1
|
Mukherjee A, Pandey S. Tremor in Spinocerebellar Ataxia: A Scoping Review. Tremor Other Hyperkinet Mov (N Y) 2024; 14:31. [PMID: 38911333 PMCID: PMC11192095 DOI: 10.5334/tohm.911] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2024] [Accepted: 06/14/2024] [Indexed: 06/25/2024] Open
Abstract
Background Spinocerebellar ataxia (SCA) denotes an expanding list of autosomal dominant cerebellar ataxias. Although tremor is an important aspect of the clinical spectrum of the SCAs, its prevalence, phenomenology, and pathophysiology are unknown. Objectives This review aims to describe the various types of tremors seen in the different SCAs, with a discussion on the pathophysiology of the tremors, and the possible treatment modalities. Methods The authors conducted a literature search on PubMed using search terms including tremor and the various SCAs. Relevant articles were included in the review after excluding duplicate publications. Results While action (postural and intention) tremors are most frequently associated with SCA, rest and other rare tremors have also been documented. The prevalence and types of tremors vary among the different SCAs. SCA12, common in certain ethnic populations, presents a unique situation, where the tremor is typically the principal manifestation. Clinical manifestations of SCAs may be confused with essential tremor or Parkinson's disease. The pathophysiology of tremors in SCAs predominantly involves the cerebellum and its networks, especially the cerebello-thalamo-cortical circuit. Additionally, connections with the basal ganglia, and striatal dopaminergic dysfunction may have a role. Medical management of tremor is usually guided by the phenomenology and associated clinical features. Deep brain stimulation surgery may be helpful in treatment-resistant tremors. Conclusions Tremor is an elemental component of SCAs, with diverse phenomenology, and emphasizes the role of the cerebellum in tremor. Further studies will be useful to delineate the clinical, pathophysiological, and therapeutic aspects of tremor in SCAs.
Collapse
Affiliation(s)
- Adreesh Mukherjee
- Department of Neurology and Stroke Medicine, Amrita Hospital, Mata Amritanandamayi Marg Sector 88, Faridabad, Delhi National Capital Region, India
| | - Sanjay Pandey
- Department of Neurology and Stroke Medicine, Amrita Hospital, Mata Amritanandamayi Marg Sector 88, Faridabad, Delhi National Capital Region, India
| |
Collapse
|
2
|
Salari M, Etemadifar M, Rashedi R, Mardani S. A Review of Ocular Movement Abnormalities in Hereditary Cerebellar Ataxias. CEREBELLUM (LONDON, ENGLAND) 2024; 23:702-721. [PMID: 37000369 DOI: 10.1007/s12311-023-01554-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 03/21/2023] [Indexed: 04/01/2023]
Abstract
Cerebellar ataxias are a wide heterogeneous group of disorders that may present with fine motor deficits as well as gait and balance disturbances that have a significant influence on everyday activities. To review the ocular movements in cerebellar ataxias in order to improve the clinical knowledge of cerebellar ataxias and related subtypes. English papers published from January 1990 to May 2022 were selected by searching PubMed services. The main search keywords were ocular motor, oculomotor, eye movement, eye motility, and ocular motility, along with each ataxia subtype. The eligible papers were analyzed for clinical presentation, involved mutations, the underlying pathology, and ocular movement alterations. Forty-three subtypes of spinocerebellar ataxias and a number of autosomal dominant and autosomal recessive ataxias were discussed in terms of pathology, clinical manifestations, involved mutations, and with a focus on the ocular abnormalities. A flowchart has been made using ocular movement manifestations to differentiate different ataxia subtypes. And underlying pathology of each subtype is reviewed in form of illustrated models to reach a better understanding of each disorder.
Collapse
Affiliation(s)
- Mehri Salari
- Neurology Department, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Masoud Etemadifar
- Department of Functional Neurosurgery, Medical School, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Ronak Rashedi
- Neurology Department, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
| | - Sayna Mardani
- Neurology Department, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| |
Collapse
|
3
|
Atang AE, Keller AR, Denha SA, Avery AW. Increased Actin Binding Is a Shared Molecular Consequence of Numerous SCA5 Mutations in β-III-Spectrin. Cells 2023; 12:2100. [PMID: 37626910 PMCID: PMC10453832 DOI: 10.3390/cells12162100] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2023] [Revised: 07/28/2023] [Accepted: 08/14/2023] [Indexed: 08/27/2023] Open
Abstract
Spinocerebellar ataxia type 5 (SCA5) is a neurodegenerative disease caused by mutations in the SPTBN2 gene encoding the cytoskeletal protein β-III-spectrin. Previously, we demonstrated that a L253P missense mutation, localizing to the β-III-spectrin actin-binding domain (ABD), causes increased actin-binding affinity. Here we investigate the molecular consequences of nine additional ABD-localized, SCA5 missense mutations: V58M, K61E, T62I, K65E, F160C, D255G, T271I, Y272H, and H278R. We show that all of the mutations, similar to L253P, are positioned at or near the interface of the two calponin homology subdomains (CH1 and CH2) comprising the ABD. Using biochemical and biophysical approaches, we demonstrate that the mutant ABD proteins can attain a well-folded state. However, thermal denaturation studies show that all nine mutations are destabilizing, suggesting a structural disruption at the CH1-CH2 interface. Importantly, all nine mutations cause increased actin binding. The mutant actin-binding affinities vary greatly, and none of the nine mutations increase actin-binding affinity as much as L253P. ABD mutations causing high-affinity actin binding, with the notable exception of L253P, appear to be associated with an early age of symptom onset. Altogether, the data indicate that increased actin-binding affinity is a shared molecular consequence of numerous SCA5 mutations, which has important therapeutic implications.
Collapse
Affiliation(s)
| | | | | | - Adam W. Avery
- Department of Chemistry, Oakland University, Rochester, MI 48309, USA
| |
Collapse
|
4
|
Atang AE, Keller AR, Denha SA, Avery AW. Increased actin binding is a shared molecular consequence of numerous spinocerebellar ataxia mutations in β-III-spectrin. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.02.20.529285. [PMID: 36865188 PMCID: PMC9980045 DOI: 10.1101/2023.02.20.529285] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/23/2023]
Abstract
Spinocerebellar ataxia type 5 (SCA5) is a neurodegenerative disease caused by mutations in the SPTBN2 gene encoding the cytoskeletal protein β-III-spectrin. Previously, we demonstrated that a L253P missense mutation, localizing to the β-III-spectrin actin-binding domain (ABD), causes increased actin-binding affinity. Here we investigate the molecular consequences of nine additional ABD-localized, SCA5 missense mutations: V58M, K61E, T62I, K65E, F160C, D255G, T271I, Y272H, and H278R. We show that all of the mutations, similar to L253P, are positioned at or near the interface of the two calponin homology subdomains (CH1 and CH2) comprising the ABD. Using biochemical and biophysical approaches, we demonstrate that the mutant ABD proteins can attain a well-folded state. However, thermal denaturation studies show that all nine mutations are destabilizing, suggesting a structural disruption at the CH1-CH2 interface. Importantly, all nine mutations cause increased actin binding. The mutant actin-binding affinities vary greatly, and none of the nine mutations increase actin-binding affinity as much as L253P. ABD mutations causing high-affinity actin binding, with the notable exception of L253P, appear to be associated with early age of symptom onset. Altogether, the data indicate increased actin-binding affinity is a shared molecular consequence of numerous SCA5 mutations, which has important therapeutic implications.
Collapse
Affiliation(s)
| | - Amanda R. Keller
- Department of Chemistry, Oakland University, Rochester, MI 48309, USA
| | - Sarah A. Denha
- Department of Chemistry, Oakland University, Rochester, MI 48309, USA
| | - Adam W. Avery
- Department of Chemistry, Oakland University, Rochester, MI 48309, USA
| |
Collapse
|
5
|
Lorenzo DN, Edwards RJ, Slavutsky AL. Spectrins: molecular organizers and targets of neurological disorders. Nat Rev Neurosci 2023; 24:195-212. [PMID: 36697767 PMCID: PMC10598481 DOI: 10.1038/s41583-022-00674-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/22/2022] [Indexed: 01/26/2023]
Abstract
Spectrins are cytoskeletal proteins that are expressed ubiquitously in the mammalian nervous system. Pathogenic variants in SPTAN1, SPTBN1, SPTBN2 and SPTBN4, four of the six genes encoding neuronal spectrins, cause neurological disorders. Despite their structural similarity and shared role as molecular organizers at the cell membrane, spectrins vary in expression, subcellular localization and specialization in neurons, and this variation partly underlies non-overlapping disease presentations across spectrinopathies. Here, we summarize recent progress in discerning the local and long-range organization and diverse functions of neuronal spectrins. We provide an overview of functional studies using mouse models, which, together with growing human genetic and clinical data, are helping to illuminate the aetiology of neurological spectrinopathies. These approaches are all critical on the path to plausible therapeutic solutions.
Collapse
Affiliation(s)
- Damaris N Lorenzo
- Department of Cell and Developmental Biology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA.
- Department of Cell Biology and Physiology, The University of North Carolina at Chapel Hill, Chapel Hill, NC, USA.
| | - Reginald J Edwards
- Department of Cell Biology and Physiology, The University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Anastasia L Slavutsky
- Department of Cell and Developmental Biology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| |
Collapse
|
6
|
Lee SU, Kim JS, Yoo D, Kim A, Kim HJ, Choi JY, Park JY, Jeong SH, Kim JM, Park KW. Ocular Motor Findings Aid in Differentiation of Spinocerebellar Ataxia Type 17 from Huntington's Disease. CEREBELLUM (LONDON, ENGLAND) 2023; 22:1-13. [PMID: 34993890 DOI: 10.1007/s12311-021-01356-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 12/02/2021] [Indexed: 02/01/2023]
Abstract
Differentiation of spinocerebellar ataxia type 17 (SCA17) from Huntington's disease (HD) is often challenging since they share the clinical features of chorea, parkinsonism, and dystonia. The ocular motor findings remain to be elucidated in SCA17, and may help differentiating SCA17 from HD. We retrospectively compared the ocular motor findings of 11 patients with SCA17 with those of 10 patients with HD. In SCA17, abnormal ocular motor findings included impaired smooth pursuit (9/11, 82%), dysmetric saccades (9/11, 82%), central positional nystagmus (CPN, 7/11, 64%), abnormal head-impulse tests (4/11, 36%), and horizontal gaze-evoked nystagmus (GEN, 3/11, 27%). Among these, CPN was more frequently observed in SCA17 than in HD (7/11 (64%) vs. 0/10 (0%), p = 0.004) while saccadic slowing was more frequently observed in HD than in SCA17 (8/10 (80%) vs. 2/11 (18%), p = 0.009). Of six patients with follow-up evaluation, five later developed bilateral saccadic hypermetria (n = 4), GEN (n = 1), CPN (n = 1), bilaterally abnormal smooth pursuit (n = 1), and hyperactive head-impulse responses (n = 1) along with a clinical decline. Ocular motor abnormalities can be utilized as a diagnostic marker for differentiation of SCA17 from HD as well as a surrogate marker for clinical decline in SCA17.
Collapse
Affiliation(s)
- Sun-Uk Lee
- Department of Neurology, Korea University Medical Center, Seoul, Republic of Korea.,Department of Neurology, Seoul National University College of Medicine, 173-82 Gumi-ro, Bundang-gu, Seongnam, Gyeonggi-do, 13620, Republic of Korea
| | - Ji-Soo Kim
- Department of Neurology, Seoul National University College of Medicine, 173-82 Gumi-ro, Bundang-gu, Seongnam, Gyeonggi-do, 13620, Republic of Korea. .,Clinical Neuroscience Center, Dizziness Center, and Department of Neurology, Seoul National University Bundang Hospital, Seongnam, Republic of Korea.
| | - Dallah Yoo
- Department of Neurology, Seoul National University College of Medicine, 173-82 Gumi-ro, Bundang-gu, Seongnam, Gyeonggi-do, 13620, Republic of Korea.,Movement Disorder Center, Department of Neurology, Kyung Hee University Hospital, Gangdong-gu, Republic of Korea
| | - Aryun Kim
- Department of Neurology, Chungbuk National University Hospital, Cheongju, Republic of Korea
| | - Hyo-Jung Kim
- Research Administration Team, Seoul National University Bundang Hospital, Seongnam, Republic of Korea
| | - Jeong-Yoon Choi
- Department of Neurology, Seoul National University College of Medicine, 173-82 Gumi-ro, Bundang-gu, Seongnam, Gyeonggi-do, 13620, Republic of Korea.,Clinical Neuroscience Center, Dizziness Center, and Department of Neurology, Seoul National University Bundang Hospital, Seongnam, Republic of Korea
| | - Ji-Yun Park
- Deparment of Neurology, Ulsan University Hospital, Ulsan University College of Medicine, Ulsan, Republic of Korea
| | - Seong-Hae Jeong
- Department of Neurology, Chungnam National University Hospital, Chungnam National University School of Medicine, Daejeon, Republic of Korea
| | - Jong-Min Kim
- Department of Neurology, Seoul National University College of Medicine, 173-82 Gumi-ro, Bundang-gu, Seongnam, Gyeonggi-do, 13620, Republic of Korea.,Clinical Neuroscience Center, Dizziness Center, and Department of Neurology, Seoul National University Bundang Hospital, Seongnam, Republic of Korea
| | - Kun-Woo Park
- Department of Neurology, Korea University Medical Center, Seoul, Republic of Korea
| |
Collapse
|
7
|
Younger DS. Neurogenetic motor disorders. HANDBOOK OF CLINICAL NEUROLOGY 2023; 195:183-250. [PMID: 37562870 DOI: 10.1016/b978-0-323-98818-6.00003-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/12/2023]
Abstract
Advances in the field of neurogenetics have practical applications in rapid diagnosis on blood and body fluids to extract DNA, obviating the need for invasive investigations. The ability to obtain a presymptomatic diagnosis through genetic screening and biomarkers can be a guide to life-saving disease-modifying therapy or enzyme replacement therapy to compensate for the deficient disease-causing enzyme. The benefits of a comprehensive neurogenetic evaluation extend to family members in whom identification of the causal gene defect ensures carrier detection and at-risk counseling for future generations. This chapter explores the many facets of the neurogenetic evaluation in adult and pediatric motor disorders as a primer for later chapters in this volume and a roadmap for the future applications of genetics in neurology.
Collapse
Affiliation(s)
- David S Younger
- Department of Clinical Medicine and Neuroscience, CUNY School of Medicine, New York, NY, United States; Department of Medicine, Section of Internal Medicine and Neurology, White Plains Hospital, White Plains, NY, United States.
| |
Collapse
|
8
|
Denha SA, Atang AE, Hays TS, Avery AW. β-III-spectrin N-terminus is required for high-affinity actin binding and SCA5 neurotoxicity. Sci Rep 2022; 12:1726. [PMID: 35110634 PMCID: PMC8810934 DOI: 10.1038/s41598-022-05762-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2021] [Accepted: 01/17/2022] [Indexed: 11/09/2022] Open
Abstract
Recent structural studies of β-III-spectrin and related cytoskeletal proteins revealed N-terminal sequences that directly bind actin. These sequences are variable in structure, and immediately precede a conserved actin-binding domain composed of tandem calponin homology domains (CH1 and CH2). Here we investigated in Drosophila the significance of the β-spectrin N-terminus, and explored its functional interaction with a CH2-localized L253P mutation that underlies the neurodegenerative disease spinocerebellar ataxia type 5 (SCA5). We report that pan-neuronal expression of an N-terminally truncated β-spectrin fails to rescue lethality resulting from a β-spectrin loss-of-function allele, indicating that the N-terminus is essential to β-spectrin function in vivo. Significantly, N-terminal truncation rescues neurotoxicity and defects in dendritic arborization caused by L253P. In vitro studies show that N-terminal truncation eliminates L253P-induced high-affinity actin binding, providing a mechanistic basis for rescue. These data suggest that N-terminal sequences may be useful therapeutic targets for small molecule modulation of the aberrant actin binding associated with SCA5 β-spectrin and spectrin-related disease proteins.
Collapse
Affiliation(s)
- Sarah A Denha
- Department of Chemistry, Oakland University, Rochester, MI, USA
| | | | - Thomas S Hays
- Department of Genetics, Cell Biology and Development, University of Minnesota, Minneapolis, MN, USA
| | - Adam W Avery
- Department of Chemistry, Oakland University, Rochester, MI, USA. .,Department of Genetics, Cell Biology and Development, University of Minnesota, Minneapolis, MN, USA.
| |
Collapse
|
9
|
Corral-Juan M, Casquero P, Giraldo-Restrepo N, Laurie S, Martinez-Piñeiro A, Mateo-Montero RC, Ispierto L, Vilas D, Tolosa E, Volpini V, Alvarez-Ramo R, Sánchez I, Matilla-Dueñas A. OUP accepted manuscript. Brain Commun 2022; 4:fcac030. [PMID: 35310830 PMCID: PMC8928420 DOI: 10.1093/braincomms/fcac030] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2021] [Revised: 10/20/2021] [Accepted: 02/08/2022] [Indexed: 11/18/2022] Open
Abstract
Spinocerebellar ataxias consist of a highly heterogeneous group of inherited movement disorders clinically characterized by progressive cerebellar ataxia variably associated with additional distinctive clinical signs. The genetic heterogeneity is evidenced by the myriad of associated genes and underlying genetic defects identified. In this study, we describe a new spinocerebellar ataxia subtype in nine members of a Spanish five-generation family from Menorca with affected individuals variably presenting with ataxia, nystagmus, dysarthria, polyneuropathy, pyramidal signs, cerebellar atrophy and distinctive cerebral demyelination. Affected individuals presented with horizontal and vertical gaze-evoked nystagmus and hyperreflexia as initial clinical signs, and a variable age of onset ranging from 12 to 60 years. Neurophysiological studies showed moderate axonal sensory polyneuropathy with altered sympathetic skin response predominantly in the lower limbs. We identified the c.1877C > T (p.Ser626Leu) pathogenic variant within the SAMD9L gene as the disease causative genetic defect with a significant log-odds score (Zmax = 3.43; θ = 0.00; P < 3.53 × 10−5). We demonstrate the mitochondrial location of human SAMD9L protein, and its decreased levels in patients’ fibroblasts in addition to mitochondrial perturbations. Furthermore, mutant SAMD9L in zebrafish impaired mobility and vestibular/sensory functions. This study describes a novel spinocerebellar ataxia subtype caused by SAMD9L mutation, SCA49, which triggers mitochondrial alterations pointing to a role of SAMD9L in neurological motor and sensory functions.
Collapse
Affiliation(s)
- Marc Corral-Juan
- Functional and Translational Neurogenetics Unit, Department of Neuroscience, Research Institute Germans Trias i Pujol (IGTP), Universitat Autònoma de Barcelona-Can Ruti Campus, Badalona, Barcelona, Spain
| | - Pilar Casquero
- Neurology and Neurophysiology Section, Hospital Mateu Orfila, Mahón, Menorca, Spain
| | | | - Steve Laurie
- Centro Nacional de Análisis Genómico (CNAG-CRG), Center for Genomic Regulation, Barcelona Institute of Science and Technology (BIST), Barcelona, Spain
| | - Alicia Martinez-Piñeiro
- Neuromuscular and Functional Studies Unit, Neurology Service, University Hospital Germans Trias i Pujol (HUGTiP), Universitat Autònoma de Barcelona-Can Ruti Campus, Badalona, Barcelona, Spain
| | | | - Lourdes Ispierto
- Neurodegenerative Diseases Unit, Neurology Service, Department of Neuroscience, University Hospital Germans Trias i Pujol (HUGTiP), Universitat Autònoma de Barcelona-Can Ruti Campus, Badalona, Barcelona, Spain
| | - Dolores Vilas
- Neurodegenerative Diseases Unit, Neurology Service, Department of Neuroscience, University Hospital Germans Trias i Pujol (HUGTiP), Universitat Autònoma de Barcelona-Can Ruti Campus, Badalona, Barcelona, Spain
- Parkinson Disease and Movement Disorders Unit, Neurology Service, Hospital Clínic de Barcelona, Institut d’Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), University of Barcelona (UB), Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED: CB06/05/0018-ISCIII), Barcelona, Spain
| | - Eduardo Tolosa
- Parkinson Disease and Movement Disorders Unit, Neurology Service, Hospital Clínic de Barcelona, Institut d’Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), University of Barcelona (UB), Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED: CB06/05/0018-ISCIII), Barcelona, Spain
| | | | - Ramiro Alvarez-Ramo
- Neurodegenerative Diseases Unit, Neurology Service, Department of Neuroscience, University Hospital Germans Trias i Pujol (HUGTiP), Universitat Autònoma de Barcelona-Can Ruti Campus, Badalona, Barcelona, Spain
| | - Ivelisse Sánchez
- Functional and Translational Neurogenetics Unit, Department of Neuroscience, 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, Research Institute Germans Trias i Pujol (IGTP), Universitat Autònoma de Barcelona-Can Ruti Campus, Badalona, Barcelona, Spain
- Correspondence to: Dr Antoni Matilla-Dueñas Head of the Neurogenetics Unit Health Sciences Research Institute Germans Trias i Pujol (IGTP) Ctra. de Can Ruti, Camí de les Escoles s/n 08916 Badalona, Barcelona, Spain E-mail:
| |
Collapse
|
10
|
Abstract
The term SCA refers to a phenotypically and genetically heterogeneous group of autosomal dominant spinocerebellar ataxias. Phenotypically they present as gait ataxia frequently in combination with dysarthria and oculomotor problems. Additional signs and symptoms are common and can include various pyramidal and extrapyramidal signs and intellectual impairment. Genetic causes of SCAs are either repeat expansions within disease genes or common mutations (point mutations, deletions, insertions etc.). Frequently the two types of mutations cause indistinguishable phenotypes (locus heterogeneity). This article focuses on SCAs caused by common mutations. It describes phenotype and genotype of the presently 27 types known and discusses the molecular pathogenesis in those 21 types where the disease gene has been identified. Apart from the dominant types, the article also summarizes findings in a variant caused by mutations in a mitochondrial gene. Possible common disease mechanisms are considered based on findings in the various SCAs described.
Collapse
Affiliation(s)
- Ulrich Müller
- Institute of Human Genetics, JLU-Gießen, Schlangenzahl 14, 35392, Giessen, Germany.
| |
Collapse
|
11
|
Louis ED, Faust PL. Essential Tremor Within the Broader Context of Other Forms of Cerebellar Degeneration. THE CEREBELLUM 2021; 19:879-896. [PMID: 32666285 DOI: 10.1007/s12311-020-01160-4] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Essential tremor (ET) has recently been reconceptualized by many as a degenerative disease of the cerebellum. Until now, though, there has been no attempt to frame it within the context of these diseases. Here, we compare the clinical and postmortem features of ET with other cerebellar degenerations, thereby placing it within the broader context of these diseases. Action tremor is the hallmark feature of ET. Although often underreported in the spinocerebellar ataxias (SCAs), action tremors occur, and it is noteworthy that in SCA12 and 15, they are highly prevalent, often severe, and can be the earliest disease manifestation, resulting in an initial diagnosis of ET in many cases. Intention tremor, sometimes referred to as "cerebellar tremor," is a common feature of ET and many SCAs. Other features of cerebellar dysfunction, gait ataxia and eye motion abnormalities, are seen to a mild degree in ET and more markedly in SCAs. Several SCAs (e.g., SCA5, 6, 14, and 15), like ET, follow a milder and more protracted disease course. In ET, numerous postmortem changes have been localized to the cerebellum and are largely confined to the cerebellar cortex, preserving the cerebellar nuclei. Purkinje cell loss is modest. Similarly, in SCA3, 12, and 15, Purkinje cell loss is limited, and in SCA12 and 15, there is preservation of cerebellar nuclei and relative sparing of other central nervous system regions. Both clinically and pathologically, there are numerous similarities and intersection points between ET and other disorders of cerebellar degeneration.
Collapse
Affiliation(s)
- Elan D Louis
- Department of Neurology and Therapeutics, University of Texas Southwestern Medical Center, Dallas, TX, USA.
| | - Phyllis L Faust
- Department of Pathology and Cell Biology, Columbia University Irving Medical Center and the New York Presbyterian Hospital, New York, NY, USA
| |
Collapse
|
12
|
Bian X, Wang S, Jin S, Xu S, Zhang H, Wang D, Shang W, Wang P. Two novel missense variants in SPTBN2 likely associated with spinocerebellar ataxia type 5. Neurol Sci 2021; 42:5195-5203. [PMID: 33797620 PMCID: PMC8642373 DOI: 10.1007/s10072-021-05204-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2020] [Accepted: 03/17/2021] [Indexed: 12/01/2022]
Abstract
INTRODUCTION Spinocerebellar ataxias (SCAs) are a heterozygous group of neurodegenerative disorders. Spinocerebellar ataxia type 5 (SCA5) is a rare autosomal-dominant ataxia with pure cerebellum involvement. The clinical characteristics are limb and gait ataxia, trunk ataxia, sensory deficits, abnormal eye movement, dysarthria, and hyperactive tendon reflexes. Spectrin beta nonerythrocytic 2 gene (SPTBN2), coding β-III spectrin protein, was identified to be associated with SCA5. To date, more than 19 variants of SPTBN2 have been reported. METHODS A family and an apparently sporadic patient with ataxia and cerebellar atrophy were recruited from Shandong Province (China). To discover the disease-causing variants, capillary electrophoresis and targeted next-generation sequencing were performed in the proband of the family and the sporadic patient. The candidate variants were verified by Sanger sequencing and analyzed by bioinformatics software. RESULTS In our study, we verified two novel heterozygous variants in SPTBN2 in a SCA pedigree and a sporadic patient. The proband of the pedigree and her mother presented with walking instability and progressively getting worse. The sporadic patient suffered from slurred speech, walking instability, and drinking water choking cough. MRI examination of the proband and sporadic patient both displayed moderate cerebellar atrophy. The variants identified were traditionally conserved and predicted probably damaging and disease-causing by bioinformatics analysis. CONCLUSION We identified two novel heterozygous variants of SPTBN2 resulting in severe ataxia which further delineated the correlation between the genotype and phenotype of SCA5, and pathogenesis of variants in SPTBN2 should be further researched.
Collapse
Affiliation(s)
- Xianli Bian
- Department of Neurology, The Second Hospital of Shandong University, Jinan, 250033, Shandong, China
| | - Shang Wang
- Department of Neurology, The Second Hospital of Shandong University, Jinan, 250033, Shandong, China
| | - Suqin Jin
- Department of Neurology, The Second Hospital of Shandong University, Jinan, 250033, Shandong, China
| | - Shunliang Xu
- Department of Neurology, The Second Hospital of Shandong University, Jinan, 250033, Shandong, China
| | - Hong Zhang
- Department of Neurology, The Second Hospital of Shandong University, Jinan, 250033, Shandong, China
| | - Dewei Wang
- Department of Neurology, The Second Hospital of Shandong University, Jinan, 250033, Shandong, China
| | - Wei Shang
- Department of Neurology, The Second Hospital of Shandong University, Jinan, 250033, Shandong, China
| | - Ping Wang
- Department of Neurology, The Second Hospital of Shandong University, Jinan, 250033, Shandong, China.
| |
Collapse
|
13
|
Romaniello R, Citterio A, Panzeri E, Arrigoni F, De Rinaldis M, Trabacca A, Bassi MT. Novel SPTBN2 gene mutation and first intragenic deletion in early onset spinocerebellar ataxia type 5. Ann Clin Transl Neurol 2021; 8:956-963. [PMID: 33756041 PMCID: PMC8045899 DOI: 10.1002/acn3.51345] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2021] [Revised: 03/03/2021] [Accepted: 03/03/2021] [Indexed: 01/09/2023] Open
Abstract
In the present study, we describe two novel cases of SCA5 with early onset. The first one, carrying a novel heterozygous de novo missense mutation in SPTBN2 gene, showed a striking very severe cerebellar atrophy and reduction of volume of the pons at a very young age (16 months). The latter, carrying the first de novo intragenic deletion so far reported in SPTBN2 gene, showed a mild cerebellar atrophy involving the hemispheres and a later onset. In both cases, for the first time, a hyperintense signal of the dentate nuclei was observed.
Collapse
Affiliation(s)
- Romina Romaniello
- Neuropsychiatry and Neurorehabilitation Unit, Scientific Institute, IRCCS Eugenio Medea, Bosisio Parini, Italy
| | - Andrea Citterio
- Laboratory of Molecular Biology, Scientific Institute, IRCCS Eugenio Medea, Bosisio Parini, Italy
| | - Elena Panzeri
- Laboratory of Molecular Biology, Scientific Institute, IRCCS Eugenio Medea, Bosisio Parini, Italy
| | - Filippo Arrigoni
- Neuroimaging Lab, Scientific Institute, IRCCS Eugenio Medea, Bosisio Parini, Lecco, Italy
| | - Marta De Rinaldis
- Unit for Severe Disabilities in Developmental Age and Young Adults, Scientific Institute, IRCCS E. Medea, Brindisi, Italy
| | - Antonio Trabacca
- Unit for Severe Disabilities in Developmental Age and Young Adults, Scientific Institute, IRCCS E. Medea, Brindisi, Italy
| | - Maria Teresa Bassi
- Laboratory of Molecular Biology, Scientific Institute, IRCCS Eugenio Medea, Bosisio Parini, Italy
| |
Collapse
|
14
|
Rebbeck RT, Andrick AK, Denha SA, Svensson B, Guhathakurta P, Thomas DD, Hays TS, Avery AW. Novel drug discovery platform for spinocerebellar ataxia, using fluorescence technology targeting β-III-spectrin. J Biol Chem 2021; 296:100215. [PMID: 33839680 PMCID: PMC7948455 DOI: 10.1074/jbc.ra120.015417] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2020] [Revised: 11/30/2020] [Accepted: 12/21/2020] [Indexed: 02/02/2023] Open
Abstract
Numerous diseases are linked to mutations in the actin-binding domains (ABDs) of conserved cytoskeletal proteins, including β-III-spectrin, α-actinin, filamin, and dystrophin. A β-III-spectrin ABD mutation (L253P) linked to spinocerebellar ataxia type 5 (SCA5) causes a dramatic increase in actin binding. Reducing actin binding of L253P is thus a potential therapeutic approach for SCA5 pathogenesis. Here, we validate a high-throughput screening (HTS) assay to discover potential disrupters of the interaction between the mutant β-III-spectrin ABD and actin in live cells. This assay monitors FRET between fluorescent proteins fused to the mutant ABD and the actin-binding peptide Lifeact, in HEK293-6E cells. Using a specific and high-affinity actin-binding tool compound, swinholide A, we demonstrate HTS compatibility with an excellent Z'-factor of 0.67 ± 0.03. Screening a library of 1280 pharmacologically active compounds in 1536-well plates to determine assay robustness, we demonstrate high reproducibility across plates and across days. We identified nine Hits that reduced FRET between Lifeact and ABD. Four of those Hits were found to reduce Lifeact cosedimentation with actin, thus establishing the potential of our assay for detection of actin-binding modulators. Concurrent to our primary FRET assay, we also developed a high-throughput compatible counter screen to remove undesirable FRET Hits. Using the FRET Hits, we show that our counter screen is sensitive to undesirable compounds that cause cell toxicity or ABD aggregation. Overall, our FRET-based HTS platform sets the stage to screen large compound libraries for modulators of β-III-spectrin, or disease-linked spectrin-related proteins, for therapeutic development.
Collapse
Affiliation(s)
- Robyn T Rebbeck
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, Minnesota, USA
| | - Anna K Andrick
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, Minnesota, USA
| | - Sarah A Denha
- Department of Chemistry, Oakland University, Rochester, Michigan, USA
| | - Bengt Svensson
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, Minnesota, USA
| | - Piyali Guhathakurta
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, Minnesota, USA
| | - David D Thomas
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, Minnesota, USA
| | - Thomas S Hays
- Department of Genetics, Cellular Biology, and Development, University of Minnesota, Minneapolis, Minnesota, USA
| | - Adam W Avery
- Department of Chemistry, Oakland University, Rochester, Michigan, USA; Department of Genetics, Cellular Biology, and Development, University of Minnesota, Minneapolis, Minnesota, USA.
| |
Collapse
|
15
|
Zonta A, Brussino A, Dentelli P, Brusco A. A novel case of congenital spinocerebellar ataxia 5: further support for a specific phenotype associated with the p.(Arg480Trp) variant in SPTBN2. BMJ Case Rep 2020; 13:13/12/e238108. [PMID: 33318253 PMCID: PMC7737026 DOI: 10.1136/bcr-2020-238108] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
A 4-year-old girl was referred to the geneticist with a history of ataxia associated with intention tremor of the hands, strabismus and hypermetropy. Her symptoms presented about 2 years earlier with inability to walk unaided and lower limbs hypotonia. Cognitive functions were normal. Brain MRI showed a cerebellar and vermian hypoplasia with enlargement of both the cerebrospinal fluid spaces and the IV brain ventricle. Family history was unremarkable. A genetic screening using a 42-gene panel for hereditary ataxia/spastic paraparesis identified a de novo c.1438C>T - p.(Arg480Trp) missense change in the SPTBN2 gene (NM_006946.2). This variant is reported to be associated with congenital ataxia, later evolving into ataxia and intellectual disability. This case further supports the existence of a specific SPTBN2 p.(Arg480Trp)-associated phenotype, with a de novo recurrence of this variant in the heterozygous state.
Collapse
Affiliation(s)
- Andrea Zonta
- Medical Genetics Unit, Città della Salute e della Scienza University Hospital, Torino, Italy
| | | | | | - Alfredo Brusco
- Medical Genetics Unit, Città della Salute e della Scienza University Hospital, Torino, Italy,Department Medical Sciences, University of Turin, Torino, Italy
| |
Collapse
|
16
|
Rosini F, Pretegiani E, Battisti C, Dotti MT, Federico A, Rufa A. Eye movement changes in autosomal dominant spinocerebellar ataxias. Neurol Sci 2020; 41:1719-1734. [PMID: 32130555 DOI: 10.1007/s10072-020-04318-4] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2019] [Accepted: 02/24/2020] [Indexed: 12/15/2022]
Abstract
Oculomotor abnormalities are common findings in spinocerebellar ataxias (SCAs), a clinically heterogeneous group of neurodegenerative disorders with an autosomal dominant pattern of inheritance. Usually, cerebellar impairment accounts for most of the eye movement changes encountered; as the disease progresses, the involvement of extracerebellar structures typically seen in later stages may modify the oculomotor progression. However, ocular movement changes are rarely specific. In this regard, some important exceptions include the prominent slowing of horizontal eye movements in SCA2 and, to a lesser extent, in SCA3, SCA4, and SCA28, or the executive deficit in SCA2 and SCA17. Here, we report the eye movement abnormalities and neurological pictures of SCAs through a review of the literature. Genetic and neuropathological/neuroimaging aspects are also briefly discussed. Overall, the findings reported indicate that oculomotor analysis could be of help in differential diagnosis among SCAs and contribute to clarify the role of brain structures, particularly the cerebellum, in oculomotor control.
Collapse
Affiliation(s)
- Francesca Rosini
- Department of Medicine Surgery and Neuroscience, Eye Tracking& Visual Application Lab EVALAB, Neurology and Neurometabolic Unit, University of Siena, Viale Bracci 2, 53100, Siena, Italy
| | - Elena Pretegiani
- Department of Medicine Surgery and Neuroscience, Eye Tracking& Visual Application Lab EVALAB, Neurology and Neurometabolic Unit, University of Siena, Viale Bracci 2, 53100, Siena, Italy
| | - Carla Battisti
- Department of Medicine, Surgery and Neuroscience, Neurology and Neurometabolic Unit, University of Siena, Siena, Italy
| | - Maria Teresa Dotti
- Department of Medicine, Surgery and Neuroscience, Neurology and Neurometabolic Unit, University of Siena, Siena, Italy
| | - Antonio Federico
- Department of Medicine, Surgery and Neuroscience, Neurology and Neurometabolic Unit, University of Siena, Siena, Italy
| | - Alessandra Rufa
- Department of Medicine Surgery and Neuroscience, Eye Tracking& Visual Application Lab EVALAB, Neurology and Neurometabolic Unit, University of Siena, Viale Bracci 2, 53100, Siena, Italy.
- Department of Medicine, Surgery and Neuroscience, Neurology and Neurometabolic Unit, University of Siena, Siena, Italy.
| |
Collapse
|
17
|
Lee SU, Kim JS, Kim HJ, Choi JY, Park JY, Kim JM, Yang X. Evolution of the vestibular function during head impulses in spinocerebellar ataxia type 6. J Neurol 2020; 267:1672-1678. [DOI: 10.1007/s00415-020-09756-w] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2019] [Revised: 02/06/2020] [Accepted: 02/08/2020] [Indexed: 12/19/2022]
|
18
|
Accogli A, St-Onge J, Addour-Boudrahem N, Lafond-Lapalme J, Laporte AD, Rouleau GA, Rivière JB, Srour M. Heterozygous Missense Pathogenic Variants Within the Second Spectrin Repeat of SPTBN2 Lead to Infantile-Onset Cerebellar Ataxia. J Child Neurol 2020; 35:106-110. [PMID: 31617442 DOI: 10.1177/0883073819878917] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
The term spinocerebellar ataxia encompasses a heterogeneous group of neurodegenerative disorders due to pathogenic variants in more than 100 genes, underlying 2 major groups of ataxia: autosomal dominant cerebellar ataxias (ADCA, also known as spinocerebellar ataxias [SCAs]) due to heterozygous variants or polyglutamine triplet expansions leading to adult-onset ataxia, and autosomal recessive spinocerebellar ataxias (ARCAs, also known as SCARs) due to biallelic variants, usually resulting in more severe and earlier-onset cerebellar ataxia. Certain ataxia genes, including SPTBN2 which encodes β-III spectrin, are responsible for both SCA and SCAR, depending on whether the pathogenic variant occurs in a monoallelic or biallelic state, respectively. Accordingly, 2 major phenotypes have been linked to SPTBN2: pathogenic heterozygous in-frame deletions and missense variants result in an adult-onset, slowly progressive ADCA (SCA5) through a dominant negative effect, whereas biallelic loss-of-function variants cause SCAR14, an allelic disorder characterized by infantile-onset cerebellar ataxia and cognitive impairment. Of note, 2 heterozygous missense variants (c.1438C>T, p.R480 W; c.1309C>G, p.R437G), both lying in the second spectrin repeat of SPTBN2, have been linked to infantile-onset cerebellar ataxia, similar to SCAR14. Here, we report a novel de novo heterozygous pathogenic missense variant (c.1310G>A) in SPTBN2 in a child with infantile-onset cerebellar ataxia and mild cognitive impairment. This variant affects the same R437 residue of the second spectrin repeat but results in a different amino acid change (p.R437Q). We review previously reported cases and discuss possible pathomechanisms responsible for the early-onset cerebellar phenotype due to disease-causing variants in the second spectrin repeat.
Collapse
Affiliation(s)
- Andrea Accogli
- Department of Pediatrics, Division of Pediatric Neurology, McGill University, Montreal, Quebec, Canada.,IRCCS Policlinico San Martino, Genova, Italy.,DINOGMI-Università degli Studi di Genova, Italy
| | - Judith St-Onge
- McGill University Health Center (MUHC) Research Institute, Montreal, Quebec, Canada
| | | | - Joël Lafond-Lapalme
- McGill University Health Center (MUHC) Research Institute, Montreal, Quebec, Canada
| | | | - Guy A Rouleau
- Montreal Neurological Institute, McGill University, Montreal, Quebec, Canada
| | | | - Myriam Srour
- Department of Pediatrics, Division of Pediatric Neurology, McGill University, Montreal, Quebec, Canada.,McGill University Health Center (MUHC) Research Institute, Montreal, Quebec, Canada
| |
Collapse
|
19
|
Al-Muhaizea MA, AlMutairi F, Almass R, AlHarthi S, Aldosary MS, Alsagob M, AlOdaib A, Colak D, Kaya N. A Novel Homozygous Mutation in SPTBN2 Leads to Spinocerebellar Ataxia in a Consanguineous Family: Report of a New Infantile-Onset Case and Brief Review of the Literature. THE CEREBELLUM 2019; 17:276-285. [PMID: 29196973 DOI: 10.1007/s12311-017-0893-2] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
The objective of this study was the identification of likely genes and mutations associated with an autosomal recessive (AR) rare spinocerebellar ataxia (SCA) phenotype in two patients with infantile onset, from a consanguineous family. Using genome-wide SNP screening, autozygosity mapping, targeted Sanger sequencing and nextgen sequencing, family segregation analysis, and comprehensive neuropanel, we discovered a novel mutation in SPTBN2. Next, we utilized multiple sequence alignment of amino acids from various species as well as crystal structures provided by protein data bank (PDB# 1WYQ and 1WJM) to model the mutation site and its effect on β-III-spectrin. Finally, we used various bioinformatic classifiers to determine pathogenicity of the missense variant. A comprehensive clinical and diagnostic workup including radiological exams were performed on the patients as part of routine patient care. The homozygous missense variant (c.1572C>T; p.R414C) detected in exon 2 was fully segregated in the family and absent in a large ethnic cohort as well as publicly available data sets. Our comprehensive targeted sequencing approaches did not reveal any other likely candidate variants or mutations in both patients. The two male siblings presented with delayed motor milestones and cognitive and learning disability. Brain MRI revealed isolated cerebellar atrophy more marked in midline inferior vermis at ages of 3 and 6.5 years. Sequence alignments of the amino acids for β-III-spectrin indicated that the arginine at 414 is highly conserved among various species and located towards the end of first spectrin repeat domain. Inclusive bioinformatic analysis predicted that the variant is to be damaging and disease causing. In addition to the novel mutation, a brief literature review of the previously reported mutations as well as clinical comparison of the cases were also presented. Our study reviews the previously reported SPTBN2 mutations and cases. Moreover, the novel mutation, p.R414C, adds up to the literature for the infantile-onset form of autosomal recessive ataxia associated with SPTBN2. Previously, few SPTBN2 recessive mutations have been reported in humans. Animal models especially the β-III-/- mouse model provided insights into early coordination and gait deficit suggestive of loss-of-function. It is expected to see more recessive SPTBN2 mutations appearing in the literature during the upcoming years.
Collapse
Affiliation(s)
- Mohammad A Al-Muhaizea
- Department of Neurosciences, King Faisal Specialist Hospital & Research Centre, Riyadh, Saudi Arabia.,College of Medicine, Al Faisal University, Riyadh, Saudi Arabia
| | - Faten AlMutairi
- Genetics Department, King Faisal Specialist Hospital and Research Center, MBC: 03, Riyadh, 11211, Saudi Arabia
| | - Rawan Almass
- Genetics Department, King Faisal Specialist Hospital and Research Center, MBC: 03, Riyadh, 11211, Saudi Arabia
| | - Safinaz AlHarthi
- Department of Neurosciences, King Faisal Specialist Hospital & Research Centre, Riyadh, Saudi Arabia
| | - Mazhor S Aldosary
- Genetics Department, King Faisal Specialist Hospital and Research Center, MBC: 03, Riyadh, 11211, Saudi Arabia
| | - Maysoon Alsagob
- Genetics Department, King Faisal Specialist Hospital and Research Center, MBC: 03, Riyadh, 11211, Saudi Arabia
| | - Ali AlOdaib
- Genetics Department, King Faisal Specialist Hospital and Research Center, MBC: 03, Riyadh, 11211, Saudi Arabia
| | - Dilek Colak
- Department of Biostatistics and Scientific Computing, King Faisal Specialist Hospital & Research Center, Riyadh, Saudi Arabia
| | - Namik Kaya
- Genetics Department, King Faisal Specialist Hospital and Research Center, MBC: 03, Riyadh, 11211, Saudi Arabia.
| |
Collapse
|
20
|
Corral-Juan M, Serrano-Munuera C, Rábano A, Cota-González D, Segarra-Roca A, Ispierto L, Cano-Orgaz AT, Adarmes AD, Méndez-Del-Barrio C, Jesús S, Mir P, Volpini V, Alvarez-Ramo R, Sánchez I, Matilla-Dueñas A. Clinical, genetic and neuropathological characterization of spinocerebellar ataxia type 37. Brain 2019; 141:1981-1997. [PMID: 29939198 DOI: 10.1093/brain/awy137] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2017] [Accepted: 04/03/2018] [Indexed: 12/20/2022] Open
Abstract
The autosomal dominant spinocerebellar ataxias (SCAs) consist of a highly heterogeneous group of rare movement disorders characterized by progressive cerebellar ataxia variably associated with ophthalmoplegia, pyramidal and extrapyramidal signs, dementia, pigmentary retinopathy, seizures, lower motor neuron signs, or peripheral neuropathy. Over 41 different SCA subtypes have been described evidencing the high clinical and genetic heterogeneity. We previously reported a novel spinocerebellar ataxia type subtype, SCA37, linked to an 11-Mb genomic region on 1p32, in a large Spanish ataxia pedigree characterized by ataxia and a pure cerebellar syndrome distinctively presenting with early-altered vertical eye movements. Here we demonstrate the segregation of an unstable intronic ATTTC pentanucleotide repeat mutation within the 1p32 5' non-coding regulatory region of the gene encoding the reelin adaptor protein DAB1, implicated in neuronal migration, as the causative genetic defect of the disease in four Spanish SCA37 families. We describe the clinical-genetic correlation and the first SCA37 neuropathological findings caused by dysregulation of cerebellar DAB1 expression. Post-mortem neuropathology of two patients with SCA37 revealed severe loss of Purkinje cells with abundant astrogliosis, empty baskets, occasional axonal spheroids, and hypertrophic fibres by phosphorylated neurofilament immunostaining in the cerebellar cortex. The remaining cerebellar Purkinje neurons showed loss of calbindin immunoreactivity, aberrant dendrite arborization, nuclear pathology including lobulation, irregularity, and hyperchromatism, and multiple ubiquitinated perisomatic granules immunostained for DAB1. A subpopulation of Purkinje cells was found ectopically mispositioned within the cerebellar cortex. No significant neuropathological alterations were identified in other brain regions in agreement with a pure cerebellar syndrome. Importantly, we found that the ATTTC repeat mutation dysregulated DAB1 expression and induced an RNA switch resulting in the upregulation of reelin-DAB1 and PI3K/AKT signalling in the SCA37 cerebellum. This study reveals the unstable ATTTC repeat mutation within the DAB1 gene as the underlying genetic cause and provides evidence of reelin-DAB1 signalling dysregulation in the spinocerebellar ataxia type 37.
Collapse
Affiliation(s)
- 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
| | | | | | - Daniel Cota-González
- 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
| | - Anna Segarra-Roca
- 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
| | - Lourdes Ispierto
- Neurodegeneration Unit, Neurology Service, Department of Neuroscience, University Hospital Germans Trias i Pujol (HUGTiP), Can Ruti Campus, Badalona, Barcelona, Spain
| | | | - Astrid D Adarmes
- Unidad de Trastornos del Movimiento, Servicio de Neurología, Instituto de Biomedicina de Sevilla (IBiS), Hospital Universitario Virgen del Rocío, CSIC, Universidad de Sevilla, Seville, Spain
| | - Carlota Méndez-Del-Barrio
- Unidad de Trastornos del Movimiento, Servicio de Neurología, Instituto de Biomedicina de Sevilla (IBiS), Hospital Universitario Virgen del Rocío, CSIC, Universidad de Sevilla, Seville, Spain
| | - Silvia Jesús
- Unidad de Trastornos del Movimiento, Servicio de Neurología, Instituto de Biomedicina de Sevilla (IBiS), Hospital Universitario Virgen del Rocío, CSIC, Universidad de Sevilla, Seville, Spain
| | - Pablo Mir
- Unidad de Trastornos del Movimiento, Servicio de Neurología, Instituto de Biomedicina de Sevilla (IBiS), Hospital Universitario Virgen del Rocío, CSIC, Universidad de Sevilla, Seville, Spain.,CIBERNED, Spain
| | | | - Ramiro Alvarez-Ramo
- Neurodegeneration Unit, Neurology Service, Department of Neuroscience, University Hospital Germans Trias i Pujol (HUGTiP), Can Ruti Campus, Badalona, Barcelona, Spain
| | - Ivelisse Sánchez
- 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
| |
Collapse
|
21
|
Nicita F, Nardella M, Bellacchio E, Alfieri P, Terrone G, Piccini G, Graziola F, Pignata C, Capuano A, Bertini E, Zanni G. Heterozygous missense variants of SPTBN2 are a frequent cause of congenital cerebellar ataxia. Clin Genet 2019; 96:169-175. [PMID: 31066025 DOI: 10.1111/cge.13562] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2019] [Revised: 05/02/2019] [Accepted: 05/04/2019] [Indexed: 11/30/2022]
Abstract
Heterozygous missense variants in the SPTBN2 gene, encoding the non-erythrocytic beta spectrin 2 subunit (beta-III spectrin), have been identified in autosomal dominant spinocerebellar ataxia type 5 (SCA5), a rare adult-onset neurodegenerative disorder characterized by progressive cerebellar ataxia, whereas homozygous loss of function variants in SPTBN2 have been associated with early onset cerebellar ataxia and global developmental delay (SCAR14). Recently, heterozygous SPTBN2 missense variants have been identified in a few patients with an early-onset ataxic phenotype. We report five patients with non-progressive congenital ataxia and psychomotor delay, 4/5 harboring novel heterozygous missense variants in SPTBN2 and one patient with compound heterozygous SPTBN2 variants. With an overall prevalence of 5% in our cohort of unrelated patients screened by targeted next-generation sequencing (NGS) for congenital or early-onset cerebellar ataxia, this study indicates that both dominant and recessive mutations of SPTBN2 together with CACNA1A and ITPR1, are a frequent cause of early-onset/congenital non-progressive ataxia and that their screening should be implemented in this subgroup of disorders.
Collapse
Affiliation(s)
- Francesco Nicita
- Unit of Muscular and Neurodegenerative Diseases, Department of Neurosciences, Bambino Gesù Children's Hospital, Rome, Italy
| | - Marta Nardella
- Unit of Muscular and Neurodegenerative Diseases, Department of Neurosciences, Bambino Gesù Children's Hospital, Rome, Italy
| | - Emanuele Bellacchio
- Genetics and Rare Diseases Research Division, Bambino Gesù Children's Hospital, Rome, Italy
| | - Paolo Alfieri
- Unit of Child Neuropsychiatry, Department of Neurosciences, Bambino Gesù Children's Hospital, Rome, Italy
| | - Gaetano Terrone
- Department of Translational Medical Sciences, Section of Pediatrics, University of Naples Federico II, Naples, Italy
| | - Giorgia Piccini
- Unit of Child Neuropsychiatry, Department of Neurosciences, Bambino Gesù Children's Hospital, Rome, Italy
| | - Federica Graziola
- Unit of Neurology, Department of Neurosciences, Bambino Gesù Children's Hospital, Rome, Italy
| | - Claudio Pignata
- Department of Translational Medical Sciences, Section of Pediatrics, University of Naples Federico II, Naples, Italy
| | - Alessandro Capuano
- Unit of Neurology, Department of Neurosciences, Bambino Gesù Children's Hospital, Rome, Italy
| | - Enrico Bertini
- Unit of Muscular and Neurodegenerative Diseases, Department of Neurosciences, Bambino Gesù Children's Hospital, Rome, Italy
| | - Ginevra Zanni
- Unit of Muscular and Neurodegenerative Diseases, Department of Neurosciences, Bambino Gesù Children's Hospital, Rome, Italy
| |
Collapse
|
22
|
Tarnutzer AA, Straumann D, Salman MS. Neuro-ophthalmologic assessment and investigations in children and adults with cerebellar diseases. THE CEREBELLUM: FROM EMBRYOLOGY TO DIAGNOSTIC INVESTIGATIONS 2018; 154:305-327. [DOI: 10.1016/b978-0-444-63956-1.00019-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
|
23
|
|
24
|
Structural basis for high-affinity actin binding revealed by a β-III-spectrin SCA5 missense mutation. Nat Commun 2017; 8:1350. [PMID: 29116080 PMCID: PMC5676748 DOI: 10.1038/s41467-017-01367-w] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2017] [Accepted: 09/08/2017] [Indexed: 12/24/2022] Open
Abstract
Spinocerebellar ataxia type 5 (SCA5) is a neurodegenerative disease caused by mutations in the cytoskeletal protein β-III-spectrin. Previously, a SCA5 mutation resulting in a leucine-to-proline substitution (L253P) in the actin-binding domain (ABD) was shown to cause a 1000-fold increase in actin-binding affinity. However, the structural basis for this increase is unknown. Here, we report a 6.9 Å cryo-EM structure of F-actin complexed with the L253P ABD. This structure, along with co-sedimentation and pulsed-EPR measurements, demonstrates that high-affinity binding caused by the CH2-localized mutation is due to opening of the two CH domains. This enables CH1 to bind actin aided by an unstructured N-terminal region that becomes α-helical upon binding. This helix is required for association with actin as truncation eliminates binding. Collectively, these results shed light on the mechanism by which β-III-spectrin, and likely similar actin-binding proteins, interact with actin, and how this mechanism can be perturbed to cause disease.
Collapse
|
25
|
Liu LZ, Ren M, Li M, Ren YT, Sun B, Sun XS, Chen SY, Li SY, Huang XS. A Novel Missense Mutation in the Spectrin Beta Nonerythrocytic 2 Gene Likely Associated with Spinocerebellar Ataxia Type 5. Chin Med J (Engl) 2017; 129:2516-2517. [PMID: 27748352 PMCID: PMC5072272 DOI: 10.4103/0366-6999.191834] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Affiliation(s)
- Li-Zhi Liu
- Department of Neurology, Chinese People's Liberation Army General Hospital, Beijing 100853, China
| | - Ming Ren
- Department of Neurology, Affiliated Hospital of Weifang Medical University, Weifang, Shandong 261031, China
| | - Mao Li
- Department of Neurology, Chinese People's Liberation Army General Hospital, Beijing 100853, China
| | - Yu-Ting Ren
- Department of Neurology, Chinese People's Liberation Army General Hospital, Beijing 100853, China
| | - Bo Sun
- Department of Neurology, Chinese People's Liberation Army General Hospital, Beijing 100853, China
| | - Xiao-Sun Sun
- Department of Neurology, Chinese People's Liberation Army General Hospital, Beijing 100853, China
| | - Si-Yu Chen
- Department of Neurology, Chinese People's Liberation Army General Hospital, Beijing 100853, China
| | - Si-Yuan Li
- Department of Neurology, Chinese People's Liberation Army General Hospital, Beijing 100853, China
| | - Xu-Sheng Huang
- Department of Neurology, Chinese People's Liberation Army General Hospital, Beijing 100853, China
| |
Collapse
|
26
|
Nibbeling EAR, Delnooz CCS, de Koning TJ, Sinke RJ, Jinnah HA, Tijssen MAJ, Verbeek DS. Using the shared genetics of dystonia and ataxia to unravel their pathogenesis. Neurosci Biobehav Rev 2017; 75:22-39. [PMID: 28143763 DOI: 10.1016/j.neubiorev.2017.01.033] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2016] [Revised: 12/09/2016] [Accepted: 01/24/2017] [Indexed: 12/13/2022]
Abstract
In this review we explore the similarities between spinocerebellar ataxias and dystonias, and suggest potentially shared molecular pathways using a gene co-expression network approach. The spinocerebellar ataxias are a group of neurodegenerative disorders characterized by coordination problems caused mainly by atrophy of the cerebellum. The dystonias are another group of neurological movement disorders linked to basal ganglia dysfunction, although evidence is now pointing to cerebellar involvement as well. Our gene co-expression network approach identified 99 shared genes and showed the involvement of two major pathways: synaptic transmission and neurodevelopment. These pathways overlapped in the two disorders, with a large role for GABAergic signaling in both. The overlapping pathways may provide novel targets for disease therapies. We need to prioritize variants obtained by whole exome sequencing in the genes associated with these pathways in the search for new pathogenic variants, which can than be used to help in the genetic counseling of patients and their families.
Collapse
Affiliation(s)
- Esther A R Nibbeling
- University of Groningen, University Medical Center Groningen, Department of Genetics, Groningen, The Netherlands
| | - Cathérine C S Delnooz
- University of Groningen, University Medical Center Groningen, Department of Neurology, Groningen, The Netherlands
| | - Tom J de Koning
- University of Groningen, University Medical Center Groningen, Department of Genetics, Groningen, The Netherlands; University of Groningen, University Medical Center Groningen, Department of Neurology, Groningen, The Netherlands
| | - Richard J Sinke
- University of Groningen, University Medical Center Groningen, Department of Genetics, Groningen, The Netherlands
| | - Hyder A Jinnah
- Departments of Neurology, Human Genetics and Pediatrics, Emory Clinic, Atlanta, USA
| | - Marina A J Tijssen
- University of Groningen, University Medical Center Groningen, Department of Neurology, Groningen, The Netherlands
| | - Dineke S Verbeek
- University of Groningen, University Medical Center Groningen, Department of Genetics, Groningen, The Netherlands.
| |
Collapse
|
27
|
Perkins E, Suminaite D, Jackson M. Cerebellar ataxias: β-III spectrin's interactions suggest common pathogenic pathways. J Physiol 2016; 594:4661-76. [PMID: 26821241 PMCID: PMC4983618 DOI: 10.1113/jp271195] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2015] [Accepted: 12/14/2015] [Indexed: 12/12/2022] Open
Abstract
Spinocerebellar ataxias (SCAs) are a genetically heterogeneous group of disorders all characterised by postural abnormalities, motor deficits and cerebellar degeneration. Animal and in vitro models have revealed β‐III spectrin, a cytoskeletal protein present throughout the soma and dendritic tree of cerebellar Purkinje cells, to be required for the maintenance of dendritic architecture and for the trafficking and/or stabilisation of several membrane proteins: ankyrin‐R, cell adhesion molecules, metabotropic glutamate receptor‐1 (mGluR1), voltage‐gated sodium channels (Nav) and glutamate transporters. This scaffold of interactions connects β‐III spectrin to a wide variety of proteins implicated in the pathology of many SCAs. Heterozygous mutations in the gene encoding β‐III spectrin (SPTBN2) underlie SCA type‐5 whereas homozygous mutations cause spectrin associated autosomal recessive ataxia type‐1 (SPARCA1), an infantile form of ataxia with cognitive impairment. Loss‐of β‐III spectrin function appears to underpin cerebellar dysfunction and degeneration in both diseases resulting in thinner dendrites, excessive dendritic protrusion with loss of planarity, reduced resurgent sodium currents and abnormal glutamatergic neurotransmission. The initial physiological consequences are a decrease in spontaneous activity and excessive excitation, likely to be offsetting each other, but eventually hyperexcitability gives rise to dark cell degeneration and reduced cerebellar output. Similar molecular mechanisms have been implicated for SCA1, 2, 3, 7, 13, 14, 19, 22, 27 and 28, highlighting alterations to intrinsic Purkinje cell activity, dendritic architecture and glutamatergic transmission as possible common mechanisms downstream of various loss‐of‐function primary genetic defects. A key question for future research is whether similar mechanisms underlie progressive cerebellar decline in normal ageing.
![]()
Collapse
Affiliation(s)
- Emma Perkins
- Centre for Integrative Physiology, University of Edinburgh, Hugh Robson Building, George Square, Edinburgh, EH8 9XD, UK
| | - Daumante Suminaite
- Centre for Integrative Physiology, University of Edinburgh, Hugh Robson Building, George Square, Edinburgh, EH8 9XD, UK
| | - Mandy Jackson
- Centre for Integrative Physiology, University of Edinburgh, Hugh Robson Building, George Square, Edinburgh, EH8 9XD, UK
| |
Collapse
|
28
|
Avery AW, Crain J, Thomas DD, Hays TS. A human β-III-spectrin spinocerebellar ataxia type 5 mutation causes high-affinity F-actin binding. Sci Rep 2016; 6:21375. [PMID: 26883385 PMCID: PMC4756369 DOI: 10.1038/srep21375] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2015] [Accepted: 01/21/2016] [Indexed: 01/06/2023] Open
Abstract
Spinocerebellar ataxia type 5 (SCA5) is a human neurodegenerative disease that stems from mutations in the SPTBN2 gene encoding the protein β-III-spectrin. Here we investigated the molecular consequence of a SCA5 missense mutation that results in a L253P substitution in the actin-binding domain (ABD) of β-III-spectrin. We report that the L253P substitution in the isolated β-III-spectrin ABD causes strikingly high F-actin binding affinity (Kd = 75.5 nM) compared to the weak F-actin binding affinity of the wild-type ABD (Kd = 75.8 μM). The mutation also causes decreased thermal stability (Tm = 44.6 °C vs 59.5 °C). Structural analyses indicate that leucine 253 is in a loop at the interface of the tandem calponin homology (CH) domains comprising the ABD. Leucine 253 is predicted to form hydrophobic contacts that bridge the CH domains. The decreased stability of the mutant indicates that these bridging interactions are probably disrupted, suggesting that the high F-actin binding affinity of the mutant is due to opening of the CH domain interface. These results support a fundamental role for leucine 253 in regulating opening of the CH domain interface and binding of the ABD to F-actin. This study indicates that high-affinity actin binding of L253P β-III-spectrin is a likely driver of neurodegeneration.
Collapse
Affiliation(s)
- Adam W Avery
- Department of Genetics, Cell Biology and Development, University of Minnesota, Minneapolis, MN 55455
| | - Jonathan Crain
- Department of Biochemistry, Molecular Biology, and Biophysics, University of Minnesota, Minneapolis, MN 55455
| | - David D Thomas
- Department of Biochemistry, Molecular Biology, and Biophysics, University of Minnesota, Minneapolis, MN 55455
| | - Thomas S Hays
- Department of Genetics, Cell Biology and Development, University of Minnesota, Minneapolis, MN 55455
| |
Collapse
|
29
|
Mutant β-III spectrin causes mGluR1α mislocalization and functional deficits in a mouse model of spinocerebellar ataxia type 5. J Neurosci 2014; 34:9891-904. [PMID: 25057192 DOI: 10.1523/jneurosci.0876-14.2014] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
Spinocerebellar ataxia type 5 (SCA5), a dominant neurodegenerative disease characterized by profound Purkinje cell loss, is caused by mutations in SPTBN2, a gene that encodes β-III spectrin. SCA5 is the first neurodegenerative disorder reported to be caused by mutations in a cytoskeletal spectrin gene. We have developed a mouse model to understand the mechanistic basis for this disease and show that expression of mutant but not wild-type β-III spectrin causes progressive motor deficits and cerebellar degeneration. We show that endogenous β-III spectrin interacts with the metabotropic glutamate receptor 1α (mGluR1α) and that mice expressing mutant β-III spectrin have cerebellar dysfunction with altered mGluR1α localization at Purkinje cell dendritic spines, decreased mGluR1-mediated responses, and deficient mGluR1-mediated long-term potentiation. These results indicate that mutant β-III spectrin causes mislocalization and dysfunction of mGluR1α at dendritic spines and connects SCA5 with other disorders involving glutamatergic dysfunction and synaptic plasticity abnormalities.
Collapse
|
30
|
Wang Y, Koh K, Miwa M, Yamashiro N, Shindo K, Takiyama Y. A Japanese SCA5 family with a novel three-nucleotide in-frame deletion mutation in the SPTBN2 gene: a clinical and genetic study. J Hum Genet 2014; 59:569-73. [PMID: 25142508 DOI: 10.1038/jhg.2014.74] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2014] [Revised: 07/23/2014] [Accepted: 07/28/2014] [Indexed: 11/09/2022]
Abstract
To date, four families with spinocerebellar ataxia type 5 (SCA5) with four distinct mutations in the spectrin, beta, nonerythrocytic 2 gene (SPTBN2) have been reported worldwide. In the present study, we identified the first Japanese family with SCA5, and analyzed this family clinically and genetically. The clinical features of the five patients in this family revealed late-onset autosomal-dominant pure cerebellar ataxia. We collected DNA samples from the majority of the family members across two generations, and exome sequencing combined with Sanger sequencing revealed a novel heterozygous three-nucleotide in-frame deletion mutation (c.2608_2610delGAG) in exon 14 of the SPTBN2 gene. This mutation cosegregated with the disease in the family and resulted in a glutamic acid deletion (p.E870del) in the sixth spectrin repeat, which is highly conserved in the SPTBN2 gene. This is the first three-nucleotide in-frame deletion mutation in this region of the beta-3 spectrin protein highly likely to be pathogenic based on exome and bioinformatic data.
Collapse
Affiliation(s)
- Ying Wang
- Department of Neurology, Interdisciplinary Graduate School of Medicine and Engineering, University of Yamanashi, Yamanashi, Japan
| | - Kishin Koh
- Department of Neurology, Interdisciplinary Graduate School of Medicine and Engineering, University of Yamanashi, Yamanashi, Japan
| | - Michiaki Miwa
- Department of Neurology, Interdisciplinary Graduate School of Medicine and Engineering, University of Yamanashi, Yamanashi, Japan
| | - Nobuo Yamashiro
- Department of Neurology, Interdisciplinary Graduate School of Medicine and Engineering, University of Yamanashi, Yamanashi, Japan
| | - Kazumasa Shindo
- Department of Neurology, Interdisciplinary Graduate School of Medicine and Engineering, University of Yamanashi, Yamanashi, Japan
| | - Yoshihisa Takiyama
- Department of Neurology, Interdisciplinary Graduate School of Medicine and Engineering, University of Yamanashi, Yamanashi, Japan
| |
Collapse
|
31
|
Abstract
Dominant spinocerebellar ataxias are a rare clinically and genetically heterogeneous group of neurodegenerative disorders. They are characterized by progressive cerebellar ataxia resulting in unsteady gait, clumsiness, dysarthria, and swallowing difficulty. The onset of symptoms is usually in the third or fourth decade of life; however, more subtle clinical manifestations can start in early childhood. Spinocerebellar ataxia type 5, a dominant spinocerebellar ataxia associated with mutations involving β-III spectrin (SPTBN2), has been described in 3 families. It typically consists of a slowly progressive spinocerebellar ataxia with onset in the third decade. The authors present the first case of infantile-onset spinocerebellar ataxia associated with a novel SPTBN2 mutation (transition C>T at nucleotide position 1438), the proband having a much more severe phenotype with global developmental delay, hypotonia, tremor, nystagmus, and facial myokymia.
Collapse
|
32
|
Fujioka S, Sundal C, Wszolek ZK. Autosomal dominant cerebellar ataxia type III: a review of the phenotypic and genotypic characteristics. Orphanet J Rare Dis 2013; 8:14. [PMID: 23331413 PMCID: PMC3558377 DOI: 10.1186/1750-1172-8-14] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2012] [Accepted: 01/16/2013] [Indexed: 12/26/2022] Open
Abstract
Autosomal Dominant Cerebellar Ataxia (ADCA) Type III is a type of spinocerebellar ataxia (SCA) classically characterized by pure cerebellar ataxia and occasionally by non-cerebellar signs such as pyramidal signs, ophthalmoplegia, and tremor. The onset of symptoms typically occurs in adulthood; however, a minority of patients develop clinical features in adolescence. The incidence of ADCA Type III is unknown. ADCA Type III consists of six subtypes, SCA5, SCA6, SCA11, SCA26, SCA30, and SCA31. The subtype SCA6 is the most common. These subtypes are associated with four causative genes and two loci. The severity of symptoms and age of onset can vary between each SCA subtype and even between families with the same subtype. SCA5 and SCA11 are caused by specific gene mutations such as missense, inframe deletions, and frameshift insertions or deletions. SCA6 is caused by trinucleotide CAG repeat expansions encoding large uninterrupted glutamine tracts. SCA31 is caused by repeat expansions that fall outside of the protein-coding region of the disease gene. Currently, there are no specific gene mutations associated with SCA26 or SCA30, though there is a confirmed locus for each subtype. This disease is mainly diagnosed via genetic testing; however, differential diagnoses include pure cerebellar ataxia and non-cerebellar features in addition to ataxia. Although not fatal, ADCA Type III may cause dysphagia and falls, which reduce the quality of life of the patients and may in turn shorten the lifespan. The therapy for ADCA Type III is supportive and includes occupational and speech modalities. There is no cure for ADCA Type III, but a number of recent studies have highlighted novel therapies, which bring hope for future curative treatments.
Collapse
Affiliation(s)
- Shinsuke Fujioka
- Department of Neurology at Mayo Clinic, 4500 San Pablo Road Cannaday Bldg 2-E, Jacksonville, FL 32224, USA
| | | | | |
Collapse
|
33
|
Lise S, Clarkson Y, Perkins E, Kwasniewska A, Sadighi Akha E, Parolin Schnekenberg R, Suminaite D, Hope J, Baker I, Gregory L, Green A, Allan C, Lamble S, Jayawant S, Quaghebeur G, Cader MZ, Hughes S, Armstrong RJE, Kanapin A, Rimmer A, Lunter G, Mathieson I, Cazier JB, Buck D, Taylor JC, Bentley D, McVean G, Donnelly P, Knight SJL, Jackson M, Ragoussis J, Németh AH. Recessive mutations in SPTBN2 implicate β-III spectrin in both cognitive and motor development. PLoS Genet 2012; 8:e1003074. [PMID: 23236289 PMCID: PMC3516553 DOI: 10.1371/journal.pgen.1003074] [Citation(s) in RCA: 82] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2012] [Accepted: 09/21/2012] [Indexed: 11/19/2022] Open
Abstract
β-III spectrin is present in the brain and is known to be important in the function of the cerebellum. Heterozygous mutations in SPTBN2, the gene encoding β-III spectrin, cause Spinocerebellar Ataxia Type 5 (SCA5), an adult-onset, slowly progressive, autosomal-dominant pure cerebellar ataxia. SCA5 is sometimes known as "Lincoln ataxia," because the largest known family is descended from relatives of the United States President Abraham Lincoln. Using targeted capture and next-generation sequencing, we identified a homozygous stop codon in SPTBN2 in a consanguineous family in which childhood developmental ataxia co-segregates with cognitive impairment. The cognitive impairment could result from mutations in a second gene, but further analysis using whole-genome sequencing combined with SNP array analysis did not reveal any evidence of other mutations. We also examined a mouse knockout of β-III spectrin in which ataxia and progressive degeneration of cerebellar Purkinje cells has been previously reported and found morphological abnormalities in neurons from prefrontal cortex and deficits in object recognition tasks, consistent with the human cognitive phenotype. These data provide the first evidence that β-III spectrin plays an important role in cortical brain development and cognition, in addition to its function in the cerebellum; and we conclude that cognitive impairment is an integral part of this novel recessive ataxic syndrome, Spectrin-associated Autosomal Recessive Cerebellar Ataxia type 1 (SPARCA1). In addition, the identification of SPARCA1 and normal heterozygous carriers of the stop codon in SPTBN2 provides insights into the mechanism of molecular dominance in SCA5 and demonstrates that the cell-specific repertoire of spectrin subunits underlies a novel group of disorders, the neuronal spectrinopathies, which includes SCA5, SPARCA1, and a form of West syndrome.
Collapse
Affiliation(s)
- Stefano Lise
- Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, United Kingdom
- NIHR Biomedical Research Centre Oxford, Oxford, United Kingdom
| | - Yvonne Clarkson
- Centre for Integrative Physiology, Euan MacDonald Centre for Motor Neurone Disease Research, University of Edinburgh, Edinburgh, United Kingdom
| | - Emma Perkins
- Centre for Integrative Physiology, Euan MacDonald Centre for Motor Neurone Disease Research, University of Edinburgh, Edinburgh, United Kingdom
| | - Alexandra Kwasniewska
- Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, United Kingdom
- Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, United Kingdom
| | - Elham Sadighi Akha
- Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, United Kingdom
- NIHR Biomedical Research Centre Oxford, Oxford, United Kingdom
| | - Ricardo Parolin Schnekenberg
- Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, United Kingdom
- School of Medicine, Universidade Positivo, Curitiba, Brazil
| | - Daumante Suminaite
- Centre for Integrative Physiology, Euan MacDonald Centre for Motor Neurone Disease Research, University of Edinburgh, Edinburgh, United Kingdom
| | - Jilly Hope
- Centre for Integrative Physiology, Euan MacDonald Centre for Motor Neurone Disease Research, University of Edinburgh, Edinburgh, United Kingdom
| | - Ian Baker
- Russell Cairns Unit, Oxford University Hospitals NHS Trust, Oxford, United Kingdom
| | - Lorna Gregory
- Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, United Kingdom
| | - Angie Green
- Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, United Kingdom
| | - Chris Allan
- Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, United Kingdom
| | - Sarah Lamble
- Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, United Kingdom
| | - Sandeep Jayawant
- Department of Paediatrics, Oxford University Hospitals NHS Trust, Oxford, United Kingdom
| | - Gerardine Quaghebeur
- Department of Neuroradiology, Oxford University Hospitals NHS Trust, Oxford, United Kingdom
| | - M. Zameel Cader
- Department of Anatomy, Physiology, and Genetics, University of Oxford, Oxford, United Kingdom
| | - Sarah Hughes
- Royal Berkshire Foundation Trust Hospital, Reading, United Kingdom
| | - Richard J. E. Armstrong
- Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, United Kingdom
- Royal Berkshire Foundation Trust Hospital, Reading, United Kingdom
| | - Alexander Kanapin
- Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, United Kingdom
| | - Andrew Rimmer
- Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, United Kingdom
| | - Gerton Lunter
- Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, United Kingdom
| | - Iain Mathieson
- Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, United Kingdom
| | - Jean-Baptiste Cazier
- Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, United Kingdom
| | - David Buck
- Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, United Kingdom
| | - Jenny C. Taylor
- Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, United Kingdom
- NIHR Biomedical Research Centre Oxford, Oxford, United Kingdom
| | | | - Gilean McVean
- Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, United Kingdom
| | - Peter Donnelly
- Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, United Kingdom
| | - Samantha J. L. Knight
- Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, United Kingdom
- NIHR Biomedical Research Centre Oxford, Oxford, United Kingdom
| | - Mandy Jackson
- Centre for Integrative Physiology, Euan MacDonald Centre for Motor Neurone Disease Research, University of Edinburgh, Edinburgh, United Kingdom
| | - Jiannis Ragoussis
- Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, United Kingdom
| | - Andrea H. Németh
- Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, United Kingdom
- NIHR Biomedical Research Centre Oxford, Oxford, United Kingdom
- Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, United Kingdom
- Department of Clinical Genetics, Oxford University Hospitals NHS Trust, Oxford, United Kingdom
| |
Collapse
|
34
|
Floor K, Barøy T, Misceo D, Kanavin OJ, Fannemel M, Frengen E. A 1 Mb de novo deletion within 11q13.1q13.2 in a boy with mild intellectual disability and minor dysmorphic features. Eur J Med Genet 2012; 55:695-9. [PMID: 22986108 DOI: 10.1016/j.ejmg.2012.08.002] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2011] [Accepted: 08/03/2012] [Indexed: 11/30/2022]
Abstract
We report a 11 year old male patient ascertained for mild intellectual disability and minor dysmorphic features, carrying a 1 Mb de novo deletion on chromosome 11q13.1q13.2 detected by aCGH. This is the first report of a deletion in this region in a patient presenting with intellectual impairment and mild dysmorphic traits. The 1 Mb deleted area encompasses 47 RefSeq genes, including Cornichon homologue 2 (CNIH2), Cofilin-1 (CFL1) and neuronal PAS domain-containing protein 4 (NPAS4), which are highly expressed in the central nervous system. Knockout of the CNIH2 and CFL1 orthologues in animals results in migration disturbances, while low or no expression of Npas4 in mice results in impairment of memory and learning. These three genes have previously been suggested as candidate genes for neurological disorders.
Collapse
Affiliation(s)
- Karijn Floor
- Department of Medical Genetics, Institute of Clinical Medicine, University of Oslo, Norway.
| | | | | | | | | | | |
Collapse
|
35
|
Seidel K, Siswanto S, Brunt ERP, den Dunnen W, Korf HW, Rüb U. Brain pathology of spinocerebellar ataxias. Acta Neuropathol 2012; 124:1-21. [PMID: 22684686 DOI: 10.1007/s00401-012-1000-x] [Citation(s) in RCA: 278] [Impact Index Per Article: 23.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2012] [Revised: 05/25/2012] [Accepted: 05/25/2012] [Indexed: 12/22/2022]
Abstract
The autosomal dominant cerebellar ataxias (ADCAs) represent a heterogeneous group of neurodegenerative diseases with progressive ataxia and cerebellar degeneration. The current classification of this disease group is based on the underlying genetic defects and their typical disease courses. According to this categorization, ADCAs are divided into the spinocerebellar ataxias (SCAs) with a progressive disease course, and the episodic ataxias (EA) with episodic occurrences of ataxia. The prominent disease symptoms of the currently known and genetically defined 31 SCA types result from damage to the cerebellum and interconnected brain grays and are often accompanied by more specific extra-cerebellar symptoms. In the present review, we report the genetic and clinical background of the known SCAs and present the state of neuropathological investigations of brain tissue from SCA patients in the final disease stages. Recent findings show that the brain is commonly seriously affected in the polyglutamine SCAs (i.e. SCA1, SCA2, SCA3, SCA6, SCA7, and SCA17) and that the patterns of brain damage in these diseases overlap considerably in patients suffering from advanced disease stages. In the more rarely occurring non-polyglutamine SCAs, post-mortem neuropathological data currently are scanty and investigations have been primarily performed in vivo by means of MRI brain imaging. Only a minority of SCAs exhibit symptoms and degenerative patterns allowing for a clear and unambiguous diagnosis of the disease, e.g. retinal degeneration in SCA7, tau aggregation in SCA11, dentate calcification in SCA20, protein depositions in the Purkinje cell layer in SCA31, azoospermia in SCA32, and neurocutaneous phenotype in SCA34. The disease proteins of polyglutamine ataxias and some non-polyglutamine ataxias aggregate as cytoplasmic or intranuclear inclusions and serve as morphological markers. Although inclusions may impair axonal transport, bind transcription factors, and block protein quality control, detailed molecular and pathogenetic consequences remain to be determined.
Collapse
Affiliation(s)
- Kay Seidel
- Dr. Senckenbergisches Chronomedizinisches Institut, Goethe University, Theodor-Stern-Kai 7, 60950, Frankfurt/Main, Germany
| | | | | | | | | | | |
Collapse
|
36
|
Parker JL, Santiago M. Oculomotor aspects of the hereditary cerebellar ataxias. HANDBOOK OF CLINICAL NEUROLOGY 2012; 103:63-83. [PMID: 21827881 DOI: 10.1016/b978-0-444-51892-7.00003-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Affiliation(s)
- J Larry Parker
- Department of Neurology, University of Mississippi Medical Center, Jackson, MS 39216-4505, USA.
| | | |
Collapse
|
37
|
Dick KA, Ikeda Y, Day JW, Ranum LPW. Spinocerebellar ataxia type 5. HANDBOOK OF CLINICAL NEUROLOGY 2012; 103:451-9. [PMID: 21827906 DOI: 10.1016/b978-0-444-51892-7.00028-0] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
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.
Collapse
Affiliation(s)
- Katherine A Dick
- Department of Genetics, Cell Biology, and Development, University of Minnesota, Minneapolis, MN, USA
| | | | | | | |
Collapse
|
38
|
Sequeiros J, Martins S, Silveira I. Epidemiology and population genetics of degenerative ataxias. HANDBOOK OF CLINICAL NEUROLOGY 2012; 103:227-51. [PMID: 21827892 DOI: 10.1016/b978-0-444-51892-7.00014-0] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Affiliation(s)
- Jorge Sequeiros
- Institute of Molecular and Cell Biology, University of Porto, Portugal.
| | | | | |
Collapse
|
39
|
Whaley NR, Fujioka S, Wszolek ZK. Autosomal dominant cerebellar ataxia type I: a review of the phenotypic and genotypic characteristics. Orphanet J Rare Dis 2011; 6:33. [PMID: 21619691 PMCID: PMC3123548 DOI: 10.1186/1750-1172-6-33] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2009] [Accepted: 05/28/2011] [Indexed: 12/26/2022] Open
Abstract
Type I autosomal dominant cerebellar ataxia (ADCA) is a type of spinocerebellar ataxia (SCA) characterized by ataxia with other neurological signs, including oculomotor disturbances, cognitive deficits, pyramidal and extrapyramidal dysfunction, bulbar, spinal and peripheral nervous system involvement. The global prevalence of this disease is not known. The most common type I ADCA is SCA3 followed by SCA2, SCA1, and SCA8, in descending order. Founder effects no doubt contribute to the variable prevalence between populations. Onset is usually in adulthood but cases of presentation in childhood have been reported. Clinical features vary depending on the SCA subtype but by definition include ataxia associated with other neurological manifestations. The clinical spectrum ranges from pure cerebellar signs to constellations including spinal cord and peripheral nerve disease, cognitive impairment, cerebellar or supranuclear ophthalmologic signs, psychiatric problems, and seizures. Cerebellar ataxia can affect virtually any body part causing movement abnormalities. Gait, truncal, and limb ataxia are often the most obvious cerebellar findings though nystagmus, saccadic abnormalities, and dysarthria are usually associated. To date, 21 subtypes have been identified: SCA1-SCA4, SCA8, SCA10, SCA12-SCA14, SCA15/16, SCA17-SCA23, SCA25, SCA27, SCA28 and dentatorubral pallidoluysian atrophy (DRPLA). Type I ADCA can be further divided based on the proposed pathogenetic mechanism into 3 subclasses: subclass 1 includes type I ADCA caused by CAG repeat expansions such as SCA1-SCA3, SCA17, and DRPLA, subclass 2 includes trinucleotide repeat expansions that fall outside of the protein-coding regions of the disease gene including SCA8, SCA10 and SCA12. Subclass 3 contains disorders caused by specific gene deletions, missense mutation, and nonsense mutation and includes SCA13, SCA14, SCA15/16, SCA27 and SCA28. Diagnosis is based on clinical history, physical examination, genetic molecular testing, and exclusion of other diseases. Differential diagnosis is broad and includes secondary ataxias caused by drug or toxic effects, nutritional deficiencies, endocrinopathies, infections and post-infection states, structural abnormalities, paraneoplastic conditions and certain neurodegenerative disorders. Given the autosomal dominant pattern of inheritance, genetic counseling is essential and best performed in specialized genetic clinics. There are currently no known effective treatments to modify disease progression. Care is therefore supportive. Occupational and physical therapy for gait dysfunction and speech therapy for dysarthria is essential. Prognosis is variable depending on the type of ADCA and even among kindreds.
Collapse
|
40
|
Marelli C, Cazeneuve C, Brice A, Stevanin G, Dürr A. Autosomal dominant cerebellar ataxias. Rev Neurol (Paris) 2011; 167:385-400. [PMID: 21546047 DOI: 10.1016/j.neurol.2011.01.015] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2010] [Accepted: 01/27/2011] [Indexed: 12/30/2022]
Abstract
Cerebellar ataxias with autosomal dominant transmission (ADCA) are far rarer than sporadic cases of cerebellar ataxia. The identification of genes involved in dominant forms has confirmed the genetic heterogeneity of these conditions and of the underlying mechanisms and pathways. To date, at least 28 genetic loci and, among them, 20 genes have been identified. In many instances, the phenotype is not restricted to cerebellar dysfunction but includes more complex multisystemic neurological deficits. Seven ADCA (SCA1, 2, 3, 6, 7, 17, and dentatorubro-pallido-luysian atrophy) are caused by repeat expansions in the corresponding proteins; phenotype-genotype correlations have shown that repeat size influences the progression of the disease, its severity and clinical differences among patients, including the phenomenon of anticipation between generations. All other ADCA are caused either by non-coding repeat expansions, conventional mutations or large rearrangements in genes with different functions. This review will focus on the genetic features of ADCA and on the clinical differences among the different forms.
Collapse
Affiliation(s)
- C Marelli
- Département de génétique et cytogénétique, consultation de génétique clinique, CHU Pitié-Salpêtrière, AP-HP, 47, boulevard de l'Hôpital, 75013 Paris, France
| | | | | | | | | |
Collapse
|
41
|
Clarkson YL, Gillespie T, Perkins EM, Lyndon AR, Jackson M. Beta-III spectrin mutation L253P associated with spinocerebellar ataxia type 5 interferes with binding to Arp1 and protein trafficking from the Golgi. Hum Mol Genet 2010; 19:3634-41. [PMID: 20603325 DOI: 10.1093/hmg/ddq279] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
Spinocerebellar ataxia type 5 (SCA5) is an autosomal dominant neurodegenerative disorder caused by mutations in beta-III spectrin. A mouse lacking full-length beta-III spectrin has a phenotype closely mirroring symptoms of SCA5 patients. Here we report the analysis of heterozygous animals, which show no signs of ataxia or cerebellar degeneration up to 2 years of age. This argues against haploinsufficiency as a disease mechanism and points towards human mutations having a dominant-negative effect on wild-type (WT) beta-III spectrin function. Cell culture studies using beta-III spectrin with a mutation associated with SCA5 (L253P) reveal that mutant protein, instead of being found at the cell membrane, appears trapped in the cytoplasm associated with the Golgi apparatus. Furthermore, L253P beta-III spectrin prevents correct localization of WT beta-III spectrin and prevents EAAT4, a protein known to interact with beta-III spectrin, from reaching the plasma membrane. Interaction of beta-III spectrin with Arp1, a subunit of the dynactin-dynein complex, is also lost with the L253P substitution. Despite intracellular accumulation of proteins, this cellular stress does not induce the unfolded protein response, implying the importance of membrane protein loss in disease pathogenesis. Incubation at lower temperature (25 degrees C) rescues L253P beta-III spectrin interaction with Arp1 and normal protein trafficking to the membrane. These data provide evidence for a dominant-negative effect of an SCA5 mutation and show for the first time that trafficking of both beta-III spectrin and EAAT4 from the Golgi is disrupted through failure of the L253P mutation to interact with Arp1.
Collapse
Affiliation(s)
- Yvonne L Clarkson
- The Centre for Integrative Physiology, The University of Edinburgh, Edinburgh, UK
| | | | | | | | | |
Collapse
|
42
|
Loss of beta-III spectrin leads to Purkinje cell dysfunction recapitulating the behavior and neuropathology of spinocerebellar ataxia type 5 in humans. J Neurosci 2010; 30:4857-67. [PMID: 20371805 DOI: 10.1523/jneurosci.6065-09.2010] [Citation(s) in RCA: 101] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Mutations in SPTBN2, the gene encoding beta-III spectrin, cause spinocerebellar ataxia type 5 in humans (SCA5), a neurodegenerative disorder resulting in loss of motor coordination. How these mutations give rise to progressive ataxia and what the precise role beta-III spectrin plays in normal cerebellar physiology are unknown. We developed a mouse lacking full-length beta-III spectrin and found that homozygous mice reproduced features of SCA5 including gait abnormalities, tremor, deteriorating motor coordination, Purkinje cell loss, and cerebellar atrophy (molecular layer thinning). In vivo analysis reveals an age-related reduction in simple spike firing rate in surviving beta-III(-/-) Purkinje cells, whereas in vitro studies show these neurons to have reduced spontaneous firing, smaller sodium currents, and dysregulation of glutamatergic neurotransmission. Our data suggest an early loss of EAAT4- (protein interactor of beta-III spectrin) and a subsequent loss of GLAST-mediated uptake may play a role in neuronal pathology. These findings implicate a loss of beta-III spectrin function in SCA5 pathogenesis and indicate that there are at least two physiological effects of beta-III spectrin loss that underpin a progressive loss of inhibitory cerebellar output, namely an intrinsic Purkinje cell membrane defect due to reduced sodium currents and alterations in glutamate signaling.
Collapse
|
43
|
Abstract
Magnetic resonance (MR) imaging is widely used to visualize atrophic processes that occur during the pathogenesis of spinocerebellar ataxias (SCAs). T1-weighted images are utilized to rate the atrophy of cerebellar vermis, cerebellar hemispheres, pons and midbrain. Signal changes in the basal ganglia and ponto-cerebellar fibers are evaluated by T2-weighted and proton density-weighted images. However, two-dimensional (2D) images do not allow a reliable quantification of the degree of atrophy. The latter is now possible through the application of three-dimensional (3D) true volumetric methods, which should be used for research purposes. Ideally, these methods should allow automated segmentation of contrast-defined boundaries by using region growing algorithms, which can be applied successfully in structures of the posterior fossa and basal ganglia. Thin slice thickness helps to minimize partial volume effects. Whereas volumetric approaches rely on predetermined anatomical boundaries, voxel-based morphometry has been developed to determine group differences between different types of SCA (cross-sectional studies) or within one SCA entity (longitudinal studies). We will review recent results and how these methods are currently used to (i) separate sporadic and dominantly inherited forms of cerebellar ataxias; (ii) identify specific SCA genotypes; (iii) correlate patho-anatomical changes with SCA disease symptoms or severity; and (iv) visualize and estimate the rate of progression in SCA.
Collapse
|
44
|
Screening of the SPTBN2 (SCA5) gene in German SCA patients. J Neurol 2007; 254:1649-52. [DOI: 10.1007/s00415-007-0600-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2007] [Revised: 03/16/2007] [Accepted: 03/21/2007] [Indexed: 10/22/2022]
|
45
|
Dupré N, Gros-Louis F, Chrestian N, Verreault S, Brunet D, de Verteuil D, Brais B, Bouchard JP, Rouleau GA. Clinical and genetic study of autosomal recessive cerebellar ataxia type 1. Ann Neurol 2007; 62:93-8. [PMID: 17503513 DOI: 10.1002/ana.21143] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
OBJECTIVE Define the phenotype and genotype of a cluster of families with a relatively pure cerebellar ataxia referred to as autosomal recessive cerebellar ataxia type 1 (ARCA-1). METHODS We ascertained 64 probands and affected members of 30 French-Canadian families all showing similar clinical features and originating from the same region of Quebec. After informed consent, we performed detailed clinical history, neurological examination, brain imaging, nerve conduction studies, and SYNE1 mutation detection of all available subjects. RESULTS Based on the cases examined, ARCA-1 is a cerebellar syndrome characterized by recessive transmission, middle-age onset (mean, 31.60; range, 17-46 years), slow progression and moderate disability, significant dysarthria, mild oculomotor abnormalities, occasional brisk reflexes in the lower extremities, normal nerve conduction studies, and diffuse cerebellar atrophy on imaging. We identified a total of seven mutations in our population, thereby providing evidence of genotypic heterogeneity. Patients with different mutations did not show significant phenotypic heterogeneity. INTERPRETATION We identified a cluster of French-Canadian families with a new recessive ataxia of relatively pure cerebellar type caused by mutations in SYNE1. The function of SYNE1 is thus critical in the maintenance of cerebellar structure in humans. We expect that this disease will be a common cause of middle-age-onset recessive ataxia worldwide.
Collapse
Affiliation(s)
- Nicolas Dupré
- Faculty of Medicine, Laval University, Department of Neurological Sciences, Centre Hospitalier Affilié Universitaire de Québec-Enfant-Jésus, 18th Street, Quebec City, Québec, Canada.
| | | | | | | | | | | | | | | | | |
Collapse
|
46
|
Basri R, Yabe I, Soma H, Sasaki H. Spectrum and prevalence of autosomal dominant spinocerebellar ataxia in Hokkaido, the northern island of Japan: a study of 113 Japanese families. J Hum Genet 2007; 52:848-855. [PMID: 17805477 DOI: 10.1007/s10038-007-0182-x] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2007] [Accepted: 07/31/2007] [Indexed: 11/28/2022]
Abstract
Autosomal dominant cerebellar ataxia (ADCA) is a genetically heterogeneous group of neurodegenerative disorders. To shed further light on the clinical and genetic spectrum of ADCA in Japan, we conducted a study to determine the frequency of a new variety of different subtypes of SCAs among ADCA patients. This current study was carried out from April 1999 to December 2006 on the basis of patients with symptoms and signs of ADCA disorders. PCR and/or direct sequencing were evaluated in a total of 113 families. Among them, 35 families were found to have the mutation associated with SCA6, 30 with SCA3, 11 with SCA1, five with SCA2, five with DRPLA, and one with SCA14. We also detected the heterozygous -16C --> T single nucleotide substitution within the puratrophin-1 gene responsible for 16q22.1-linked ADCA in ten families. In this study, unusual varieties of SCA, including 27, 13, 5, 7, 8, 12, 17, and 16 were not found. Of the 113 patients, 14% had as yet unidentified ADCA mutations. The present study validates the prevalence of genetically distinct ADCA subtypes based on ethnic origin and geographical variation, and shows that 16q-linked ADCA has strong hereditary effects in patients with ADCAs in Japan.
Collapse
Affiliation(s)
- Rehana Basri
- Department of Neurology, Graduate School of Medicine, Hokkaido University, N15W7. Kita-Ku, Sapporo, 060-8368, Japan
| | - Ichiro Yabe
- Department of Neurology, Graduate School of Medicine, Hokkaido University, N15W7. Kita-Ku, Sapporo, 060-8368, Japan.
| | - Hiroyuki Soma
- Department of Neurology, Graduate School of Medicine, Hokkaido University, N15W7. Kita-Ku, Sapporo, 060-8368, Japan
| | - Hidenao Sasaki
- Department of Neurology, Graduate School of Medicine, Hokkaido University, N15W7. Kita-Ku, Sapporo, 060-8368, Japan
| |
Collapse
|
47
|
Zühlke C, Bürk K. Spinocerebellar ataxia type 17 is caused by mutations in the TATA-box binding protein. CEREBELLUM (LONDON, ENGLAND) 2007; 6:300-7. [PMID: 17853080 DOI: 10.1080/14734220601136177] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
The spinocerebellar ataxia type 17 (SCA17) is characterized by cerebellar ataxia, dementia, and involuntary movements, including chorea and dystonia. In addition, psychiatric symptoms, pyramidal signs, and rigidity are common. MRI shows variable atrophy of the cerebrum, brainstem, and cerebellum. The autosomal dominantly inherited progressive neurodegenerative disorder is caused by an expanded CAA/CAG repeat coding for glutamine. Alleles of the normal range carry 25 to 42 glutamine residues, disease causing alleles 43 to 63. Alleles with 43 to 48 glutamine codons may be associated with incomplete penetrance. The mean age of onset is about 30 years for individuals with full-penetrance alleles, but ranges from three to 55 years.
Collapse
Affiliation(s)
- Christine Zühlke
- Institute of Human Genetics, University of Lübeck, Lübeck, Germany.
| | | |
Collapse
|
48
|
Abstract
Recently, betaIII spectrins have been recognized as ataxia disease genes, with the identification by Ikeda and co-workers of pathogenic mutations in the SPTBN2 gene in three large (and mapped) SCA5 families of American and European origin.((1)) With their discovery, the large "Lincoln" family has been traced back to the underlying genetic defect for the slowly progressive cerebellar ataxia. In addition, the involvement of this component of the cytoskeleton directs attention towards the possible role of organelle stability during neurodegeneration. The findings suggest that the mechanical properties of neurons and their dynamics may be as important as altered Ca(2+) homeostasis, transcriptional dysregulation, and impaired protein degradation in neurodegeneration conditions.
Collapse
Affiliation(s)
- Peter Bauer
- Department of Medical Genetics, University of Tübingen, Germany
| | | | | |
Collapse
|
49
|
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: 268] [Impact Index Per Article: 14.9] [Reference Citation Analysis] [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.
Collapse
Affiliation(s)
- Yoshio Ikeda
- Department of Genetics, Cell Biology, and Development, University of Minnesota, 321 Church St. SE, Minneapolis, Minnesota 55455 USA
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
50
|
Zainabadi K, Benyamini P, Chakrabarti R, Veena MS, Chandrasekharappa SC, Gatti RA, Srivatsan ES. A 700-kb physical and transcription map of the cervical cancer tumor suppressor gene locus on chromosome 11q13. Genomics 2005; 85:704-14. [PMID: 15885497 DOI: 10.1016/j.ygeno.2005.02.014] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2004] [Revised: 02/11/2005] [Accepted: 02/25/2005] [Indexed: 11/18/2022]
Abstract
Nonrandom deletion of chromosome 11q13 sequences is a significant event in a number of human tumors. We have recently identified a 300-kb minimal area of deletion in primary cervical tumors that overlaps with deletions observed in endocrine and nasopharyngeal tumors. We have also observed a 5.7-kb homozygous deletion within this interval in HeLa cells (a cervical cancer cell line), HeLa cell-derived tumorigenic hybrids, and a primary cervical tumor, suggesting the presence of a tumor suppressor gene in this region. In the present investigation, we have constructed a 700-kb contig map encompassing the 300-kb deletion using the human genome sequence database and confirmed the map using various STS markers from the region. Our map also shows the overlap of a previously published rare, heritable fragile site, FRA11A, with the cervical cancer deletion locus. The mapped region contains highly repetitive GC-poor sequences. We have identified and characterized eight different polymorphic microsatellite markers from the sequences within and surrounding the deletion. Further, expression studies performed with 18 different ESTs localized adjacent to the homozygous deletion showed the presence of a transcript for only one of the ESTs, AA282789. This EST mapping within the homozygous deletion is also expressed in HeLa cells, thereby excluding the EST as the putative tumor suppressor gene. Additionally, analysis of four candidate genes (SF3B2, BRMS1, RIN1, and RAB1B) from the region showed expression of the expected size message in both the nontumorigenic and the tumorigenic HeLa cell hybrids, thereby excluding them as the putative tumor suppressor gene(s). However, Northern blot analysis with a fifth candidate gene, PACS1 (phosphofurin acidic cluster sorting protein), mapped to the deletion/FRA11A overlap region showed the expression of an 8-kb transcript in HeLa and five other tumor cell lines in addition to the expected 4.5-kb transcript. Since the gene shows abundant expression in normal tissues and an altered transcript is observed in tumor cell lines, we hypothesize that this gene could represent sequences of the putative tumor suppressor gene. Finally, we have observed a perfect 48-bp CAG/CCG repeat 99 kb proximal to D11S913, the marker linked to the neurodegenerative disorder spinocerebellar ataxia 5. The physical and transcription maps and the microsatellite markers of the 700-kb region of chromosome 11q13 should be helpful in the cloning of the cervical cancer tumor suppressor gene.
Collapse
Affiliation(s)
- Kayvan Zainabadi
- Department of Surgery 10H2, VAGLAHS West Los Angeles, David Geffen School of Medicine, University of California at Los Angeles, Building 304, Room E2-218, 11301 Wiltshire Boulevard, West Los Angeles, CA 90073, USA
| | | | | | | | | | | | | |
Collapse
|