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Tejwani L, Ravindra NG, Lee C, Cheng Y, Nguyen B, Luttik K, Ni L, Zhang S, Morrison LM, Gionco J, Xiang Y, Yoon J, Ro H, Haidery F, Grijalva RM, Bae E, Kim K, Martuscello RT, Orr HT, Zoghbi HY, McLoughlin HS, Ranum LPW, Shakkottai VG, Faust PL, Wang S, van Dijk D, Lim J. Longitudinal single-cell transcriptional dynamics throughout neurodegeneration in SCA1. Neuron 2024; 112:362-383.e15. [PMID: 38016472 PMCID: PMC10922326 DOI: 10.1016/j.neuron.2023.10.039] [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: 12/15/2022] [Revised: 09/10/2023] [Accepted: 10/27/2023] [Indexed: 11/30/2023]
Abstract
Neurodegeneration is a protracted process involving progressive changes in myriad cell types that ultimately results in the death of vulnerable neuronal populations. To dissect how individual cell types within a heterogeneous tissue contribute to the pathogenesis and progression of a neurodegenerative disorder, we performed longitudinal single-nucleus RNA sequencing of mouse and human spinocerebellar ataxia type 1 (SCA1) cerebellar tissue, establishing continuous dynamic trajectories of each cell population. Importantly, we defined the precise transcriptional changes that precede loss of Purkinje cells and, for the first time, identified robust early transcriptional dysregulation in unipolar brush cells and oligodendroglia. Finally, we applied a deep learning method to predict disease state accurately and identified specific features that enable accurate distinction of wild-type and SCA1 cells. Together, this work reveals new roles for diverse cerebellar cell types in SCA1 and provides a generalizable analysis framework for studying neurodegeneration.
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Affiliation(s)
- Leon Tejwani
- Interdepartmental Neuroscience Program, Yale School of Medicine, New Haven, CT 06510, USA; Department of Neuroscience, Yale School of Medicine, New Haven, CT 06510, USA.
| | - Neal G Ravindra
- Cardiovascular Research Center, Section of Cardiovascular Medicine, Department of Internal Medicine, Yale School of Medicine, New Haven, CT 06510, USA; Department of Computer Science, Yale University, New Haven, CT 06510, USA
| | - Changwoo Lee
- Interdepartmental Neuroscience Program, Yale School of Medicine, New Haven, CT 06510, USA; Department of Neuroscience, Yale School of Medicine, New Haven, CT 06510, USA
| | - Yubao Cheng
- Department of Genetics, Yale School of Medicine, New Haven, CT 06510, USA
| | - Billy Nguyen
- University of California, San Francisco School of Medicine, San Francisco, CA 94143, USA
| | - Kimberly Luttik
- Interdepartmental Neuroscience Program, Yale School of Medicine, New Haven, CT 06510, USA; Department of Neuroscience, Yale School of Medicine, New Haven, CT 06510, USA
| | - Luhan Ni
- Department of Genetics, Yale School of Medicine, New Haven, CT 06510, USA
| | - Shupei Zhang
- Department of Genetics, Yale School of Medicine, New Haven, CT 06510, USA
| | - Logan M Morrison
- Department of Neurology, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA; Neuroscience Graduate Program, University of Michigan, Ann Arbor, MI 48109, USA
| | - John Gionco
- Department of Pathology and Cell Biology, Columbia University Irving Medical Center and the New York Presbyterian Hospital, New York, NY 10032, USA
| | - Yangfei Xiang
- Department of Genetics, Yale School of Medicine, New Haven, CT 06510, USA; Yale Stem Cell Center, Yale School of Medicine, New Haven, CT 06510, USA
| | | | - Hannah Ro
- Yale College, New Haven, CT 06510, USA
| | | | - Rosalie M Grijalva
- Interdepartmental Neuroscience Program, Yale School of Medicine, New Haven, CT 06510, USA; Department of Neuroscience, Yale School of Medicine, New Haven, CT 06510, USA
| | | | - Kristen Kim
- Interdepartmental Neuroscience Program, Yale School of Medicine, New Haven, CT 06510, USA; Department of Psychiatry, Yale School of Medicine, New Haven, CT 06510, USA
| | - Regina T Martuscello
- Department of Pathology and Cell Biology, Columbia University Irving Medical Center and the New York Presbyterian Hospital, New York, NY 10032, USA
| | - Harry T Orr
- Department of Laboratory Medicine and Pathology, University of Minnesota, Minneapolis, MN 55455, USA
| | - Huda Y Zoghbi
- Jan and Dan Duncan Neurological Research Institute at Texas Children's Hospital, Houston, TX 77030, USA; Department of Pediatrics, Baylor College of Medicine, Houston, TX 77030, USA; Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA; Howard Hughes Medical Institute, Baylor College of Medicine, Houston, TX 77030, USA
| | - Hayley S McLoughlin
- Department of Neurology, University of Michigan, Ann Arbor, MI 48109-2200, USA
| | - Laura P W Ranum
- Department of Molecular Genetics and Microbiology, Center for Neurogenetics, College of Medicine, Genetics Institute, McKnight Brain Institute, University of Florida, Gainesville, FL 32610, USA
| | - Vikram G Shakkottai
- Department of Neurology, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Phyllis L Faust
- Department of Pathology and Cell Biology, Columbia University Irving Medical Center and the New York Presbyterian Hospital, New York, NY 10032, USA
| | - Siyuan Wang
- Department of Genetics, Yale School of Medicine, New Haven, CT 06510, USA; Department of Cell Biology, Yale School of Medicine, New Haven, CT 06510, USA.
| | - David van Dijk
- Cardiovascular Research Center, Section of Cardiovascular Medicine, Department of Internal Medicine, Yale School of Medicine, New Haven, CT 06510, USA; Department of Computer Science, Yale University, New Haven, CT 06510, USA.
| | - Janghoo Lim
- Interdepartmental Neuroscience Program, Yale School of Medicine, New Haven, CT 06510, USA; Department of Neuroscience, Yale School of Medicine, New Haven, CT 06510, USA; Department of Genetics, Yale School of Medicine, New Haven, CT 06510, USA; Yale Stem Cell Center, Yale School of Medicine, New Haven, CT 06510, USA; Program in Cellular Neuroscience, Neurodegeneration and Repair, Yale School of Medicine, New Haven, CT 06510, USA; Wu Tsai Institute, Yale School of Medicine, New Haven, CT 06510, USA.
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2
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Martins S, Yahia A, Costa IPD, Siddig HE, Abubaker R, Koko M, Corral-Juan M, Matilla-Dueñas A, Brice A, Durr A, Leguern E, Ranum LPW, Amorim A, Elsayed LEO, Stevanin G, Sequeiros J. Machado-Joseph disease in a Sudanese family links East Africa to Portuguese families and allows reestimation of ancestral age of the Machado lineage. Hum Genet 2023; 142:1747-1754. [PMID: 37957369 PMCID: PMC10676304 DOI: 10.1007/s00439-023-02611-8] [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: 08/24/2023] [Accepted: 10/22/2023] [Indexed: 11/15/2023]
Abstract
Machado-Joseph disease (MJD/SCA3) is the most frequent dominant ataxia worldwide. It is caused by a (CAG)n expansion. MJD has two major ancestral backgrounds: the Machado lineage, found mainly in Portuguese families; and the Joseph lineage, present in all five continents, probably originating in Asia. MJD has been described in a few African and African-American families, but here we report the first diagnosed in Sudan to our knowledge. The proband presented with gait ataxia at age 24; followed by muscle cramps and spasticity, and dysarthria, by age 26; he was wheel-chair bound at 29 years of age. His brother had gait problems from age 20 years and, by age 21, lost the ability to run, showed dysarthria and muscle cramps. To assess the mutational origin of this family, we genotyped 30 SNPs and 7 STRs flanking the ATXN3_CAG repeat in three siblings and the non-transmitting father. We compared the MJD haplotype segregating in the family with our cohort of MJD families from diverse populations. Unlike all other known families of African origin, the Machado lineage was observed in Sudan, being shared with 86 Portuguese, 2 Spanish and 2 North-American families. The STR-based haplotype of Sudanese patients, however, was distinct, being four steps (2 STR mutations and 2 recombinations) away from the founder haplotype shared by 47 families, all of Portuguese extraction. Based on the phylogenetic network constructed with all MJD families of the Machado lineage, we estimated a common ancestry at 3211 ± 693 years ago.
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Affiliation(s)
- Sandra Martins
- i3S-Instituto de Investigação e Inovação em Saúde, University of Porto, Porto, Portugal
- IPATIMUP-Institute of Molecular Pathology and Immunology, University of Porto, Porto, Portugal
| | - Ashraf Yahia
- Faculty of Medicine, University of Khartoum, Khartoum, Sudan
- Sorbonne University, Paris Brain Institute - ICM, Inserm, CNRS, AP-HP, Paris, France
- Center of Neurodevelopmental Disorders (KIND), Centre for Psychiatry Research, Department of Women's and Children's Health, Karolinska Institutet and Stockholm Health Care Services, Stockholm, Sweden
| | - Inês P D Costa
- i3S-Instituto de Investigação e Inovação em Saúde, University of Porto, Porto, Portugal
- IPATIMUP-Institute of Molecular Pathology and Immunology, University of Porto, Porto, Portugal
| | - Hassab E Siddig
- Division of Neurology, Sudan Medical Council, Khartoum, Sudan
| | - Rayan Abubaker
- Sudanese Neurogenetics Research Group, Faculty of Medicine, University of Khartoum, Khartoum, Sudan
| | - Mahmoud Koko
- Sudanese Neurogenetics Research Group, Faculty of Medicine, University of Khartoum, Khartoum, Sudan
| | - Marc Corral-Juan
- Functional and Translational Neurogenetics Unit, Department of Neuroscience, Health Sciences Research Institute Germans Trias I Pujol (IGTP)-Universitat Autònoma de Barcelona, Can Ruti Campus, Badalona, Barcelona, Spain
| | - Antoni Matilla-Dueñas
- Functional and Translational Neurogenetics Unit, Department of Neuroscience, Health Sciences Research Institute Germans Trias I Pujol (IGTP)-Universitat Autònoma de Barcelona, Can Ruti Campus, Badalona, Barcelona, Spain
| | - Alexis Brice
- Sorbonne University, Paris Brain Institute - ICM, Inserm, CNRS, AP-HP, Paris, France
| | - Alexandra Durr
- Sorbonne University, Paris Brain Institute - ICM, Inserm, CNRS, AP-HP, Paris, France
| | - Eric Leguern
- Sorbonne University, Paris Brain Institute - ICM, Inserm, CNRS, AP-HP, Paris, France
- Genetics Department, APHP, Pitié-Salpêtrière Hospital, Paris, France
| | - Laura P W Ranum
- Center for NeuroGenetics, College of Medicine, University of Florida, Gainesville, FL, USA
| | - António Amorim
- i3S-Instituto de Investigação e Inovação em Saúde, University of Porto, Porto, Portugal
- IPATIMUP-Institute of Molecular Pathology and Immunology, University of Porto, Porto, Portugal
- Department of Biology, Faculty of Sciences, University of Porto, Porto, Portugal
| | - Liena E O Elsayed
- Department of Basic Sciences, College of Medicine, Princess Nourah bint Abdulrahman University, Riyadh, Saudi Arabia
| | - Giovanni Stevanin
- Sorbonne University, Paris Brain Institute - ICM, Inserm, CNRS, AP-HP, Paris, France
- Univ. Bordeaux, CNRS-Centre National de la Recherche Scientifique, INCIA-Institut de Neurosciences Cognitives et Intégratives d'Aquitaine, UMR 5287, Bordeaux, France
- EPHE-École Pratique des Hautes Études, CNRS-Centre National de la Recherche Scientifique, INCIA-Institut de Neurosciences Cognitives et Intégratives d'Aquitaine, UMR 5287, Paris, France
| | - Jorge Sequeiros
- i3S-Instituto de Investigação e Inovação em Saúde, University of Porto, Porto, Portugal.
- UnIGENe and CGPP-Centro de Genética Preditiva e Preventiva, IBMC-Institute for Molecular and Cell Biology, University of Porto, Porto, Portugal.
- ICBAS School of Medicine and Biomedical Sciences, University of Porto, Porto, Portugal.
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3
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Nutter CA, Kidd BM, Carter HA, Hamel JI, Mackie PM, Kumbkarni N, Davenport ML, Tuyn DM, Gopinath A, Creigh PD, Sznajder ŁJ, Wang ET, Ranum LPW, Khoshbouei H, Day JW, Sampson JB, Prokop S, Swanson MS. Choroid plexus mis-splicing and altered cerebrospinal fluid composition in myotonic dystrophy type 1. Brain 2023; 146:4217-4232. [PMID: 37143315 PMCID: PMC10545633 DOI: 10.1093/brain/awad148] [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: 01/23/2023] [Revised: 04/08/2023] [Accepted: 04/18/2023] [Indexed: 05/06/2023] Open
Abstract
Myotonic dystrophy type 1 is a dominantly inherited multisystemic disease caused by CTG tandem repeat expansions in the DMPK 3' untranslated region. These expanded repeats are transcribed and produce toxic CUG RNAs that sequester and inhibit activities of the MBNL family of developmental RNA processing factors. Although myotonic dystrophy is classified as a muscular dystrophy, the brain is also severely affected by an unusual cohort of symptoms, including hypersomnia, executive dysfunction, as well as early onsets of tau/MAPT pathology and cerebral atrophy. To address the molecular and cellular events that lead to these pathological outcomes, we recently generated a mouse Dmpk CTG expansion knock-in model and identified choroid plexus epithelial cells as particularly affected by the expression of toxic CUG expansion RNAs. To determine if toxic CUG RNAs perturb choroid plexus functions, alternative splicing analysis was performed on lateral and hindbrain choroid plexi from Dmpk CTG knock-in mice. Choroid plexus transcriptome-wide changes were evaluated in Mbnl2 knockout mice, a developmental-onset model of myotonic dystrophy brain dysfunction. To determine if transcriptome changes also occurred in the human disease, we obtained post-mortem choroid plexus for RNA-seq from neurologically unaffected (two females, three males; ages 50-70 years) and myotonic dystrophy type 1 (one female, three males; ages 50-70 years) donors. To test that choroid plexus transcriptome alterations resulted in altered CSF composition, we obtained CSF via lumbar puncture from patients with myotonic dystrophy type 1 (five females, five males; ages 35-55 years) and non-myotonic dystrophy patients (three females, four males; ages 26-51 years), and western blot and osmolarity analyses were used to test CSF alterations predicted by choroid plexus transcriptome analysis. We determined that CUG RNA induced toxicity was more robust in the lateral choroid plexus of Dmpk CTG knock-in mice due to comparatively higher Dmpk and lower Mbnl RNA levels. Impaired transitions to adult splicing patterns during choroid plexus development were identified in Mbnl2 knockout mice, including mis-splicing previously found in Dmpk CTG knock-in mice. Whole transcriptome analysis of myotonic dystrophy type 1 choroid plexus revealed disease-associated RNA expression and mis-splicing events. Based on these RNA changes, predicted alterations in ion homeostasis, secretory output and CSF composition were confirmed by analysis of myotonic dystrophy type 1 CSF. Our results implicate choroid plexus spliceopathy and concomitant alterations in CSF homeostasis as an unappreciated contributor to myotonic dystrophy type 1 CNS pathogenesis.
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Affiliation(s)
- Curtis A Nutter
- Department of Molecular Genetics and Microbiology, Center for NeuroGenetics and the Genetics Institute, University of Florida, College of Medicine, Gainesville, FL 32610, USA
| | - Benjamin M Kidd
- Department of Molecular Genetics and Microbiology, Center for NeuroGenetics and the Genetics Institute, University of Florida, College of Medicine, Gainesville, FL 32610, USA
| | - Helmut A Carter
- Department of Molecular Genetics and Microbiology, Center for NeuroGenetics and the Genetics Institute, University of Florida, College of Medicine, Gainesville, FL 32610, USA
| | - Johanna I Hamel
- Department of Neurology, University of Rochester, Rochester, NY 14642, USA
| | - Philip M Mackie
- Department of Neuroscience, McKnight Brain Institute, College of Medicine, University of Florida, Gainesville, FL 32610, USA
| | - Nayha Kumbkarni
- Department of Molecular Genetics and Microbiology, Center for NeuroGenetics and the Genetics Institute, University of Florida, College of Medicine, Gainesville, FL 32610, USA
| | - Mackenzie L Davenport
- Department of Molecular Genetics and Microbiology, Center for NeuroGenetics and the Genetics Institute, University of Florida, College of Medicine, Gainesville, FL 32610, USA
| | - Dana M Tuyn
- Department of Molecular Genetics and Microbiology, Center for NeuroGenetics and the Genetics Institute, University of Florida, College of Medicine, Gainesville, FL 32610, USA
| | - Adithya Gopinath
- Department of Neuroscience, McKnight Brain Institute, College of Medicine, University of Florida, Gainesville, FL 32610, USA
| | - Peter D Creigh
- Department of Neurology, University of Rochester, Rochester, NY 14642, USA
| | - Łukasz J Sznajder
- Department of Molecular Genetics and Microbiology, Center for NeuroGenetics and the Genetics Institute, University of Florida, College of Medicine, Gainesville, FL 32610, USA
| | - Eric T Wang
- Department of Molecular Genetics and Microbiology, Center for NeuroGenetics and the Genetics Institute, University of Florida, College of Medicine, Gainesville, FL 32610, USA
| | - Laura P W Ranum
- Department of Molecular Genetics and Microbiology, Center for NeuroGenetics and the Genetics Institute, McKnight Brain Institute and the Fixel Institute for Neurological Diseases, College of Medicine, University of Florida, Gainesville, FL 32610, USA
| | - Habibeh Khoshbouei
- Department of Neuroscience, McKnight Brain Institute, College of Medicine, University of Florida, Gainesville, FL 32610, USA
| | - John W Day
- Department of Neurology and Neurological Sciences, Stanford University School of Medicine, Stanford, CA 94304, USA
| | - Jacinda B Sampson
- Department of Neurology and Neurological Sciences, Stanford University School of Medicine, Stanford, CA 94304, USA
| | - Stefan Prokop
- Department of Pathology, Immunology, and Laboratory Medicine, Center for Translational Research in Neurodegenerative Disease, McKnight Brain Institute and the Fixel Institute for Neurological Diseases, College of Medicine, University of Florida, Gainesville, FL 32610, USA
| | - Maurice S Swanson
- Department of Molecular Genetics and Microbiology, Center for NeuroGenetics and the Genetics Institute, University of Florida, College of Medicine, Gainesville, FL 32610, USA
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4
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Paul S, Dansithong W, Gandelman M, Figueroa KP, Zu T, Ranum LPW, Scoles DR, Pulst SM. Staufen Impairs Autophagy in Neurodegeneration. Ann Neurol 2023; 93:398-416. [PMID: 36151701 PMCID: PMC9892312 DOI: 10.1002/ana.26515] [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] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2022] [Revised: 09/20/2022] [Accepted: 09/22/2022] [Indexed: 02/04/2023]
Abstract
OBJECTIVE The mechanistic target of rapamycin (mTOR) kinase is one of the master coordinators of cellular stress responses, regulating metabolism, autophagy, and apoptosis. We recently reported that staufen1 (STAU1), a stress granule (SG) protein, was overabundant in fibroblast cell lines from patients with spinocerebellar ataxia type 2 (SCA2), amyotrophic lateral sclerosis, frontotemporal degeneration, Huntington's, Alzheimer's, and Parkinson's diseases as well as animal models, and patient tissues. STAU1 overabundance is associated with mTOR hyperactivation and links SG formation with autophagy. Our objective was to determine the mechanism of mTOR regulation by STAU1. METHODS We determined STAU1 abundance with disease- and chemical-induced cellular stressors in patient cells and animal models. We also used RNA-binding assays to contextualize STAU1 interaction with MTOR mRNA. RESULTS STAU1 and mTOR were overabundant in bacterial artificial chromosome (BAC)-C9ORF72, ATXN2Q127 , and Thy1-TDP-43 transgenic mouse models. Reducing STAU1 levels in these mice normalized mTOR levels and activity and autophagy-related marker proteins. We also saw increased STAU1 levels in HEK293 cells transfected to express C9ORF72-relevant dipeptide repeats (DPRs). Conversely, DPR accumulations were not observed in cells treated by STAU1 RNA interference (RNAi). Overexpression of STAU1 in HEK293 cells increased mTOR levels through direct MTOR mRNA interaction, activating downstream targets and impairing autophagic flux. Targeting mTOR by rapamycin or RNAi normalized STAU1 abundance in an SCA2 cellular model. INTERPRETATION STAU1 interaction with mTOR drives its hyperactivation and inhibits autophagic flux in multiple models of neurodegeneration. Staufen, therefore, constitutes a novel target to modulate mTOR activity and autophagy, and for the treatment of neurodegenerative diseases. ANN NEUROL 2023;93:398-416.
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Affiliation(s)
- Sharan Paul
- Department of Neurology, University of Utah, Salt Lake City, UT
| | | | - Mandi Gandelman
- Department of Neurology, University of Utah, Salt Lake City, UT
| | | | - Tao Zu
- Center for NeuroGenetics and Department of Molecular Genetics and Microbiology, University of Florida, Gainesville, FL
| | - Laura P W Ranum
- Center for NeuroGenetics and Department of Molecular Genetics and Microbiology, University of Florida, Gainesville, FL
| | - Daniel R Scoles
- Department of Neurology, University of Utah, Salt Lake City, UT
| | - Stefan M Pulst
- Department of Neurology, University of Utah, Salt Lake City, UT
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5
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Gu X, Richman J, Langfelder P, Wang N, Zhang S, Bañez-Coronel M, Wang HB, Yang L, Ramanathan L, Deng L, Park CS, Choi CR, Cantle JP, Gao F, Gray M, Coppola G, Bates GP, Ranum LPW, Horvath S, Colwell CS, Yang XW. Uninterrupted CAG repeat drives striatum-selective transcriptionopathy and nuclear pathogenesis in human Huntingtin BAC mice. Neuron 2022; 110:1173-1192.e7. [PMID: 35114102 PMCID: PMC9462388 DOI: 10.1016/j.neuron.2022.01.006] [Citation(s) in RCA: 21] [Impact Index Per Article: 10.5] [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: 07/04/2020] [Revised: 10/30/2021] [Accepted: 01/06/2022] [Indexed: 02/08/2023]
Abstract
In Huntington's disease (HD), the uninterrupted CAG repeat length, but not the polyglutamine length, predicts disease onset. However, the underlying pathobiology remains unclear. Here, we developed bacterial artificial chromosome (BAC) transgenic mice expressing human mutant huntingtin (mHTT) with uninterrupted, and somatically unstable, CAG repeats that exhibit progressive disease-related phenotypes. Unlike prior mHTT transgenic models with stable, CAA-interrupted, polyglutamine-encoding repeats, BAC-CAG mice show robust striatum-selective nuclear inclusions and transcriptional dysregulation resembling those in murine huntingtin knockin models and HD patients. Importantly, the striatal transcriptionopathy in HD models is significantly correlated with their uninterrupted CAG repeat length but not polyglutamine length. Finally, among the pathogenic entities originating from mHTT genomic transgenes and only present or enriched in the uninterrupted CAG repeat model, somatic CAG repeat instability and nuclear mHTT aggregation are best correlated with early-onset striatum-selective molecular pathogenesis and locomotor and sleep deficits, while repeat RNA-associated pathologies and repeat-associated non-AUG (RAN) translation may play less selective or late pathogenic roles, respectively.
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Affiliation(s)
- Xiaofeng Gu
- Center for Neurobehavioral Genetics, Jane and Terry Semel Institute of Neuroscience and Human Behavior, University of California, Los Angeles, Los Angeles, CA, USA; Department Psychiatry and Biobehavioral Science, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA, USA
| | - Jeffrey Richman
- Center for Neurobehavioral Genetics, Jane and Terry Semel Institute of Neuroscience and Human Behavior, University of California, Los Angeles, Los Angeles, CA, USA; Department Psychiatry and Biobehavioral Science, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA, USA
| | - Peter Langfelder
- Center for Neurobehavioral Genetics, Jane and Terry Semel Institute of Neuroscience and Human Behavior, University of California, Los Angeles, Los Angeles, CA, USA; Department Psychiatry and Biobehavioral Science, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA, USA
| | - Nan Wang
- Center for Neurobehavioral Genetics, Jane and Terry Semel Institute of Neuroscience and Human Behavior, University of California, Los Angeles, Los Angeles, CA, USA; Department Psychiatry and Biobehavioral Science, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA, USA
| | - Shasha Zhang
- Center for Neurobehavioral Genetics, Jane and Terry Semel Institute of Neuroscience and Human Behavior, University of California, Los Angeles, Los Angeles, CA, USA; Department Psychiatry and Biobehavioral Science, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA, USA
| | - Monica Bañez-Coronel
- Center for Neurogenetics, Department of Molecular Genetics and Microbiology, College of Medicine, Genetics Institute, McKnight Brain Institute, Norman Fixel Institute of Neurological Diseases, University of Florida, Gainesville, FL, USA
| | - Huei-Bin Wang
- Department Psychiatry and Biobehavioral Science, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA, USA
| | - Lucia Yang
- Center for Neurobehavioral Genetics, Jane and Terry Semel Institute of Neuroscience and Human Behavior, University of California, Los Angeles, Los Angeles, CA, USA; Department Psychiatry and Biobehavioral Science, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA, USA
| | - Lalini Ramanathan
- Center for Neurobehavioral Genetics, Jane and Terry Semel Institute of Neuroscience and Human Behavior, University of California, Los Angeles, Los Angeles, CA, USA; Department Psychiatry and Biobehavioral Science, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA, USA
| | - Linna Deng
- Center for Neurobehavioral Genetics, Jane and Terry Semel Institute of Neuroscience and Human Behavior, University of California, Los Angeles, Los Angeles, CA, USA; Department Psychiatry and Biobehavioral Science, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA, USA
| | - Chang Sin Park
- Center for Neurobehavioral Genetics, Jane and Terry Semel Institute of Neuroscience and Human Behavior, University of California, Los Angeles, Los Angeles, CA, USA; Department Psychiatry and Biobehavioral Science, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA, USA
| | - Christopher R Choi
- Center for Neurobehavioral Genetics, Jane and Terry Semel Institute of Neuroscience and Human Behavior, University of California, Los Angeles, Los Angeles, CA, USA; Department Psychiatry and Biobehavioral Science, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA, USA
| | - Jeffrey P Cantle
- Center for Neurobehavioral Genetics, Jane and Terry Semel Institute of Neuroscience and Human Behavior, University of California, Los Angeles, Los Angeles, CA, USA; Department Psychiatry and Biobehavioral Science, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA, USA
| | - Fuying Gao
- Center for Neurobehavioral Genetics, Jane and Terry Semel Institute of Neuroscience and Human Behavior, University of California, Los Angeles, Los Angeles, CA, USA; Department Psychiatry and Biobehavioral Science, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA, USA
| | - Michelle Gray
- Department of Neurology and Center for Neurodegeneration and Experimental Therapeutics, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Giovanni Coppola
- Center for Neurobehavioral Genetics, Jane and Terry Semel Institute of Neuroscience and Human Behavior, University of California, Los Angeles, Los Angeles, CA, USA; Department Psychiatry and Biobehavioral Science, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA, USA
| | - Gillian P Bates
- Huntington's Disease Centre, Sobell Department of Motor Neuroscience and Movement Disorders, UCL Queen Square Institute of Neurology, University College London, London, United Kingdom
| | - Laura P W Ranum
- Center for Neurogenetics, Department of Molecular Genetics and Microbiology, College of Medicine, Genetics Institute, McKnight Brain Institute, Norman Fixel Institute of Neurological Diseases, University of Florida, Gainesville, FL, USA
| | - Steve Horvath
- Department of Human Genetics, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA, USA
| | - Christopher S Colwell
- Department Psychiatry and Biobehavioral Science, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA, USA
| | - X William Yang
- Center for Neurobehavioral Genetics, Jane and Terry Semel Institute of Neuroscience and Human Behavior, University of California, Los Angeles, Los Angeles, CA, USA; Department Psychiatry and Biobehavioral Science, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA, USA.
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6
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Guo S, Nguyen L, Ranum LPW. RAN proteins in neurodegenerative disease: Repeating themes and unifying therapeutic strategies. Curr Opin Neurobiol 2021; 72:160-170. [PMID: 34953315 DOI: 10.1016/j.conb.2021.11.001] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2021] [Revised: 11/01/2021] [Accepted: 11/02/2021] [Indexed: 11/29/2022]
Abstract
Microsatellite-expansion mutations cause >50 neurological diseases but there are no effective treatments. Mechanistic studies have historically focused on protein loss-of-function and protein or RNA gain-of-function effects. It is now clear that many expansion mutations are bidirectionally transcribed producing two toxic expansion RNAs, which can produce up to six mutant proteins by repeat associated non-AUG (RAN) translation. Multiple types of RAN proteins have been shown to be toxic in cell and animal models, to lead to common types of neuropathological changes, and to dysregulate key pathways. How RAN proteins are produced without the canonical AUG or close-cognate AUG-like initiation codons is not yet completely understood but RNA structure, flanking sequences and stress pathways have been shown to be important. Here, we summarize recent progress in understanding the role of RAN proteins, mechanistic insights into their production, and the identification of novel therapeutic strategies that may be applicable across these neurodegenerative disorders.
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Affiliation(s)
- Shu Guo
- Center for NeuroGenetics, College of Medicine, University of Florida, USA; Department of Molecular Genetics and Microbiology, College of Medicine, University of Florida, USA
| | - Lien Nguyen
- Center for NeuroGenetics, College of Medicine, University of Florida, USA; Department of Molecular Genetics and Microbiology, College of Medicine, University of Florida, USA.
| | - Laura P W Ranum
- Center for NeuroGenetics, College of Medicine, University of Florida, USA; Department of Molecular Genetics and Microbiology, College of Medicine, University of Florida, USA; Genetics Institute, University of Florida, USA; McKnight Brain Institute, University of Florida, USA; Norman Fixel Institute for Neurological Diseases, University of Florida, USA.
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7
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Tusi SK, Nguyen L, Thangaraju K, Li J, Cleary JD, Zu T, Ranum LPW. The alternative initiation factor eIF2A plays key role in RAN translation of myotonic dystrophy type 2 CCUG•CAGG repeats. Hum Mol Genet 2021; 30:1020-1029. [PMID: 33856033 DOI: 10.1093/hmg/ddab098] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2020] [Revised: 03/26/2021] [Accepted: 03/31/2021] [Indexed: 01/29/2023] Open
Abstract
Repeat-associated non-ATG (RAN) proteins have been reported in 11 microsatellite expansion disorders but the factors that allow RAN translation to occur and the effects of different repeat motifs and alternative AUG-like initiation codons are unclear. We studied the mechanisms of RAN translation across myotonic dystrophy type 2 (DM2) expansion transcripts with (CCUG) or without (CAGG) efficient alternative AUG-like codons. To better understand how DM2 LPAC and QAGR RAN proteins are expressed, we generated a series of CRISPR/Cas9-edited HEK293T cell lines. We show that LPAC and QAGR RAN protein levels are reduced in protein kinase R (PKR)-/- and PKR-like endoplasmic reticulum kinase (PERK)-/- cells, with more substantial reductions of CAGG-encoded QAGR in PKR-/- cells. Experiments using mutant eIF2α-S51A HEK293T cells show that p-eIF2α is required for QAGR production. In contrast, LPAC levels were only partially reduced in these cells, suggesting that both non-AUG and close-cognate initiation occur across CCUG RNAs. Overexpression of the alternative initiation factor eIF2A increases LPAC and QAGR protein levels but, notably, has a much larger effect on QAGR expressed from CAGG-expansion RNAs that lack efficient close-cognate codons. The effects of eIF2A on increasing LPAC are consistent with previous reports that eIF2A affects CUG-initiation translation. The observation that eIF2A also increases QAGR proteins is novel because CAGG expansion transcripts do not contain CUG or similarly efficient close-cognate AUG-like codons. For QAGR but not LPAC, the eIF2A-dependent increases are not seen when p-eIF2α is blocked. These data highlight the differential regulation of DM2 RAN proteins and eIF2A as a potential therapeutic target for DM2 and other RAN diseases.
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Affiliation(s)
- Solaleh Khoramian Tusi
- Center for NeuroGenetics, College of Medicine, University of Florida, Gainesville, FL 32610, USA
- Department of Molecular Genetics and Microbiology, College of Medicine, University of Florida, Gainesville, FL 32610, USA
- Genetics Institute, University of Florida, Gainesville, FL 32610, USA
| | - Lien Nguyen
- Center for NeuroGenetics, College of Medicine, University of Florida, Gainesville, FL 32610, USA
- Department of Molecular Genetics and Microbiology, College of Medicine, University of Florida, Gainesville, FL 32610, USA
- Genetics Institute, University of Florida, Gainesville, FL 32610, USA
| | - Kiruphagaran Thangaraju
- Center for NeuroGenetics, College of Medicine, University of Florida, Gainesville, FL 32610, USA
- Department of Molecular Genetics and Microbiology, College of Medicine, University of Florida, Gainesville, FL 32610, USA
- Genetics Institute, University of Florida, Gainesville, FL 32610, USA
| | - Jian Li
- Center for NeuroGenetics, College of Medicine, University of Florida, Gainesville, FL 32610, USA
- Department of Molecular Genetics and Microbiology, College of Medicine, University of Florida, Gainesville, FL 32610, USA
- Genetics Institute, University of Florida, Gainesville, FL 32610, USA
| | - John D Cleary
- Center for NeuroGenetics, College of Medicine, University of Florida, Gainesville, FL 32610, USA
- Department of Molecular Genetics and Microbiology, College of Medicine, University of Florida, Gainesville, FL 32610, USA
- Genetics Institute, University of Florida, Gainesville, FL 32610, USA
| | - Tao Zu
- Center for NeuroGenetics, College of Medicine, University of Florida, Gainesville, FL 32610, USA
- Department of Molecular Genetics and Microbiology, College of Medicine, University of Florida, Gainesville, FL 32610, USA
- Genetics Institute, University of Florida, Gainesville, FL 32610, USA
| | - Laura P W Ranum
- Center for NeuroGenetics, College of Medicine, University of Florida, Gainesville, FL 32610, USA
- Department of Molecular Genetics and Microbiology, College of Medicine, University of Florida, Gainesville, FL 32610, USA
- Genetics Institute, University of Florida, Gainesville, FL 32610, USA
- McKnight Brain Institute, University of Florida, Gainesville, FL 32610, USA
- Norman Fixel Institute for Neurological Diseases, University of Florida, Gainesville, FL 32610, USA
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8
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Pattamatta A, Nguyen L, Olafson HR, Scotti MM, Laboissonniere LA, Richardson J, Berglund JA, Zu T, Wang ET, Ranum LPW. Repeat length increases disease penetrance and severity in C9orf72 ALS/FTD BAC transgenic mice. Hum Mol Genet 2020; 29:3900-3918. [PMID: 33378537 DOI: 10.1093/hmg/ddaa279] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2020] [Revised: 11/14/2020] [Accepted: 12/23/2020] [Indexed: 12/12/2022] Open
Abstract
C9orf72 ALS/FTD patients show remarkable clinical heterogeneity, but the complex biology of the repeat expansion mutation has limited our understanding of the disease. BAC transgenic mice were used to better understand the molecular mechanisms and repeat length effects of C9orf72 ALS/FTD. Genetic analyses of these mice demonstrate that the BAC transgene and not integration site effects cause ALS/FTD phenotypes. Transcriptomic changes in cell proliferation, inflammation and neuronal pathways are found late in disease and alternative splicing changes provide early molecular markers that worsen with disease progression. Isogenic sublines of mice with 800, 500 or 50 G4C2 repeats generated from the single-copy C9-500 line show longer repeats result in earlier onset, increased disease penetrance and increased levels of RNA foci and dipeptide RAN protein aggregates. These data demonstrate G4C2 repeat length is an important driver of disease and identify alternative splicing changes as early biomarkers of C9orf72 ALS/FTD.
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Affiliation(s)
- Amrutha Pattamatta
- Center for NeuroGenetics, Colllege of Medicine, University of Florida, Gainesville, FL 32610, USA.,Department of Molecular Genetics and Microbiology, Colllege of Medicine, University of Florida, Gainesville, FL 32610, USA.,University of Florida Genetics Institute, University of Florida, Gainesville, FL 32610, USA
| | - Lien Nguyen
- Center for NeuroGenetics, Colllege of Medicine, University of Florida, Gainesville, FL 32610, USA.,Department of Molecular Genetics and Microbiology, Colllege of Medicine, University of Florida, Gainesville, FL 32610, USA.,University of Florida Genetics Institute, University of Florida, Gainesville, FL 32610, USA
| | - Hailey R Olafson
- Center for NeuroGenetics, Colllege of Medicine, University of Florida, Gainesville, FL 32610, USA.,Department of Molecular Genetics and Microbiology, Colllege of Medicine, University of Florida, Gainesville, FL 32610, USA.,University of Florida Genetics Institute, University of Florida, Gainesville, FL 32610, USA
| | - Marina M Scotti
- Center for NeuroGenetics, Colllege of Medicine, University of Florida, Gainesville, FL 32610, USA.,Department of Molecular Genetics and Microbiology, Colllege of Medicine, University of Florida, Gainesville, FL 32610, USA.,University of Florida Genetics Institute, University of Florida, Gainesville, FL 32610, USA
| | - Lauren A Laboissonniere
- Center for NeuroGenetics, Colllege of Medicine, University of Florida, Gainesville, FL 32610, USA.,Department of Molecular Genetics and Microbiology, Colllege of Medicine, University of Florida, Gainesville, FL 32610, USA.,University of Florida Genetics Institute, University of Florida, Gainesville, FL 32610, USA
| | - Jared Richardson
- Center for NeuroGenetics, Colllege of Medicine, University of Florida, Gainesville, FL 32610, USA.,University of Florida Genetics Institute, University of Florida, Gainesville, FL 32610, USA.,McKnight Brain Institute, University of Florida, Gainesville, FL 32610, USA
| | - J Andrew Berglund
- Center for NeuroGenetics, Colllege of Medicine, University of Florida, Gainesville, FL 32610, USA.,Department of Biochemistry and Molecular Biology, Colllege of Medicine, University of Florida, Gainesville, FL 32610, USA.,RNA Institute and Department of Biological Sciences, University at Albany, Albany, NY 12222, USA
| | - Tao Zu
- Center for NeuroGenetics, Colllege of Medicine, University of Florida, Gainesville, FL 32610, USA.,Department of Molecular Genetics and Microbiology, Colllege of Medicine, University of Florida, Gainesville, FL 32610, USA.,University of Florida Genetics Institute, University of Florida, Gainesville, FL 32610, USA
| | - Eric T Wang
- Center for NeuroGenetics, Colllege of Medicine, University of Florida, Gainesville, FL 32610, USA.,Department of Molecular Genetics and Microbiology, Colllege of Medicine, University of Florida, Gainesville, FL 32610, USA.,University of Florida Genetics Institute, University of Florida, Gainesville, FL 32610, USA.,McKnight Brain Institute, University of Florida, Gainesville, FL 32610, USA
| | - Laura P W Ranum
- Center for NeuroGenetics, Colllege of Medicine, University of Florida, Gainesville, FL 32610, USA.,Department of Molecular Genetics and Microbiology, Colllege of Medicine, University of Florida, Gainesville, FL 32610, USA.,University of Florida Genetics Institute, University of Florida, Gainesville, FL 32610, USA.,McKnight Brain Institute, University of Florida, Gainesville, FL 32610, USA.,Fixel Institute, University of Florida, Gainesville, FL 32610, USA
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9
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Sznajder ŁJ, Scotti MM, Shin J, Taylor K, Ivankovic F, Nutter CA, Aslam FN, Subramony SH, Ranum LPW, Swanson MS. Loss of MBNL1 induces RNA misprocessing in the thymus and peripheral blood. Nat Commun 2020; 11:2022. [PMID: 32332745 PMCID: PMC7181699 DOI: 10.1038/s41467-020-15962-x] [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] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2019] [Accepted: 04/03/2020] [Indexed: 12/25/2022] Open
Abstract
The thymus is a primary lymphoid organ that plays an essential role in T lymphocyte maturation and selection during development of one arm of the mammalian adaptive immune response. Although transcriptional mechanisms have been well documented in thymocyte development, co-/post-transcriptional modifications are also important but have received less attention. Here we demonstrate that the RNA alternative splicing factor MBNL1, which is sequestered in nuclear RNA foci by C(C)UG microsatellite expansions in myotonic dystrophy (DM), is essential for normal thymus development and function. Mbnl1 129S1 knockout mice develop postnatal thymic hyperplasia with thymocyte accumulation. Transcriptome analysis indicates numerous gene expression and RNA mis-splicing events, including transcription factors from the TCF/LEF family. CNBP, the gene containing an intronic CCTG microsatellite expansion in DM type 2 (DM2), is coordinately expressed with MBNL1 in the developing thymus and DM2 CCTG expansions induce similar transcriptome alterations in DM2 blood, which thus serve as disease-specific biomarkers.
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Affiliation(s)
- Łukasz J Sznajder
- Department of Molecular Genetics and Microbiology, Center for NeuroGenetics and the Genetics Institute, University of Florida, College of Medicine, Gainesville, FL, 32610, USA.
| | - Marina M Scotti
- Department of Molecular Genetics and Microbiology, Center for NeuroGenetics and the Genetics Institute, University of Florida, College of Medicine, Gainesville, FL, 32610, USA
| | - Jihae Shin
- Department of Molecular Genetics and Microbiology, Center for NeuroGenetics and the Genetics Institute, University of Florida, College of Medicine, Gainesville, FL, 32610, USA.,Department of Microbiology, Biochemistry and Molecular Genetics, Rutgers New Jersey Medical School and Rutgers Cancer Institute of New Jersey, Newark, NJ, 07103, USA
| | - Katarzyna Taylor
- Department of Molecular Genetics and Microbiology, Center for NeuroGenetics and the Genetics Institute, University of Florida, College of Medicine, Gainesville, FL, 32610, USA.,Laboratory of Gene Therapy, Department of Gene Expression, Institute of Molecular Biology and Biotechnology, Faculty of Biology, Adam Mickiewicz University, Umultowska 89, 61-614 Poznań, Poland
| | - Franjo Ivankovic
- Department of Molecular Genetics and Microbiology, Center for NeuroGenetics and the Genetics Institute, University of Florida, College of Medicine, Gainesville, FL, 32610, USA
| | - Curtis A Nutter
- Department of Molecular Genetics and Microbiology, Center for NeuroGenetics and the Genetics Institute, University of Florida, College of Medicine, Gainesville, FL, 32610, USA
| | - Faaiq N Aslam
- Department of Molecular Genetics and Microbiology, Center for NeuroGenetics and the Genetics Institute, University of Florida, College of Medicine, Gainesville, FL, 32610, USA
| | - S H Subramony
- Department of Neurology, Center for NeuroGenetics, University of Florida, College of Medicine, Gainesville, FL, 32610, USA
| | - Laura P W Ranum
- Department of Molecular Genetics and Microbiology, Center for NeuroGenetics and the Genetics Institute, University of Florida, College of Medicine, Gainesville, FL, 32610, USA
| | - Maurice S Swanson
- Department of Molecular Genetics and Microbiology, Center for NeuroGenetics and the Genetics Institute, University of Florida, College of Medicine, Gainesville, FL, 32610, USA.
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10
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Nguyen L, Montrasio F, Pattamatta A, Tusi SK, Bardhi O, Meyer KD, Hayes L, Nakamura K, Banez-Coronel M, Coyne A, Guo S, Laboissonniere LA, Gu Y, Narayanan S, Smith B, Nitsch RM, Kankel MW, Rushe M, Rothstein J, Zu T, Grimm J, Ranum LPW. Antibody Therapy Targeting RAN Proteins Rescues C9 ALS/FTD Phenotypes in C9orf72 Mouse Model. Neuron 2019; 105:645-662.e11. [PMID: 31831332 DOI: 10.1016/j.neuron.2019.11.007] [Citation(s) in RCA: 36] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2019] [Revised: 10/10/2019] [Accepted: 11/05/2019] [Indexed: 10/25/2022]
Abstract
The intronic C9orf72 G4C2 expansion, the most common genetic cause of ALS and FTD, produces sense- and antisense-expansion RNAs and six dipeptide repeat-associated, non-ATG (RAN) proteins, but their roles in disease are unclear. We generated high-affinity human antibodies targeting GA or GP RAN proteins. These antibodies cross the blood-brain barrier and co-localize with intracellular RAN aggregates in C9-ALS/FTD BAC mice. In cells, α-GA1 interacts with TRIM21, and α-GA1 treatment reduced GA levels, increased GA turnover, and decreased RAN toxicity and co-aggregation of proteasome and autophagy proteins to GA aggregates. In C9-BAC mice, α-GA1 reduced GA as well as GP and GR proteins, improved behavioral deficits, decreased neuroinflammation and neurodegeneration, and increased survival. Glycosylation of the Fc region of α-GA1 is important for cell entry and efficacy. These data demonstrate that RAN proteins drive C9-ALS/FTD in C9-BAC transgenic mice and establish a novel therapeutic approach for C9orf72 ALS/FTD and other RAN-protein diseases.
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Affiliation(s)
- Lien Nguyen
- Center for NeuroGenetics, Department of Molecular Genetics and Microbiology, Genetics Institute, McKnight Brain Institute, Norman Fixel Institute for Neurological Diseases, University of Florida, Gainesville, FL 32610, USA
| | | | - Amrutha Pattamatta
- Center for NeuroGenetics, Department of Molecular Genetics and Microbiology, Genetics Institute, McKnight Brain Institute, Norman Fixel Institute for Neurological Diseases, University of Florida, Gainesville, FL 32610, USA
| | - Solaleh Khoramian Tusi
- Center for NeuroGenetics, Department of Molecular Genetics and Microbiology, Genetics Institute, McKnight Brain Institute, Norman Fixel Institute for Neurological Diseases, University of Florida, Gainesville, FL 32610, USA
| | - Olgert Bardhi
- Center for NeuroGenetics, Department of Molecular Genetics and Microbiology, Genetics Institute, McKnight Brain Institute, Norman Fixel Institute for Neurological Diseases, University of Florida, Gainesville, FL 32610, USA
| | - Kevin D Meyer
- Neurimmune AG, 8952 Schlieren, Switzerland; Institute for Regenerative Medicine-IREM, University of Zurich, 8952 Schlieren, Switzerland
| | - Lindsey Hayes
- Department of Neurology, Johns Hopkins University, Baltimore, MD 21205, USA
| | - Katsuya Nakamura
- Center for NeuroGenetics, Department of Molecular Genetics and Microbiology, Genetics Institute, McKnight Brain Institute, Norman Fixel Institute for Neurological Diseases, University of Florida, Gainesville, FL 32610, USA
| | - Monica Banez-Coronel
- Center for NeuroGenetics, Department of Molecular Genetics and Microbiology, Genetics Institute, McKnight Brain Institute, Norman Fixel Institute for Neurological Diseases, University of Florida, Gainesville, FL 32610, USA
| | - Alyssa Coyne
- Department of Neurology, Johns Hopkins University, Baltimore, MD 21205, USA
| | - Shu Guo
- Center for NeuroGenetics, Department of Molecular Genetics and Microbiology, Genetics Institute, McKnight Brain Institute, Norman Fixel Institute for Neurological Diseases, University of Florida, Gainesville, FL 32610, USA
| | - Lauren A Laboissonniere
- Center for NeuroGenetics, Department of Molecular Genetics and Microbiology, Genetics Institute, McKnight Brain Institute, Norman Fixel Institute for Neurological Diseases, University of Florida, Gainesville, FL 32610, USA
| | - Yuanzheng Gu
- Neuromuscular and Movement Disorders, Biogen, Cambridge, MA 02142, USA
| | | | - Benjamin Smith
- Neuromuscular and Movement Disorders, Biogen, Cambridge, MA 02142, USA
| | - Roger M Nitsch
- Neurimmune AG, 8952 Schlieren, Switzerland; Institute for Regenerative Medicine-IREM, University of Zurich, 8952 Schlieren, Switzerland
| | - Mark W Kankel
- Neuromuscular and Movement Disorders, Biogen, Cambridge, MA 02142, USA
| | - Mia Rushe
- Neuromuscular and Movement Disorders, Biogen, Cambridge, MA 02142, USA
| | - Jeffrey Rothstein
- Department of Neurology, Johns Hopkins University, Baltimore, MD 21205, USA
| | - Tao Zu
- Center for NeuroGenetics, Department of Molecular Genetics and Microbiology, Genetics Institute, McKnight Brain Institute, Norman Fixel Institute for Neurological Diseases, University of Florida, Gainesville, FL 32610, USA
| | - Jan Grimm
- Neurimmune AG, 8952 Schlieren, Switzerland
| | - Laura P W Ranum
- Center for NeuroGenetics, Department of Molecular Genetics and Microbiology, Genetics Institute, McKnight Brain Institute, Norman Fixel Institute for Neurological Diseases, University of Florida, Gainesville, FL 32610, USA.
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11
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Abstract
More than 40 different neurological diseases are caused by microsatellite repeat expansions. Since the discovery of repeat-associated non-AUG (RAN) translation by Zu et al. in 2011, nine expansion disorders have been identified as RAN-positive diseases. RAN proteins are translated from different types of nucleotide repeat expansions and can be produced from both sense and antisense transcripts. In some diseases, RAN proteins have been shown to accumulate in affected brain regions. Here we review the pathological and molecular aspects associated with RAN protein accumulation for each particular disorder, the correlation between disease pathology and the available in vivo models and the common aspects shared by some of the newly discovered RAN proteins.
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Affiliation(s)
- Monica Banez-Coronel
- Center for NeuroGenetics, University of Florida, Gainesville, FL, 32610, USA
- Department of Molecular Genetics and Microbiology, University of Florida, Gainesville, FL, 32610, USA
| | - Laura P W Ranum
- Center for NeuroGenetics, University of Florida, Gainesville, FL, 32610, USA.
- Department of Molecular Genetics and Microbiology, University of Florida, Gainesville, FL, 32610, USA.
- Department of Neurology, College of Medicine, University of Florida, Gainesville, FL, 32610, USA.
- McKnight Brain Institute, University of Florida, Gainesville, FL, 32610, USA.
- Genetics Institute, University of Florida, Gainesville, FL, 32610, USA.
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12
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Abstract
Microsatellite mutations involving the expansion of tri-, tetra-, penta-, or hexanucleotide repeats cause more than 40 different neurological disorders. Although, traditionally, the position of the repeat within or outside of an open reading frame has been used to focus research on disease mechanisms involving protein loss of function, protein gain of function, or RNA gain of function, the discoveries of bidirectional transcription and repeat-associated non-ATG (RAN) have blurred these distinctions. Here we review what is known about RAN proteins in disease, the mechanisms by which they are produced, and the novel therapeutic opportunities they provide.
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Affiliation(s)
- Lien Nguyen
- Center for NeuroGenetics, Department of Molecular Genetics and Microbiology, Genetics Institute, and McKnight Brain Institute, College of Medicine, University of Florida, Gainesville, Florida 32610, USA;
| | - John Douglas Cleary
- Center for NeuroGenetics, Department of Molecular Genetics and Microbiology, Genetics Institute, and McKnight Brain Institute, College of Medicine, University of Florida, Gainesville, Florida 32610, USA;
| | - Laura P W Ranum
- Center for NeuroGenetics, Department of Molecular Genetics and Microbiology, Genetics Institute, and McKnight Brain Institute, College of Medicine, University of Florida, Gainesville, Florida 32610, USA;
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13
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Abstract
In 2011, an intronic (G4C2)•(G2C4) expansion was shown to cause the most common forms of amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD). This discovery linked ALS with a clinically distinct form of dementia and a larger group of microsatellite repeat diseases, and catalyzed basic and translational research.
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Affiliation(s)
- Amrutha Pattamatta
- Center for Neurogenetics, College of Medicine, University of Florida, Gainesville, FL, USA; Departments of Molecular Genetics and Neurology, College of Medicine, University of Florida, Gainesville, FA, USA
| | - John D Cleary
- Center for Neurogenetics, College of Medicine, University of Florida, Gainesville, FL, USA; Departments of Molecular Genetics and Neurology, College of Medicine, University of Florida, Gainesville, FA, USA
| | - Laura P W Ranum
- Center for Neurogenetics, College of Medicine, University of Florida, Gainesville, FL, USA; Departments of Molecular Genetics and Neurology, College of Medicine, University of Florida, Gainesville, FA, USA; McKnight Brain Institute, University of Florida, Gainesville, FL, USA; Genetics Institute, University of Florida, Gainesville, FL, USA.
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14
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Abstract
Microsatellite expansions cause more than 40 neurological disorders, including Huntington's disease, myotonic dystrophy, and C9ORF72 amyotrophic lateral sclerosis/frontotemporal dementia (ALS/FTD). These repeat expansion mutations can produce repeat-associated non-ATG (RAN) proteins in all three reading frames, which accumulate in disease-relevant tissues. There has been considerable interest in RAN protein products and their downstream consequences, particularly for the dipeptide proteins found in C9ORF72 ALS/FTD. Understanding how RAN translation occurs, what cellular factors contribute to RAN protein accumulation, and how these proteins contribute to disease should lead to a better understanding of the basic mechanisms of gene expression and human disease.
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Affiliation(s)
- John Douglas Cleary
- From the Center for NeuroGenetics
- Departments of Molecular Genetics and Microbiology and
- Genetics Institute, and
| | - Amrutha Pattamatta
- From the Center for NeuroGenetics
- Departments of Molecular Genetics and Microbiology and
- Genetics Institute, and
| | - Laura P W Ranum
- From the Center for NeuroGenetics,
- Departments of Molecular Genetics and Microbiology and
- Genetics Institute, and
- Neurology, College of Medicine
- McKnight Brain Institute, University of Florida, Gainesville, Florida 32610
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15
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Zu T, Cleary JD, Liu Y, Bañez-Coronel M, Bubenik JL, Ayhan F, Ashizawa T, Xia G, Clark HB, Yachnis AT, Swanson MS, Ranum LPW. RAN Translation Regulated by Muscleblind Proteins in Myotonic Dystrophy Type 2. Neuron 2017; 95:1292-1305.e5. [PMID: 28910618 DOI: 10.1016/j.neuron.2017.08.039] [Citation(s) in RCA: 91] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2016] [Revised: 05/31/2017] [Accepted: 08/25/2017] [Indexed: 10/18/2022]
Abstract
Several microsatellite-expansion diseases are characterized by the accumulation of RNA foci and RAN proteins, raising the possibility of a mechanistic connection. We explored this question using myotonic dystrophy type 2, a multisystemic disease thought to be primarily caused by RNA gain-of-function effects. We demonstrate that the DM2 CCTG⋅CAGG expansion expresses sense and antisense tetrapeptide poly-(LPAC) and poly-(QAGR) RAN proteins, respectively. In DM2 autopsy brains, LPAC is found in neurons, astrocytes, and glia in gray matter, and antisense QAGR proteins accumulate within white matter. LPAC and QAGR proteins are toxic to cells independent of RNA gain of function. RNA foci and nuclear sequestration of CCUG transcripts by MBNL1 is inversely correlated with LPAC expression. These data suggest a model that involves nuclear retention of expansion RNAs by RNA-binding proteins (RBPs) and an acute phase in which expansion RNAs exceed RBP sequestration capacity, are exported to the cytoplasm, and undergo RAN translation. VIDEO ABSTRACT.
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Affiliation(s)
- Tao Zu
- Center for NeuroGenetics, University of Florida, Gainesville, FL 32610, USA; Department of Molecular Genetics and Microbiology, University of Florida, Gainesville, FL 32610, USA
| | - John D Cleary
- Center for NeuroGenetics, University of Florida, Gainesville, FL 32610, USA; Department of Molecular Genetics and Microbiology, University of Florida, Gainesville, FL 32610, USA
| | - Yuanjing Liu
- Center for NeuroGenetics, University of Florida, Gainesville, FL 32610, USA; Department of Molecular Genetics and Microbiology, University of Florida, Gainesville, FL 32610, USA
| | - Monica Bañez-Coronel
- Center for NeuroGenetics, University of Florida, Gainesville, FL 32610, USA; Department of Molecular Genetics and Microbiology, University of Florida, Gainesville, FL 32610, USA
| | - Jodi L Bubenik
- Center for NeuroGenetics, University of Florida, Gainesville, FL 32610, USA; Department of Molecular Genetics and Microbiology, University of Florida, Gainesville, FL 32610, USA
| | - Fatma Ayhan
- Center for NeuroGenetics, University of Florida, Gainesville, FL 32610, USA; Department of Molecular Genetics and Microbiology, University of Florida, Gainesville, FL 32610, USA
| | - Tetsuo Ashizawa
- Center for NeuroGenetics, University of Florida, Gainesville, FL 32610, USA; Department of Neurology, University of Florida, Gainesville, FL 32610, USA; McKnight Brain Institute, University of Florida, Gainesville, FL 32610, USA; Neurological Institute, Houston Methodist Hospital, Houston, TX 77030, USA
| | - Guangbin Xia
- Center for NeuroGenetics, University of Florida, Gainesville, FL 32610, USA; Department of Neurology, University of Florida, Gainesville, FL 32610, USA; McKnight Brain Institute, University of Florida, Gainesville, FL 32610, USA
| | - H Brent Clark
- Department of Laboratory Medicine and Pathology, University of Minnesota Medical School, Minneapolis, MN 55455, USA
| | - Anthony T Yachnis
- Department of Pathology, Immunology and Laboratory Medicine, College of Medicine, University of Florida, Gainesville, FL 32610, USA
| | - Maurice S Swanson
- Center for NeuroGenetics, University of Florida, Gainesville, FL 32610, USA; Department of Molecular Genetics and Microbiology, University of Florida, Gainesville, FL 32610, USA; Genetics Institute, University of Florida, Gainesville, FL 32610, USA
| | - Laura P W Ranum
- Center for NeuroGenetics, University of Florida, Gainesville, FL 32610, USA; Department of Molecular Genetics and Microbiology, University of Florida, Gainesville, FL 32610, USA; Department of Neurology, University of Florida, Gainesville, FL 32610, USA; Genetics Institute, University of Florida, Gainesville, FL 32610, USA.
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16
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Khare S, Nick JA, Zhang Y, Galeano K, Butler B, Khoshbouei H, Rayaprolu S, Hathorn T, Ranum LPW, Smithson L, Golde TE, Paucar M, Morse R, Raff M, Simon J, Nordenskjöld M, Wirdefeldt K, Rincon-Limas DE, Lewis J, Kaczmarek LK, Fernandez-Funez P, Nick HS, Waters MF. A KCNC3 mutation causes a neurodevelopmental, non-progressive SCA13 subtype associated with dominant negative effects and aberrant EGFR trafficking. PLoS One 2017; 12:e0173565. [PMID: 28467418 PMCID: PMC5414954 DOI: 10.1371/journal.pone.0173565] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [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: 11/16/2016] [Accepted: 02/23/2017] [Indexed: 11/19/2022] Open
Abstract
The autosomal dominant spinocerebellar ataxias (SCAs) are a diverse group of neurological disorders anchored by the phenotypes of motor incoordination and cerebellar atrophy. Disease heterogeneity is appreciated through varying comorbidities: dysarthria, dysphagia, oculomotor and/or retinal abnormalities, motor neuron pathology, epilepsy, cognitive impairment, autonomic dysfunction, and psychiatric manifestations. Our study focuses on SCA13, which is caused by several allelic variants in the voltage-gated potassium channel KCNC3 (Kv3.3). We detail the clinical phenotype of four SCA13 kindreds that confirm causation of the KCNC3R423H allele. The heralding features demonstrate congenital onset with non-progressive, neurodevelopmental cerebellar hypoplasia and lifetime improvement in motor and cognitive function that implicate compensatory neural mechanisms. Targeted expression of human KCNC3R423H in Drosophila triggers aberrant wing veins, maldeveloped eyes, and fused ommatidia consistent with the neurodevelopmental presentation of patients. Furthermore, human KCNC3R423H expression in mammalian cells results in altered glycosylation and aberrant retention of the channel in anterograde and/or endosomal vesicles. Confirmation of the absence of plasma membrane targeting was based on the loss of current conductance in cells expressing the mutant channel. Mechanistically, genetic studies in Drosophila, along with cellular and biophysical studies in mammalian systems, demonstrate the dominant negative effect exerted by the mutant on the wild-type (WT) protein, which explains dominant inheritance. We demonstrate that ocular co-expression of KCNC3R423H with Drosophila epidermal growth factor receptor (dEgfr) results in striking rescue of the eye phenotype, whereas KCNC3R423H expression in mammalian cells results in aberrant intracellular retention of human epidermal growth factor receptor (EGFR). Together, these results indicate that the neurodevelopmental consequences of KCNC3R423H may be mediated through indirect effects on EGFR signaling in the developing cerebellum. Our results therefore confirm the KCNC3R423H allele as causative for SCA13, through a dominant negative effect on KCNC3WT and links with EGFR that account for dominant inheritance, congenital onset, and disease pathology.
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Affiliation(s)
- Swati Khare
- Department of Neurology, University of Florida, Gainesville, FL, United States of America
- McKnight Brain Institute, University of Florida, Gainesville, FL, United States of America
- Department of Biomedical Engineering, University of Florida, Gainesville, FL, United States of America
| | - Jerelyn A. Nick
- Department of Neurology, University of Florida, Gainesville, FL, United States of America
- McKnight Brain Institute, University of Florida, Gainesville, FL, United States of America
| | - Yalan Zhang
- Department of Pharmacology, Yale University, New Haven, CT, United States of America
| | - Kira Galeano
- Department of Neurology, University of Florida, Gainesville, FL, United States of America
- McKnight Brain Institute, University of Florida, Gainesville, FL, United States of America
| | - Brittany Butler
- McKnight Brain Institute, University of Florida, Gainesville, FL, United States of America
- Department of Neuroscience, University of Florida, Gainesville, FL, United States of America
| | - Habibeh Khoshbouei
- McKnight Brain Institute, University of Florida, Gainesville, FL, United States of America
- Department of Neuroscience, University of Florida, Gainesville, FL, United States of America
| | - Sruti Rayaprolu
- Department of Neuroscience, University of Florida, Gainesville, FL, United States of America
| | - Tyisha Hathorn
- Department of Molecular Genetics and Microbiology, University of Florida, Gainesville, FL, United States of America
| | - Laura P. W. Ranum
- Department of Molecular Genetics and Microbiology, University of Florida, Gainesville, FL, United States of America
| | - Lisa Smithson
- McKnight Brain Institute, University of Florida, Gainesville, FL, United States of America
- Department of Neuroscience, University of Florida, Gainesville, FL, United States of America
| | - Todd E. Golde
- McKnight Brain Institute, University of Florida, Gainesville, FL, United States of America
- Department of Neuroscience, University of Florida, Gainesville, FL, United States of America
| | - Martin Paucar
- Department of Neurology, Karolinska University Hospital, Stockholm, Sweden
- Department of Clinical Neuroscience, Karolinska Institute, Stockholm, Sweden
| | - Richard Morse
- Department of Neurology, Dartmouth-Hitchcock Medical Center, Lebanon, NH, United States of America
| | - Michael Raff
- Genomics Institute, Multicare Health System, Tacoma, WA, United States of America
| | - Julie Simon
- Genomics Institute, Multicare Health System, Tacoma, WA, United States of America
| | - Magnus Nordenskjöld
- Department of Genetics, Karolinska University Hospital, Stockholm, Sweden
- Department of Molecular Medicine and Surgery, Karolinska Institute, Center for Molecular Medicine, Stockholm, Sweden
| | - Karin Wirdefeldt
- Department of Clinical Neuroscience, Karolinska Institute, Stockholm, Sweden
- Department of Medical Epidemiology and Biostatistics, Karolinska Institute, Stockholm, Sweden
| | - Diego E. Rincon-Limas
- Department of Neurology, University of Florida, Gainesville, FL, United States of America
- McKnight Brain Institute, University of Florida, Gainesville, FL, United States of America
| | - Jada Lewis
- McKnight Brain Institute, University of Florida, Gainesville, FL, United States of America
- Department of Neuroscience, University of Florida, Gainesville, FL, United States of America
| | - Leonard K. Kaczmarek
- Department of Pharmacology, Yale University, New Haven, CT, United States of America
| | - Pedro Fernandez-Funez
- Department of Neurology, University of Florida, Gainesville, FL, United States of America
- McKnight Brain Institute, University of Florida, Gainesville, FL, United States of America
| | - Harry S. Nick
- McKnight Brain Institute, University of Florida, Gainesville, FL, United States of America
- Department of Neuroscience, University of Florida, Gainesville, FL, United States of America
| | - Michael F. Waters
- Department of Neurology, University of Florida, Gainesville, FL, United States of America
- McKnight Brain Institute, University of Florida, Gainesville, FL, United States of America
- Department of Biomedical Engineering, University of Florida, Gainesville, FL, United States of America
- Department of Neuroscience, University of Florida, Gainesville, FL, United States of America
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17
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Grima JC, Daigle JG, Arbez N, Cunningham KC, Zhang K, Ochaba J, Geater C, Morozko E, Stocksdale J, Glatzer JC, Pham JT, Ahmed I, Peng Q, Wadhwa H, Pletnikova O, Troncoso JC, Duan W, Snyder SH, Ranum LPW, Thompson LM, Lloyd TE, Ross CA, Rothstein JD. Mutant Huntingtin Disrupts the Nuclear Pore Complex. Neuron 2017; 94:93-107.e6. [PMID: 28384479 PMCID: PMC5595097 DOI: 10.1016/j.neuron.2017.03.023] [Citation(s) in RCA: 229] [Impact Index Per Article: 32.7] [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: 09/28/2016] [Revised: 01/30/2017] [Accepted: 03/13/2017] [Indexed: 01/01/2023]
Abstract
Huntington's disease (HD) is caused by an expanded CAG repeat in the Huntingtin (HTT) gene. The mechanism(s) by which mutant HTT (mHTT) causes disease is unclear. Nucleocytoplasmic transport, the trafficking of macromolecules between the nucleus and cytoplasm, is tightly regulated by nuclear pore complexes (NPCs) made up of nucleoporins (NUPs). Previous studies offered clues that mHTT may disrupt nucleocytoplasmic transport and a mutation of an NUP can cause HD-like pathology. Therefore, we evaluated the NPC and nucleocytoplasmic transport in multiple models of HD, including mouse and fly models, neurons transfected with mHTT, HD iPSC-derived neurons, and human HD brain regions. These studies revealed severe mislocalization and aggregation of NUPs and defective nucleocytoplasmic transport. HD repeat-associated non-ATG (RAN) translation proteins also disrupted nucleocytoplasmic transport. Additionally, overexpression of NUPs and treatment with drugs that prevent aberrant NUP biology also mitigated this transport defect and neurotoxicity, providing future novel therapy targets.
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Affiliation(s)
- Jonathan C Grima
- Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA; Brain Science Institute, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA; Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - J Gavin Daigle
- Brain Science Institute, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA; Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Nicolas Arbez
- Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA; Department of Psychiatry, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Kathleen C Cunningham
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA; Program in Cellular and Molecular Medicine, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Ke Zhang
- Brain Science Institute, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA; Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Joseph Ochaba
- Department of Neurobiology and Behavior, University of California, Irvine, Irvine, CA 92697, USA
| | - Charlene Geater
- Department of Neurobiology and Behavior, University of California, Irvine, Irvine, CA 92697, USA
| | - Eva Morozko
- Department of Neurobiology and Behavior, University of California, Irvine, Irvine, CA 92697, USA
| | - Jennifer Stocksdale
- Department of Neurobiology and Behavior, University of California, Irvine, Irvine, CA 92697, USA
| | - Jenna C Glatzer
- Brain Science Institute, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA; Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Jacqueline T Pham
- Brain Science Institute, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA; Program in Cellular and Molecular Medicine, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Ishrat Ahmed
- Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Qi Peng
- Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Harsh Wadhwa
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Olga Pletnikova
- Department of Pathology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Juan C Troncoso
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA; Department of Pathology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Wenzhen Duan
- Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA; Program in Cellular and Molecular Medicine, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA; Department of Psychiatry, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Solomon H Snyder
- Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA; Department of Psychiatry, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Laura P W Ranum
- Center for NeuroGenetics, Departments of Molecular Genetics and Microbiology and Neurology, College of Medicine, Genetics Institute, McKnight Brain Institute, University of Florida, Gainesville, FL 32611, USA
| | - Leslie M Thompson
- Department of Neurobiology and Behavior, University of California, Irvine, Irvine, CA 92697, USA
| | - Thomas E Lloyd
- Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA; Brain Science Institute, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA; Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA; Program in Cellular and Molecular Medicine, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Christopher A Ross
- Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA; Department of Psychiatry, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Jeffrey D Rothstein
- Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA; Brain Science Institute, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA; Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA; Program in Cellular and Molecular Medicine, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA.
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18
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Xia G, Gao Y, Jin S, Subramony SH, Terada N, Ranum LPW, Swanson MS, Ashizawa T. Genome modification leads to phenotype reversal in human myotonic dystrophy type 1 induced pluripotent stem cell-derived neural stem cells. Stem Cells 2016; 33:1829-38. [PMID: 25702800 DOI: 10.1002/stem.1970] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2014] [Accepted: 01/17/2015] [Indexed: 12/15/2022]
Abstract
Myotonic dystrophy type 1 (DM1) is caused by expanded CTG repeats in the 3'-untranslated region (3' UTR) of the DMPK gene. Correcting the mutation in DM1 stem cells would be an important step toward autologous stem cell therapy. The objective of this study is to demonstrate in vitro genome editing to prevent production of toxic mutant transcripts and reverse phenotypes in DM1 stem cells. Genome editing was performed in DM1 neural stem cells (NSCs) derived from human DM1 induced pluripotent stem (iPS) cells. An editing cassette containing SV40/bGH polyA signals was integrated upstream of the CTG repeats by TALEN-mediated homologous recombination (HR). The expression of mutant CUG repeats transcript was monitored by nuclear RNA foci, the molecular hallmarks of DM1, using RNA fluorescence in situ hybridization. Alternative splicing of microtubule-associated protein tau (MAPT) and muscleblind-like (MBNL) proteins were analyzed to further monitor the phenotype reversal after genome modification. The cassette was successfully inserted into DMPK intron 9 and this genomic modification led to complete disappearance of nuclear RNA foci. MAPT and MBNL 1, 2 aberrant splicing in DM1 NSCs were reversed to normal pattern in genome-modified NSCs. Genome modification by integration of exogenous polyA signals upstream of the DMPK CTG repeat expansion prevents the production of toxic RNA and leads to phenotype reversal in human DM1 iPS-cells derived stem cells. Our data provide proof-of-principle evidence that genome modification may be used to generate genetically modified progenitor cells as a first step toward autologous cell transfer therapy for DM1.
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Affiliation(s)
- Guangbin Xia
- Department of Neurology, University of Florida, College of Medicine, Gainesville, Florida, USA.,Center for Cellular Reprogramming, University of Florida, College of Medicine, Gainesville, Florida, USA.,Center for NeuroGenetics, University of Florida, College of Medicine, Gainesville, Florida, USA.,The Evelyn L & William F. McKnight Brain Institute, University of Florida, Gainesville, Florida, USA.,Department of Neuroscience, University of Florida, Gainesville, Florida, USA
| | - Yuanzheng Gao
- Department of Neurology, University of Florida, College of Medicine, Gainesville, Florida, USA.,The Evelyn L & William F. McKnight Brain Institute, University of Florida, Gainesville, Florida, USA
| | - Shouguang Jin
- Department of Molecular Genetics and Microbiology, College of Medicine, Gainesville, Florida, USA
| | - S H Subramony
- Department of Neurology, University of Florida, College of Medicine, Gainesville, Florida, USA.,Center for NeuroGenetics, University of Florida, College of Medicine, Gainesville, Florida, USA.,The Evelyn L & William F. McKnight Brain Institute, University of Florida, Gainesville, Florida, USA
| | - Naohiro Terada
- Center for Cellular Reprogramming, University of Florida, College of Medicine, Gainesville, Florida, USA.,Department of Pathology, Immunology & Laboratory Medicine, College of Medicine, University of Florida, Gainesville, Florida, USA
| | - Laura P W Ranum
- Department of Neurology, University of Florida, College of Medicine, Gainesville, Florida, USA.,Center for NeuroGenetics, University of Florida, College of Medicine, Gainesville, Florida, USA.,Department of Molecular Genetics and Microbiology, College of Medicine, Gainesville, Florida, USA.,Genetics Institute, University of Florida, Gainesville, Florida, USA
| | - Maurice S Swanson
- Center for NeuroGenetics, University of Florida, College of Medicine, Gainesville, Florida, USA.,Department of Molecular Genetics and Microbiology, College of Medicine, Gainesville, Florida, USA.,Genetics Institute, University of Florida, Gainesville, Florida, USA
| | - Tetsuo Ashizawa
- Department of Neurology, University of Florida, College of Medicine, Gainesville, Florida, USA.,Center for Cellular Reprogramming, University of Florida, College of Medicine, Gainesville, Florida, USA.,Center for NeuroGenetics, University of Florida, College of Medicine, Gainesville, Florida, USA.,The Evelyn L & William F. McKnight Brain Institute, University of Florida, Gainesville, Florida, USA
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19
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Bañez-Coronel M, Ayhan F, Tarabochia AD, Zu T, Perez BA, Tusi SK, Pletnikova O, Borchelt DR, Ross CA, Margolis RL, Yachnis AT, Troncoso JC, Ranum LPW. RAN Translation in Huntington Disease. Neuron 2016; 88:667-77. [PMID: 26590344 DOI: 10.1016/j.neuron.2015.10.038] [Citation(s) in RCA: 244] [Impact Index Per Article: 30.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2015] [Revised: 09/05/2015] [Accepted: 10/15/2015] [Indexed: 11/30/2022]
Abstract
Huntington disease (HD) is caused by a CAG ⋅ CTG expansion in the huntingtin (HTT) gene. While most research has focused on the HTT polyGln-expansion protein, we demonstrate that four additional, novel, homopolymeric expansion proteins (polyAla, polySer, polyLeu, and polyCys) accumulate in HD human brains. These sense and antisense repeat-associated non-ATG (RAN) translation proteins accumulate most abundantly in brain regions with neuronal loss, microglial activation and apoptosis, including caudate/putamen, white matter, and, in juvenile-onset cases, also the cerebellum. RAN protein accumulation and aggregation are length dependent, and individual RAN proteins are toxic to neural cells independent of RNA effects. These data suggest RAN proteins contribute to HD and that therapeutic strategies targeting both sense and antisense genes may be required for efficacy in HD patients. This is the first demonstration that RAN proteins are expressed across an expansion located in an open reading frame and suggests RAN translation may also contribute to other polyglutamine diseases.
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Affiliation(s)
- Monica Bañez-Coronel
- Center for NeuroGenetics, University of Florida, Gainesville, FL 32610, USA; Department of Molecular Genetics and Microbiology, University of Florida, Gainesville, FL 32610, USA
| | - Fatma Ayhan
- Center for NeuroGenetics, University of Florida, Gainesville, FL 32610, USA; Department of Molecular Genetics and Microbiology, University of Florida, Gainesville, FL 32610, USA
| | - Alex D Tarabochia
- Center for NeuroGenetics, University of Florida, Gainesville, FL 32610, USA; Department of Molecular Genetics and Microbiology, University of Florida, Gainesville, FL 32610, USA
| | - Tao Zu
- Center for NeuroGenetics, University of Florida, Gainesville, FL 32610, USA; Department of Molecular Genetics and Microbiology, University of Florida, Gainesville, FL 32610, USA
| | - Barbara A Perez
- Center for NeuroGenetics, University of Florida, Gainesville, FL 32610, USA; Department of Molecular Genetics and Microbiology, University of Florida, Gainesville, FL 32610, USA
| | - Solaleh Khoramian Tusi
- Center for NeuroGenetics, University of Florida, Gainesville, FL 32610, USA; Department of Molecular Genetics and Microbiology, University of Florida, Gainesville, FL 32610, USA; Genetics Institute, University of Florida, Gainesville, FL 32610, USA
| | - Olga Pletnikova
- Department of Pathology, The John Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - David R Borchelt
- Center for NeuroGenetics, University of Florida, Gainesville, FL 32610, USA; Department of Neuroscience, University of Florida, Gainesville, FL 32610, USA
| | - Christopher A Ross
- Division of Neurobiology, The John Hopkins University School of Medicine, Baltimore, MD 21205, USA; Department of Psychiatry, The John Hopkins University School of Medicine, Baltimore, MD 21205, USA; Department of Neurology, The John Hopkins University School of Medicine, Baltimore, MD 21205, USA; Department of Pharmacology, The John Hopkins University School of Medicine, Baltimore, MD 21205, USA; Department of Neuroscience, The John Hopkins University School of Medicine, Baltimore, MD 21205, USA; Program in Cellular and Molecular Medicine, The John Hopkins University School of Medicine, Baltimore, MD 21205, USA; Baltimore Huntington's Disease Center, The John Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Russell L Margolis
- Division of Neurobiology, The John Hopkins University School of Medicine, Baltimore, MD 21205, USA; Department of Psychiatry, The John Hopkins University School of Medicine, Baltimore, MD 21205, USA; Department of Neurology, The John Hopkins University School of Medicine, Baltimore, MD 21205, USA; Department of Neuroscience, The John Hopkins University School of Medicine, Baltimore, MD 21205, USA; Baltimore Huntington's Disease Center, The John Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Anthony T Yachnis
- Department of Pathology, Immunology and Laboratory Medicine, College of Medicine, University of Florida, Gainesville, FL 32610, USA
| | - Juan C Troncoso
- Department of Pathology, The John Hopkins University School of Medicine, Baltimore, MD 21205, USA; Department of Neurology, The John Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Laura P W Ranum
- Center for NeuroGenetics, University of Florida, Gainesville, FL 32610, USA; Department of Molecular Genetics and Microbiology, University of Florida, Gainesville, FL 32610, USA; Department of Neurology, University of Florida, Gainesville, FL 32610, USA; Genetics Institute, University of Florida, Gainesville, FL 32610, USA.
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20
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Goodwin M, Mohan A, Batra R, Lee KY, Charizanis K, Fernández Gómez FJ, Eddarkaoui S, Sergeant N, Buée L, Kimura T, Clark HB, Dalton J, Takamura K, Weyn-Vanhentenryck SM, Zhang C, Reid T, Ranum LPW, Day JW, Swanson MS. MBNL Sequestration by Toxic RNAs and RNA Misprocessing in the Myotonic Dystrophy Brain. Cell Rep 2015; 12:1159-68. [PMID: 26257173 DOI: 10.1016/j.celrep.2015.07.029] [Citation(s) in RCA: 100] [Impact Index Per Article: 11.1] [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: 03/24/2015] [Revised: 06/24/2015] [Accepted: 07/14/2015] [Indexed: 11/19/2022] Open
Abstract
For some neurological disorders, disease is primarily RNA mediated due to expression of non-coding microsatellite expansion RNAs (RNA(exp)). Toxicity is thought to result from enhanced binding of proteins to these expansions and depletion from their normal cellular targets. However, experimental evidence for this sequestration model is lacking. Here, we use HITS-CLIP and pre-mRNA processing analysis of human control versus myotonic dystrophy (DM) brains to provide compelling evidence for this RNA toxicity model. MBNL2 binds directly to DM repeat expansions in the brain, resulting in depletion from its normal RNA targets with downstream effects on alternative splicing and polyadenylation. Similar RNA processing defects were detected in Mbnl compound-knockout mice, highlighted by dysregulation of Mapt splicing and fetal tau isoform expression in adults. These results demonstrate that MBNL proteins are directly sequestered by RNA(exp) in the DM brain and introduce a powerful experimental tool to evaluate RNA-mediated toxicity in other expansion diseases.
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Affiliation(s)
- Marianne Goodwin
- Department of Molecular Genetics and Microbiology, Center for NeuroGenetics and the Genetics Institute, University of Florida, College of Medicine, Gainesville, FL 32610, USA
| | - Apoorva Mohan
- Department of Molecular Genetics and Microbiology, Center for NeuroGenetics and the Genetics Institute, University of Florida, College of Medicine, Gainesville, FL 32610, USA
| | - Ranjan Batra
- Department of Molecular Genetics and Microbiology, Center for NeuroGenetics and the Genetics Institute, University of Florida, College of Medicine, Gainesville, FL 32610, USA
| | - Kuang-Yung Lee
- Department of Molecular Genetics and Microbiology, Center for NeuroGenetics and the Genetics Institute, University of Florida, College of Medicine, Gainesville, FL 32610, USA; Department of Neurology, Chang Gung Memorial Hospital, Keelung 20401, Taiwan
| | - Konstantinos Charizanis
- Department of Molecular Genetics and Microbiology, Center for NeuroGenetics and the Genetics Institute, University of Florida, College of Medicine, Gainesville, FL 32610, USA; InSiliGen LLC, Gainesville, FL 32606, USA
| | - Francisco José Fernández Gómez
- Inserm UMR S1172, Alzheimer and Tauopathies, Université Lille Nord de France, Centre Jean-Pierre Aubert, 1 Place Verdun, 59045 Lille, France
| | - Sabiha Eddarkaoui
- Inserm UMR S1172, Alzheimer and Tauopathies, Université Lille Nord de France, Centre Jean-Pierre Aubert, 1 Place Verdun, 59045 Lille, France
| | - Nicolas Sergeant
- Inserm UMR S1172, Alzheimer and Tauopathies, Université Lille Nord de France, Centre Jean-Pierre Aubert, 1 Place Verdun, 59045 Lille, France
| | - Luc Buée
- Inserm UMR S1172, Alzheimer and Tauopathies, Université Lille Nord de France, Centre Jean-Pierre Aubert, 1 Place Verdun, 59045 Lille, France
| | - Takashi Kimura
- Division of Neurology, Department of Internal Medicine, Hyogo College of Medicine, Hyogo 663-8501, Japan
| | - H Brent Clark
- Departments of Laboratory Medicine and Pathology, Neurology, Neurosurgery, and Genetics, Cell Biology, and Development, University of Minnesota Medical School, Minneapolis, MN 55455, USA
| | - Joline Dalton
- Departments of Laboratory Medicine and Pathology, Neurology, Neurosurgery, and Genetics, Cell Biology, and Development, University of Minnesota Medical School, Minneapolis, MN 55455, USA
| | - Kenji Takamura
- Departments of Laboratory Medicine and Pathology, Neurology, Neurosurgery, and Genetics, Cell Biology, and Development, University of Minnesota Medical School, Minneapolis, MN 55455, USA
| | - Sebastien M Weyn-Vanhentenryck
- Department of Systems Biology, Department of Biochemistry and Molecular Biophysics, Center for Motor Neuron Biology and Disease, Columbia University, New York, NY 10032, USA
| | - Chaolin Zhang
- Department of Systems Biology, Department of Biochemistry and Molecular Biophysics, Center for Motor Neuron Biology and Disease, Columbia University, New York, NY 10032, USA
| | - Tammy Reid
- Department of Molecular Genetics and Microbiology, Center for NeuroGenetics and the Genetics Institute, University of Florida, College of Medicine, Gainesville, FL 32610, USA
| | - Laura P W Ranum
- Department of Molecular Genetics and Microbiology, Center for NeuroGenetics and the Genetics Institute, University of Florida, College of Medicine, Gainesville, FL 32610, USA
| | - John W Day
- Department of Neurology and Neurological Sciences, School of Medicine, Stanford University, Palo Alto, CA 94305, USA
| | - Maurice S Swanson
- Department of Molecular Genetics and Microbiology, Center for NeuroGenetics and the Genetics Institute, University of Florida, College of Medicine, Gainesville, FL 32610, USA.
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21
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Cleary JD, Ranum LPW. Repeat associated non-ATG (RAN) translation: new starts in microsatellite expansion disorders. Curr Opin Genet Dev 2014; 26:6-15. [PMID: 24852074 DOI: 10.1016/j.gde.2014.03.002] [Citation(s) in RCA: 93] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2013] [Revised: 01/31/2014] [Accepted: 03/11/2014] [Indexed: 12/14/2022]
Abstract
Microsatellite-expansion diseases are a class of neurological and neuromuscular disorders caused by the expansion of short stretches of repetitive DNA (e.g. GGGGCC, CAG, CTG …) within the human genome. Since their discovery 20 years ago, research into how microsatellites expansions cause disease has been examined using the model that these genes are expressed in one direction and that expansion mutations only encode proteins when located in an ATG-initiated open reading frame. The fact that these mutations are often bidirectionally transcribed combined with the recent discovery of repeat associated non-ATG (RAN) translation provides new perspectives on how these expansion mutations are expressed and impact disease. Two expansion transcripts and a set of unexpected RAN proteins must now be considered for both coding and 'non-coding' expansion disorders. RAN proteins have been reported in a growing number of diseases, including spinocerebellar ataxia type 8 (SCA8), myotonic dystrophy type 1 (DM1), Fragile-X tremor ataxia syndrome (FXTAS), and C9ORF72 amyotrophic lateral sclerosis (ALS)/frontotemporal dementia (FTD).
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Affiliation(s)
- John Douglas Cleary
- Center for NeuroGenetics, College of Medicine, University of Florida, Gainesville, FL, USA; Department of Molecular Genetics & Microbiology, College of Medicine, University of Florida, Gainesville, FL, USA; Genetics Institute, College of Medicine, University of Florida, Gainesville, FL, USA
| | - Laura P W Ranum
- Center for NeuroGenetics, College of Medicine, University of Florida, Gainesville, FL, USA; Department of Molecular Genetics & Microbiology, College of Medicine, University of Florida, Gainesville, FL, USA; Department of Neurology, College of Medicine, University of Florida, Gainesville, FL, USA; Genetics Institute, College of Medicine, University of Florida, Gainesville, FL, USA.
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Lee KY, Li M, Manchanda M, Batra R, Charizanis K, Mohan A, Warren SA, Chamberlain CM, Finn D, Hong H, Ashraf H, Kasahara H, Ranum LPW, Swanson MS. Compound loss of muscleblind-like function in myotonic dystrophy. EMBO Mol Med 2013; 5:1887-900. [PMID: 24293317 PMCID: PMC3914532 DOI: 10.1002/emmm.201303275] [Citation(s) in RCA: 129] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2013] [Revised: 08/30/2013] [Accepted: 09/06/2013] [Indexed: 02/04/2023] Open
Abstract
Myotonic dystrophy (DM) is a multi-systemic disease that impacts cardiac and skeletal muscle as well as the central nervous system (CNS). DM is unusual because it is an RNA-mediated disorder due to the expression of toxic microsatellite expansion RNAs that alter the activities of RNA processing factors, including the muscleblind-like (MBNL) proteins. While these mutant RNAs inhibit MBNL1 splicing activity in heart and skeletal muscles, Mbnl1 knockout mice fail to recapitulate the full-range of DM symptoms in these tissues. Here, we generate mouse Mbnl compound knockouts to test the hypothesis that Mbnl2 functionally compensates for Mbnl1 loss. Although Mbnl1−/−; Mbnl2−/− double knockouts (DKOs) are embryonic lethal, Mbnl1−/−; Mbnl2+/− mice are viable but develop cardinal features of DM muscle disease including reduced lifespan, heart conduction block, severe myotonia and progressive skeletal muscle weakness. Mbnl2 protein levels are elevated in Mbnl1−/− knockouts where Mbnl2 targets Mbnl1-regulated exons. These findings support the hypothesis that compound loss of MBNL function is a critical event in DM pathogenesis and provide novel mouse models to investigate additional pathways disrupted in this RNA-mediated disease.
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Affiliation(s)
- Kuang-Yung Lee
- Department of Molecular Genetics and Microbiology, Center for NeuroGenetics and the Genetics Institute, University of Florida, College of Medicine, Gainesville, FL, USA; Department of Neurology, Chang Gung Memorial Hospital, Keelung, Taiwan
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Ishiura H, Takahashi Y, Mitsui J, Yoshida S, Kihira T, Kokubo Y, Kuzuhara S, Ranum LPW, Tamaoki T, Ichikawa Y, Date H, Goto J, Tsuji S. C9ORF72 repeat expansion in amyotrophic lateral sclerosis in the Kii peninsula of Japan. ACTA ACUST UNITED AC 2012; 69:1154-8. [PMID: 22637429 DOI: 10.1001/archneurol.2012.1219] [Citation(s) in RCA: 81] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
BACKGROUND In the Kii peninsula of Japan, high prevalences of amyotrophic lateral sclerosis (ALS) and parkinsonism-dementia complex have been reported. There are 2 major foci with a high prevalence, which include the southernmost region neighboring the Koza River (Kozagawa and Kushimoto towns in Wakayama prefecture) and the Hohara district (Mie prefecture). OBJECTIVE To delineate the molecular basis of ALS in the Kii peninsula of Japan, we analyzed hexanucleotide repeat expansion in the chromosome 9 open reading frame 72 (C9ORF72) gene, which has recently been identified as a frequent cause of ALS and frontotemporal dementia in the white population. DESIGN Case series. SETTING University hospitals. PATIENTS Twenty-one patients (1 familial patient and 20 sporadic patients) with ALS from Wakayama prefecture, and 16 patients with ALS and 16 patients with parkinsonism-dementia complex originating from Mie prefecture surveyed in 1994 through 2011 were enrolled in the study. In addition, 40 probands with familial ALS and 217 sporadic patients with ALS recruited from other areas of Japan were also enrolled in this study. MAIN OUTCOME MEASURES After screening by repeat-primed polymerase chain reaction, Southern blot hybridization analysis was performed to confirm the expanded alleles. RESULTS We identified 3 patients with ALS (20%) with the repeat expansion in 1 of the 2 disease foci. The proportion is significantly higher than those in other regions in Japan. Detailed haplotype analyses revealed an extended shared haplotype in the 3 patients with ALS, suggesting a founder effect. CONCLUSIONS Our findings indicate that the repeat expansion partly accounts for the high prevalence of ALS in the Kii peninsula.
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Affiliation(s)
- Hiroyuki Ishiura
- Department of Neurology, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan
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Ranum LPW, Daughters RS, Tuttle DL, Gao W, Ikeda Y, Moseley ML, Ebner T, Swanson MS. [Double the trouble: bidirectional expression of the SCA8 CAG/CTG expansion mutation - evidence for RNA and protein gain of function effects]. Rinsho Shinkeigaku 2012; 50:982-3. [PMID: 21921535 DOI: 10.5692/clinicalneurol.50.982] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Affiliation(s)
- Laura P W Ranum
- Department of Genetics, Cell Biology, and Development, University of Minnesota, Minneapolis, USA
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Chamberlain CM, Ranum LPW. Mouse model of muscleblind-like 1 overexpression: skeletal muscle effects and therapeutic promise. Hum Mol Genet 2012; 21:4645-54. [PMID: 22846424 DOI: 10.1093/hmg/dds306] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
Myotonic dystrophy (DM) is a multisystemic disease caused by CTG or CCTG expansion mutations. There is strong evidence that DM1 CUG and DM2 CCUG expansion transcripts sequester muscleblind-like (MBNL) proteins and that loss of MBNL function causes alternative splicing abnormalities that contribute to disease. Because MBNL1 loss is thought to play an important role in disease and localized AAV delivery of MBNL1 partially rescues skeletal muscle pathology in DM mice, there is strong interest in MBNL1 overexpression as a therapeutic strategy. We developed the first transgenic MBNL1 overexpression mouse model (MBNL1-OE) to test the safety and efficacy of multisystemic MBNL1 overexpression. First, we demonstrate that MBNL1 overexpression is generally well-tolerated in skeletal muscle. Second, we show the surprising result that premature shifts in alternative splicing of MBNL1-regulated genes in multiple organ systems are compatible with life and do not cause embryonic lethality. Third, we show for the first time that early and long-term MBNL1 overexpression prevents CUG-induced myotonia, myopathy and alternative splicing abnormalities in DM1 mice. In summary, MBNL1 overexpression may be a valuable strategy for treating the skeletal muscle features of DM.
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Martins S, Soong BW, Wong VCN, Giunti P, Stevanin G, Ranum LPW, Sasaki H, Riess O, Tsuji S, Coutinho P, Amorim A, Sequeiros J, Nicholson GA. Mutational Origin of Machado-Joseph Disease in the Australian Aboriginal Communities of Groote Eylandt and Yirrkala. ACTA ACUST UNITED AC 2012; 69:746-51. [DOI: 10.1001/archneurol.2011.2504] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
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Abstract
In 1994, Ranum and colleagues identified a ten-generation American kindred with a relatively mild autosomal dominant form of spinocerebellar ataxia (Ranum et al., 1994). The mutation was mapped to the centromeric region of chromosome 11, and the disorder designated SCA5 (Ranum et al., 1994). Using a multifaceted mapping approach, Ikeda et al. (2006) discovered that β-III spectrin (SPTBN2) mutations cause spinocerebellar ataxia type 5 (SCA5) in the American kindred and two additional independently reported SCA5 families. The American and French families have separate in-frame deletions of 39 and 15 bp, respectively, in the third of 17 spectrin repeat motifs. A third mutation, found in a German family, is located in the second calponin homology domain, a region known to bind actin and Arp1. Consistent with Purkinje cell degeneration in SCA5, β-III spectrin is highly expressed in cerebellar Purkinje cells. TIRF microscopy performed on cell lines transiently transfected with mutant or wild-type spectrin shows that mutant β-III spectrin fails to stabilize the glutamate transporter EAAT4 at the plasma membrane. Additionally, marked differences in EAAT4 and GluRδ2 were found by protein blot and cell fractionation in SCA5 autopsy tissue. This review summarizes data showing that β-III spectrin mutations are a novel cause of neurodegenerative disease, which may affect the stabilization or trafficking of membrane proteins.
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Affiliation(s)
- Katherine A Dick
- Department of Genetics, Cell Biology, and Development, University of Minnesota, Minneapolis, MN, USA
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Affiliation(s)
- Yoshio Ikeda
- Department of Genetics, Cell Biology, and Development, University of Minnesota, Minneapolis, MN 55455, USA
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Figueroa KP, Waters MF, Garibyan V, Bird TD, Gomez CM, Ranum LPW, Minassian NA, Papazian DM, Pulst SM. Frequency of KCNC3 DNA variants as causes of spinocerebellar ataxia 13 (SCA13). PLoS One 2011; 6:e17811. [PMID: 21479265 PMCID: PMC3066194 DOI: 10.1371/journal.pone.0017811] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.4] [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: 11/04/2010] [Accepted: 02/14/2011] [Indexed: 01/16/2023] Open
Abstract
Background Gain-of function or dominant-negative mutations in the voltage-gated potassium channel KCNC3 (Kv3.3) were recently identified as a cause of autosomal dominant spinocerebellar ataxia. Our objective was to describe the frequency of mutations associated with KCNC3 in a large cohort of index patients with sporadic or familial ataxia presenting to three US ataxia clinics at academic medical centers. Methodology DNA sequence analysis of the coding region of the KCNC3 gene was performed in 327 index cases with ataxia. Analysis of channel function was performed by expression of DNA variants in Xenopus oocytes. Principal Findings Sequence analysis revealed two non-synonymous substitutions in exon 2 and five intronic changes, which were not predicted to alter splicing. We identified another pedigree with the p.Arg423His mutation in the highly conserved S4 domain of this channel. This family had an early-onset of disease and associated seizures in one individual. The second coding change, p.Gly263Asp, subtly altered biophysical properties of the channel, but was unlikely to be disease-associated as it occurred in an individual with an expansion of the CAG repeat in the CACNA1A calcium channel. Conclusions Mutations in KCNC3 are a rare cause of spinocerebellar ataxia with a frequency of less than 1%. The p.Arg423His mutation is recurrent in different populations and associated with early onset. In contrast to previous p.Arg423His mutation carriers, we now observed seizures and mild mental retardation in one individual. This study confirms the wide phenotypic spectrum in SCA13.
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Affiliation(s)
- Karla P. Figueroa
- Department of Neurology, University of Utah, Salt Lake City, Utah, United States of America
| | - Michael F. Waters
- Departments of Neurology and Neuroscience, University of Florida, Gainesville, Florida, United States of America
| | - Vartan Garibyan
- Department of Neurology, University of Utah, Salt Lake City, Utah, United States of America
| | - Thomas D. Bird
- Department of Neurology, University of Washington, Seattle, Washington, United States of America
- Veterans Affairs Medical Center, Seattle, Washington, United States of America
| | - Christopher M. Gomez
- Department of Neurology, University of Chicago, Chicago, Illinois, United States of America
| | - Laura P. W. Ranum
- Department of Genetics, Cell Biology and Development and Institute for Translational Neuroscience, University of Minnesota, Minneapolis, Minnesota, United States of America
| | - Natali A. Minassian
- Department of Physiology, University of California Los Angeles, Los Angeles, California, United States of America
| | - Diane M. Papazian
- Department of Physiology, University of California Los Angeles, Los Angeles, California, United States of America
| | - Stefan M. Pulst
- Department of Neurology, University of Utah, Salt Lake City, Utah, United States of America
- Brain Institute, University of Utah, Salt Lake City, Utah, United States of America
- * E-mail:
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Coenen MJH, Tieleman AA, Schijvenaars MMVAP, Leferink M, Ranum LPW, Scheffer H, van Engelen BGM. Dutch myotonic dystrophy type 2 patients and a North-African DM2 family carry the common European founder haplotype. Eur J Hum Genet 2011; 19:567-70. [PMID: 21224892 DOI: 10.1038/ejhg.2010.233] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
Myotonic dystrophy type 2 (DM2) is a progressive multisystem disease with muscle weakness and myotonia as main characteristics. The disease is caused by a repeat expansion in the zinc-finger protein 9 (ZNF9) gene on chromosome 3q21. Several reports show that patients from European ancestry share an identical haplotype surrounding the ZNF9 gene. In this study, we investigated whether the Dutch DM2 population carries the same founder haplotype. In all, 40 Dutch DM2 patients from 16 families were genotyped for eight short tandem repeat markers surrounding the ZNF9 gene. In addition, the single-nucleotide polymorphism (SNP) rs1871922 located in the first intron of DM2 was genotyped. Results were compared with previously published haplotypes from unrelated Caucasian patients. The repeat lengths identified in this study were in agreement with existing literature. In 36 patients of our population, we identified three common haplotypes. One patient showed overlap with the common haplotype for only one marker closest to the ZNF9 gene. The haplotype from a family originating from Morocco showed overlap with that of the patients of European descent for a region of 222 kb. All patients carried at least one C allele of SNP rs1871922 indicating that all patients carry the European founder haplotype. We conclude that DM2 patients from the Netherlands, including a North-African family, harbor a common haplotype surrounding the ZNF9 gene. This data show that the Dutch patients carry the common founder haplotype and strongly suggest that DM2 mutations in Europe and North Africa originate from a single ancestral founder.
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Affiliation(s)
- Marieke J H Coenen
- Department of Human Genetics, Institute for Genetic and Metabolic Diseases, Nijmegen Centre for Evidence Based Practice, Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands.
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Lorenzo DN, Li MG, Mische SE, Armbrust KR, Ranum LPW, Hays TS. Spectrin mutations that cause spinocerebellar ataxia type 5 impair axonal transport and induce neurodegeneration in Drosophila. ACTA ACUST UNITED AC 2010; 189:143-58. [PMID: 20368622 PMCID: PMC2854382 DOI: 10.1083/jcb.200905158] [Citation(s) in RCA: 77] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
How spectrin mutations caused Purkinje cell death becomes clearer following studies that examined the effect of expressing mutant SCA5 in the fly eye. Mutant spectrin causes deficits in synapse formation at the neuromuscular junction and disrupts vesicular trafficking. Spinocerebellar ataxia type 5 (SCA5) is an autosomal dominant neurodegenerative disorder caused by mutations in the SPBTN2 gene encoding β-III–spectrin. To investigate the molecular basis of SCA5, we established a series of transgenic Drosophila models that express human β-III–spectrin or fly β-spectrin proteins containing SCA5 mutations. Expression of the SCA5 mutant spectrin in the eye causes a progressive neurodegenerative phenotype, and expression in larval neurons results in posterior paralysis, reduced synaptic terminal growth, and axonal transport deficits. These phenotypes are genetically enhanced by both dynein and dynactin loss-of-function mutations. In summary, we demonstrate that SCA5 mutant spectrin causes adult-onset neurodegeneration in the fly eye and disrupts fundamental intracellular transport processes that are likely to contribute to this progressive neurodegenerative disease.
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Affiliation(s)
- Damaris N Lorenzo
- Department of Genetics, Cell Biology, and Development, University of Minnesota, Minneapolis, MN 55455, USA
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Daughters RS, Tuttle DL, Gao W, Ikeda Y, Moseley ML, Ebner TJ, Swanson MS, Ranum LPW. RNA gain-of-function in spinocerebellar ataxia type 8. PLoS Genet 2009; 5:e1000600. [PMID: 19680539 PMCID: PMC2719092 DOI: 10.1371/journal.pgen.1000600] [Citation(s) in RCA: 226] [Impact Index Per Article: 15.1] [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: 04/07/2009] [Accepted: 07/14/2009] [Indexed: 01/19/2023] Open
Abstract
Microsatellite expansions cause a number of dominantly-inherited neurological diseases. Expansions in coding-regions cause protein gain-of-function effects, while non-coding expansions produce toxic RNAs that alter RNA splicing activities of MBNL and CELF proteins. Bi-directional expression of the spinocerebellar ataxia type 8 (SCA8) CTG CAG expansion produces CUG expansion RNAs (CUGexp) from the ATXN8OS gene and a nearly pure polyglutamine expansion protein encoded by ATXN8 CAGexp transcripts expressed in the opposite direction. Here, we present three lines of evidence that RNA gain-of-function plays a significant role in SCA8: 1) CUGexp transcripts accumulate as ribonuclear inclusions that co-localize with MBNL1 in selected neurons in the brain; 2) loss of Mbnl1 enhances motor deficits in SCA8 mice; 3) SCA8 CUGexp transcripts trigger splicing changes and increased expression of the CUGBP1-MBNL1 regulated CNS target, GABA-A transporter 4 (GAT4/Gabt4). In vivo optical imaging studies in SCA8 mice confirm that Gabt4 upregulation is associated with the predicted loss of GABAergic inhibition within the granular cell layer. These data demonstrate that CUGexp transcripts dysregulate MBNL/CELF regulated pathways in the brain and provide mechanistic insight into the CNS effects of other CUGexp disorders. Moreover, our demonstration that relatively short CUGexp transcripts cause RNA gain-of-function effects and the growing number of antisense transcripts recently reported in mammalian genomes suggest unrecognized toxic RNAs contribute to the pathophysiology of polyglutamine CAG CTG disorders. We describe several lines of evidence that RNA gain-of-function effects play a significant role in spinocerebellar ataxia type 8 (SCA8) and has broader implications for understanding the CNS effects of other trinucleotide expansion disorders including myotonic dystrophy type 1, Huntington disease like-2, and spinocerebellar ataxia type 7. The SCA8 mutation is bidirectionally transcribed resulting in the expression of CUGexp transcripts from ATXN8OS and CAGexp transcripts and polyglutamine protein from the overlapping ATXN8 gene. These data suggest that SCA8 pathogenesis involves toxic gain-of-function effects at the RNA (CUGexp) and/or protein (PolyQ) levels. We present three lines of evidence that CUGexp transcripts play a significant role in SCA8: 1) CUGexp transcripts accumulate as ribonuclear inclusions that co-localize with MBNL1 in selected neurons; 2) loss of Mbnl1 enhances motor deficits in SCA8 mice; 3) SCA8 CUGexp transcripts trigger alternative splicing changes and increased expression of the CUGBP1-MBNL1 regulated CNS target, GABA-A transporter 4 (GAT4/Gabt4) which is associated with the predicted loss of GABAergic inhibition within the granular cell layer in SCA8 mice. Additionally, alternative splicing changes and GAT4 upregulation are induced by CUGexp but not CAGexp transcripts. From a therapeutic viewpoint, it is promising that this change is reversed in cells overexpressing MBNL1.
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Affiliation(s)
- Randy S. Daughters
- Department of Genetics, Cell Biology, and Development, University of Minnesota, Minneapolis, Minnesota, United States of America
- Institute of Human Genetics, University of Minnesota, Minneapolis, Minnesota, United States of America
| | - Daniel L. Tuttle
- Department of Molecular Genetics and Microbiology, University of Florida, Gainesville, Florida, United States of America
- Genetics Institute, University of Florida, Gainesville, Florida, United States of America
| | - Wangcai Gao
- Department of Neuroscience, University of Minnesota, Minneapolis, Minnesota, United States of America
| | - Yoshio Ikeda
- Department of Genetics, Cell Biology, and Development, University of Minnesota, Minneapolis, Minnesota, United States of America
- Institute of Human Genetics, University of Minnesota, Minneapolis, Minnesota, United States of America
| | - Melinda L. Moseley
- Department of Genetics, Cell Biology, and Development, University of Minnesota, Minneapolis, Minnesota, United States of America
- Institute of Human Genetics, University of Minnesota, Minneapolis, Minnesota, United States of America
| | - Timothy J. Ebner
- Department of Neuroscience, University of Minnesota, Minneapolis, Minnesota, United States of America
| | - Maurice S. Swanson
- Department of Molecular Genetics and Microbiology, University of Florida, Gainesville, Florida, United States of America
- Genetics Institute, University of Florida, Gainesville, Florida, United States of America
| | - Laura P. W. Ranum
- Department of Genetics, Cell Biology, and Development, University of Minnesota, Minneapolis, Minnesota, United States of America
- Institute of Human Genetics, University of Minnesota, Minneapolis, Minnesota, United States of America
- * E-mail:
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Krueger KAD, Tsuji S, Fukuda Y, Takahashi Y, Goto J, Mitsui J, Ishiura H, Dalton JC, Miller MB, Day JW, Ranum LPW. SNP haplotype mapping in a small ALS family. PLoS One 2009; 4:e5687. [PMID: 19479031 PMCID: PMC2682655 DOI: 10.1371/journal.pone.0005687] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [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: 10/30/2008] [Accepted: 04/27/2009] [Indexed: 12/12/2022] Open
Abstract
The identification of genes for monogenic disorders has proven to be highly effective for understanding disease mechanisms, pathways and gene function in humans. Nevertheless, while thousands of Mendelian disorders have not yet been mapped there has been a trend away from studying single-gene disorders. In part, this is due to the fact that many of the remaining single-gene families are not large enough to map the disease locus to a single site in the genome. New tools and approaches are needed to allow researchers to effectively tap into this genetic gold-mine. Towards this goal, we have used haploid cell lines to experimentally validate the use of high-density single nucleotide polymorphism (SNP) arrays to define genome-wide haplotypes and candidate regions, using a small amyotrophic lateral sclerosis (ALS) family as a prototype. Specifically, we used haploid-cell lines to determine if high-density SNP arrays accurately predict haplotypes across entire chromosomes and show that haplotype information significantly enhances the genetic information in small families. Panels of haploid-cell lines were generated and a 5 centimorgan (cM) short tandem repeat polymorphism (STRP) genome scan was performed. Experimentally derived haplotypes for entire chromosomes were used to directly identify regions of the genome identical-by-descent in 5 affected individuals. Comparisons between experimentally determined and in silico haplotypes predicted from SNP arrays demonstrate that SNP analysis of diploid DNA accurately predicted chromosomal haplotypes. These methods precisely identified 12 candidate intervals, which are shared by all 5 affected individuals. Our study illustrates how genetic information can be maximized using readily available tools as a first step in mapping single-gene disorders in small families.
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Affiliation(s)
- Katherine A. Dick Krueger
- Departments of Genetics, Cell Biology and Development, University of Minnesota, Minneapolis, Minnesota, United States of America
- Institute of Human Genetics, University of Minnesota, Minneapolis, Minnesota, United States of America
| | - Shoji Tsuji
- Department of Neurology, The University of Tokyo, Tokyo, Japan
| | - Yoko Fukuda
- Department of Neurology, The University of Tokyo, Tokyo, Japan
| | - Yuji Takahashi
- Department of Neurology, The University of Tokyo, Tokyo, Japan
| | - Jun Goto
- Department of Neurology, The University of Tokyo, Tokyo, Japan
| | - Jun Mitsui
- Department of Neurology, The University of Tokyo, Tokyo, Japan
| | | | - Joline C. Dalton
- Departments of Genetics, Cell Biology and Development, University of Minnesota, Minneapolis, Minnesota, United States of America
- Institute of Human Genetics, University of Minnesota, Minneapolis, Minnesota, United States of America
| | - Michael B. Miller
- Epidemiology and Community Health, University of Minnesota, Minneapolis, Minnesota, United States of America
| | - John W. Day
- Institute of Human Genetics, University of Minnesota, Minneapolis, Minnesota, United States of America
- Department of Neurology, University of Minnesota, Minneapolis, Minnesota, United States of America
| | - Laura P. W. Ranum
- Departments of Genetics, Cell Biology and Development, University of Minnesota, Minneapolis, Minnesota, United States of America
- Institute of Human Genetics, University of Minnesota, Minneapolis, Minnesota, United States of America
- * E-mail:
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Abstract
Spinocerebellar ataxia type 8 (SCA8) is a dominantly inherited, slowly progressive neurodegenerative disorder caused by a CTG.CAG repeat expansion located on chromosome 13q21. The expansion mutation was isolated directly from the DNA of a single patient using RAPID cloning and subsequently shown to co-segregate with disease in additional ataxia families including a seven-generation kindred (the MN-A family). The size-dependent penetrance of the repeat found in the large MN-A kindred makes it appear as though some parts of the family have a dominant disorder while other parts of this same family have recessive or sporadic forms of ataxia. While the linkage and size-dependent penetrance of the SCA8 CTG.CAG expansion in the MN-A family argue that the SCA8 expansion causes ataxia, the reduced penetrance in other SCA8 families and the discovery of expansions in the general population have led to a controversy surrounding whether or not the SCA8 expansion is pathogenic. A recently reported mouse model in which SCA8 BAC-expansion but not BAC-control lines develop a progressive neurological phenotype now demonstrates the pathogenicity of the (CTG.CAG)(n) expansion. These mice show a loss of cerebellar GABAergic inhibition and, similar to human patients, have 1C2-positive intranuclear inclusions in Purkinje cells and other neurons. Additional studies demonstrate that the SCA8 expansion is expressed in both directions (CUG and CAG) and that a novel gene expressed in the CAG direction encodes a pure polyglutamine expansion protein (ataxin 8, ATXN8). Moreover, the expression of non-coding (CUG)(n) expansion transcripts (ataxin 8 opposite strand, ATXN8OS) and the discovery of intranuclear polyglutamine inclusions suggest SCA8 pathogenesis may involve toxic gain-of-function mechanisms at both the protein and RNA levels. Our data, combined with the recently reported antisense transcripts spanning the DM1 repeat expansion in the CAG direction and the growing number of reports of antisense transcripts expressed throughout the mammalian genome, raises the possibility that bidirectional expression across pathogenic microsatellite expansions may occur in other expansion disorders, and that potential pathogenic effects of mutations expressed from both strands should be considered.
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Affiliation(s)
- Yoshio Ikeda
- Department of Genetics, Cell Biology, and Development, University of Minnesota, Minneapolis, MN 55455, USA
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Martins S, Calafell F, Gaspar C, Wong VCN, Silveira I, Nicholson GA, Brunt ER, Tranebjaerg L, Stevanin G, Hsieh M, Soong BW, Loureiro L, Dürr A, Tsuji S, Watanabe M, Jardim LB, Giunti P, Riess O, Ranum LPW, Brice A, Rouleau GA, Coutinho P, Amorim A, Sequeiros J. Asian Origin for the Worldwide-Spread Mutational Event in Machado-Joseph Disease. ACTA ACUST UNITED AC 2007; 64:1502-8. [DOI: 10.1001/archneur.64.10.1502] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
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Lorenzo DN, Forrest SM, Ikeda Y, Dick KA, Ranum LPW, Knight MA. Spinocerebellar ataxia type 20 is genetically distinct from spinocerebellar ataxia type 5. Neurology 2006; 67:2084-5. [PMID: 17159129 DOI: 10.1212/01.wnl.0000247662.05197.59] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Affiliation(s)
- D N Lorenzo
- Department of Genetics, Cell Biology, and Development, University of Minnesota, Minneapolis, MN 55455, USA
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Abstract
Myotonic dystrophy type 1 (DM1) is caused by a CTG expansion mutation located in the 3' untranslated portion of the dystrophica myotonin protein kinase gene. The identification and characterization of RNA-binding proteins that interact with expanded CUG repeats and the discovery that a similar transcribed but untranslated CCTG expansion in an intron causes myotonic dystrophy type 2 (DM2) have uncovered a new type of mechanism in which microsatellite expansion mutations cause disease through an RNA gain-of-function mechanism. This review discusses RNA pathogenesis in DM1 and DM2 and evidence that similar mechanisms may play a role in a growing number of dominant noncoding expansion disorders, including fragile X tremor ataxia syndrome (FXTAS), spinocerebellar ataxia type 8 (SCA8), SCA10, SCA12, and Huntington's disease-like 2 (HDL2).
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Affiliation(s)
- Laura P W Ranum
- Institute of Human Genetics and Department of Genetics, Cell Biology & Development, University of Minnesota, Minneapolis, Minnesota 55455, USA.
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Moseley ML, Zu T, Ikeda Y, Gao W, Mosemiller AK, Daughters RS, Chen G, Weatherspoon MR, Clark HB, Ebner TJ, Day JW, Ranum LPW. Bidirectional expression of CUG and CAG expansion transcripts and intranuclear polyglutamine inclusions in spinocerebellar ataxia type 8. Nat Genet 2006; 38:758-69. [PMID: 16804541 DOI: 10.1038/ng1827] [Citation(s) in RCA: 314] [Impact Index Per Article: 17.4] [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: 01/09/2006] [Accepted: 05/22/2006] [Indexed: 11/08/2022]
Abstract
We previously reported that a (CTG)n expansion causes spinocerebellar ataxia type 8 (SCA8), a slowly progressive ataxia with reduced penetrance. We now report a transgenic mouse model in which the full-length human SCA8 mutation is transcribed using its endogenous promoter. (CTG)116 expansion, but not (CTG)11 control lines, develop a progressive neurological phenotype with in vivo imaging showing reduced cerebellar-cortical inhibition. 1C2-positive intranuclear inclusions in cerebellar Purkinje and brainstem neurons in SCA8 expansion mice and human SCA8 autopsy tissue result from translation of a polyglutamine protein, encoded on a previously unidentified antiparallel transcript (ataxin 8, ATXN8) spanning the repeat in the CAG direction. The neurological phenotype in SCA8 BAC expansion but not BAC control lines demonstrates the pathogenicity of the (CTG-CAG)n expansion. Moreover, the expression of noncoding (CUG)n expansion transcripts (ataxin 8 opposite strand, ATXN8OS) and the discovery of intranuclear polyglutamine inclusions suggests SCA8 pathogenesis involves toxic gain-of-function mechanisms at both the protein and RNA levels.
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Affiliation(s)
- Melinda L Moseley
- Department of Genetics, Cell Biology, and Development, University of Minnesota, Minneapolis, Minnesota 55455, USA
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Udd B, Meola G, Krahe R, Thornton C, Ranum LPW, Bassez G, Kress W, Schoser B, Moxley R. 140th ENMC International Workshop: Myotonic Dystrophy DM2/PROMM and other myotonic dystrophies with guidelines on management. Neuromuscul Disord 2006; 16:403-13. [PMID: 16684600 DOI: 10.1016/j.nmd.2006.03.010] [Citation(s) in RCA: 62] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2006] [Revised: 03/09/2006] [Accepted: 03/16/2006] [Indexed: 10/24/2022]
Affiliation(s)
- B Udd
- Neurology Department, Tampere University Hospital and Tampere Medical School, Finland.
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Margolis JM, Schoser BG, Moseley ML, Day JW, Ranum LPW. DM2 intronic expansions: evidence for CCUG accumulation without flanking sequence or effects on ZNF9 mRNA processing or protein expression. Hum Mol Genet 2006; 15:1808-15. [PMID: 16624843 DOI: 10.1093/hmg/ddl103] [Citation(s) in RCA: 92] [Impact Index Per Article: 5.1] [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] [Indexed: 11/12/2022] Open
Abstract
Myotonic dystrophy type 2 (DM2) is caused by a CCTG expansion mutation in intron 1 of the zinc finger protein 9 (ZNF9) gene. The mean expansion size in patients is larger than for DM1 or any previously reported disorder (mean=5000 CCTGs; range=75-11 000), and similar to DM1, repeats containing ribonuclear inclusions accumulate in affected DM2 tissue. Although an RNA gain-of-function mechanism involving DM1 CUG or DM2 CCUG expansion transcripts is now well established, still debated are the potential role that flanking sequences within the DMPK 3'-UTR may have on disease pathogenesis and whether or not decreased expression of DMPK, ZNF9 or neighboring genes at these loci contribute to disease. To address these questions in DM2, we have examined the nucleic acid content of the ribonuclear inclusions and the effects of these large expansions on ZNF9 expression. Using cell lines either haploid or homozygous for the expansion, as well as skeletal muscle biopsy tissue, we demonstrate that pre-mRNAs containing large CCUG expansions are normally spliced and exported from the nucleus, that the expansions do not decrease ZNF9 expression at the mRNA or protein level, and that the ribonuclear inclusions are enriched for the CCUG expansion, but not intronic flanking sequences. These data suggest that the downstream molecular effects of the DM2 mutation are triggered by the accumulation of CCUG repeat tract alone.
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Affiliation(s)
- Jamie M Margolis
- Department of Genetics, Cell Biology and Development, University of Minnesota, 420 Delaware Street SE, Minneapolis, MN 55455, USA
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Chen DH, Cimino PJ, Ranum LPW, Zoghbi HY, Yabe I, Schut L, Margolis RL, Lipe HP, Feleke A, Matsushita M, Wolff J, Morgan C, Lau D, Fernandez M, Sasaki H, Raskind WH, Bird TD. The clinical and genetic spectrum of spinocerebellar ataxia 14. Neurology 2006; 64:1258-60. [PMID: 15824357 DOI: 10.1212/01.wnl.0000156801.64549.6b] [Citation(s) in RCA: 66] [Impact Index Per Article: 3.7] [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] [Indexed: 11/15/2022] Open
Abstract
Spinocerebellar ataxia 14 (SCA14) is associated with missense mutations in the protein kinase C gamma gene (PRKCG), rather than a nucleotide repeat expansion. In this large-scale study of PRKCG in patients with ataxia, two new missense mutations, an in-frame deletion, and a possible splice site mutation were found and can now be added to the four previously described missense mutations. The genotype/phenotype correlations in these families are described.
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Affiliation(s)
- D-H Chen
- Departments of Neurology, University of Washington, Seattle, USA
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Meisler MH, Trudeau MM, Dalton JC, Day JW, Ranum LPW. Gene symbol: SCN8A. Disease: Ataxia. Accession #Hd0520. Hum Genet 2006; 118:776. [PMID: 17297687] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Affiliation(s)
- M H Meisler
- Department of Human Genetics, University of Michigan, 4909 Buhl, Box 0618, Ann Arbor, MI 48109-0618, USA.
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Ikeda Y, Dick KA, Weatherspoon MR, Gincel D, Armbrust KR, Dalton JC, Stevanin G, Dürr A, Zühlke C, Bürk K, Clark HB, Brice A, Rothstein JD, Schut LJ, Day JW, Ranum LPW. Spectrin mutations cause spinocerebellar ataxia type 5. Nat Genet 2006; 38:184-90. [PMID: 16429157 DOI: 10.1038/ng1728] [Citation(s) in RCA: 267] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2005] [Accepted: 11/29/2005] [Indexed: 11/09/2022]
Abstract
We have discovered that beta-III spectrin (SPTBN2) mutations cause spinocerebellar ataxia type 5 (SCA5) in an 11-generation American kindred descended from President Lincoln's grandparents and two additional families. Two families have separate in-frame deletions of 39 and 15 bp, and a third family has a mutation in the actin/ARP1 binding region. Beta-III spectrin is highly expressed in Purkinje cells and has been shown to stabilize the glutamate transporter EAAT4 at the surface of the plasma membrane. We found marked differences in EAAT4 and GluRdelta2 by protein blot and cell fractionation in SCA5 autopsy tissue. Cell culture studies demonstrate that wild-type but not mutant beta-III spectrin stabilizes EAAT4 at the plasma membrane. Spectrin mutations are a previously unknown cause of ataxia and neurodegenerative disease that affect membrane proteins involved in glutamate signaling.
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Affiliation(s)
- Yoshio Ikeda
- Department of Genetics, Cell Biology, and Development, University of Minnesota, 321 Church St. SE, Minneapolis, Minnesota 55455 USA
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Abstract
The general model that dominant diseases are caused by mutations that result in a gain or change in function of the corresponding protein was challenged by the discovery that the myotonic dystrophy type 1 mutation is a CTG expansion located in the 3' untranslated portion of a kinase gene. The subsequent discovery that a similar transcribed but untranslated CCTG expansion in an intron causes the same multisystemic features in myotonic dystrophy type 2 (DM2), along with other developments in the DM1 field, demonstrate a mechanism in which these expansion mutations cause disease through a gain of function mechanism triggered by the accumulation of transcripts containing CUG or CCUG repeat expansions. A similar RNA gain of function mechanism has also been implicated in fragile X tremor ataxia syndrome (FXTAS) and may play a role in pathogenesis of other non-coding repeat expansion diseases, including spinocerebellar ataxia type 8 (SCA8), SCA10, SCA12 and Huntington disease-like 2.
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Affiliation(s)
- K A Dick
- Department of Genetics, Cell Biology, and Development, University of Minnesota, Minneapolis, Minn., USA
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Trudeau MM, Dalton JC, Day JW, Ranum LPW, Meisler MH. Heterozygosity for a protein truncation mutation of sodium channel SCN8A in a patient with cerebellar atrophy, ataxia, and mental retardation. J Med Genet 2005; 43:527-30. [PMID: 16236810 PMCID: PMC2564538 DOI: 10.1136/jmg.2005.035667] [Citation(s) in RCA: 135] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
BACKGROUND The SCN8A gene on chromosome 12q13 encodes the voltage gated sodium channel Na(v)1.6, which is widely expressed in neurons of the CNS and PNS. Mutations in the mouse ortholog of SCN8A result in ataxia and other movement disorders. METHODS We screened the 26 coding exons of SCN8A in 151 patients with inherited or sporadic ataxia. RESULTS A 2 bp deletion in exon 24 was identified in a 9 year old boy with mental retardation, pancerebellar atrophy, and ataxia. This mutation, Pro1719ArgfsX6, introduces a translation termination codon into the pore loop of domain 4, resulting in removal of the C-terminal cytoplasmic domain and predicted loss of channel function. Three additional heterozygotes in the family exhibit milder cognitive and behavioural deficits including attention deficit hyperactivity disorder (ADHD). No additional occurrences of this mutation were observed in 625 unrelated DNA samples (1250 chromosomes). CONCLUSIONS The phenotypes of the heterozygous individuals suggest that mutations in SCN8A may result in motor and cognitive deficits of variable expressivity, but the study was limited by lack of segregation in the small pedigree and incomplete information about family members. Identification of additional families will be required to confirm the contribution of the SCN8A mutation to the clinical features in ataxia, cognition and behaviour disorders.
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Miller TM, Dias da Silva MR, Miller HA, Kwiecinski H, Mendell JR, Tawil R, McManis P, Griggs RC, Angelini C, Servidei S, Petajan J, Dalakas MC, Ranum LPW, Fu YH, Ptácek LJ. Correlating phenotype and genotype in the periodic paralyses. Neurology 2005; 63:1647-55. [PMID: 15534250 DOI: 10.1212/01.wnl.0000143383.91137.00] [Citation(s) in RCA: 178] [Impact Index Per Article: 9.4] [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] [Indexed: 11/15/2022] Open
Abstract
BACKGROUND Periodic paralyses and paramyotonia congenita are rare disorders causing disabling weakness and myotonia. Mutations in sodium, calcium, and potassium channels have been recognized as causing disease. OBJECTIVE To analyze the clinical phenotype of patients with and without discernible genotype and to identify other mutations in ion channel genes associated with disease. METHODS The authors have reviewed clinical data in patients with a diagnosis of hypokalemic periodic paralysis (56 kindreds, 71 patients), hyperkalemic periodic paralysis (47 kindreds, 99 patients), and paramyotonia congenita (24 kindreds, 56 patients). For those patients without one of the classically known mutations, the authors analyzed the entire coding region of the SCN4A, KCNE3, and KCNJ2 genes and portions of the coding region of the CACNA1S gene in order to identify new mutations. RESULTS Mutations were identified in approximately two thirds of kindreds with periodic paralysis or paramyotonia congenita. The authors found differences between the disorders and between those with and without identified mutations in terms of age at onset, frequency of attacks, duration of attacks, fixed proximal weakness, precipitants of attacks, myotonia, electrophysiologic studies, serum potassium levels, muscle biopsy, response to potassium administration, and response to treatment with acetazolamide. CONCLUSIONS Hypokalemic periodic paralysis, hyperkalemic periodic paralysis, and paramyotonia congenita may be distinguished based on clinical data. This series of 226 patients (127 kindreds) confirms some clinical features of this disorder with notable exceptions: In this series, patients without mutations had a less typical clinical presentation including an older age at onset, no changes in diet as a precipitant, and absence of vacuolar myopathy on muscle biopsy.
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Affiliation(s)
- T M Miller
- Department of Neurology, University of California San Francisco 94143-2922, USA
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Abstract
Myotonic dystrophy (dystrophia myotonica, DM) is the most common form of muscular dystrophy in adults. The presence of two genetic forms of this complex multisystemic disease (DM1 and DM2) was unrecognized until the genetic cause of DM1 was identified in 1992. The fact that the DM1 mutation is an untranslated CTG expansion led to extended controversy about the molecular pathophysiology of this disease. When the DM2 mutation was identified in 2001 as being a similarly untranslated CCTG expansion, the molecular and clinical parallels between DM1 and DM2 substantiated the role of a novel mechanism in generating the unusual constellation of clinical features seen in these diseases: the repeat expansions expressed at the RNA level alter RNA processing, at least in part by interfering with alternative splicing of other genes. For example, in both DM1 and DM2, altered splicing of chloride channel and insulin receptor transcripts leads to myotonia and insulin resistance, respectively. Although other mechanisms may underlie the differences between DM1 and DM2, the pathogenic effects of the RNA mechanism are now clear, which will facilitate development of appropriate treatments.
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Affiliation(s)
- John W Day
- Institute of Human Genetics, University of Minnesota, School of Medicine, Minneapolis, MN 55455, USA.
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