, thereby impairing cellular mTORC1 signaling and inducing autophagy, and will be beneficial for a better understanding of the pathogenesis of SCA2 and other polyQ diseases.
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Affiliation(s)
- Ya-Jun Liu
- State Key Laboratory of Molecular Biology, Shanghai Institute of Biochemistry and Cell Biology, Center for Excellence in Molecular Cell Science, Chinese Academy of Sciences, Shanghai, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Jian-Yang Wang
- State Key Laboratory of Molecular Biology, Shanghai Institute of Biochemistry and Cell Biology, Center for Excellence in Molecular Cell Science, Chinese Academy of Sciences, Shanghai, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Xiang-Le Zhang
- State Key Laboratory of Molecular Biology, Shanghai Institute of Biochemistry and Cell Biology, Center for Excellence in Molecular Cell Science, Chinese Academy of Sciences, Shanghai, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Lei-Lei Jiang
- State Key Laboratory of Molecular Biology, Shanghai Institute of Biochemistry and Cell Biology, Center for Excellence in Molecular Cell Science, Chinese Academy of Sciences, Shanghai, China
| | - Hong-Yu Hu
- State Key Laboratory of Molecular Biology, Shanghai Institute of Biochemistry and Cell Biology, Center for Excellence in Molecular Cell Science, Chinese Academy of Sciences, Shanghai, China
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5
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Chitre M, Emery P. ATXN2 is a target of N-terminal proteolysis. PLoS One 2023; 18:e0296085. [PMID: 38128014 PMCID: PMC10735043 DOI: 10.1371/journal.pone.0296085] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2023] [Accepted: 12/04/2023] [Indexed: 12/23/2023] Open
Abstract
Spinocerebellar ataxia 2 (SCA2) is a neurodegenerative disorder caused by the expansion of the poly-glutamine (polyQ) tract of Ataxin-2 (ATXN2). Other polyQ-containing proteins such as ATXN7 and huntingtin are associated with the development of neurodegenerative diseases when their N-terminal polyQ domains are expanded. Furthermore, they undergo proteolytic processing events that produce N-terminal fragments that include the polyQ stretch, which are implicated in pathogenesis. Interestingly, N-terminal ATXN2 fragments were reported in a brain extract from a SCA2 patient, but it is currently unknown whether an expanded polyQ domain contributes to ATXN2 proteolytic susceptibility. Here, we used transient expression in HEK293 cells to determine whether ATXN2 is a target for specific N-terminal proteolysis. We found that ATXN2 proteins with either normal or expanded polyQ stretches undergo proteolytic cleavage releasing an N-terminal polyQ-containing fragment. We identified a short amino acid sequence downstream of the polyQ domain that is necessary for N-terminal cleavage of full-length ATXN2 and sufficient to induce proteolysis of a heterologous protein. However, this sequence is not required for cleavage of a short ATXN2 isoform produced from an alternative start codon located just upstream of the CAG repeats encoding the polyQ domain. Our study extends our understanding of ATXN2 posttranslational regulation by revealing that this protein can be the target of specific proteolytic cleavage events releasing polyQ-containing products that are modulated by the N-terminal domain of ATXN2. N-terminal ATXN2 proteolysis of expanded polyQ domains might contribute to SCA2 pathology, as observed in other neurodegenerative disorders caused by polyQ domain expansion.
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Affiliation(s)
- Monika Chitre
- Department of Neurobiology, University of Massachusetts Chan Medical School, Worcester, Massachusetts, United States of America
- Interdisciplinary Graduate Program, Morningside Graduate School of Biomedical Sciences, University of Massachusetts Chan Medical School, Worcester, Massachusetts, United States of America
| | - Patrick Emery
- Department of Neurobiology, University of Massachusetts Chan Medical School, Worcester, Massachusetts, United States of America
- Interdisciplinary Graduate Program, Morningside Graduate School of Biomedical Sciences, University of Massachusetts Chan Medical School, Worcester, Massachusetts, United States of America
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6
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Zeballos C MA, Moore HJ, Smith TJ, Powell JE, Ahsan NS, Zhang S, Gaj T. Mitigating a TDP-43 proteinopathy by targeting ataxin-2 using RNA-targeting CRISPR effector proteins. Nat Commun 2023; 14:6492. [PMID: 37838698 PMCID: PMC10576788 DOI: 10.1038/s41467-023-42147-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2023] [Accepted: 10/02/2023] [Indexed: 10/16/2023] Open
Abstract
The TDP-43 proteinopathies, which include amyotrophic lateral sclerosis and frontotemporal dementia, are a devastating group of neurodegenerative disorders that are characterized by the mislocalization and aggregation of TDP-43. Here we demonstrate that RNA-targeting CRISPR effector proteins, a programmable class of gene silencing agents that includes the Cas13 family of enzymes and Cas7-11, can be used to mitigate TDP-43 pathology when programmed to target ataxin-2, a modifier of TDP-43-associated toxicity. In addition to inhibiting the aggregation and transit of TDP-43 to stress granules, we find that the in vivo delivery of an ataxin-2-targeting Cas13 system to a mouse model of TDP-43 proteinopathy improved functional deficits, extended survival, and reduced the severity of neuropathological hallmarks. Further, we benchmark RNA-targeting CRISPR platforms against ataxin-2 and find that high-fidelity forms of Cas13 possess improved transcriptome-wide specificity compared to Cas7-11 and a first-generation effector. Our results demonstrate the potential of CRISPR technology for TDP-43 proteinopathies.
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Affiliation(s)
- M Alejandra Zeballos C
- Department of Bioengineering, University of Illinois Urbana-Champaign, Urbana, IL, 61801, USA
| | - Hayden J Moore
- Department of Bioengineering, University of Illinois Urbana-Champaign, Urbana, IL, 61801, USA
| | - Tyler J Smith
- Department of Bioengineering, University of Illinois Urbana-Champaign, Urbana, IL, 61801, USA
| | - Jackson E Powell
- Department of Bioengineering, University of Illinois Urbana-Champaign, Urbana, IL, 61801, USA
| | - Najah S Ahsan
- Department of Bioengineering, University of Illinois Urbana-Champaign, Urbana, IL, 61801, USA
| | - Sijia Zhang
- Department of Bioengineering, University of Illinois Urbana-Champaign, Urbana, IL, 61801, USA
| | - Thomas Gaj
- Department of Bioengineering, University of Illinois Urbana-Champaign, Urbana, IL, 61801, USA.
- Carl R. Woese Institute for Genomic Biology, University of Illinois Urbana-Champaign, Urbana, IL, 61801, USA.
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7
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Boeynaems S, Dorone Y, Zhuang Y, Shabardina V, Huang G, Marian A, Kim G, Sanyal A, Şen NE, Griffith D, Docampo R, Lasker K, Ruiz-Trillo I, Auburger G, Holehouse AS, Kabashi E, Lin Y, Gitler AD. Poly(A)-binding protein is an ataxin-2 chaperone that regulates biomolecular condensates. Mol Cell 2023; 83:2020-2034.e6. [PMID: 37295429 PMCID: PMC10318123 DOI: 10.1016/j.molcel.2023.05.025] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2021] [Revised: 03/14/2023] [Accepted: 05/17/2023] [Indexed: 06/12/2023]
Abstract
Biomolecular condensation underlies the biogenesis of an expanding array of membraneless assemblies, including stress granules (SGs), which form under a variety of cellular stresses. Advances have been made in understanding the molecular grammar of a few scaffold proteins that make up these phases, but how the partitioning of hundreds of SG proteins is regulated remains largely unresolved. While investigating the rules that govern the condensation of ataxin-2, an SG protein implicated in neurodegenerative disease, we unexpectedly identified a short 14 aa sequence that acts as a condensation switch and is conserved across the eukaryote lineage. We identify poly(A)-binding proteins as unconventional RNA-dependent chaperones that control this regulatory switch. Our results uncover a hierarchy of cis and trans interactions that fine-tune ataxin-2 condensation and reveal an unexpected molecular function for ancient poly(A)-binding proteins as regulators of biomolecular condensate proteins. These findings may inspire approaches to therapeutically target aberrant phases in disease.
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Affiliation(s)
- Steven Boeynaems
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA; Jan and Dan Duncan Neurological Research Institute, Texas Children's Hospital, Houston, TX 77030, USA; Therapeutic Innovation Center (THINC), Baylor College of Medicine, Houston, TX 77030, USA; Center for Alzheimer's and Neurodegenerative Diseases (CAND), Texas Children's Hospital, Houston, TX 77030, USA; Dan L Duncan Comprehensive Cancer Center (DLDCCC), Baylor College of Medicine, Houston, TX 77030, USA; Department of Genetics, Stanford University, Stanford, CA 94305, USA.
| | - Yanniv Dorone
- Department of Plant Biology, Carnegie Institution for Science, Stanford, CA 94305, USA; Department of Biology, Stanford University, Stanford, CA 94305, USA
| | - Yanrong Zhuang
- IDG/McGovern Institute for Brain Research, Tsinghua-Peking Joint Centre for Life Sciences, School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Victoria Shabardina
- Institut de Biologia Evolutiva (CSIC-Universitat Pompeu Fabra), Passeig Marítim de la Barceloneta 37-49, Barcelona 08003 Catalonia, Spain
| | - Guozhong Huang
- Department of Cellular Biology and Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, GA 30602, USA
| | - Anca Marian
- Imagine Institute, Institut National de la Santé et de la Recherche Médicale (INSERM) Unité 1163, Paris Descartes Université, 75015 Paris, France
| | - Garam Kim
- Department of Genetics, Stanford University, Stanford, CA 94305, USA
| | - Anushka Sanyal
- Department of Genetics, Stanford University, Stanford, CA 94305, USA
| | - Nesli-Ece Şen
- Experimental Neurology, Goethe-University Hospital, 60590 Frankfurt, Germany
| | - Daniel Griffith
- Department of Biochemistry and Molecular Biophysics, Washington University School of Medicine, St. Louis, MO 63110, USA; Center for Biomolecular Condensates, Washington University in St Louis, St. Louis, MO 63130, USA
| | - Roberto Docampo
- Department of Cellular Biology and Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, GA 30602, USA
| | - Keren Lasker
- The Scripps Research Institute, La Jolla, CA 92037, USA
| | - Iñaki Ruiz-Trillo
- Institut de Biologia Evolutiva (CSIC-Universitat Pompeu Fabra), Passeig Marítim de la Barceloneta 37-49, Barcelona 08003 Catalonia, Spain; ICREA, Passeig Lluís Companys 23, Barcelona 08010 Catalonia, Spain
| | - Georg Auburger
- Experimental Neurology, Goethe-University Hospital, 60590 Frankfurt, Germany
| | - Alex S Holehouse
- Department of Biochemistry and Molecular Biophysics, Washington University School of Medicine, St. Louis, MO 63110, USA; Center for Biomolecular Condensates, Washington University in St Louis, St. Louis, MO 63130, USA
| | - Edor Kabashi
- Imagine Institute, Institut National de la Santé et de la Recherche Médicale (INSERM) Unité 1163, Paris Descartes Université, 75015 Paris, France
| | - Yi Lin
- IDG/McGovern Institute for Brain Research, Tsinghua-Peking Joint Centre for Life Sciences, School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Aaron D Gitler
- Department of Genetics, Stanford University, Stanford, CA 94305, USA; Chan Zuckerberg Biohub, San Francisco, CA 94158, USA.
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8
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Kim G, Nakayama L, Blum JA, Akiyama T, Boeynaems S, Chakraborty M, Couthouis J, Tassoni-Tsuchida E, Rodriguez CM, Bassik MC, Gitler AD. Genome-wide CRISPR screen reveals v-ATPase as a drug target to lower levels of ALS protein ataxin-2. Cell Rep 2022; 41:111508. [PMID: 36288714 PMCID: PMC9664452 DOI: 10.1016/j.celrep.2022.111508] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2021] [Revised: 05/20/2022] [Accepted: 09/22/2022] [Indexed: 01/27/2023] Open
Abstract
Mutations in the ataxin-2 gene (ATXN2) cause the neurodegenerative disorders amyotrophic lateral sclerosis (ALS) and spinocerebellar ataxia type 2 (SCA2). A therapeutic strategy using antisense oligonucleotides targeting ATXN2 has entered clinical trial in humans. Additional ways to decrease ataxin-2 levels could lead to cheaper or less invasive therapies and elucidate how ataxin-2 is normally regulated. Here, we perform a genome-wide fluorescence-activated cell sorting (FACS)-based CRISPR-Cas9 screen in human cells and identify genes encoding components of the lysosomal vacuolar ATPase (v-ATPase) as modifiers of endogenous ataxin-2 protein levels. Multiple FDA-approved small molecule v-ATPase inhibitors lower ataxin-2 protein levels in mouse and human neurons, and oral administration of at least one of these drugs-etidronate-is sufficient to decrease ataxin-2 in the brains of mice. Together, we propose v-ATPase as a drug target for ALS and SCA2 and demonstrate the value of FACS-based screens in identifying genetic-and potentially druggable-modifiers of human disease proteins.
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Affiliation(s)
- Garam Kim
- Department of Genetics, Stanford University School of Medicine, Stanford, CA 94305, USA; Stanford Neurosciences Interdepartmental Program, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Lisa Nakayama
- Department of Genetics, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Jacob A Blum
- Department of Genetics, Stanford University School of Medicine, Stanford, CA 94305, USA; Stanford Neurosciences Interdepartmental Program, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Tetsuya Akiyama
- Department of Genetics, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Steven Boeynaems
- Department of Genetics, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Meenakshi Chakraborty
- Department of Genetics, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Julien Couthouis
- Department of Genetics, Stanford University School of Medicine, Stanford, CA 94305, USA
| | | | - Caitlin M Rodriguez
- Department of Genetics, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Michael C Bassik
- Department of Genetics, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Aaron D Gitler
- Department of Genetics, Stanford University School of Medicine, Stanford, CA 94305, USA.
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9
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Rodriguez CM, Bechek SC, Jones GL, Nakayama L, Akiyama T, Kim G, Solow-Cordero DE, Strittmatter SM, Gitler AD. Targeting RTN4/NoGo-Receptor reduces levels of ALS protein ataxin-2. Cell Rep 2022; 41:111505. [PMID: 36288715 PMCID: PMC9664481 DOI: 10.1016/j.celrep.2022.111505] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2021] [Revised: 05/30/2022] [Accepted: 09/22/2022] [Indexed: 01/27/2023] Open
Abstract
Gene-based therapeutic strategies to lower ataxin-2 levels are emerging for the neurodegenerative diseases amyotrophic lateral sclerosis (ALS) and spinocerebellar ataxia type 2 (SCA2). Additional strategies to lower levels of ataxin-2 could be beneficial. Here, we perform a genome-wide arrayed small interfering RNA (siRNA) screen in human cells and identify RTN4R, the gene encoding the RTN4/NoGo-Receptor, as a potent modifier of ataxin-2 levels. RTN4R knockdown, or treatment with a peptide inhibitor, is sufficient to lower ataxin-2 protein levels in mouse and human neurons in vitro, and Rtn4r knockout mice have reduced ataxin-2 levels in vivo. We provide evidence that ataxin-2 shares a role with the RTN4/NoGo-Receptor in limiting axonal regeneration. Reduction of either protein increases axonal regrowth following axotomy. These data define the RTN4/NoGo-Receptor as a novel therapeutic target for ALS and SCA2 and implicate the targeting of ataxin-2 as a potential treatment following nerve injury.
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Affiliation(s)
- Caitlin M Rodriguez
- Department of Genetics, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Sophia C Bechek
- Department of Genetics, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Graham L Jones
- Department of Neurosurgery, Stanford University School of Medicine, Stanford, CA, USA
| | - Lisa Nakayama
- Department of Genetics, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Tetsuya Akiyama
- Department of Genetics, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Garam Kim
- Department of Genetics, Stanford University School of Medicine, Stanford, CA 94305, USA; Stanford Neurosciences Interdepartmental Program, Stanford University School of Medicine, Stanford, CA, USA
| | - David E Solow-Cordero
- High-Throughput Bioscience Center, Department of Chemical and Systems Biology, Stanford University, Stanford, CA, USA
| | - Stephen M Strittmatter
- Program in Cellular Neuroscience, Neurodegeneration and Repair, Yale University School of Medicine, New Haven, CT, USA
| | - Aaron D Gitler
- Department of Genetics, Stanford University School of Medicine, Stanford, CA 94305, USA.
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10
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Scoles DR, Gandelman M, Paul S, Dexheimer T, Dansithong W, Figueroa KP, Pflieger LT, Redlin S, Kales SC, Sun H, Maloney D, Damoiseaux R, Henderson MJ, Simeonov A, Jadhav A, Pulst SM. A quantitative high-throughput screen identifies compounds that lower expression of the SCA2-and ALS-associated gene ATXN2. J Biol Chem 2022; 298:102228. [PMID: 35787375 PMCID: PMC9356275 DOI: 10.1016/j.jbc.2022.102228] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2022] [Revised: 06/26/2022] [Accepted: 06/28/2022] [Indexed: 11/29/2022] Open
Abstract
CAG repeat expansions in the ATXN2 (ataxin-2) gene can cause the autosomal dominant disorder spinocerebellar ataxia type 2 (SCA2) as well as increase the risk of ALS. Abnormal molecular, motor, and neurophysiological phenotypes in SCA2 mouse models are normalized by lowering ATXN2 transcription, and reduction of nonmutant Atxn2 expression has been shown to increase the life span of mice overexpressing the TDP-43 (transactive response DNA-binding protein 43 kDa) ALS protein, demonstrating the potential benefits of targeting ATXN2 transcription in humans. Here, we describe a quantitative high-throughput screen to identify compounds that lower ATXN2 transcription. We screened 428,759 compounds in a multiplexed assay using an ATXN2-luciferase reporter in human embryonic kidney 293 (HEK-293) cells and identified a diverse set of compounds capable of lowering ATXN2 transcription. We observed dose-dependent reductions of endogenous ATXN2 in HEK-293 cells treated with procillaridin A, 17-dimethylaminoethylamino-17-demethoxygeldanamycin (17-DMAG), and heat shock protein 990 (HSP990), known inhibitors of HSP90 and Na+/K+-ATPases. Furthermore, HEK-293 cells expressing polyglutamine-expanded ATXN2-Q58 treated with 17-DMAG had minimally detectable ATXN2, as well as normalized markers of autophagy and endoplasmic reticulum stress, including STAU1 (Staufen 1), molecular target of rapamycin, p62, LC3-II (microtubule-associated protein 1A/1B-light chain 3II), CHOP (C/EBP homologous protein), and phospho-eIF2α (eukaryotic initiation factor 2α). Finally, bacterial artificial chromosome ATXN2-Q22 mice treated with 17-DMAG or HSP990 exhibited highly reduced ATXN2 protein abundance in the cerebellum. Taken together, our study demonstrates inhibition of HSP90 or Na+/K+-ATPases as potentially effective therapeutic strategies for treating SCA2 and ALS.
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Affiliation(s)
- Daniel R Scoles
- Department of Neurology, University of Utah, Salt Lake City, Utah, USA.
| | - Mandi Gandelman
- Department of Neurology, University of Utah, Salt Lake City, Utah, USA
| | - Sharan Paul
- Department of Neurology, University of Utah, Salt Lake City, Utah, USA
| | - Thomas Dexheimer
- Division of Preclinical Innovation, National Center for Advancing Translational Sciences (NCATS), Rockville, Maryland, USA
| | | | - Karla P Figueroa
- Department of Neurology, University of Utah, Salt Lake City, Utah, USA
| | - Lance T Pflieger
- Department of Biomedical Informatics, University of Utah, Salt Lake City, Utah, USA
| | - Scott Redlin
- Department of Neurology, University of Utah, Salt Lake City, Utah, USA
| | - Stephen C Kales
- Division of Preclinical Innovation, National Center for Advancing Translational Sciences (NCATS), Rockville, Maryland, USA
| | - Hongmao Sun
- Division of Preclinical Innovation, National Center for Advancing Translational Sciences (NCATS), Rockville, Maryland, USA
| | - David Maloney
- Division of Preclinical Innovation, National Center for Advancing Translational Sciences (NCATS), Rockville, Maryland, USA
| | - Robert Damoiseaux
- Department of Molecular and Medical Pharmacology, Jonsson Comprehensive Cancer Center, California NanoSystems Institute, and Department of Bioengineering in the Samueli School of Engineering, University of California Los Angeles, Los Angeles, California, USA
| | - Mark J Henderson
- Division of Preclinical Innovation, National Center for Advancing Translational Sciences (NCATS), Rockville, Maryland, USA
| | - Anton Simeonov
- Division of Preclinical Innovation, National Center for Advancing Translational Sciences (NCATS), Rockville, Maryland, USA
| | - Ajit Jadhav
- Division of Preclinical Innovation, National Center for Advancing Translational Sciences (NCATS), Rockville, Maryland, USA
| | - Stefan M Pulst
- Department of Neurology, University of Utah, Salt Lake City, Utah, USA.
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11
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Dávalos-Rodríguez NO, Rincón-Sánchez AR, Madrigal Ruiz PM, Flores-Alvarado LJ, López-Toledo S, Villafán-Bernal JR, Castro-Juárez CJ, Guzmán-López R, Siliceo-Murrieta JI, Ramirez-Garcia SA. VNTR (CAG)n polymorphism of the ATXN2 gene and metabolic parameters of cardiovascular risk associated with the degree of obesity in the Amerindian population of Oaxaca. ENDOCRINOL DIAB NUTR 2022; 69:15-24. [PMID: 35232555 DOI: 10.1016/j.endien.2021.04.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/01/2020] [Accepted: 04/13/2021] [Indexed: 06/14/2023]
Abstract
INTRODUCTION The ATXN2 gene has a VNTR (CAG)n with locus in exon1. Long alleles within the normal range (22-29 repeats) are associated with severe obesity in people from the United Kingdom, Indonesia and the Caribbean. OBJECTIVE To analyse the influence of VNTR (CAG)n on metabolic profile in adults with obesity and pre-obesity, as well as to estimate its effect on the risk of developing diabetes. METHODS AND MATERIAL 255 adults of Chinantec Amerindian ethnic origin were included, who underwent anthropometric and biochemical evaluation. The VNTR was amplified by end-point PCR and by 8% PAGE electrophoresis. RESULTS Differences were found in the waist/hip circumference index and body mass index in the carriers of genotypes different to the one homozygous for 22 repeats with a Student's t-test value of 0.0041 and 0.0334, respectively. We also found an association with a family history of chronic disease. CONCLUSION The VNTR of ATXN2 is associated with obesity in Mexican adults of Chinantec ancestry.
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Affiliation(s)
- Nory O Dávalos-Rodríguez
- Instituto de Genética Humana Dr. Enrique Corona Rivera, Departamento de Biología Molecular y Genómica, Centro Universitario de Ciencias de la Salud, Universidad de Guadalajara, Guadalajara, Jalisco, Mexico
| | - Ana Rosa Rincón-Sánchez
- IBMMTG, Departamento de Biología Molecular y Genómica, Centro Universitario de Ciencias de la Salud (CUCS), Universidad de Guadalajara, Guadalajara, Jalisco, Mexico
| | - Perla Montserrat Madrigal Ruiz
- IBMMTG, Departamento de Biología Molecular y Genómica, Centro Universitario de Ciencias de la Salud (CUCS), Universidad de Guadalajara, Guadalajara, Jalisco, Mexico
| | - Luis Javier Flores-Alvarado
- IBMMTG, Departamento de Biología Molecular y Genómica, Centro Universitario de Ciencias de la Salud (CUCS), Universidad de Guadalajara, Guadalajara, Jalisco, Mexico
| | | | | | | | | | | | - Sergio Alberto Ramirez-Garcia
- Instituto de Nutrición, Universidad de la Sierra Sur, Oaxaca, Mexico; Maestría en Salud Pública, División de Estudios de Posgrado, Universidad de la Sierra Sur, Oaxaca, Mexico.
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12
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McGurk L, Rifai OM, Shcherbakova O, Perlegos AE, Byrns CN, Carranza FR, Zhou HW, Kim HJ, Zhu Y, Bonini NM. Toxicity of pathogenic ataxin-2 in Drosophila shows dependence on a pure CAG repeat sequence. Hum Mol Genet 2021; 30:1797-1810. [PMID: 34077532 PMCID: PMC8444453 DOI: 10.1093/hmg/ddab148] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2021] [Revised: 05/12/2021] [Accepted: 05/24/2021] [Indexed: 12/31/2022] Open
Abstract
Spinocerebellar ataxia type 2 is a polyglutamine (polyQ) disease associated with an expanded polyQ domain within the protein product of the ATXN2 gene. Interestingly, polyQ repeat expansions in ATXN2 are also associated with amyotrophic lateral sclerosis (ALS) and parkinsonism depending upon the length of the polyQ repeat expansion. The sequence encoding the polyQ repeat also varies with disease presentation: a pure CAG repeat is associated with SCA2, whereas the CAG repeat in ALS and parkinsonism is typically interrupted with the glutamine encoding CAA codon. Here, we asked if the purity of the CAG sequence encoding the polyQ repeat in ATXN2 could impact the toxicity of the ataxin-2 protein in vivo in Drosophila. We found that ataxin-2 encoded by a pure CAG repeat conferred toxicity in the retina and nervous system, whereas ataxin-2 encoded by a CAA-interrupted repeat or CAA-only repeat failed to confer toxicity, despite expression of the protein at similar levels. Furthermore, the CAG-encoded ataxin-2 protein aggregated in the fly eye, while ataxin-2 encoded by either a CAA/G or CAA repeat remained diffuse. The toxicity of the CAG-encoded ataxin-2 protein was also sensitive to the translation factor eIF4H, a known modifier of the toxic GGGGCC repeat in flies. These data indicate that ataxin-2 encoded by a pure CAG versus interrupted CAA/G polyQ repeat domain is associated with differential toxicity, indicating that mechanisms associated with the purity of the sequence of the polyQ domain contribute to disease.
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Affiliation(s)
- Leeanne McGurk
- Division of Cell & Developmental Biology, School of Life Sciences, University of Dundee, Dundee, UK
- Department of Biology, University of Pennsylvania, Philadelphia, PA, USA
| | - Olivia M Rifai
- Department of Biology, University of Pennsylvania, Philadelphia, PA, USA
| | | | | | - China N Byrns
- Neurosciences Graduate Group, University of Pennsylvania, Philadelphia, PA, USA
- Medical Sciences Training Program, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Faith R Carranza
- Department of Biology, University of Pennsylvania, Philadelphia, PA, USA
| | - Henry W Zhou
- Department of Biology, University of Pennsylvania, Philadelphia, PA, USA
| | - Hyung-Jun Kim
- Department of Biology, University of Pennsylvania, Philadelphia, PA, USA
| | - Yongqing Zhu
- Department of Biology, University of Pennsylvania, Philadelphia, PA, USA
| | - Nancy M Bonini
- Department of Biology, University of Pennsylvania, Philadelphia, PA, USA
- Neurosciences Graduate Group, University of Pennsylvania, Philadelphia, PA, USA
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13
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Liguori F, Amadio S, Volonté C. Fly for ALS: Drosophila modeling on the route to amyotrophic lateral sclerosis modifiers. Cell Mol Life Sci 2021; 78:6143-6160. [PMID: 34322715 PMCID: PMC11072332 DOI: 10.1007/s00018-021-03905-8] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2021] [Revised: 07/20/2021] [Accepted: 07/22/2021] [Indexed: 12/11/2022]
Abstract
Amyotrophic lateral sclerosis (ALS) is a rare, devastating disease, causing movement impairment, respiratory failure and ultimate death. A plethora of genetic, cellular and molecular mechanisms are involved in ALS signature, although the initiating causes and progressive pathological events are far from being understood. Drosophila research has produced seminal discoveries for more than a century and has been successfully used in the past 25 years to untangle the process of ALS pathogenesis, and recognize potential markers and novel strategies for therapeutic solutions. This review will provide an updated view of several ALS modifiers validated in C9ORF72, SOD1, FUS, TDP-43 and Ataxin-2 Drosophila models. We will discuss basic and preclinical findings, illustrating recent developments and novel breakthroughs, also depicting unsettled challenges and limitations in the Drosophila-ALS field. We intend to stimulate a renewed debate on Drosophila as a screening route to identify more successful disease modifiers and neuroprotective agents.
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Affiliation(s)
- Francesco Liguori
- Preclinical Neuroscience, IRCCS Fondazione Santa Lucia, Via del Fosso di Fiorano 65, 00143, Rome, Italy
| | - Susanna Amadio
- Preclinical Neuroscience, IRCCS Fondazione Santa Lucia, Via del Fosso di Fiorano 65, 00143, Rome, Italy
| | - Cinzia Volonté
- Preclinical Neuroscience, IRCCS Fondazione Santa Lucia, Via del Fosso di Fiorano 65, 00143, Rome, Italy.
- Institute for Systems Analysis and Computer Science "A. Ruberti", National Research Council (IASI-CNR), Via dei Taurini 19, 00185, Rome, Italy.
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14
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Abstract
PURPOSE OF REVIEW To provide an update on the role of Ataxin-2 gene (ATXN2) in health and neurological diseases. RECENT FINDINGS There is a growing complexity emerging on the role of ATXN2 and its variants in association with SCA2 and several other neurological diseases. Polymorphisms and intermediate alleles in ATXN2 establish this gene as a powerful modulator of neurological diseases including lethal neurodegenerative conditions such as motor neuron disease, spinocerebellar ataxia 3 (SCA3), and peripheral nerve disease such as familial amyloidosis polyneuropathy. This role is in fact far wider than the previously described for polymorphism in the prion protein (PRNP) gene. Positive data from antisense oligo therapy in a murine model of SCA2 suggest that similar approaches may be feasible in humans SCA2 patients. SUMMARY ATXN2 is one of the few genes where a single gene causes several diseases and/or modifies several and disparate neurological disorders. Hence, understanding mutagenesis, genetic variants, and biological functions will help managing SCA2, and several human diseases connected with dysfunctional pathways in the brain, innate immunity, autophagy, cellular, lipid, and RNA metabolism.
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Affiliation(s)
- Jose Miguel Laffita-Mesa
- Department of Clinical Neuroscience (CNS), J5:20 Bioclinicum, Karolinska University Hospital, Stockholm, Sweden
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15
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Cerqueira JXM, Saavalainen P, Kurppa K, Laurikka P, Huhtala H, Nykter M, L E Koskinen L, Yohannes DA, Kilpeläinen E, Shcherban A, Palotie A, Kaukinen K, Lindfors K. Independent and cumulative coeliac disease-susceptibility loci are associated with distinct disease phenotypes. J Hum Genet 2021; 66:613-623. [PMID: 33446885 PMCID: PMC8144013 DOI: 10.1038/s10038-020-00888-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2020] [Revised: 12/01/2020] [Accepted: 12/01/2020] [Indexed: 12/12/2022]
Abstract
The phenotype of coeliac disease varies considerably for incompletely understood reasons. We investigated whether established coeliac disease susceptibility variants (SNPs) are individually or cumulatively associated with distinct phenotypes. We also tested whether a polygenic risk score (PRS) based on genome-wide associated (GWA) data could explain the phenotypic variation. The phenotypic association of 39 non-HLA coeliac disease SNPs was tested in 625 thoroughly phenotyped coeliac disease patients and 1817 controls. To assess their cumulative effects a weighted genetic risk score (wGRS39) was built, and stratified by tertiles. In our PRS model in cases, we took the summary statistics from the largest GWA study in coeliac disease and tested their association at eight P value thresholds (PT) with phenotypes. Altogether ten SNPs were associated with distinct phenotypes after correction for multiple testing (PEMP2 ≤ 0.05). The TLR7/TLR8 locus was associated with disease onset before and the SH2B3/ATXN2, ITGA4/UBE2E3 and IL2/IL21 loci after 7 years of age. The latter three loci were associated with a more severe small bowel mucosal damage and SH2B3/ATXN2 with type 1 diabetes. Patients at the highest wGRS39 tertiles had OR > 1.62 for having coeliac disease-related symptoms during childhood, a more severe small bowel mucosal damage, malabsorption and anaemia. PRS was associated only with dermatitis herpetiformis (PT = 0.2, PEMP2 = 0.02). Independent coeliac disease-susceptibility loci are associated with distinct phenotypes, suggesting that genetic factors play a role in determining the disease presentation. Moreover, the increased number of coeliac disease susceptibility SNPs might predispose to a more severe disease course.
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Affiliation(s)
- Juliana X M Cerqueira
- Coeliac Disease Research Center, Faculty of Medicine and Health Technology, Tampere University, Tampere, Finland
| | - Päivi Saavalainen
- Research Programs Unit, Immunobiology, and the Haartman Institute, Department of Molecular Genetics, University of Helsinki, Helsinki, Finland
| | - Kalle Kurppa
- Center for Child Health Research, Tampere University and Tampere University Hospital, Tampere, and the University Consortium of Seinäjoki, Seinäjoki, Finland
| | - Pilvi Laurikka
- Coeliac Disease Research Center, Faculty of Medicine and Health Technology, Tampere University, Tampere, Finland
| | - Heini Huhtala
- Faculty of Social Sciences, Tampere University, Tampere, Finland
| | - Matti Nykter
- Laboratory of Computational Biology, Faculty of Medicine and Health Technology, Tampere University, Tampere, Finland
| | - Lotta L E Koskinen
- Research Programs Unit, Immunobiology, and the Haartman Institute, Department of Molecular Genetics, University of Helsinki, Helsinki, Finland
| | - Dawit A Yohannes
- Research Programs Unit, Immunobiology, and the Haartman Institute, Department of Molecular Genetics, University of Helsinki, Helsinki, Finland
| | - Elina Kilpeläinen
- Institute for Molecular Medicine Finland (FIMM), University of Helsinki, Helsinki, Finland
| | - Anastasia Shcherban
- Institute for Molecular Medicine Finland (FIMM), University of Helsinki, Helsinki, Finland
| | - Aarno Palotie
- Institute for Molecular Medicine Finland (FIMM), University of Helsinki, Helsinki, Finland
- Broad Institute of the Massachusetts Institute of Technology and Harvard University, Cambridge, MA, USA
- Psychiatric & Neurodevelopmental Genetics Unit, Department of Psychiatry, Analytic and Translational Genetics Unit, Department of Medicine, and the Department of Neurology, Massachusetts General Hospital, Boston, MA, USA
| | - Katri Kaukinen
- Coeliac Disease Research Center, Faculty of Medicine and Health Technology, Tampere University, Tampere, Finland
- Department of Internal Medicine, Tampere University Hospital, Tampere, Finland
| | - Katri Lindfors
- Coeliac Disease Research Center, Faculty of Medicine and Health Technology, Tampere University, Tampere, Finland.
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16
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Rodríguez-Labrada R, Martins AC, Magaña JJ, Vazquez-Mojena Y, Medrano-Montero J, Fernandez-Ruíz J, Cisneros B, Teive H, McFarland KN, Saraiva-Pereira ML, Cerecedo-Zapata CM, Gomez CM, Ashizawa T, Velázquez-Pérez L, Jardim LB. Founder Effects of Spinocerebellar Ataxias in the American Continents and the Caribbean. Cerebellum 2021; 19:446-458. [PMID: 32086717 DOI: 10.1007/s12311-020-01109-7] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Spinocerebellar ataxias (SCAs) comprise a heterogeneous group of autosomal dominant disorders. The relative frequency of the different SCA subtypes varies broadly among different geographical and ethnic groups as result of genetic drifts. This review aims to provide an update regarding SCA founders in the American continents and the Caribbean as well as to discuss characteristics of these populations. Clusters of SCAs were detected in Eastern regions of Cuba for SCA2, in South Brazil for SCA3/MJD, and in Southeast regions of Mexico for SCA7. Prevalence rates were obtained and reached 154 (municipality of Báguano, Cuba), 166 (General Câmara, Brazil), and 423 (Tlaltetela, Mexico) patients/100,000 for SCA2, SCA3/MJD, and SCA7, respectively. In contrast, the scattered families with spinocerebellar ataxia type 10 (SCA10) reported all over North and South Americas have been associated to a common Native American ancestry that may have risen in East Asia and migrated to Americas 10,000 to 20,000 years ago. The comprehensive review showed that for each of these SCAs corresponded at least the development of one study group with a large production of scientific evidence often generalizable to all carriers of these conditions. Clusters of SCA populations in the American continents and the Caribbean provide unusual opportunity to gain insights into clinical and genetic characteristics of these disorders. Furthermore, the presence of large populations of patients living close to study centers can favor the development of meaningful clinical trials, which will impact on therapies and on quality of life of SCA carriers worldwide.
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Affiliation(s)
| | - Ana Carolina Martins
- Programa de Pós-Graduação em Genética e Biologia Molecular, Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, RS, 91540-070, Brazil
| | - Jonathan J Magaña
- Department of Genetics, Laboratory of Genomic Medicine, National Rehabilitation Institute (INR-LGII), 14389, Mexico City, Mexico
| | - Yaimeé Vazquez-Mojena
- Centre for the Research and Rehabilitation of Hereditary Ataxias, 80100, Holguín, Cuba
| | | | - Juan Fernandez-Ruíz
- Departamento de Fisiología, Facultad de Medicina, Universidad Nacional Autonoma de Mexico, 04510, Mexico City, Mexico
| | - Bulmaro Cisneros
- Department of Genetics and Molecular Biology, Center of Research and Advanced Studies (CINVESTAV-IPN), 07360, Mexico City, Mexico
| | - Helio Teive
- Movement Disorders Unit, Neurology Service, Internal Medicine Department, Hospital de Clínicas Federal University of Paraná, Curitiba, PR, 80240-440, Brazil
| | | | - Maria Luiza Saraiva-Pereira
- Programa de Pós-Graduação em Genética e Biologia Molecular, Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, RS, 91540-070, Brazil
- Hospital de Clínicas de Porto Alegre (HCPA), Porto Alegre, RS, 90035-903, Brazil
- Departamento de Bioquímica, Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, RS, 90035-903, Brazil
| | - César M Cerecedo-Zapata
- Department of Genetics, Laboratory of Genomic Medicine, National Rehabilitation Institute (INR-LGII), 14389, Mexico City, Mexico
- Rehabilitation and Social Inclusion Center of Veracruz (CRIS-DIF), Xalapa, 91070, Veracruz, Mexico
| | | | - Tetsuo Ashizawa
- Program of Neuroscience, Houston Methodist Research Institute, Houston, TX, 77030, USA
| | - Luis Velázquez-Pérez
- Centre for the Research and Rehabilitation of Hereditary Ataxias, 80100, Holguín, Cuba.
- Cuban Academy of Sciences, 10100, La Havana, Cuba.
| | - Laura Bannach Jardim
- Programa de Pós-Graduação em Genética e Biologia Molecular, Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, RS, 91540-070, Brazil
- Hospital de Clínicas de Porto Alegre (HCPA), Porto Alegre, RS, 90035-903, Brazil
- Departamento de Medicina Interna, Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, RS, 90035-903, Brazil
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17
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Singh A, Hulsmeier J, Kandi AR, Pothapragada SS, Hillebrand J, Petrauskas A, Agrawal K, RT K, Thiagarajan D, Jayaprakashappa D, VijayRaghavan K, Ramaswami M, Bakthavachalu B. Antagonistic roles for Ataxin-2 structured and disordered domains in RNP condensation. eLife 2021; 10:e60326. [PMID: 33689682 PMCID: PMC7946432 DOI: 10.7554/elife.60326] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2020] [Accepted: 02/23/2021] [Indexed: 02/07/2023] Open
Abstract
Ataxin-2 (Atx2) is a translational control molecule mutated in spinocerebellar ataxia type II and amyotrophic lateral sclerosis. While intrinsically disordered domains (IDRs) of Atx2 facilitate mRNP condensation into granules, how IDRs work with structured domains to enable positive and negative regulation of target mRNAs remains unclear. Using the Targets of RNA-Binding Proteins Identified by Editing technology, we identified an extensive data set of Atx2-target mRNAs in the Drosophila brain and S2 cells. Atx2 interactions with AU-rich elements in 3'UTRs appear to modulate stability/turnover of a large fraction of these target mRNAs. Further genomic and cell biological analyses of Atx2 domain deletions demonstrate that Atx2 (1) interacts closely with target mRNAs within mRNP granules, (2) contains distinct protein domains that drive or oppose RNP-granule assembly, and (3) has additional essential roles outside of mRNP granules. These findings increase the understanding of neuronal translational control mechanisms and inform strategies for Atx2-based interventions under development for neurodegenerative disease.
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Affiliation(s)
- Amanjot Singh
- National Centre for Biological SciencesBangaloreIndia
| | - Joern Hulsmeier
- Trinity College Institute of Neuroscience, School of Genetics and Microbiology, Smurfit Institute of Genetics and School of Natural Sciences, Trinity College DublinDublinIreland
| | - Arvind Reddy Kandi
- National Centre for Biological SciencesBangaloreIndia
- Tata Institute for Genetics and Society Centre at inStem, Bellary RoadBangaloreIndia
| | | | - Jens Hillebrand
- Trinity College Institute of Neuroscience, School of Genetics and Microbiology, Smurfit Institute of Genetics and School of Natural Sciences, Trinity College DublinDublinIreland
| | - Arnas Petrauskas
- Trinity College Institute of Neuroscience, School of Genetics and Microbiology, Smurfit Institute of Genetics and School of Natural Sciences, Trinity College DublinDublinIreland
| | - Khushboo Agrawal
- Tata Institute for Genetics and Society Centre at inStem, Bellary RoadBangaloreIndia
- School of Biotechnology, Amrita Vishwa Vidyapeetham UniversityKollamIndia
| | - Krishnan RT
- National Centre for Biological SciencesBangaloreIndia
| | | | | | | | - Mani Ramaswami
- National Centre for Biological SciencesBangaloreIndia
- Trinity College Institute of Neuroscience, School of Genetics and Microbiology, Smurfit Institute of Genetics and School of Natural Sciences, Trinity College DublinDublinIreland
| | - Baskar Bakthavachalu
- National Centre for Biological SciencesBangaloreIndia
- Tata Institute for Genetics and Society Centre at inStem, Bellary RoadBangaloreIndia
- School of Basic Sciences, Indian Institute of TechnologyMandiIndia
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18
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Cha IJ, Lee D, Park SS, Chung CG, Kim SY, Jo MG, Kim SY, Lee BH, Lee YS, Lee SB. Ataxin-2 Dysregulation Triggers a Compensatory Fragile X Mental Retardation Protein Decrease in Drosophila C4da Neurons. Mol Cells 2020; 43:870-879. [PMID: 33115979 PMCID: PMC7604024 DOI: 10.14348/molcells.2020.0158] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2020] [Revised: 09/24/2020] [Accepted: 09/24/2020] [Indexed: 12/19/2022] Open
Abstract
Dendrites require precise and timely delivery of protein substrates to distal areas to ensure the correct morphology and function of neurons. Many of these protein substrates are supplied in the form of ribonucleoprotein (RNP) complex consisting of RNA-binding proteins (RBPs) and mRNAs, which are subsequently translated in distal dendritic areas. It remains elusive, however, whether key RBPs supply mRNA according to local demands individually or in a coordinated manner. In this study, we investigated how Drosophila sensory neurons respond to the dysregulation of a disease-associated RBP, Ataxin-2 (ATX2), which leads to dendritic defects. We found that ATX2 plays a crucial role in spacing dendritic branches for the optimal dendritic receptive fields in Drosophila class IV dendritic arborization (C4da) neurons, where both expression level and subcellular location of ATX2 contribute significantly to this effect. We showed that translational upregulation through the expression of eukaryotic translation initiation factor 4E (eIF4E) further enhanced the ATX2-induced dendritic phenotypes. Additionally, we found that the expression level of another disease-associated RBP, fragile X mental retardation protein (FMRP), decreased in both cell bodies and dendrites when neurons were faced with aberrant upregulation of ATX2. Finally, we revealed that the PAM2 motif of ATX2, which mediates its interaction with poly(A)-binding protein (PABP), is potentially necessary for the decrease of FMRP in certain neuronal stress conditions. Collectively, our data suggest that dysregulation of RBPs triggers a compensatory regulation of other functionally-overlapping RBPs to minimize RBP dysregulation-associated aberrations that hinder neuronal homeostasis in dendrites.
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Affiliation(s)
- In Jun Cha
- Department of Brain & Cognitive Sciences, Daegu Gyeongbuk Institute of Science & Technology (DGIST), Daegu 42988, Korea
- Protein Dynamics-Based Proteotoxicity Control Laboratory, Basic Research Lab, DGIST, Daegu 42988, Korea
| | - Davin Lee
- Department of Brain & Cognitive Sciences, Daegu Gyeongbuk Institute of Science & Technology (DGIST), Daegu 42988, Korea
- Protein Dynamics-Based Proteotoxicity Control Laboratory, Basic Research Lab, DGIST, Daegu 42988, Korea
| | - Sung Soon Park
- Department of Brain & Cognitive Sciences, Daegu Gyeongbuk Institute of Science & Technology (DGIST), Daegu 42988, Korea
- Protein Dynamics-Based Proteotoxicity Control Laboratory, Basic Research Lab, DGIST, Daegu 42988, Korea
| | - Chang Geon Chung
- Department of Brain & Cognitive Sciences, Daegu Gyeongbuk Institute of Science & Technology (DGIST), Daegu 42988, Korea
- Protein Dynamics-Based Proteotoxicity Control Laboratory, Basic Research Lab, DGIST, Daegu 42988, Korea
| | - Seung Yeon Kim
- Department of Brain & Cognitive Sciences, Daegu Gyeongbuk Institute of Science & Technology (DGIST), Daegu 42988, Korea
- Protein Dynamics-Based Proteotoxicity Control Laboratory, Basic Research Lab, DGIST, Daegu 42988, Korea
| | - Min Gu Jo
- Department of Brain & Cognitive Sciences, Daegu Gyeongbuk Institute of Science & Technology (DGIST), Daegu 42988, Korea
- Protein Dynamics-Based Proteotoxicity Control Laboratory, Basic Research Lab, DGIST, Daegu 42988, Korea
| | - Seung Yeol Kim
- Department of Brain & Cognitive Sciences, Daegu Gyeongbuk Institute of Science & Technology (DGIST), Daegu 42988, Korea
- Protein Dynamics-Based Proteotoxicity Control Laboratory, Basic Research Lab, DGIST, Daegu 42988, Korea
| | - Byung-Hoon Lee
- Protein Dynamics-Based Proteotoxicity Control Laboratory, Basic Research Lab, DGIST, Daegu 42988, Korea
- Department of New Biology, DGIST, Daegu 42988, Korea
| | - Young-Sam Lee
- Protein Dynamics-Based Proteotoxicity Control Laboratory, Basic Research Lab, DGIST, Daegu 42988, Korea
- Department of New Biology, DGIST, Daegu 42988, Korea
- Well Aging Research Center, Division of Biotechnology, DGIST, Daegu 42988, Korea
| | - Sung Bae Lee
- Department of Brain & Cognitive Sciences, Daegu Gyeongbuk Institute of Science & Technology (DGIST), Daegu 42988, Korea
- Protein Dynamics-Based Proteotoxicity Control Laboratory, Basic Research Lab, DGIST, Daegu 42988, Korea
- Well Aging Research Center, Division of Biotechnology, DGIST, Daegu 42988, Korea
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Arsović A, Halbach MV, Canet-Pons J, Esen-Sehir D, Döring C, Freudenberg F, Czechowska N, Seidel K, Baader SL, Gispert S, Sen NE, Auburger G. Mouse Ataxin-2 Expansion Downregulates CamKII and Other Calcium Signaling Factors, Impairing Granule-Purkinje Neuron Synaptic Strength. Int J Mol Sci 2020; 21:E6673. [PMID: 32932600 PMCID: PMC7555182 DOI: 10.3390/ijms21186673] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2020] [Revised: 09/07/2020] [Accepted: 09/10/2020] [Indexed: 12/13/2022] Open
Abstract
Spinocerebellar ataxia type 2 (SCA2) is caused by polyglutamine expansion in Ataxin-2 (ATXN2). This factor binds RNA/proteins to modify metabolism after stress, and to control calcium (Ca2+) homeostasis after stimuli. Cerebellar ataxias and corticospinal motor neuron degeneration are determined by gain/loss in ATXN2 function, so we aimed to identify key molecules in this atrophic process, as potential disease progression markers. Our Atxn2-CAG100-Knock-In mouse faithfully models features observed in patients at pre-onset, early and terminal stages. Here, its cerebellar global RNA profiling revealed downregulation of signaling cascades to precede motor deficits. Validation work at mRNA/protein level defined alterations that were independent of constant physiological ATXN2 functions, but specific for RNA/aggregation toxicity, and progressive across the short lifespan. The earliest changes were detected at three months among Ca2+ channels/transporters (Itpr1, Ryr3, Atp2a2, Atp2a3, Trpc3), IP3 metabolism (Plcg1, Inpp5a, Itpka), and Ca2+-Calmodulin dependent kinases (Camk2a, Camk4). CaMKIV-Sam68 control over alternative splicing of Nrxn1, an adhesion component of glutamatergic synapses between granule and Purkinje neurons, was found to be affected. Systematic screening of pre/post-synapse components, with dendrite morphology assessment, suggested early impairment of CamKIIα abundance together with the weakening of parallel fiber connectivity. These data reveal molecular changes due to ATXN2 pathology, primarily impacting excitability and communication.
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Affiliation(s)
- Aleksandar Arsović
- Experimental Neurology, Medical Faculty, Goethe University, Theodor Stern Kai 7, 60590 Frankfurt am Main, Germany; (A.A.); (M.V.H.); (J.C.-P.); (S.G.)
| | - Melanie Vanessa Halbach
- Experimental Neurology, Medical Faculty, Goethe University, Theodor Stern Kai 7, 60590 Frankfurt am Main, Germany; (A.A.); (M.V.H.); (J.C.-P.); (S.G.)
| | - Júlia Canet-Pons
- Experimental Neurology, Medical Faculty, Goethe University, Theodor Stern Kai 7, 60590 Frankfurt am Main, Germany; (A.A.); (M.V.H.); (J.C.-P.); (S.G.)
| | - Dilhan Esen-Sehir
- Department of Psychiatry, Psychosomatic Medicine and Psychotherapy, Medical Faculty, Goethe University, Heinrich-Hoffmann-Str. 10, 60528 Frankfurt am Main, Germany; (D.E.-S.); (F.F.)
- Faculty of Biosciences, Goethe-University, Max von Laue Strasse 9, 60438 Frankfurt am Main, Germany
| | - Claudia Döring
- Dr. Senckenberg Institute of Pathology, Goethe University Frankfurt, Theodor Stern Kai 7, 60590 Frankfurt am Main, Germany;
| | - Florian Freudenberg
- Department of Psychiatry, Psychosomatic Medicine and Psychotherapy, Medical Faculty, Goethe University, Heinrich-Hoffmann-Str. 10, 60528 Frankfurt am Main, Germany; (D.E.-S.); (F.F.)
| | - Nicoletta Czechowska
- Institute of Anatomy, Anatomy and Cell Biology, University of Bonn, Nussallee 10, 53115 Bonn, Germany; (N.C.); (K.S.); (S.L.B.)
| | - Kay Seidel
- Institute of Anatomy, Anatomy and Cell Biology, University of Bonn, Nussallee 10, 53115 Bonn, Germany; (N.C.); (K.S.); (S.L.B.)
| | - Stephan L. Baader
- Institute of Anatomy, Anatomy and Cell Biology, University of Bonn, Nussallee 10, 53115 Bonn, Germany; (N.C.); (K.S.); (S.L.B.)
| | - Suzana Gispert
- Experimental Neurology, Medical Faculty, Goethe University, Theodor Stern Kai 7, 60590 Frankfurt am Main, Germany; (A.A.); (M.V.H.); (J.C.-P.); (S.G.)
| | - Nesli-Ece Sen
- Experimental Neurology, Medical Faculty, Goethe University, Theodor Stern Kai 7, 60590 Frankfurt am Main, Germany; (A.A.); (M.V.H.); (J.C.-P.); (S.G.)
- Faculty of Biosciences, Goethe-University, Max von Laue Strasse 9, 60438 Frankfurt am Main, Germany
| | - Georg Auburger
- Experimental Neurology, Medical Faculty, Goethe University, Theodor Stern Kai 7, 60590 Frankfurt am Main, Germany; (A.A.); (M.V.H.); (J.C.-P.); (S.G.)
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20
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Abstract
A variety of Magnetic Resonance (MR) and nuclear medicine (NM) techniques have been used in symptomatic and presymptomatic SCA2 gene carriers to explore, in vivo, the physiopathological biomarkers of the neurological dysfunctions characterizing the associated progressive disease that presents with a cerebellar syndrome, or less frequently, with a levodopa-responsive parkinsonian syndrome. Morphometry performed on T1-weighted images and diffusion MR imaging enable structural and microstructural evaluation of the brain in presymptomatic and symptomatic SCA2 gene carriers, in whom they show the typical pattern of olivopontocerebellar atrophy observed at neuropathological examination. Proton MR spectroscopy reveals, in the pons and cerebellum of SCA2 gene carriers, a more pronounced degree of abnormal neurochemical profile compared to other spinocerebellar ataxias with decreased NAA/Cr and Cho/Cr, increased mi/Cr ratios, and decreased NAA and increased mI concentrations. These neurochemical abnormalities are detectable also in presymtomatic gene carriers. Resting state functional MRI (rsfMRI) demonstrates decreased functional connectivity within the cerebellum and of the cerebellum with fronto-parietal cortices and basal ganglia in symptomatic SCA2 subjects. 18F-fluorodeoxyglucose Positron Emission Tomography (PET) shows a symmetric decrease of the glucose uptake in the cerebellar cortex, the dentate nucleus, the brainstem and the parahippocampal cortex. Single photon emission tomography and PET using several radiotracers have revealed almost symmetric nigrostriatal dopaminergic dysfunction irrespective of clinical signs of parkinsonism which are already present in presymtomatic gene carriers. Longitudinal small size studies have proven that morphometry and diffusion MR imaging can track neurodegeneration in SCA2, and hence serve as progression biomarkers. So far, such a capability has not been reported for proton MR spectroscopy, rsfMRI and NM techniques. A search for the best surrogate marker for future clinical trials represents the current challenge for the neuroimaging community.
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Affiliation(s)
- Mario Mascalchi
- Department of Clinical and Experimental Biomedical Sciences, University of Florence, 50121 Florence, Italy
- Correspondence: ; Tel.: +39-329-808-1701
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21
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Hansen M, Zeddies S, Meinders M, di Summa F, Rollmann E, van Alphen FP, Hoogendijk AJ, Moore KS, Halbach M, Gutiérrez L, van den Biggelaar M, Thijssen-Timmer DC, Auburger GW, van den Akker E, von Lindern M. The RNA-Binding Protein ATXN2 is Expressed during Megakaryopoiesis and May Control Timing of Gene Expression. Int J Mol Sci 2020; 21:ijms21030967. [PMID: 32024018 PMCID: PMC7037754 DOI: 10.3390/ijms21030967] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2019] [Revised: 01/21/2020] [Accepted: 01/30/2020] [Indexed: 12/13/2022] Open
Abstract
Megakaryopoiesis is the process during which megakaryoblasts differentiate to polyploid megakaryocytes that can subsequently shed thousands of platelets in the circulation. Megakaryocytes accumulate mRNA during their maturation, which is required for the correct spatio-temporal production of cytoskeletal proteins, membranes and platelet-specific granules, and for the subsequent shedding of thousands of platelets per cell. Gene expression profiling identified the RNA binding protein ATAXIN2 (ATXN2) as a putative novel regulator of megakaryopoiesis. ATXN2 expression is high in CD34+/CD41+ megakaryoblasts and sharply decreases upon maturation to megakaryocytes. ATXN2 associates with DDX6 suggesting that it may mediate repression of mRNA translation during early megakaryopoiesis. Comparative transcriptome and proteome analysis on megakaryoid cells (MEG-01) with differential ATXN2 expression identified ATXN2 dependent gene expression of mRNA and protein involved in processes linked to hemostasis. Mice deficient for Atxn2 did not display differences in bleeding times, but the expression of key surface receptors on platelets, such as ITGB3 (carries the CD61 antigen) and CD31 (PECAM1), was deregulated and platelet aggregation upon specific triggers was reduced.
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Affiliation(s)
- Marten Hansen
- Department Hematopoiesis, Sanquin Research, and Landsteiner Laboratory, Amsterdam University Medical Centre, 1066CX Amsterdam, The Netherlands; (M.H.); (S.Z.); (F.d.S.); (K.S.M.); (D.C.T.-T.); (E.v.d.A.)
| | - Sabrina Zeddies
- Department Hematopoiesis, Sanquin Research, and Landsteiner Laboratory, Amsterdam University Medical Centre, 1066CX Amsterdam, The Netherlands; (M.H.); (S.Z.); (F.d.S.); (K.S.M.); (D.C.T.-T.); (E.v.d.A.)
| | - Marjolein Meinders
- Department Blood Cell Research, Sanquin Research and Landsteiner Laboratory, Academic Medical Centre, University of Amsterdam,1066CX Amsterdam, The Netherlands; (M.M.); (L.G.)
| | - Franca di Summa
- Department Hematopoiesis, Sanquin Research, and Landsteiner Laboratory, Amsterdam University Medical Centre, 1066CX Amsterdam, The Netherlands; (M.H.); (S.Z.); (F.d.S.); (K.S.M.); (D.C.T.-T.); (E.v.d.A.)
| | - Ewa Rollmann
- Experimental Neurology, Goethe University Medical School, 60528 Frankfurt am Main, Germany; (E.R.); (M.H.)
| | - Floris P.J. van Alphen
- Department of Molecular and Cellular Hemostasis, Sanquin Research, 1066CX Amsterdam, The Netherlands (A.J.H.); (M.v.d.B.)
| | - Arjan J. Hoogendijk
- Department of Molecular and Cellular Hemostasis, Sanquin Research, 1066CX Amsterdam, The Netherlands (A.J.H.); (M.v.d.B.)
| | - Kat S. Moore
- Department Hematopoiesis, Sanquin Research, and Landsteiner Laboratory, Amsterdam University Medical Centre, 1066CX Amsterdam, The Netherlands; (M.H.); (S.Z.); (F.d.S.); (K.S.M.); (D.C.T.-T.); (E.v.d.A.)
| | - Melanie Halbach
- Experimental Neurology, Goethe University Medical School, 60528 Frankfurt am Main, Germany; (E.R.); (M.H.)
| | - Laura Gutiérrez
- Department Blood Cell Research, Sanquin Research and Landsteiner Laboratory, Academic Medical Centre, University of Amsterdam,1066CX Amsterdam, The Netherlands; (M.M.); (L.G.)
| | - Maartje van den Biggelaar
- Department of Molecular and Cellular Hemostasis, Sanquin Research, 1066CX Amsterdam, The Netherlands (A.J.H.); (M.v.d.B.)
| | - Daphne C. Thijssen-Timmer
- Department Hematopoiesis, Sanquin Research, and Landsteiner Laboratory, Amsterdam University Medical Centre, 1066CX Amsterdam, The Netherlands; (M.H.); (S.Z.); (F.d.S.); (K.S.M.); (D.C.T.-T.); (E.v.d.A.)
| | - Georg W.J. Auburger
- Experimental Neurology, Goethe University Medical School, 60528 Frankfurt am Main, Germany; (E.R.); (M.H.)
| | - Emile van den Akker
- Department Hematopoiesis, Sanquin Research, and Landsteiner Laboratory, Amsterdam University Medical Centre, 1066CX Amsterdam, The Netherlands; (M.H.); (S.Z.); (F.d.S.); (K.S.M.); (D.C.T.-T.); (E.v.d.A.)
| | - Marieke von Lindern
- Department Hematopoiesis, Sanquin Research, and Landsteiner Laboratory, Amsterdam University Medical Centre, 1066CX Amsterdam, The Netherlands; (M.H.); (S.Z.); (F.d.S.); (K.S.M.); (D.C.T.-T.); (E.v.d.A.)
- Correspondence: ; Tel.: +31-6-1203-7801
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Sen NE, Arsovic A, Meierhofer D, Brodesser S, Oberschmidt C, Canet-Pons J, Kaya ZE, Halbach MV, Gispert S, Sandhoff K, Auburger G. In Human and Mouse Spino-Cerebellar Tissue, Ataxin-2 Expansion Affects Ceramide-Sphingomyelin Metabolism. Int J Mol Sci 2019; 20:E5854. [PMID: 31766565 PMCID: PMC6928749 DOI: 10.3390/ijms20235854] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2019] [Revised: 11/19/2019] [Accepted: 11/20/2019] [Indexed: 02/08/2023] Open
Abstract
Ataxin-2 (human gene symbol ATXN2) acts during stress responses, modulating mRNA translation and nutrient metabolism. Ataxin-2 knockout mice exhibit progressive obesity, dyslipidemia, and insulin resistance. Conversely, the progressive ATXN2 gain of function due to the fact of polyglutamine (polyQ) expansions leads to a dominantly inherited neurodegenerative process named spinocerebellar ataxia type 2 (SCA2) with early adipose tissue loss and late muscle atrophy. We tried to understand lipid dysregulation in a SCA2 patient brain and in an authentic mouse model. Thin layer chromatography of a patient cerebellum was compared to the lipid metabolome of Atxn2-CAG100-Knockin (KIN) mouse spinocerebellar tissue. The human pathology caused deficits of sulfatide, galactosylceramide, cholesterol, C22/24-sphingomyelin, and gangliosides GM1a/GD1b despite quite normal levels of C18-sphingomyelin. Cerebellum and spinal cord from the KIN mouse showed a consistent decrease of various ceramides with a significant elevation of sphingosine in the more severely affected spinal cord. Deficiency of C24/26-sphingomyelins contrasted with excess C18/20-sphingomyelin. Spinocerebellar expression profiling revealed consistent reductions of CERS protein isoforms, Sptlc2 and Smpd3, but upregulation of Cers2 mRNA, as prominent anomalies in the ceramide-sphingosine metabolism. Reduction of Asah2 mRNA correlated to deficient S1P levels. In addition, downregulations for the elongase Elovl1, Elovl4, Elovl5 mRNAs and ELOVL4 protein explain the deficit of very long-chain sphingomyelin. Reduced ASMase protein levels correlated to the accumulation of long-chain sphingomyelin. Overall, a deficit of myelin lipids was prominent in SCA2 nervous tissue at prefinal stage and not compensated by transcriptional adaptation of several metabolic enzymes. Myelination is controlled by mTORC1 signals; thus, our human and murine observations are in agreement with the known role of ATXN2 yeast, nematode, and mouse orthologs as mTORC1 inhibitors and autophagy promoters.
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Affiliation(s)
- Nesli-Ece Sen
- Experimental Neurology, Building 89, Goethe University Medical Faculty, Theodor Stern Kai 7, 60590 Frankfurt am Main, Germany; (N.-E.S.); (A.A.); (C.O.); (J.C.-P.); (Z.-E.K.); (M.-V.H.); (S.G.)
- Faculty of Biosciences, Goethe-University, 60438 Frankfurt am Main, Germany
| | - Aleksandar Arsovic
- Experimental Neurology, Building 89, Goethe University Medical Faculty, Theodor Stern Kai 7, 60590 Frankfurt am Main, Germany; (N.-E.S.); (A.A.); (C.O.); (J.C.-P.); (Z.-E.K.); (M.-V.H.); (S.G.)
| | - David Meierhofer
- Max Planck Institute for Molecular Genetics, Ihnestrasse 63-73, 14195 Berlin, Germany;
| | - Susanne Brodesser
- Membrane Biology and Lipid Biochemistry Unit, Life and Medical Sciences Institute, University of Bonn, 53121 Bonn, Germany;
| | - Carola Oberschmidt
- Experimental Neurology, Building 89, Goethe University Medical Faculty, Theodor Stern Kai 7, 60590 Frankfurt am Main, Germany; (N.-E.S.); (A.A.); (C.O.); (J.C.-P.); (Z.-E.K.); (M.-V.H.); (S.G.)
| | - Júlia Canet-Pons
- Experimental Neurology, Building 89, Goethe University Medical Faculty, Theodor Stern Kai 7, 60590 Frankfurt am Main, Germany; (N.-E.S.); (A.A.); (C.O.); (J.C.-P.); (Z.-E.K.); (M.-V.H.); (S.G.)
| | - Zeynep-Ece Kaya
- Experimental Neurology, Building 89, Goethe University Medical Faculty, Theodor Stern Kai 7, 60590 Frankfurt am Main, Germany; (N.-E.S.); (A.A.); (C.O.); (J.C.-P.); (Z.-E.K.); (M.-V.H.); (S.G.)
- Cerrahpasa School of Medicine, Istanbul University, 34098 Istanbul, Turkey
| | - Melanie-Vanessa Halbach
- Experimental Neurology, Building 89, Goethe University Medical Faculty, Theodor Stern Kai 7, 60590 Frankfurt am Main, Germany; (N.-E.S.); (A.A.); (C.O.); (J.C.-P.); (Z.-E.K.); (M.-V.H.); (S.G.)
| | - Suzana Gispert
- Experimental Neurology, Building 89, Goethe University Medical Faculty, Theodor Stern Kai 7, 60590 Frankfurt am Main, Germany; (N.-E.S.); (A.A.); (C.O.); (J.C.-P.); (Z.-E.K.); (M.-V.H.); (S.G.)
| | - Konrad Sandhoff
- Membrane Biology and Lipid Biochemistry Unit, Life and Medical Sciences Institute, University of Bonn, 53121 Bonn, Germany;
| | - Georg Auburger
- Experimental Neurology, Building 89, Goethe University Medical Faculty, Theodor Stern Kai 7, 60590 Frankfurt am Main, Germany; (N.-E.S.); (A.A.); (C.O.); (J.C.-P.); (Z.-E.K.); (M.-V.H.); (S.G.)
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Xu F, Kula-Eversole E, Iwanaszko M, Lim C, Allada R. Ataxin2 functions via CrebA to mediate Huntingtin toxicity in circadian clock neurons. PLoS Genet 2019; 15:e1008356. [PMID: 31593562 PMCID: PMC6782096 DOI: 10.1371/journal.pgen.1008356] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2019] [Accepted: 08/07/2019] [Indexed: 12/12/2022] Open
Abstract
Disrupted circadian rhythms is a prominent and early feature of neurodegenerative diseases including Huntington’s disease (HD). In HD patients and animal models, striatal and hypothalamic neurons expressing molecular circadian clocks are targets of mutant Huntingtin (mHtt) pathogenicity. Yet how mHtt disrupts circadian rhythms remains unclear. In a genetic screen for modifiers of mHtt effects on circadian behavior in Drosophila, we discovered a role for the neurodegenerative disease gene Ataxin2 (Atx2). Genetic manipulations of Atx2 modify the impact of mHtt on circadian behavior as well as mHtt aggregation and demonstrate a role for Atx2 in promoting mHtt aggregation as well as mHtt-mediated neuronal dysfunction. RNAi knockdown of the Fragile X mental retardation gene, dfmr1, an Atx2 partner, also partially suppresses mHtt effects and Atx2 effects depend on dfmr1. Atx2 knockdown reduces the cAMP response binding protein A (CrebA) transcript at dawn. CrebA transcript level shows a prominent diurnal regulation in clock neurons. Loss of CrebA also partially suppresses mHtt effects on behavior and cell loss and restoration of CrebA can suppress Atx2 effects. Our results indicate a prominent role of Atx2 in mediating mHtt pathology, specifically via its regulation of CrebA, defining a novel molecular pathway in HD pathogenesis. Circadian clocks evolved to anticipate 24 h environmental rhythms driven by the earth’s daily rotation and regulate nearly all aspects of behavior, physiology and the genome. Disruptions of the circadian clock have been associated with a wide range of human diseases, including neurodegenerative diseases such as Huntington’s disease (HD). Using an HD animal model in which a mutant Huntingtin (mHtt) protein is expressed, we identify a role for the RNA binding protein and neurodegenerative disease gene Ataxin-2 (Atx2) in mediating mHtt effects on circadian behavioral rhythms. Using transcriptomics, we identify the transcription factor CrebA as a potential target of both Atx2 and the circadian clock. Finally, we demonstrate a role for CrebA in mediating mHtt effects on circadian behavior, defining a novel Atx2-CrebA pathway in a neurodegenerative disease model. These studies define the molecular mechanisms by which mHtt can disrupt circadian rhythms identifying potential novel therapeutic targets for this uniformly fatal disease.
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Affiliation(s)
- Fangke Xu
- Department of Neurobiology, Northwestern University, Evanston, Illinois, United States of America
| | - Elzbieta Kula-Eversole
- Department of Neurobiology, Northwestern University, Evanston, Illinois, United States of America
| | - Marta Iwanaszko
- Feinberg School of Medicine, Northwestern University, Chicago, Illinois, United States of America
| | - Chunghun Lim
- Department of Neurobiology, Northwestern University, Evanston, Illinois, United States of America
| | - Ravi Allada
- Department of Neurobiology, Northwestern University, Evanston, Illinois, United States of America
- * E-mail:
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Abstract
The effective therapeutic treatment and the disease-modifying therapy for spinocerebellar ataxia type 2 (SCA2) (a progressive hereditary disease caused by an expansion of polyglutamine in the ataxin-2 protein) is not available yet. At present, only symptomatic treatment and methods of palliative care are prescribed to the patients. Many attempts were made to study the physiological, molecular, and biochemical changes in SCA2 patients and in a variety of the model systems to find new therapeutic targets for SCA2 treatment. A better understanding of the uncovered molecular mechanisms of the disease allowed the scientific community to develop strategies of potential therapy and helped to create some promising therapeutic approaches for SCA2 treatment. Recent progress in this field will be discussed in this review article.
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Affiliation(s)
- Polina A Egorova
- Laboratory of Molecular Neurodegeneration, Peter the Great St.Petersburg Polytechnic University, St. Petersburg, 195251, Russia
| | - Ilya B Bezprozvanny
- Laboratory of Molecular Neurodegeneration, Peter the Great St.Petersburg Polytechnic University, St. Petersburg, 195251, Russia.
- Department of Physiology, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, ND12.200, Dallas, Texas, 75390, USA.
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Park S, Park SK, Watanabe N, Hashimoto T, Iwatsubo T, Shelkovnikova TA, Liebman SW. Calcium-responsive transactivator (CREST) toxicity is rescued by loss of PBP1/ATXN2 function in a novel yeast proteinopathy model and in transgenic flies. PLoS Genet 2019; 15:e1008308. [PMID: 31390360 PMCID: PMC6699716 DOI: 10.1371/journal.pgen.1008308] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2019] [Revised: 08/19/2019] [Accepted: 07/12/2019] [Indexed: 12/26/2022] Open
Abstract
Proteins associated with familial neurodegenerative disease often aggregate in patients’ neurons. Several such proteins, e.g. TDP-43, aggregate and are toxic when expressed in yeast. Deletion of the ATXN2 ortholog, PBP1, reduces yeast TDP-43 toxicity, which led to identification of ATXN2 as an amyotrophic lateral sclerosis (ALS) risk factor and therapeutic target. Likewise, new yeast neurodegenerative disease models could facilitate identification of other risk factors and targets. Mutations in SS18L1, encoding the calcium-responsive transactivator (CREST) chromatin-remodeling protein, are associated with ALS. We show that CREST is toxic in yeast and forms nuclear and occasionally cytoplasmic foci that stain with Thioflavin-T, a dye indicative of amyloid-like protein. Like the yeast chromatin-remodeling factor SWI1, CREST inhibits silencing of FLO genes. Toxicity of CREST is enhanced by the [PIN+] prion and reduced by deletion of the HSP104 chaperone required for the propagation of many yeast prions. Likewise, deletion of PBP1 reduced CREST toxicity and aggregation. In accord with the yeast data, we show that the Drosophila ortholog of human ATXN2, dAtx2, is a potent enhancer of CREST toxicity. Downregulation of dAtx2 in flies overexpressing CREST in retinal ganglion cells was sufficient to largely rescue the severe degenerative phenotype induced by human CREST. Overexpression caused considerable co-localization of CREST and PBP1/ATXN2 in cytoplasmic foci in both yeast and mammalian cells. Thus, co-aggregation of CREST and PBP1/ATXN2 may serve as one of the mechanisms of PBP1/ATXN2-mediated toxicity. These results extend the spectrum of ALS associated proteins whose toxicity is regulated by PBP1/ATXN2, suggesting that therapies targeting ATXN2 may be effective for a wide range of neurodegenerative diseases. Mutations in the calcium-responsive transactivator (CREST) protein have been shown to cause amyotrophic lateral sclerosis (ALS). Here we show that the human CREST protein expressed in yeast forms largely nuclear aggregates and is toxic. We also show that the HSP104 chaperone required for propagation of yeast prions is likewise required for CREST toxicity. Furthermore deletion of HSP104 affects CREST aggregation. ATXN2, previously shown to modify ALS toxicity caused by mutations in the TDP-43 encoding gene, also modifies toxicity of CREST expressed in either yeast or flies. In addition, deletion of the yeast ATXN2 ortholog reduces CREST aggregation. These results extend the spectrum of ALS associated proteins whose toxicity is regulated by ATXN2, suggesting that therapies targeting ATXN2 may be effective for a wide range of neurodegenerative diseases.
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Affiliation(s)
- Sangeun Park
- Department of Pharmacology, University of Nevada, Reno, Untied States of America
| | - Sei-Kyoung Park
- Department of Pharmacology, University of Nevada, Reno, Untied States of America
| | | | | | | | | | - Susan W. Liebman
- Department of Pharmacology, University of Nevada, Reno, Untied States of America
- * E-mail:
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26
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Bakthavachalu B, Huelsmeier J, Sudhakaran IP, Hillebrand J, Singh A, Petrauskas A, Thiagarajan D, Sankaranarayanan M, Mizoue L, Anderson EN, Pandey UB, Ross E, VijayRaghavan K, Parker R, Ramaswami M. RNP-Granule Assembly via Ataxin-2 Disordered Domains Is Required for Long-Term Memory and Neurodegeneration. Neuron 2018; 98:754-766.e4. [PMID: 29772202 DOI: 10.1016/j.neuron.2018.04.032] [Citation(s) in RCA: 71] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2017] [Revised: 03/07/2018] [Accepted: 04/23/2018] [Indexed: 02/07/2023]
Abstract
Human Ataxin-2 is implicated in the cause and progression of amyotrophic lateral sclerosis (ALS) and type 2 spinocerebellar ataxia (SCA-2). In Drosophila, a conserved atx2 gene is essential for animal survival as well as for normal RNP-granule assembly, translational control, and long-term habituation. Like its human homolog, Drosophila Ataxin-2 (Atx2) contains polyQ repeats and additional intrinsically disordered regions (IDRs). We demonstrate that Atx2 IDRs, which are capable of mediating liquid-liquid phase transitions in vitro, are essential for efficient formation of neuronal mRNP assemblies in vivo. Remarkably, ΔIDR mutants that lack neuronal RNP granules show normal animal development, survival, and fertility. However, they show defects in long-term memory formation/consolidation as well as in C9ORF72 dipeptide repeat or FUS-induced neurodegeneration. Together, our findings demonstrate (1) that higher-order mRNP assemblies contribute to long-term neuronal plasticity and memory, and (2) that a targeted reduction in RNP-granule formation efficiency can alleviate specific forms of neurodegeneration.
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Affiliation(s)
| | - Joern Huelsmeier
- Trinity College Institute of Neuroscience, School of Genetics and Microbiology, Smurfit Institute of Genetics and School of Natural Sciences, Trinity College Dublin, Dublin-2, Ireland
| | | | - Jens Hillebrand
- Trinity College Institute of Neuroscience, School of Genetics and Microbiology, Smurfit Institute of Genetics and School of Natural Sciences, Trinity College Dublin, Dublin-2, Ireland
| | - Amanjot Singh
- National Centre for Biological Sciences, TIFR, Bangalore 560065, India
| | - Arnas Petrauskas
- Trinity College Institute of Neuroscience, School of Genetics and Microbiology, Smurfit Institute of Genetics and School of Natural Sciences, Trinity College Dublin, Dublin-2, Ireland
| | | | | | - Laura Mizoue
- Department of Chemistry, University of Colorado, Boulder, CO 80309, USA; HHMI, University of Colorado, Boulder, CO 80309, USA
| | - Eric N Anderson
- Department of Pediatrics, Children's Hospital of Pittsburgh, University of Pittsburgh School of Medicine, Pittsburgh, PA 15261, USA
| | - Udai Bhan Pandey
- Department of Pediatrics, Children's Hospital of Pittsburgh, University of Pittsburgh School of Medicine, Pittsburgh, PA 15261, USA
| | - Eric Ross
- Department of Biochemistry and Molecular Biology, Colorado State University, Fort Collins, CO 80523, USA
| | - K VijayRaghavan
- National Centre for Biological Sciences, TIFR, Bangalore 560065, India
| | - Roy Parker
- Department of Chemistry, University of Colorado, Boulder, CO 80309, USA; HHMI, University of Colorado, Boulder, CO 80309, USA
| | - Mani Ramaswami
- National Centre for Biological Sciences, TIFR, Bangalore 560065, India; Trinity College Institute of Neuroscience, School of Genetics and Microbiology, Smurfit Institute of Genetics and School of Natural Sciences, Trinity College Dublin, Dublin-2, Ireland.
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27
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Abstract
Ataxin-2 is an RNA-binding protein involved in translation regulation and mutated in neurodegenerative diseases, including ALS. In this issue of Neuron, Bakthavachalu et al. (2018) demonstrate that higher-order ataxin-2 RNA/protein assemblies are necessary for both translation-dependent learning and ALS-associated neurodegeneration in Drosophila.
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Affiliation(s)
- Lindsay A Becker
- Department of Genetics, Stanford University School of Medicine, Stanford, CA 94305, USA; Neurosciences Graduate Program, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Aaron D Gitler
- Department of Genetics, Stanford University School of Medicine, Stanford, CA 94305, USA.
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28
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Zhang K, Daigle JG, Cunningham KM, Coyne AN, Ruan K, Grima JC, Bowen KE, Wadhwa H, Yang P, Rigo F, Taylor JP, Gitler AD, Rothstein JD, Lloyd TE. Stress Granule Assembly Disrupts Nucleocytoplasmic Transport. Cell 2018; 173:958-971.e17. [PMID: 29628143 DOI: 10.1016/j.cell.2018.03.025] [Citation(s) in RCA: 238] [Impact Index Per Article: 39.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2017] [Revised: 01/08/2018] [Accepted: 03/06/2018] [Indexed: 01/21/2023]
Abstract
Defects in nucleocytoplasmic transport have been identified as a key pathogenic event in amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD) mediated by a GGGGCC hexanucleotide repeat expansion in C9ORF72, the most common genetic cause of ALS/FTD. Furthermore, nucleocytoplasmic transport disruption has also been implicated in other neurodegenerative diseases with protein aggregation, suggesting a shared mechanism by which protein stress disrupts nucleocytoplasmic transport. Here, we show that cellular stress disrupts nucleocytoplasmic transport by localizing critical nucleocytoplasmic transport factors into stress granules, RNA/protein complexes that play a crucial role in ALS pathogenesis. Importantly, inhibiting stress granule assembly, such as by knocking down Ataxin-2, suppresses nucleocytoplasmic transport defects as well as neurodegeneration in C9ORF72-mediated ALS/FTD. Our findings identify a link between stress granule assembly and nucleocytoplasmic transport, two fundamental cellular processes implicated in the pathogenesis of C9ORF72-mediated ALS/FTD and other neurodegenerative diseases.
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Affiliation(s)
- Ke Zhang
- Department of Neurology, School of Medicine, Johns Hopkins University, Baltimore, MD 21205, USA; Brain Science Institute, School of Medicine, Johns Hopkins University, Baltimore, MD 21205, USA
| | - J Gavin Daigle
- Department of Neurology, School of Medicine, Johns Hopkins University, Baltimore, MD 21205, USA; Brain Science Institute, School of Medicine, Johns Hopkins University, Baltimore, MD 21205, USA
| | - Kathleen M Cunningham
- Cellular and Molecular Medicine Program, School of Medicine, Johns Hopkins University, Baltimore, MD 21205, USA
| | - Alyssa N Coyne
- Department of Neurology, School of Medicine, Johns Hopkins University, Baltimore, MD 21205, USA; Brain Science Institute, School of Medicine, Johns Hopkins University, Baltimore, MD 21205, USA
| | - Kai Ruan
- Department of Neurology, School of Medicine, Johns Hopkins University, Baltimore, MD 21205, USA
| | - Jonathan C Grima
- Brain Science Institute, School of Medicine, Johns Hopkins University, Baltimore, MD 21205, USA; Solomon H. Snyder Department of Neuroscience, School of Medicine, Johns Hopkins University, Baltimore, MD 21205, USA
| | - Kelly E Bowen
- Department of Neurology, School of Medicine, Johns Hopkins University, Baltimore, MD 21205, USA; Brain Science Institute, School of Medicine, Johns Hopkins University, Baltimore, MD 21205, USA
| | - Harsh Wadhwa
- Department of Neurology, School of Medicine, Johns Hopkins University, Baltimore, MD 21205, USA
| | - Peiguo Yang
- Department of Cell and Molecular Biology, St. Jude Children's Research Hospital, Memphis, TN 38105, USA
| | - Frank Rigo
- Ionis Pharmaceuticals, Carlsbad, CA 92010, USA
| | - J Paul Taylor
- Department of Cell and Molecular Biology, St. Jude Children's Research Hospital, Memphis, TN 38105, USA; Department of Cell and Molecular Biology, Howard Hughes Medical Institute, St. Jude Children's Research Hospital, Memphis, TN 38105, USA
| | - Aaron D Gitler
- Department of Genetics, Stanford University, School of Medicine, Stanford, CA 94305, USA
| | - Jeffrey D Rothstein
- Department of Neurology, School of Medicine, Johns Hopkins University, Baltimore, MD 21205, USA; Brain Science Institute, School of Medicine, Johns Hopkins University, Baltimore, MD 21205, USA; Cellular and Molecular Medicine Program, School of Medicine, Johns Hopkins University, Baltimore, MD 21205, USA; Solomon H. Snyder Department of Neuroscience, School of Medicine, Johns Hopkins University, Baltimore, MD 21205, USA.
| | - Thomas E Lloyd
- Department of Neurology, School of Medicine, Johns Hopkins University, Baltimore, MD 21205, USA; Cellular and Molecular Medicine Program, School of Medicine, Johns Hopkins University, Baltimore, MD 21205, USA; Solomon H. Snyder Department of Neuroscience, School of Medicine, Johns Hopkins University, Baltimore, MD 21205, USA.
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29
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Speck S, Kern T, Aistleitner K, Dilcher M, Dobler G, Essbauer S. In vitro studies of Rickettsia-host cell interactions: Confocal laser scanning microscopy of Rickettsia helvetica-infected eukaryotic cell lines. PLoS Negl Trop Dis 2018; 12:e0006151. [PMID: 29432420 PMCID: PMC5825168 DOI: 10.1371/journal.pntd.0006151] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2017] [Revised: 02/23/2018] [Accepted: 12/04/2017] [Indexed: 11/19/2022] Open
Abstract
Rickettsia (R.) helvetica is the most prevalent rickettsia found in Ixodes ricinus ticks in Germany. Several studies reported antibodies against R. helvetica up to 12.5% in humans investigated, however, fulminant clinical cases are rare indicating a rather low pathogenicity compared to other rickettsiae. We investigated growth characteristics of R. helvetica isolate AS819 in two different eukaryotic cell lines with focus on ultra-structural changes of host cells during infection determined by confocal laser scanning microscopy. Further investigations included partially sequencing of rickA, sca4 and sca2 genes, which have been reported to encode proteins involved in cell-to-cell spread and virulence in some rickettsiae. R. helvetica grew constantly but slowly in both cell lines used. Confocal laser scanning microscopy revealed that the dissemination of R. helvetica AS819 in both cell lines was rather mediated by cell break-down and bacterial release than cell-to-cell spread. The cytoskeleton of both investigated eukaryotic cell lines was not altered. R. helvetica possesses rickA, but its expression is not sufficient to promote actin-based motility as demonstrated by confocal laser scanning microscopy. Hypothetical Sca2 and Sca4 proteins were deduced from nucleotide gene sequences but the predicted amino acid sequences were disrupted or truncated compared to other rickettsiae most likely resulting in non-functional proteins. Taken together, these results might give a first hint to the underlying causes of the reduced virulence and pathogenicity of R. helvetica.
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Affiliation(s)
- Stephanie Speck
- Bundeswehr Institute of Microbiology, German Center of Infection Research DZIF Partner, Munich, Bavaria, Germany
| | - Tanja Kern
- Bundeswehr Institute of Microbiology, German Center of Infection Research DZIF Partner, Munich, Bavaria, Germany
| | - Karin Aistleitner
- Bundeswehr Institute of Microbiology, German Center of Infection Research DZIF Partner, Munich, Bavaria, Germany
| | - Meik Dilcher
- University Medical Center Göttingen, Department of Virology, Göttingen, Lower Saxony, Germany
| | - Gerhard Dobler
- Bundeswehr Institute of Microbiology, German Center of Infection Research DZIF Partner, Munich, Bavaria, Germany
| | - Sandra Essbauer
- Bundeswehr Institute of Microbiology, German Center of Infection Research DZIF Partner, Munich, Bavaria, Germany
- * E-mail:
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30
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Farhan SMK, Gendron TF, Petrucelli L, Hegele RA, Strong MJ. OPTN p.Met468Arg and ATXN2 intermediate length polyQ extension in families with C9orf72 mediated amyotrophic lateral sclerosis and frontotemporal dementia. Am J Med Genet B Neuropsychiatr Genet 2018; 177:75-85. [PMID: 29080331 DOI: 10.1002/ajmg.b.32606] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/23/2017] [Accepted: 09/27/2017] [Indexed: 12/12/2022]
Abstract
We have ascertained two families affected with familial amyotrophic lateral sclerosis (ALS) in which they both carry a hexanucleotide repeat expansion in the C9orf72 gene, specifically in individuals who also presented with frontotemporal dementia (FTD) or behavioral variant FTD (bvFTD). While some reports attribute this phenotypic heterogeneity to the C9orf72 expansion alone, we screened for additional genetic variation in known ALS-FTD genes that may also contribute to or modify the phenotypes. We performed genetic testing consisting of C9orf72 hexanucleotide expansion, ATXN2 polyglutamine (polyQ) expansion, and targeted next generation sequencing using the ONDRISeq, a gene panel consisting of 80 genes known to be associated with neurodegenerative diseases such as ALS, FTD, Alzheimer's disease, Parkinson's disease, and vascular cognitive impairment. In addition to the C9orf72 expansion, we observed an ATXN2 polyQ intermediate length expansion, and OPTN p.Met468Arg in patients who exhibited ALS and FTD or bvFTD. We conclude that the C9orf72 expansion likely explains much of the ALS-FTD phenotype; however, inheritance of these additional variants likely modifies the disease course and may provide further evidence for biologically relevant oligogenic inheritance in ALS.
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Affiliation(s)
- Sali M K Farhan
- Robarts Research Institute, Schulich School of Medicine and Dentistry, Western University, London, Ontario, Canada
- Department of Biochemistry, Schulich School of Medicine and Dentistry, Western University, London, Ontario, Canada
| | - Tania F Gendron
- Department of Neuroscience, Mayo Clinic, Jacksonville, Florida
| | | | - Robert A Hegele
- Robarts Research Institute, Schulich School of Medicine and Dentistry, Western University, London, Ontario, Canada
- Department of Biochemistry, Schulich School of Medicine and Dentistry, Western University, London, Ontario, Canada
| | - Michael J Strong
- Robarts Research Institute, Schulich School of Medicine and Dentistry, Western University, London, Ontario, Canada
- Department of Clinical Neurological Sciences, Schulich School of Medicine & Dentistry, Western University, London, Ontario, Canada
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31
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Pflieger LT, Dansithong W, Paul S, Scoles DR, Figueroa KP, Meera P, Otis TS, Facelli JC, Pulst SM. Gene co-expression network analysis for identifying modules and functionally enriched pathways in SCA2. Hum Mol Genet 2017; 26:3069-3080. [PMID: 28525545 PMCID: PMC5886232 DOI: 10.1093/hmg/ddx191] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2017] [Revised: 04/22/2017] [Accepted: 05/11/2017] [Indexed: 12/22/2022] Open
Abstract
Spinocerebellar ataxia type 2 (SCA2) is an autosomal dominant neurodegenerative disease caused by CAG repeat expansion in the ATXN2 gene. The repeat resides in an encoded region of the gene resulting in polyglutamine (polyQ) expansion which has been assumed to result in gain of function, predominantly, for the ATXN2 protein. We evaluated temporal cerebellar expression profiles by RNA sequencing of ATXN2Q127 mice versus wild-type (WT) littermates. ATXN2Q127 mice are characterized by a progressive motor phenotype onset, and have progressive cerebellar molecular and neurophysiological (Purkinje cell firing frequency) phenotypes. Our analysis revealed previously uncharacterized early and progressive abnormal patterning of cerebellar gene expression. Weighted Gene Coexpression Network Analysis revealed four gene modules that were significantly correlated with disease status, composed primarily of genes associated with GTPase signaling, calcium signaling and cell death. Of these genes, few overlapped with differentially expressed cerebellar genes that we identified in Atxn2-/- knockout mice versus WT littermates, suggesting that loss-of-function is not a significant component of disease pathology. We conclude that SCA2 is a disease characterized by gain of function for ATXN2.
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Affiliation(s)
| | - Warunee Dansithong
- Department of Neurology, University of Utah, Salt Lake City, UT 84112, USA
| | - Sharan Paul
- Department of Neurology, University of Utah, Salt Lake City, UT 84112, USA
| | - Daniel R. Scoles
- Department of Neurology, University of Utah, Salt Lake City, UT 84112, USA
| | - Karla P. Figueroa
- Department of Neurology, University of Utah, Salt Lake City, UT 84112, USA
| | - Pratap Meera
- Department of Neurobiology, University of California Los Angeles, Los Angeles, CA, USA
| | - Thomas S. Otis
- Department of Neurobiology, University of California Los Angeles, Los Angeles, CA, USA
| | | | - Stefan M. Pulst
- Department of Neurology, University of Utah, Salt Lake City, UT 84112, USA
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32
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Becker LA, Huang B, Bieri G, Ma R, Knowles DA, Jafar-Nejad P, Messing J, Kim HJ, Soriano A, Auburger G, Pulst SM, Taylor JP, Rigo F, Gitler AD. Therapeutic reduction of ataxin-2 extends lifespan and reduces pathology in TDP-43 mice. Nature 2017; 544:367-371. [PMID: 28405022 PMCID: PMC5642042 DOI: 10.1038/nature22038] [Citation(s) in RCA: 350] [Impact Index Per Article: 50.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2016] [Accepted: 03/02/2017] [Indexed: 11/25/2022]
Abstract
Amyotrophic lateral sclerosis (ALS) is a rapidly progressing neurodegenerative disease that is characterized by motor neuron loss and that leads to paralysis and death 2-5 years after disease onset. Nearly all patients with ALS have aggregates of the RNA-binding protein TDP-43 in their brains and spinal cords, and rare mutations in the gene encoding TDP-43 can cause ALS. There are no effective TDP-43-directed therapies for ALS or related TDP-43 proteinopathies, such as frontotemporal dementia. Antisense oligonucleotides (ASOs) and RNA-interference approaches are emerging as attractive therapeutic strategies in neurological diseases. Indeed, treatment of a rat model of inherited ALS (caused by a mutation in Sod1) with ASOs against Sod1 has been shown to substantially slow disease progression. However, as SOD1 mutations account for only around 2-5% of ALS cases, additional therapeutic strategies are needed. Silencing TDP-43 itself is probably not appropriate, given its critical cellular functions. Here we present a promising alternative therapeutic strategy for ALS that involves targeting ataxin-2. A decrease in ataxin-2 suppresses TDP-43 toxicity in yeast and flies, and intermediate-length polyglutamine expansions in the ataxin-2 gene increase risk of ALS. We used two independent approaches to test whether decreasing ataxin-2 levels could mitigate disease in a mouse model of TDP-43 proteinopathy. First, we crossed ataxin-2 knockout mice with TDP-43 (also known as TARDBP) transgenic mice. The decrease in ataxin-2 reduced aggregation of TDP-43, markedly increased survival and improved motor function. Second, in a more therapeutically applicable approach, we administered ASOs targeting ataxin-2 to the central nervous system of TDP-43 transgenic mice. This single treatment markedly extended survival. Because TDP-43 aggregation is a component of nearly all cases of ALS, targeting ataxin-2 could represent a broadly effective therapeutic strategy.
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Affiliation(s)
- Lindsay A. Becker
- Department of Genetics, Stanford University School of Medicine, Stanford, CA 94305, USA
- Stanford Neurosciences Graduate Program, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Brenda Huang
- Department of Genetics, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Gregor Bieri
- Department of Genetics, Stanford University School of Medicine, Stanford, CA 94305, USA
- Stanford Neurosciences Graduate Program, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Rosanna Ma
- Department of Genetics, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - David A. Knowles
- Department of Genetics, Stanford University School of Medicine, Stanford, CA 94305, USA
| | | | - James Messing
- Department of Cell and Molecular Biology, St. Jude Children’s Research Hospital, Memphis, TN 38105, USA
| | - Hong Joo Kim
- Department of Cell and Molecular Biology, St. Jude Children’s Research Hospital, Memphis, TN 38105, USA
| | | | - Georg Auburger
- Experimental Neurology, Department of Neurology, Goethe University, 60590, Frankfurt am Main, Germany
| | - Stefan M. Pulst
- Department of Neurology, University of Utah, Salt Lake City, UT 84112 USA
| | - J. Paul Taylor
- Department of Cell and Molecular Biology, St. Jude Children’s Research Hospital, Memphis, TN 38105, USA
- Howard Hughes Medical Institute, Chevy Chase, MD 20815, USA
| | - Frank Rigo
- Ionis Pharmaceuticals, Carlsbad, CA 92010, USA
| | - Aaron D. Gitler
- Department of Genetics, Stanford University School of Medicine, Stanford, CA 94305, USA
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33
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Sproviero W, Shatunov A, Stahl D, Shoai M, van Rheenen W, Jones AR, Al-Sarraj S, Andersen PM, Bonini NM, Conforti FL, Van Damme P, Daoud H, Del Mar Amador M, Fogh I, Forzan M, Gaastra B, Gellera C, Gitler AD, Hardy J, Fratta P, La Bella V, Le Ber I, Van Langenhove T, Lattante S, Lee YC, Malaspina A, Meininger V, Millecamps S, Orrell R, Rademakers R, Robberecht W, Rouleau G, Ross OA, Salachas F, Sidle K, Smith BN, Soong BW, Sorarù G, Stevanin G, Kabashi E, Troakes C, van Broeckhoven C, Veldink JH, van den Berg LH, Shaw CE, Powell JF, Al-Chalabi A. ATXN2 trinucleotide repeat length correlates with risk of ALS. Neurobiol Aging 2017; 51:178.e1-178.e9. [PMID: 28017481 PMCID: PMC5302215 DOI: 10.1016/j.neurobiolaging.2016.11.010] [Citation(s) in RCA: 77] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2016] [Revised: 11/14/2016] [Accepted: 11/16/2016] [Indexed: 12/13/2022]
Abstract
We investigated a CAG trinucleotide repeat expansion in the ATXN2 gene in amyotrophic lateral sclerosis (ALS). Two new case-control studies, a British dataset of 1474 ALS cases and 567 controls, and a Dutch dataset of 1328 ALS cases and 691 controls were analyzed. In addition, to increase power, we systematically searched PubMed for case-control studies published after 1 August 2010 that investigated the association between ATXN2 intermediate repeats and ALS. We conducted a meta-analysis of the new and existing studies for the relative risks of ATXN2 intermediate repeat alleles of between 24 and 34 CAG trinucleotide repeats and ALS. There was an overall increased risk of ALS for those carrying intermediate sized trinucleotide repeat alleles (odds ratio 3.06 [95% confidence interval 2.37-3.94]; p = 6 × 10-18), with an exponential relationship between repeat length and ALS risk for alleles of 29-32 repeats (R2 = 0.91, p = 0.0002). No relationship was seen for repeat length and age of onset or survival. In contrast to trinucleotide repeat diseases, intermediate ATXN2 trinucleotide repeat expansion in ALS does not predict age of onset but does predict disease risk.
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Affiliation(s)
- William Sproviero
- Department of Basic and Clinical Neuroscience, King's College London, Maurice Wohl Clinical Neuroscience Institute, London, UK
| | - Aleksey Shatunov
- Department of Basic and Clinical Neuroscience, King's College London, Maurice Wohl Clinical Neuroscience Institute, London, UK
| | - Daniel Stahl
- Department of Biostatistics, King's College London, Institute of Psychiatry, Psychology and Neuroscience, London, UK
| | - Maryam Shoai
- Department of Molecular Neuroscience, University College London (UCL) Institute of Neurology, London, UK
| | - Wouter van Rheenen
- Department of Neurology, Brain Center Rudolf Magnus Institute of Neuroscience, University Medical Centre Utrecht, Utrecht, the Netherlands
| | - Ashley R Jones
- Department of Basic and Clinical Neuroscience, King's College London, Maurice Wohl Clinical Neuroscience Institute, London, UK
| | - Safa Al-Sarraj
- Department of Clinical Neuropathology, King's College Hospital NHS Foundation Trust, London, UK
| | - Peter M Andersen
- Department of Pharmacology and Clinical Neuroscience, Umeå University, Umeå, Sweden
| | - Nancy M Bonini
- Department of Biology, University of Pennsylvania, Philadelphia, PA, USA
| | | | - Philip Van Damme
- Neurology Department, University Hospitals Leuven, Leuven, Belgium; Vesalius Research Center, VIB, Leuven, Belgium; Disease (LIND), KU Leuven - University of Leuven, Leuven, Belgium
| | - Hussein Daoud
- Montreal Neurological Institute, McGill University, Montreal, Quebec, Canada
| | - Maria Del Mar Amador
- Department of Nervous System Diseases, ALS Paris ALS Center for Rare Diseases, Groupe Hospitalier Pitié Salpêtrière, APHP, Paris, France
| | - Isabella Fogh
- Department of Basic and Clinical Neuroscience, King's College London, Maurice Wohl Clinical Neuroscience Institute, London, UK
| | - Monica Forzan
- Clinical Genetics Unit, Department of Woman and Child Health, University of Padova, Padova, Italy
| | - Ben Gaastra
- Department of Basic and Clinical Neuroscience, King's College London, Maurice Wohl Clinical Neuroscience Institute, London, UK
| | - Cinzia Gellera
- Fondazione IRCCS Istituto Neurologico Carlo Besta, Milan, Italy
| | - Aaron D Gitler
- Department of Genetics, Stanford University School of Medicine, Stanford, CA, USA
| | - John Hardy
- Department of Molecular Neuroscience, University College London (UCL) Institute of Neurology, London, UK
| | - Pietro Fratta
- Sobell Department of Motor Neuroscience and Movement Disorders, University College London (UCL) Institute of Neurology, London, UK
| | - Vincenzo La Bella
- ALS Clinical Research Center, Bio. Ne. C., University of Palermo, Palermo, Italy
| | - Isabelle Le Ber
- Institut du Cerveau et de la Moelle épinière (ICM), Inserm U1127, CNRS UMR 7225, Sorbonne Universités, UPMC Univ Paris 06 UMRS1127, Paris, France; AP-HP, Hôpitaux Universitaires La Pitié Salpêtrière-Charles Foix, Centre de Référence des Démences Rares, Departement de Neurologie, Paris, France
| | - Tim Van Langenhove
- Neurodegenerative Brain Diseases Group, Department of Molecular Genetics, VIB, Antwerp, Belgium; Laboratory of Neurogenetics, Insititute Born-Bunge, University of Antwerp, Antwerp, Belgium; Department of Neurology, Antwerp University Hospital, Edegem, Belgium
| | - Serena Lattante
- Institut du Cerveau et de la Moelle épinière (ICM), Inserm U1127, CNRS UMR 7225, Sorbonne Universités, UPMC Univ Paris 06 UMRS1127, Paris, France
| | - Yi-Chung Lee
- Department of Neurology, Taipei Veterans General Hospital, Taipei, Taiwan; Department of Neurology, National Yang-Ming University School of Medicine, Taipei, Taiwan; Brain Research Center, National Yang-Ming University, Taipei, Taiwan
| | - Andrea Malaspina
- North-East London and Essex MND Care Centre - Neuroscience and Trauma Centre, Blizard, Institute of Cell and Molecular Medicine, Barts & the London School of Medicine & Dentistry, Barts Health NHS Trust, London, UK
| | - Vincent Meininger
- Hôpital de la Pitié-Salpêtrière, institut de recherche translationnelle en neurosciences (A-ICM), Paris, France; Hôpital de la Pitié-Salpêtrière, réseau SLA IdF, Paris, France
| | - Stéphanie Millecamps
- Institut du Cerveau et de la Moelle épinière (ICM), Inserm U1127, CNRS UMR 7225, Sorbonne Universités, UPMC Univ Paris 06 UMRS1127, Paris, France
| | - Richard Orrell
- Department of Clinical Neuroscience, University College London (UCL) Institute of Neurology, London, UK
| | - Rosa Rademakers
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL, USA
| | - Wim Robberecht
- Vesalius Research Center, VIB, Leuven, Belgium; Disease (LIND), KU Leuven - University of Leuven, Leuven, Belgium
| | - Guy Rouleau
- Montreal Neurological Institute, McGill University, Montreal, Quebec, Canada
| | - Owen A Ross
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL, USA
| | - Francois Salachas
- Department of Nervous System Diseases, ALS Paris ALS Center for Rare Diseases, Groupe Hospitalier Pitié Salpêtrière, APHP, Paris, France; Institut du Cerveau et de la Moelle épinière (ICM), Inserm U1127, CNRS UMR 7225, Sorbonne Universités, UPMC Univ Paris 06 UMRS1127, Paris, France
| | - Katie Sidle
- Department of Molecular Neuroscience, University College London (UCL) Institute of Neurology, London, UK
| | - Bradley N Smith
- Department of Basic and Clinical Neuroscience, King's College London, Maurice Wohl Clinical Neuroscience Institute, London, UK
| | - Bing-Wen Soong
- Department of Neurology, Taipei Veterans General Hospital, Taipei, Taiwan; Department of Neurology, National Yang-Ming University School of Medicine, Taipei, Taiwan; Brain Research Center, National Yang-Ming University, Taipei, Taiwan
| | - Gianni Sorarù
- Department of Neurosciences, University of Padova, Padova, Italy
| | - Giovanni Stevanin
- Institut du Cerveau et de la Moelle épinière (ICM), Inserm U1127, CNRS UMR 7225, Sorbonne Universités, UPMC Univ Paris 06 UMRS1127, Paris, France; Neurogenetics team, Ecole Pratique des Hautes Etudes, Paris, France
| | - Edor Kabashi
- Institut du Cerveau et de la Moelle épinière (ICM), Inserm U1127, CNRS UMR 7225, Sorbonne Universités, UPMC Univ Paris 06 UMRS1127, Paris, France
| | - Claire Troakes
- Department of Basic and Clinical Neuroscience, King's College London, Maurice Wohl Clinical Neuroscience Institute, London, UK
| | - Christine van Broeckhoven
- Neurodegenerative Brain Diseases Group, Department of Molecular Genetics, VIB, Antwerp, Belgium; Laboratory of Neurogenetics, Insititute Born-Bunge, University of Antwerp, Antwerp, Belgium
| | - Jan H Veldink
- Department of Neurology, Brain Center Rudolf Magnus Institute of Neuroscience, University Medical Centre Utrecht, Utrecht, the Netherlands
| | - Leonard H van den Berg
- Department of Neurology, Brain Center Rudolf Magnus Institute of Neuroscience, University Medical Centre Utrecht, Utrecht, the Netherlands
| | - Christopher E Shaw
- Department of Basic and Clinical Neuroscience, King's College London, Maurice Wohl Clinical Neuroscience Institute, London, UK
| | - John F Powell
- Department of Basic and Clinical Neuroscience, King's College London, Maurice Wohl Clinical Neuroscience Institute, London, UK
| | - Ammar Al-Chalabi
- Department of Basic and Clinical Neuroscience, King's College London, Maurice Wohl Clinical Neuroscience Institute, London, UK.
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Flores-Alvarado LJ, Dávalos-Rodríguez NO, García-Cruz D, Madrigal-Ruiz PM, Ruiz-Mejía R, Aguilar-Aldrete ME, Villa-Ruano N, Ramirez-Garcia SA. [(CAG)n polymorphism of the ATXN2 gene, a new marker of susceptibility for type 2 diabetes mellitus]. Rev Panam Salud Publica 2016; 40:318-324. [PMID: 28076580] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2015] [Accepted: 04/25/2016] [Indexed: 06/06/2023] Open
Abstract
OBJECTIVE Estimate whether there is an association between the (CAG)n repeat in the ATXN2 gene in the Mexican population and type 2 diabetes mellitus (DM). METHODS Epidemiological case-control study, including healthy people and diabetics. (CAG)n expansion was detected by end-point polymerase chain reaction (PCR). PCR outputs were analyzed by electrophoresis (PAGE 8%) and silver nitrate staining. RESULTS (CAG)n nucleotide allele distribution in the study population was similar to that reported in central Mexico. The 22-repeat allele is the most frequent; however, there is an association with carriers of long repeats in the normal range with diabetes. CONCLUSIONS The results suggest that the (CAG)n repeat of the ATXN2 gene could be a causal factor for type 2 DM.
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Affiliation(s)
- Luis J Flores-Alvarado
- Departamento de Biología Molecular y Genómica, Centro Universitario de Ciencias de la Salud (CUCS), Benemérita Universidad de Guadalajara, Jalisco, México
| | - Nory O Dávalos-Rodríguez
- Departamento de Biología Molecular y Genómica, Centro Universitario de Ciencias de la Salud (CUCS), Benemérita Universidad de Guadalajara, Jalisco, México
| | - Diana García-Cruz
- Departamento de Biología Molecular y Genómica, Centro Universitario de Ciencias de la Salud (CUCS), Benemérita Universidad de Guadalajara, Jalisco, México
| | - Perla M Madrigal-Ruiz
- Departamento de Biología Molecular y Genómica, Centro Universitario de Ciencias de la Salud (CUCS), Benemérita Universidad de Guadalajara, Jalisco, México
| | - Rosalba Ruiz-Mejía
- Departamento de Biología Molecular y Genómica, Centro Universitario de Ciencias de la Salud (CUCS), Benemérita Universidad de Guadalajara, Jalisco, México
| | - María E Aguilar-Aldrete
- Departamento de Salud Pública, Centro Universitario de Ciencias de la Salud (CUCS), Benemérita Universidad de Guadalajara, Jalisco, México
| | - Nemesio Villa-Ruano
- Instituto de Investigaciones sobre la Salud Pública, Universidad de la Sierra Sur, Miahuatlán de Porfirio Díaz, Oaxaca, México
| | - Sergio Alberto Ramirez-Garcia
- Instituto de Investigaciones sobre la Salud Pública, Universidad de la Sierra Sur, Miahuatlán de Porfirio Díaz, Oaxaca, México
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Heu CC, Kurtti TJ, Nelson CM, Munderloh UG. Transcriptional Analysis of the Conjugal Transfer Genes of Rickettsia bellii RML 369-C. PLoS One 2015; 10:e0137214. [PMID: 26352829 PMCID: PMC4564193 DOI: 10.1371/journal.pone.0137214] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2015] [Accepted: 08/13/2015] [Indexed: 11/19/2022] Open
Abstract
Rickettsia bellii is an obligate intracellular bacterium that is one of the few rickettsiae that encode a complete set of conjugative transfer (tra) genes involved in bacterial conjugation and has been shown to exhibit pili-like structures. The reductive genomes of rickettsiae beg the question whether the tra genes are nonfunctional or functioning to enhance the genetic plasticity and biology of rickettsiae. We characterized the transcriptional dynamics of R. bellii tra genes in comparison to genes transcribed stably and above the background level to understand when and at what levels the tra genes are active or whether the tra genes are degenerative. We determined that the best reference genes, out of 10 tested, were methionyl tRNA ligase (metG) or a combination of metG and ribonucleoside diphosphate reductase 2 subunit beta (nrdF), using statistical algorithms from two different programs: Normfinder and BestKeeper. To validate the use of metG with other rickettsial genes exhibiting variable transcriptional patterns we examined its use with sca2 and rickA, genes involved in actin based motility. Both were shown to be up-regulated at different times of replication in Vero cells, showing variable and stable transcription levels of rickA and sca2, respectively. traATi was up-regulated at 72 hours post inoculation in the tick cell line ISE6, but showed no apparent changes in the monkey cell line Vero and mouse cell line L929. The transcription of tra genes was positively correlated with one another and up-regulated from 12 to 72 hours post inoculation (HPI) when compared to RBE_0422 (an inactivated transposase-derivative found within the tra cluster). Thus, the up-regulation of the tra genes indicated that the integrity and activity of each gene were intact and may facilitate the search for the optimal conditions necessary to demonstrate conjugation in rickettsiae.
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Affiliation(s)
- Chan C. Heu
- Department of Entomology, University of Minnesota, 219 Hodson Hall, 1980 Folwell Ave, St. Paul, Minnesota, United States of America
- * E-mail:
| | - Timothy J. Kurtti
- Department of Entomology, University of Minnesota, 219 Hodson Hall, 1980 Folwell Ave, St. Paul, Minnesota, United States of America
| | - Curtis M. Nelson
- Department of Entomology, University of Minnesota, 219 Hodson Hall, 1980 Folwell Ave, St. Paul, Minnesota, United States of America
| | - Ulrike G. Munderloh
- Department of Entomology, University of Minnesota, 219 Hodson Hall, 1980 Folwell Ave, St. Paul, Minnesota, United States of America
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Borghero G, Pugliatti M, Marrosu F, Marrosu MG, Murru MR, Floris G, Cannas A, Parish LD, Cau TB, Loi D, Ticca A, Traccis S, Manera U, Canosa A, Moglia C, Calvo A, Barberis M, Brunetti M, Renton AE, Nalls MA, Traynor BJ, Restagno G, Chiò A. ATXN2 is a modifier of phenotype in ALS patients of Sardinian ancestry. Neurobiol Aging 2015. [PMID: 26208502 DOI: 10.1016/j.neurobiolaging.2015.06.013] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Intermediate-length CAG expansions (encoding 27-33 glutamines, polyQ) of the Ataxin2 (ATXN2) gene represent a risk factor for amyotrophic lateral sclerosis (ALS). Recently, it has been proposed that ≥31 CAG expansions may influence ALS phenotype. We assessed whether ATXN2 intermediate-length polyQ expansions influence ALS phenotype in a series of 375 patients of Sardinian ancestry. Controls were 247 neurologically healthy subjects, resident in the study area, age- and gender-matched to cases. The frequency of ≥31 polyQ ATNX2 repeats was significantly more common in ALS cases (4 patients vs. no control, p = 0.0001). All patients with ≥31 polyQ repeats had a spinal onset versus 73.3% of patients with <31 polyQ repeats. Patients with an increased number of polyQ repeats have a shorter survival than those with <31 repeats (1.2 vs. 4.2 years, p = 0.035). In this large series of ALS patients of Sardinian ancestry, we have found that ≥31 polyQ repeats of the ATXN2 gene influenced patients' phenotype, being associated to a spinal onset and a significantly shorter survival.
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Affiliation(s)
- Giuseppe Borghero
- Department of Neurology, Azienda Universitario Ospedaliera di Cagliari and University of Cagliari, Cagliari, Italy
| | - Maura Pugliatti
- Department of Clinical and Experimental Medicine, University of Sassari, Sassari, Italy
| | - Francesco Marrosu
- Department of Neurology, Azienda Universitario Ospedaliera di Cagliari and University of Cagliari, Cagliari, Italy
| | | | - Maria Rita Murru
- Multiple Sclerosis Center Laboratory, University of Cagliari, Cagliari, Italy
| | - Gianluca Floris
- Department of Neurology, Azienda Universitario Ospedaliera di Cagliari and University of Cagliari, Cagliari, Italy
| | - Antonino Cannas
- Department of Neurology, Azienda Universitario Ospedaliera di Cagliari and University of Cagliari, Cagliari, Italy
| | - Leslie D Parish
- Department of Clinical and Experimental Medicine, University of Sassari, Sassari, Italy
| | - Tea B Cau
- Azienda Sanitaria Locale n. 2, Olbia-Tempio, Italy
| | - Daniela Loi
- Azienda Sanitaria Locale n. 2, Olbia-Tempio, Italy
| | - Anna Ticca
- Department of Neurology, Azienda Ospedaliera San Francesco, Nuoro, Italy
| | | | - Umberto Manera
- ALS Center, 'Rita Levi Montalcini' Department of Neuroscience, University of Turin, Turin, Italy
| | - Antonio Canosa
- ALS Center, 'Rita Levi Montalcini' Department of Neuroscience, University of Turin, Turin, Italy; Department of Neurosciences, Ophthalmology, Genetics, Rehabilitation and Child Health, University of Genoa, Genoa, Italy
| | - Cristina Moglia
- ALS Center, 'Rita Levi Montalcini' Department of Neuroscience, University of Turin, Turin, Italy
| | - Andrea Calvo
- ALS Center, 'Rita Levi Montalcini' Department of Neuroscience, University of Turin, Turin, Italy; Neurology II, Azienda Ospedaliero Universitaria Città della Salute e della Scienza, Turin, Italy
| | - Marco Barberis
- ALS Center, 'Rita Levi Montalcini' Department of Neuroscience, University of Turin, Turin, Italy; Laboratory of Molecular Genetics, Azienda Ospedaliero Universitaria Città della Salute e della Scienza, Turin, Italy
| | - Maura Brunetti
- ALS Center, 'Rita Levi Montalcini' Department of Neuroscience, University of Turin, Turin, Italy; Laboratory of Molecular Genetics, Azienda Ospedaliero Universitaria Città della Salute e della Scienza, Turin, Italy
| | - Alan E Renton
- Neuromuscular Diseases Research Section, Laboratory of Neurogenetics, National Institute of Aging, Bethesda, USA
| | - Mike A Nalls
- Molecular Genetics Section, Laboratory of Neurogenetics, National Institute of Aging, Bethesda, USA
| | - Bryan J Traynor
- Laboratory of Molecular Genetics, Azienda Ospedaliero Universitaria Città della Salute e della Scienza, Turin, Italy; Brain Science Institute, Department of Neurology, Johns Hopkins University, Baltimore, MD, USA
| | - Gabriella Restagno
- Laboratory of Molecular Genetics, Azienda Ospedaliero Universitaria Città della Salute e della Scienza, Turin, Italy
| | - Adriano Chiò
- ALS Center, 'Rita Levi Montalcini' Department of Neuroscience, University of Turin, Turin, Italy; Neurology II, Azienda Ospedaliero Universitaria Città della Salute e della Scienza, Turin, Italy; Neuroscience Institute of Torino (NIT), Turin, Italy.
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Scoles DR, Ho MHT, Dansithong W, Pflieger LT, Petersen LW, Thai KK, Pulst SM. Repeat Associated Non-AUG Translation (RAN Translation) Dependent on Sequence Downstream of the ATXN2 CAG Repeat. PLoS One 2015; 10:e0128769. [PMID: 26086378 PMCID: PMC4472729 DOI: 10.1371/journal.pone.0128769] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2013] [Accepted: 05/01/2015] [Indexed: 11/18/2022] Open
Abstract
Spinocerebellar ataxia type 2 (SCA2) is a progressive autosomal dominant disorder caused by the expansion of a CAG tract in the ATXN2 gene. The SCA2 disease phenotype is characterized by cerebellar atrophy, gait ataxia, and slow saccades. ATXN2 mutation causes gains of toxic and normal functions of the ATXN2 gene product, ataxin-2, and abnormally slow Purkinje cell firing frequency. Previously we investigated features of ATXN2 controlling expression and noted expression differences for ATXN2 constructs with varying CAG lengths, suggestive of repeat associated non-AUG translation (RAN translation). To determine whether RAN translation occurs for ATXN2 we assembled various ATXN2 constructs with ATXN2 tagged by luciferase, HA or FLAG tags, driven by the CMV promoter or the ATXN2 promoter. Luciferase expression from ATXN2-luciferase constructs lacking the ATXN2 start codon was weak vs AUG translation, regardless of promoter type, and did not increase with longer CAG repeat lengths. RAN translation was detected on western blots by the anti-polyglutamine antibody 1C2 for constructs driven by the CMV promoter but not the ATXN2 promoter, and was weaker than AUG translation. Strong RAN translation was also observed when driving the ATXN2 sequence with the CMV promoter with ATXN2 sequence downstream of the CAG repeat truncated to 18 bp in the polyglutamine frame but not in the polyserine or polyalanine frames. Our data demonstrate that ATXN2 RAN translation is weak compared to AUG translation and is dependent on ATXN2 sequences flanking the CAG repeat.
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Affiliation(s)
- Daniel R. Scoles
- Department of Neurology, University of Utah, 175 North Medical Drive East, 5th Floor, Salt Lake City, Utah, 84132, United States of America
- * E-mail:
| | - Mi H. T. Ho
- Department of Neurology, University of Utah, 175 North Medical Drive East, 5th Floor, Salt Lake City, Utah, 84132, United States of America
| | - Warunee Dansithong
- Department of Neurology, University of Utah, 175 North Medical Drive East, 5th Floor, Salt Lake City, Utah, 84132, United States of America
| | - Lance T. Pflieger
- Department of Neurology, University of Utah, 175 North Medical Drive East, 5th Floor, Salt Lake City, Utah, 84132, United States of America
| | - Lance W. Petersen
- Department of Neurology, University of Utah, 175 North Medical Drive East, 5th Floor, Salt Lake City, Utah, 84132, United States of America
| | - Khanh K. Thai
- Department of Neurology, University of Utah, 175 North Medical Drive East, 5th Floor, Salt Lake City, Utah, 84132, United States of America
| | - Stefan M. Pulst
- Department of Neurology, University of Utah, 175 North Medical Drive East, 5th Floor, Salt Lake City, Utah, 84132, United States of America
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Zhang F, Xu Y, Cao H, Jin C, Cheng Z, Wang G, Shugart YY. Mapsnp: an R package to plot a genomic map for single nucleotide polymorphisms. PLoS One 2015; 10:e0123609. [PMID: 25853637 PMCID: PMC4390227 DOI: 10.1371/journal.pone.0123609] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2014] [Accepted: 03/04/2015] [Indexed: 01/10/2023] Open
Abstract
Single-nucleotide polymorphism (SNP) is one of the most common sources of genetic variations of the genome. Currently, SNPs are a main target for most genetic association studies. Visualizing genomic coordinates of SNPs, including their physical location relative to their host gene, and the structure of the relevant transcripts, may provide intuitive supplements to the understanding of their functions. Nevertheless, to date, no such easy-to-use programming tools exist. Therefore, we developed an R package, "mapsnp", to plot genomic map for a panel of SNPs within a genome region of interest, including the relative chromosome location and the transcripts in the region. mapsnp is a simple and flexible software package which can be used to visualize a genomic map for SNPs, integrating a chromosome ideogram, genomic coordinates, SNP locations and SNP labels.
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Affiliation(s)
- Fuquan Zhang
- Wuxi Mental Health Center of Nanjing Medical University, Wuxi, Jiangsu Province, China
- Unit on Statistical Genomics, Intramural Research Program, National Institute of Mental Health, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Yong Xu
- Department of Psychiatry, First Hospital of Shanxi Medical University, Taiyuan, China
| | - Hongbao Cao
- Unit on Statistical Genomics, Intramural Research Program, National Institute of Mental Health, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Chunhui Jin
- Wuxi Mental Health Center of Nanjing Medical University, Wuxi, Jiangsu Province, China
| | - Zaohuo Cheng
- Wuxi Mental Health Center of Nanjing Medical University, Wuxi, Jiangsu Province, China
| | - Guoqiang Wang
- Wuxi Mental Health Center of Nanjing Medical University, Wuxi, Jiangsu Province, China
- * E-mail: (GW); (YYS)
| | - Yin Yao Shugart
- Unit on Statistical Genomics, Intramural Research Program, National Institute of Mental Health, National Institutes of Health, Bethesda, Maryland, United States of America
- * E-mail: (GW); (YYS)
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Dansithong W, Paul S, Figueroa KP, Rinehart MD, Wiest S, Pflieger LT, Scoles DR, Pulst SM. Ataxin-2 regulates RGS8 translation in a new BAC-SCA2 transgenic mouse model. PLoS Genet 2015; 11:e1005182. [PMID: 25902068 PMCID: PMC4406435 DOI: 10.1371/journal.pgen.1005182] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2014] [Accepted: 03/28/2015] [Indexed: 12/13/2022] Open
Abstract
Spinocerebellar ataxia type 2 (SCA2) is an autosomal dominant disorder with progressive degeneration of cerebellar Purkinje cells (PCs) and other neurons caused by expansion of a glutamine (Q) tract in the ATXN2 protein. We generated BAC transgenic lines in which the full-length human ATXN2 gene was transcribed using its endogenous regulatory machinery. Mice with the ATXN2 BAC transgene with an expanded CAG repeat (BAC-Q72) developed a progressive cellular and motor phenotype, whereas BAC mice expressing wild-type human ATXN2 (BAC-Q22) were indistinguishable from control mice. Expression analysis of laser-capture microdissected (LCM) fractions and regional expression confirmed that the BAC transgene was expressed in PCs and in other neuronal groups such as granule cells (GCs) and neurons in deep cerebellar nuclei as well as in spinal cord. Transcriptome analysis by deep RNA-sequencing revealed that BAC-Q72 mice had progressive changes in steady-state levels of specific mRNAs including Rgs8, one of the earliest down-regulated transcripts in the Pcp2-ATXN2[Q127] mouse line. Consistent with LCM analysis, transcriptome changes analyzed by deep RNA-sequencing were not restricted to PCs, but were also seen in transcripts enriched in GCs such as Neurod1. BAC-Q72, but not BAC-Q22 mice had reduced Rgs8 mRNA levels and even more severely reduced steady-state protein levels. Using RNA immunoprecipitation we showed that ATXN2 interacted selectively with RGS8 mRNA. This interaction was impaired when ATXN2 harbored an expanded polyglutamine. Mutant ATXN2 also reduced RGS8 expression in an in vitro coupled translation assay when compared with equal expression of wild-type ATXN2-Q22. Reduced abundance of Rgs8 in Pcp2-ATXN2[Q127] and BAC-Q72 mice supports our observations of a hyper-excitable mGluR1-ITPR1 signaling axis in SCA2, as RGS proteins are linked to attenuating mGluR1 signaling.
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Affiliation(s)
- Warunee Dansithong
- Department of Neurology, University of Utah, Salt Lake City, Utah, United States of America
| | - Sharan Paul
- Department of Neurology, University of Utah, Salt Lake City, Utah, United States of America
| | - Karla P. Figueroa
- Department of Neurology, University of Utah, Salt Lake City, Utah, United States of America
| | - Marc D. Rinehart
- Department of Neurology, University of Utah, Salt Lake City, Utah, United States of America
| | - Shaina Wiest
- Department of Neurology, University of Utah, Salt Lake City, Utah, United States of America
| | - Lance T. Pflieger
- Department of Neurology, University of Utah, Salt Lake City, Utah, United States of America
| | - Daniel R. Scoles
- Department of Neurology, University of Utah, Salt Lake City, Utah, United States of America
| | - Stefan M. Pulst
- Department of Neurology, University of Utah, Salt Lake City, Utah, United States of America
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