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Aiken J, Holzbaur ELF. Spastin locally amplifies microtubule dynamics to pattern the axon for presynaptic cargo delivery. Curr Biol 2024; 34:1687-1704.e8. [PMID: 38554708 DOI: 10.1016/j.cub.2024.03.010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2023] [Revised: 01/10/2024] [Accepted: 03/08/2024] [Indexed: 04/02/2024]
Abstract
Neurons rely on the long-range trafficking of synaptic components to form and maintain the complex neural networks that encode the human experience. With a single neuron capable of forming thousands of distinct en passant synapses along its axon, spatially precise delivery of the necessary synaptic components is paramount. How these synapses are patterned, as well as how the efficient delivery of synaptic components is regulated, remains largely unknown. Here, we reveal a novel role for the microtubule (MT)-severing enzyme spastin in locally enhancing MT polymerization to influence presynaptic cargo pausing and retention along the axon. In human neurons derived from induced pluripotent stem cells (iPSCs), we identify sites stably enriched for presynaptic components along the axon prior to the robust assembly of mature presynapses apposed by postsynaptic contacts. These sites are capable of cycling synaptic vesicles, are enriched with spastin, and are hotspots for new MT growth and synaptic vesicle precursor (SVP) pausing/retention. The disruption of neuronal spastin level or activity, by CRISPRi-mediated depletion, transient overexpression, or pharmacologic inhibition of enzymatic activity, interrupts the localized enrichment of dynamic MT plus ends and diminishes SVP accumulation. Using an innovative human heterologous synapse model, where microfluidically isolated human axons recognize and form presynaptic connections with neuroligin-expressing non-neuronal cells, we reveal that neurons deficient for spastin do not achieve the same level of presynaptic component accumulation as control neurons. We propose a model where spastin acts locally as an amplifier of MT polymerization to pattern specific regions of the axon for synaptogenesis and guide synaptic cargo delivery.
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Affiliation(s)
- Jayne Aiken
- Department of Physiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Erika L F Holzbaur
- Department of Physiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA.
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Knight KAW, Barbour-Hastie C, Gane A, O'Riordan J. Novel genetic variant in hereditary spastic paraparesis. BMJ Case Rep 2024; 17:e252396. [PMID: 38631813 PMCID: PMC11029313 DOI: 10.1136/bcr-2022-252396] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/19/2024] Open
Abstract
A man in his 30s was referred to neurology with right-sided paraesthesia, tremors, chest pain and lower urinary tract and erectile dysfunction. He had a medical history of left acetabular dysplasia, and subjective memory impairment, the latter being in the context of depression and chronic pain with opioid use. There was no notable family history. On examination, he had a spastic paraparesis. Imaging revealed atrophy of the thoracic spine. Lumbar puncture demonstrated a raised protein but other constituents were normal, including no presence of oligoclonal bands. Genetic testing revealed a novel heterozygous likely pathogenic SPAST variant c. 1643A>T p.(Asp548Val), confirming the diagnosis of hereditary spastic paraparesis. Symptomatic treatment with physiotherapy and antispasmodic therapy was initiated. This is the first study reporting a patient with this SPAST variant. Ensembl variant effect predictor was used, with the application of computational variant prediction tools providing support that the variant we have identified is likely deleterious and damaging. Our variant CADD score was high, indicating that our identified variant was a highly deleterious substitution.
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Affiliation(s)
- Kathryn A W Knight
- Medical School, University of Dundee, Dundee, UK
- Department of Neurology, NHS Tayside, Dundee, UK
| | | | - Angus Gane
- The University of Edinburgh, Edinburgh, UK
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Jin Z, Zhang ZC, Xiao CY, Li MQ, Li QR, Gao LL. CRMP5 participates in oocyte meiosis by regulating spastin to correct microtubule-kinetochore misconnection. ZYGOTE 2024; 32:21-27. [PMID: 38047349 DOI: 10.1017/s0967199423000564] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/05/2023]
Abstract
Our previous studies have suggested that spastin, which aggregates on spindle microtubules in oocytes, may promote the assembly of mouse oocyte spindles by cutting microtubules. This action may be related to CRMP5, as knocking down CRMP5 results in reduced spindle microtubule density and maturation defects in oocytes. In this study, we found that, after knocking down CRMP5 in oocytes, spastin distribution shifted from the spindle to the spindle poles and errors in microtubule-kinetochore attachment appeared in oocyte spindles. However, CRMP5 did not interact with the other two microtubule-severing proteins, katanin-like-1 (KATNAL1) and fidgetin-like-1 (FIGNL1), which aggregate at the spindle poles. We speculate that, in oocytes, due to the reduction of spastin distribution on chromosomes after knocking down CRMP5, microtubule-kinetochore errors cannot be corrected through severing, resulting in meiotic division abnormalities and maturation defects in oocytes. This finding provides new insights into the regulatory mechanisms of spastin in oocytes and important opportunities for the study of meiotic division mechanisms.
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Affiliation(s)
- Zhen Jin
- Center for Reproductive Medicine, Department of Reproductive Endocrinology, Zhejiang Provincial People's Hospital (Affiliated People's Hospital), Hangzhou Medical College, Hangzhou, Zhejiang, 310014, China
| | - Zhi-Cai Zhang
- Department of Dispatching Management, Zibo Medical Emergency Command Center, Zibo, Shandong, 255030, China
| | - Chen-Yu Xiao
- Center for Reproductive Medicine, Department of Gynecology, Zhejiang Provincial People's Hospital (Affiliated People's Hospital), Hangzhou Medical College, Hangzhou, Zhejiang, 310014, China
| | - Mei-Qi Li
- Center for Reproductive Medicine, Department of Gynecology, Zhejiang Provincial People's Hospital (Affiliated People's Hospital), Hangzhou Medical College, Hangzhou, Zhejiang, 310014, China
| | - Qian-Ru Li
- Center for Reproductive Medicine, Department of Gynecology, Zhejiang Provincial People's Hospital (Affiliated People's Hospital), Hangzhou Medical College, Hangzhou, Zhejiang, 310014, China
| | - Lei-Lei Gao
- Center for Reproductive Medicine, Department of Gynecology, Zhejiang Provincial People's Hospital (Affiliated People's Hospital), Hangzhou Medical College, Hangzhou, Zhejiang, 310014, China
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Wang J, Liu Y, Zhang L, Zhao L, Liu X, Wang X. [Advance of research on Hereditary spastic paraplegia type 4]. Zhonghua Yi Xue Yi Chuan Xue Za Zhi 2024; 41:113-119. [PMID: 38171570 DOI: 10.3760/cma.j.cn511374-20221105-00762] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/05/2024]
Abstract
Spastic paraplegia type 4 (SPG4) is the most common type of autosomally inherited spastic paraplegia. Its main clinical features include typical simple hereditary spastic paraplegia, with neurological impairments limited to lower limb spasticity, hypertonic bladder dysfunction, and mild weakening of lower limb vibration sensation, without accompanying features such as nerve atrophy, ataxia, cognitive impairment, seizures, and muscle tone disorders. SPAST is the main pathogenic gene underlying SPG4, and various pathogenic SPAST variants have been discovered. This disease has featured a high degree of clinical heterogeneity, and the same pathogenic variant can have different age of onset and severity among different patients and even within the same family. There is a lack of systematic research on the correlation between the genotype and phenotype of SPG4, and the pathogenic mechanism has remained controversial. This article has provided a review for the clinical characteristics, pathogenic gene characteristics, correlation between the genotype and phenotype, and pathogenic mechanism of this disease, with an aim to provide reference for its clinical diagnosis and treatment.
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Affiliation(s)
- Jie Wang
- Department of Genetics, Inner Mongolia Maternity and Child Health Care Hospital, Hohhot, Inner Mongolia 010020, China.
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Aaltio J, Etula A, Ojanen S, Brilhante V, Lönnqvist T, Isohanni P, Suomalainen A. Genetic etiology of progressive pediatric neurological disorders. Pediatr Res 2024; 95:102-111. [PMID: 37563452 PMCID: PMC10798881 DOI: 10.1038/s41390-023-02767-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/13/2023] [Revised: 06/15/2023] [Accepted: 07/16/2023] [Indexed: 08/12/2023]
Abstract
BACKGROUND The aim of the study was to characterize molecular diagnoses in patients with childhood-onset progressive neurological disorders of suspected genetic etiology. METHODS We studied 48 probands (age range from newborn to 17 years old) with progressive neurological disorders of unknown etiology from the largest pediatric neurology clinic in Finland. Phenotypes included encephalopathy (54%), neuromuscular disorders (33%), movement disorders (11%), and one patient (2%) with hemiplegic migraine. All patients underwent whole-exome sequencing and disease-causing genes were analyzed. RESULTS We found 20 (42%) of the patients to have variants in genes previously associated with disease. Of these, 12 were previously reported disease-causing variants, whereas eight patients had a novel variant on a disease-causing gene: ATP7A, CHD2, PURA, PYCR2, SLC1A4, SPAST, TRIT1, and UPF3B. Genetics also enabled us to define atypical clinical presentations of Rett syndrome (MECP2) and Menkes disease (ATP7A). Except for one deletion, all findings were single-nucleotide variants (missense 72%, truncating 22%, splice-site 6%). Nearly half of the variants were de novo. CONCLUSIONS The most common cause of childhood encephalopathies are de novo variants. Whole-exome sequencing, even singleton, proved to be an efficient tool to gain specific diagnoses and in finding de novo variants in a clinically heterogeneous group of childhood encephalopathies. IMPACT Whole-exome sequencing is useful in heterogeneous pediatric neurology cohorts. Our article provides further evidence for and novel variants in several genes. De novo variants are an important cause of childhood encephalopathies.
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Affiliation(s)
- Juho Aaltio
- Research Programs Unit, Stem Cells and Metabolism, University of Helsinki, Helsinki, Finland.
| | - Anna Etula
- Research Programs Unit, Stem Cells and Metabolism, University of Helsinki, Helsinki, Finland
| | - Simo Ojanen
- Research Programs Unit, Stem Cells and Metabolism, University of Helsinki, Helsinki, Finland
- Department of Veterinary Biosciences, University of Helsinki, Helsinki, Finland
| | - Virginia Brilhante
- Research Programs Unit, Stem Cells and Metabolism, University of Helsinki, Helsinki, Finland
| | - Tuula Lönnqvist
- Department of Child Neurology, Children's Hospital, Pediatric Research Center, University of Helsinki and Helsinki University Hospital, Helsinki, Finland
| | - Pirjo Isohanni
- Research Programs Unit, Stem Cells and Metabolism, University of Helsinki, Helsinki, Finland
- Department of Child Neurology, Children's Hospital, Pediatric Research Center, University of Helsinki and Helsinki University Hospital, Helsinki, Finland
| | - Anu Suomalainen
- Research Programs Unit, Stem Cells and Metabolism, University of Helsinki, Helsinki, Finland.
- HUS Diagnostic Centre, Helsinki University Hospital, Helsinki, Finland.
- HiLife, University of Helsinki, Helsinki, Finland.
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Wang J, Wu Y, Dong H, Ji Y, Zhang L, Liu Y, Liu Y, Gao X, Jia Y, Wang X. A novel truncated variant in SPAST results in spastin accumulation and defects in microtubule dynamics. BMC Med Genomics 2023; 16:321. [PMID: 38066582 PMCID: PMC10704811 DOI: 10.1186/s12920-023-01759-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2023] [Accepted: 12/02/2023] [Indexed: 12/18/2023] Open
Abstract
OBJECTIVE Haploinsufficiency is widely accepted as the pathogenic mechanism of hereditary spastic paraplegias type 4 (SPG4). However, there are some cases that cannot be explained by reduced function of the spastin protein encoded by SPAST. The aim of this study was to identify the causative variant of SPG4 in a large Chinese family and explore its pathological mechanism. MATERIALS AND METHODS A five-generation family with 49 members including nine affected (4 males and 5 females) and 40 unaffected individuals in Mongolian nationality was recruited. Whole exome sequencing was employed to investigate the genetic etiology. Western blotting and immunofluorescence were used to analyze the effects of the mutant proteins in vitro. RESULTS A novel frameshift variant NM_014946.4: c.483_484delinsC (p.Val162Leufs*2) was identified in SPAST from a pedigree with SPG4. The variant segregated with the disease in the family and thus determined as the disease-causing variant. The c.483_484delinsC variant produced two truncated mutants (mutant M1 and M87 isoforms). They accumulated to a higher level and presented increased stability than their wild-type counterparts and may lost the microtubule severing activity. CONCLUSION SPAST mutations leading to premature stop codons do not always act through haploinsufficiency. The potential toxicity to the corticospinal tract caused by the intracellular accumulation of truncated spastin should be considered as the pathological mechanism of SPG4.
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Affiliation(s)
- Jie Wang
- Department of Genetics, Inner Mongolia Maternity and Child Health Care Hospital, Hohhot, 010020, China
- State Key Laboratory of Reproductive Regulation and Breeding of Grassland Livestock (RRBGL), Inner Mongolia University, Hohhot, 010070, China
| | - Yihan Wu
- Department of Family Medicine, Inner Mongolia People's Hospital, Hohhot, 010057, China
| | - Hong Dong
- Department of Genetics, Inner Mongolia Maternity and Child Health Care Hospital, Hohhot, 010020, China
| | - Yunpeng Ji
- Department of Genetics, Inner Mongolia Maternity and Child Health Care Hospital, Hohhot, 010020, China
| | - Lichun Zhang
- Department of Genetics, Inner Mongolia Maternity and Child Health Care Hospital, Hohhot, 010020, China
| | - Yaxian Liu
- Department of Genetics, Inner Mongolia Maternity and Child Health Care Hospital, Hohhot, 010020, China
| | - Yueshi Liu
- State Key Laboratory of Reproductive Regulation and Breeding of Grassland Livestock (RRBGL), Inner Mongolia University, Hohhot, 010070, China
| | - Xin Gao
- Department of Pediatrics, Inner Mongolia Maternity and Child Health Care Hospital, Hohhot, 010020, China
| | - Yueqi Jia
- Department of Genetics, Inner Mongolia Maternity and Child Health Care Hospital, Hohhot, 010020, China.
| | - Xiaohua Wang
- Department of Genetics, Inner Mongolia Maternity and Child Health Care Hospital, Hohhot, 010020, China.
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Fukuda H, Mizuguchi T, Doi H, Kameyama S, Kunii M, Joki H, Takahashi T, Komiya H, Sasaki M, Miyaji Y, Ohori S, Koshimizu E, Uchiyama Y, Tsuchida N, Fujita A, Hamanaka K, Misawa K, Miyatake S, Tanaka F, Matsumoto N. Long-read sequencing revealing intragenic deletions in exome-negative spastic paraplegias. J Hum Genet 2023; 68:689-697. [PMID: 37308565 DOI: 10.1038/s10038-023-01170-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2022] [Revised: 05/01/2023] [Accepted: 06/04/2023] [Indexed: 06/14/2023]
Abstract
Hereditary spastic paraplegias (HSPs) are a heterogeneous group of neurodegenerative disorders characterized by progressive spasticity and weakness in the lower extremities. To date, a total of 88 types of SPG are known. To diagnose HSP, multiple technologies, including microarray, direct sequencing, multiplex ligation-dependent probe amplification, and short-read next-generation sequencing, are often chosen based on the frequency of HSP subtypes. Exome sequencing (ES) is commonly used. We used ES to analyze ten cases of HSP from eight families. We identified pathogenic variants in three cases (from three different families); however, we were unable to determine the cause of the other seven cases using ES. We therefore applied long-read sequencing to the seven undetermined HSP cases (from five families). We detected intragenic deletions within the SPAST gene in four families, and a deletion within PSEN1 in the remaining family. The size of the deletion ranged from 4.7 to 12.5 kb and involved 1-7 exons. All deletions were entirely included in one long read. We retrospectively performed an ES-based copy number variation analysis focusing on pathogenic deletions, but were not able to accurately detect these deletions. This study demonstrated the efficiency of long-read sequencing in detecting intragenic pathogenic deletions in ES-negative HSP patients.
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Affiliation(s)
- Hiromi Fukuda
- Department of Human Genetics, Yokohama City University Graduate School of Medicine, Yokohama, 236-0004, Japan
- Department of Neurology and Stroke Medicine, Yokohama City University Graduate School of Medicine, Yokohama, 236-0004, Japan
| | - Takeshi Mizuguchi
- Department of Human Genetics, Yokohama City University Graduate School of Medicine, Yokohama, 236-0004, Japan.
| | - Hiroshi Doi
- Department of Neurology and Stroke Medicine, Yokohama City University Graduate School of Medicine, Yokohama, 236-0004, Japan
| | - Shinichi Kameyama
- Department of Human Genetics, Yokohama City University Graduate School of Medicine, Yokohama, 236-0004, Japan
- Department of Pathology, Keio University School of Medicine, Tokyo, 160-8582, Japan
| | - Misako Kunii
- Department of Neurology and Stroke Medicine, Yokohama City University Graduate School of Medicine, Yokohama, 236-0004, Japan
| | - Hideto Joki
- Department of Neurology and Stroke Medicine, Yokohama City University Graduate School of Medicine, Yokohama, 236-0004, Japan
- Department of Neurology, National Hospital Organization Yokohama Medical Center, Yokohama, Kanagawa, 245-8575, Japan
| | - Tatsuya Takahashi
- Department of Neurology, National Hospital Organization Yokohama Medical Center, Yokohama, Kanagawa, 245-8575, Japan
| | - Hiroyasu Komiya
- Department of Neurology and Stroke Medicine, Yokohama City University Graduate School of Medicine, Yokohama, 236-0004, Japan
| | - Mei Sasaki
- Department of Neurology, Yokohama Minami Kyosai Hospital, Yokohama, 236-0037, Japan
| | - Yosuke Miyaji
- Department of Neurology and Stroke Medicine, Yokohama City University Graduate School of Medicine, Yokohama, 236-0004, Japan
| | - Sachiko Ohori
- Department of Human Genetics, Yokohama City University Graduate School of Medicine, Yokohama, 236-0004, Japan
- Department of Clinical Genetics, Yokohama City University Hospital, Yokohama, 236-0004, Japan
- Department of Genetics, Kitasato University Hospital, Sagamihara, 252-0375, Japan
| | - Eriko Koshimizu
- Department of Human Genetics, Yokohama City University Graduate School of Medicine, Yokohama, 236-0004, Japan
| | - Yuri Uchiyama
- Department of Human Genetics, Yokohama City University Graduate School of Medicine, Yokohama, 236-0004, Japan
- Department of Rare Disease Genomics, Yokohama City University Hospital, Yokohama, 236-0004, Japan
| | - Naomi Tsuchida
- Department of Human Genetics, Yokohama City University Graduate School of Medicine, Yokohama, 236-0004, Japan
- Department of Rare Disease Genomics, Yokohama City University Hospital, Yokohama, 236-0004, Japan
| | - Atsushi Fujita
- Department of Human Genetics, Yokohama City University Graduate School of Medicine, Yokohama, 236-0004, Japan
| | - Kohei Hamanaka
- Department of Human Genetics, Yokohama City University Graduate School of Medicine, Yokohama, 236-0004, Japan
| | - Kazuharu Misawa
- Department of Human Genetics, Yokohama City University Graduate School of Medicine, Yokohama, 236-0004, Japan
- RIKEN Center for Advanced Intelligence Project, 1-4-1 Nihonbashi, Chuo-ku, Tokyo, 103-0027, Japan
| | - Satoko Miyatake
- Department of Human Genetics, Yokohama City University Graduate School of Medicine, Yokohama, 236-0004, Japan
- Department of Clinical Genetics, Yokohama City University Hospital, Yokohama, 236-0004, Japan
| | - Fumiaki Tanaka
- Department of Neurology and Stroke Medicine, Yokohama City University Graduate School of Medicine, Yokohama, 236-0004, Japan
| | - Naomichi Matsumoto
- Department of Human Genetics, Yokohama City University Graduate School of Medicine, Yokohama, 236-0004, Japan.
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Chen YJ, Wang MW, Qiu YS, Yuan RY, Wang N, Lin X, Chen WJ. Alu Retrotransposition Event in SPAST Gene as a Novel Cause of Hereditary Spastic Paraplegia. Mov Disord 2023; 38:1750-1755. [PMID: 37394769 DOI: 10.1002/mds.29522] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2023] [Revised: 06/05/2023] [Accepted: 06/12/2023] [Indexed: 07/04/2023] Open
Abstract
OBJECTIVES To diagnose the molecular cause of hereditary spastic paraplegia (HSP) observed in a four-generation family with autosomal dominant inheritance. METHODS Multiplex ligation-dependent probe amplification (MLPA), whole-exome sequencing (WES), and RNA sequencing (RNA-seq) of peripheral blood leukocytes were performed. Reverse transcription polymerase chain reaction (RT-PCR) and Sanger sequencing were used to characterize target regions of SPAST. RESULTS A 121-bp AluYb9 insertion with a 30-bp poly-A tail flanked by 15-bp direct repeats on both sides was identified in the edge of intron 16 in SPAST that segregated with the disease phenotype. CONCLUSIONS We identified an intronic AluYb9 insertion inducing splicing alteration in SPAST causing pure HSP phenotype that was not detected by routine WES analysis. Our findings suggest RNA-seq is a recommended implementation for undiagnosed cases by first-line diagnostic approaches. © 2023 International Parkinson and Movement Disorder Society.
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Affiliation(s)
- Yi-Jun Chen
- Department of Neurology and Institute of Neurology, The First Affiliated Hospital of Fujian Medical University, Fuzhou, China
- Department of Geriatrics, The First Affiliated Hospital of Fujian Medical University, Fuzhou, China
- Department of Geriatrics, National Regional Medical Center, Binhai Campus of the First Affiliated Hospital, Fujian Medical University, Fuzhou, China
| | - Meng-Wen Wang
- Department of Neurology and Institute of Neurology, The First Affiliated Hospital of Fujian Medical University, Fuzhou, China
| | - Yu-Sen Qiu
- Department of Neurology and Institute of Neurology, The First Affiliated Hospital of Fujian Medical University, Fuzhou, China
| | - Ru-Ying Yuan
- Department of Neurology and Institute of Neurology, The First Affiliated Hospital of Fujian Medical University, Fuzhou, China
| | - Ning Wang
- Department of Neurology and Institute of Neurology, The First Affiliated Hospital of Fujian Medical University, Fuzhou, China
- Fujian Key Laboratory of Molecular Neurology, Fujian Medical University, Fuzhou, China
| | - Xiang Lin
- Department of Neurology and Institute of Neurology, The First Affiliated Hospital of Fujian Medical University, Fuzhou, China
- Fujian Key Laboratory of Molecular Neurology, Fujian Medical University, Fuzhou, China
| | - Wan-Jin Chen
- Department of Neurology and Institute of Neurology, The First Affiliated Hospital of Fujian Medical University, Fuzhou, China
- Fujian Key Laboratory of Molecular Neurology, Fujian Medical University, Fuzhou, China
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Chen X, Li X, Tan Y, Yang D, Lu L, Deng Y, Xu R. Identification of c.1495C > T mutation in SPAST gene in a family of Han Chinese with hereditary spastic paraplegia. Neurosci Lett 2023; 812:137399. [PMID: 37473796 DOI: 10.1016/j.neulet.2023.137399] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2023] [Revised: 07/10/2023] [Accepted: 07/13/2023] [Indexed: 07/22/2023]
Abstract
BACKGROUND Hereditary spastic paraplegia 4 (SPG4) caused by spastin (SPAST) gene mutations accounts for 40-45% of hereditary spastic paraplegia (HSP) cases. To search for more genetic evidences for the pathogenesis of HSP, the SPAST genotype and clinical phenotype of a Chinese Han SPG4 family were analysed in this study. METHODS The clinical data of the proband and his family members were collected. Whole genomic DNA was extracted from peripheral blood, and the gene detection and pathogenicity analysis of mutations were conducted using whole-exome sequencing technology. Suspected pathogenic mutations were identified. Verification within this family was conducted by Sanger sequencing. RESULTS Eight (4 males and 4 females) of 20 members in 4 generations had SPG4. All patients presented with the high feet arches (pes cavus), the abnormal gait, the active tendon reflexes of the upper limbs, the hyperreflexia of the lower limbs, and the positive ankle clonus and Babinski's signs bilaterally. In the proband, we found a heterozygous mutation c.1495C > T in SPAST gene, which was associated with the autosomal dominant SPG4. Both the daughters and granddaughters of the proband in this family were verified to carry this mutation. The clinical characteristics of the SPG4 patients in this family are in line with the simple type of HSP. Heterozygous c.1495C > T is a pathogenic mutation in this family. CONCLUSION In this study, we identified a c.1495C > T mutation in the SPAST gene in a Han Chinese family, enriching the mutation spectrum of SPG4.
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Affiliation(s)
- Xiaohong Chen
- Department of Neurology, The First Hospital of Nanchang, Nanchang 330006, Jiangxi, China
| | - Xinming Li
- Department of Neurology, The First Hospital of Nanchang, Nanchang 330006, Jiangxi, China
| | - Yu Tan
- Department of Neurology, The First Hospital of Nanchang, Nanchang 330006, Jiangxi, China
| | - Dejiang Yang
- Department of Neurology, The First Hospital of Nanchang, Nanchang 330006, Jiangxi, China
| | - Lijun Lu
- Department of Neurology, The First Hospital of Nanchang, Nanchang 330006, Jiangxi, China
| | - Youqing Deng
- Department of Neurology, The First Hospital of Nanchang, Nanchang 330006, Jiangxi, China.
| | - Renshi Xu
- Department of Neurology, Jiangxi Provincial People's Hospital, The Clinical College of Nanchang College, The First Affiliated Hospital of Nanchang College, Nanchang 330006, Jiangxi, China.
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Saffari A, Ebrahimi-Fakhari D. Reply to: Early-Onset and Severe Complex Hereditary Spastic Paraplegia Caused by De Novo Variants in SPAST. Mov Disord 2023; 38:911-913. [PMID: 37303094 PMCID: PMC11049670 DOI: 10.1002/mds.29384] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2023] [Accepted: 02/24/2023] [Indexed: 06/13/2023] Open
Affiliation(s)
- Afshin Saffari
- Movement Disorders Program, Department of Neurology, Boston
Children’s Hospital, Harvard Medical School, Boston, MA, USA
| | - Darius Ebrahimi-Fakhari
- Movement Disorders Program, Department of Neurology, Boston
Children’s Hospital, Harvard Medical School, Boston, MA, USA
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11
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Cheers SR, O'Connor AE, Johnson TK, Merriner DJ, O'Bryan MK, Dunleavy JEM. Spastin is an essential regulator of male meiosis, acrosome formation, manchette structure and nuclear integrity. Development 2023; 150:297467. [PMID: 36971361 PMCID: PMC10112905 DOI: 10.1242/dev.201183] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2022] [Accepted: 02/24/2023] [Indexed: 03/29/2023]
Abstract
The development and function of male gametes is critically dependent on a dynamic microtubule network, yet how this is regulated remains poorly understood. We have recently shown that microtubule severing, via the action of the meiotic AAA ATPase protein clade, plays a critical role in this process. Here, we sought to elucidate the roles of spastin, an as yet unexplored member of this clade in spermatogenesis. Using a SpastKO/KO mouse model, we reveal that spastin loss resulted in a complete loss of functional germ cells. Spastin plays a critical role in the assembly and function of the male meiotic spindle. Consistent with meiotic failure, round spermatid nuclei were enlarged, indicating aneuploidy, but were still able to enter spermiogenesis. During spermiogenesis, we observed extreme abnormalities in manchette structure, acrosome biogenesis, and commonly, a catastrophic loss of nuclear integrity. This work defines a novel and essential role for spastin in regulating microtubule dynamics during spermatogenesis and is of potential relevance to patients carrying spastin variants and the medically assisted reproductive technology industry.
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Affiliation(s)
- Samuel R. Cheers
- School of BioSciences and Bio21 Institute, The University of Melbourne, Parkville, VIC 3010, Australia
| | - Anne E. O'Connor
- School of BioSciences and Bio21 Institute, The University of Melbourne, Parkville, VIC 3010, Australia
| | - Travis K. Johnson
- School of Biological Sciences, Monash University, Clayton, VIC 3800, Australia
| | - D. Jo Merriner
- School of BioSciences and Bio21 Institute, The University of Melbourne, Parkville, VIC 3010, Australia
| | - Moira K. O'Bryan
- School of BioSciences and Bio21 Institute, The University of Melbourne, Parkville, VIC 3010, Australia
- Authors for correspondence (; )
| | - Jessica E. M. Dunleavy
- School of BioSciences and Bio21 Institute, The University of Melbourne, Parkville, VIC 3010, Australia
- Authors for correspondence (; )
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Leighton DJ, Ansari M, Newton J, Parry D, Cleary E, Colville S, Stephenson L, Larraz J, Johnson M, Beswick E, Wong M, Gregory J, Carod Artal J, Davenport R, Duncan C, Morrison I, Smith C, Swingler R, Deary IJ, Porteous M, Aitman TJ, Chandran S, Gorrie GH, Pal S. Genotype-phenotype characterisation of long survivors with motor neuron disease in Scotland. J Neurol 2023; 270:1702-1712. [PMID: 36515702 PMCID: PMC9971124 DOI: 10.1007/s00415-022-11505-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2022] [Revised: 11/25/2022] [Accepted: 11/27/2022] [Indexed: 12/15/2022]
Abstract
BACKGROUND We investigated the phenotypes and genotypes of a cohort of 'long-surviving' individuals with motor neuron disease (MND) to identify potential targets for prognostication. METHODS Patients were recruited via the Clinical Audit Research and Evaluation for MND (CARE-MND) platform, which hosts the Scottish MND Register. Long survival was defined as > 8 years from diagnosis. 11 phenotypic variables were analysed. Whole genome sequencing (WGS) was performed and variants within 49 MND-associated genes examined. Each individual was screened for C9orf72 repeat expansions. Data from ancestry-matched Scottish populations (the Lothian Birth Cohorts) were used as controls. RESULTS 58 long survivors were identified. Median survival from diagnosis was 15.5 years. Long survivors were significantly younger at onset and diagnosis than incident patients and had a significantly longer diagnostic delay. 42% had the MND subtype of primary lateral sclerosis (PLS). WGS was performed in 46 individuals: 14 (30.4%) had a potentially pathogenic variant. 4 carried the known SOD1 p.(Ile114Thr) variant. Significant variants in FIG4, hnRNPA2B1, SETX, SQSTM1, TAF15, and VAPB were detected. 2 individuals had a variant in the SPAST gene suggesting phenotypic overlap with hereditary spastic paraplegia (HSP). No long survivors had pathogenic C9orf72 repeat expansions. CONCLUSIONS Long survivors are characterised by younger age at onset, increased prevalence of PLS and longer diagnostic delay. Genetic analysis in this cohort has improved our understanding of the phenotypes associated with the SOD1 variant p.(Ile114Thr). Our findings confirm that pathogenic expansion of C9orf72 is likely a poor prognostic marker. Genetic screening using targeted MND and/or HSP panels should be considered in those with long survival, or early-onset slowly progressive disease, to improve diagnostic accuracy and aid prognostication.
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Affiliation(s)
- Danielle J Leighton
- School of Psychology & Neuroscience, University of Glasgow, Glasgow, UK.
- Euan MacDonald Centre for Motor Neuron Disease Research, University of Edinburgh, Edinburgh, UK.
- Anne Rowling Regenerative Neurology Clinic, Royal Infirmary, Edinburgh, UK.
- Centre for Clinical Brain Sciences, University of Edinburgh, Edinburgh, UK.
- Institute of Neurological Sciences, Queen Elizabeth University Hospital, Glasgow, UK.
| | - Morad Ansari
- South East Scotland Genetics Service, Western General Hospital, Edinburgh, UK
| | - Judith Newton
- Euan MacDonald Centre for Motor Neuron Disease Research, University of Edinburgh, Edinburgh, UK
- Anne Rowling Regenerative Neurology Clinic, Royal Infirmary, Edinburgh, UK
- Centre for Clinical Brain Sciences, University of Edinburgh, Edinburgh, UK
| | - David Parry
- Centre for Genomic and Experimental Medicine, Institute of Genetics and Cancer, University of Edinburgh, Edinburgh, UK
| | - Elaine Cleary
- South East Scotland Genetics Service, Western General Hospital, Edinburgh, UK
| | - Shuna Colville
- Euan MacDonald Centre for Motor Neuron Disease Research, University of Edinburgh, Edinburgh, UK
- Anne Rowling Regenerative Neurology Clinic, Royal Infirmary, Edinburgh, UK
- Centre for Clinical Brain Sciences, University of Edinburgh, Edinburgh, UK
| | - Laura Stephenson
- Euan MacDonald Centre for Motor Neuron Disease Research, University of Edinburgh, Edinburgh, UK
| | - Juan Larraz
- Anne Rowling Regenerative Neurology Clinic, Royal Infirmary, Edinburgh, UK
| | - Micheala Johnson
- Anne Rowling Regenerative Neurology Clinic, Royal Infirmary, Edinburgh, UK
| | - Emily Beswick
- Anne Rowling Regenerative Neurology Clinic, Royal Infirmary, Edinburgh, UK
| | - Michael Wong
- Anne Rowling Regenerative Neurology Clinic, Royal Infirmary, Edinburgh, UK
| | - Jenna Gregory
- Euan MacDonald Centre for Motor Neuron Disease Research, University of Edinburgh, Edinburgh, UK
- Centre for Genomic and Experimental Medicine, Institute of Genetics and Cancer, University of Edinburgh, Edinburgh, UK
- Institute of Medical Sciences, University of Aberdeen, Aberdeen, UK
| | | | - Richard Davenport
- Euan MacDonald Centre for Motor Neuron Disease Research, University of Edinburgh, Edinburgh, UK
- Anne Rowling Regenerative Neurology Clinic, Royal Infirmary, Edinburgh, UK
| | - Callum Duncan
- Department of Neurology, Aberdeen Royal Infirmary, Aberdeen, UK
| | - Ian Morrison
- Department of Neurology, NHS Tayside, Dundee, UK
| | - Colin Smith
- Euan MacDonald Centre for Motor Neuron Disease Research, University of Edinburgh, Edinburgh, UK
- Centre for Genomic and Experimental Medicine, Institute of Genetics and Cancer, University of Edinburgh, Edinburgh, UK
| | - Robert Swingler
- Euan MacDonald Centre for Motor Neuron Disease Research, University of Edinburgh, Edinburgh, UK
| | - Ian J Deary
- Lothian Birth Cohorts Group, Department of Psychology, University of Edinburgh, Edinburgh, UK
| | - Mary Porteous
- South East Scotland Genetics Service, Western General Hospital, Edinburgh, UK
| | - Timothy J Aitman
- Centre for Genomic and Experimental Medicine, Institute of Genetics and Cancer, University of Edinburgh, Edinburgh, UK
| | - Siddharthan Chandran
- Euan MacDonald Centre for Motor Neuron Disease Research, University of Edinburgh, Edinburgh, UK
- Anne Rowling Regenerative Neurology Clinic, Royal Infirmary, Edinburgh, UK
- Centre for Clinical Brain Sciences, University of Edinburgh, Edinburgh, UK
- UK Dementia Research Institute, University of Edinburgh, Edinburgh, UK
| | - George H Gorrie
- Euan MacDonald Centre for Motor Neuron Disease Research, University of Edinburgh, Edinburgh, UK
- Institute of Neurological Sciences, Queen Elizabeth University Hospital, Glasgow, UK
| | - Suvankar Pal
- Euan MacDonald Centre for Motor Neuron Disease Research, University of Edinburgh, Edinburgh, UK
- Anne Rowling Regenerative Neurology Clinic, Royal Infirmary, Edinburgh, UK
- Centre for Clinical Brain Sciences, University of Edinburgh, Edinburgh, UK
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13
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Mo A, Saffari A, Kellner M, Döbler-Neumann M, Jordan C, Srivastava S, Zhang B, Sahin M, Fink JK, Smith L, Posey JE, Alter KE, Toro C, Blackstone C, Soldatos AG, Christie M, Schüle R, Ebrahimi-Fakhari D. Early-Onset and Severe Complex Hereditary Spastic Paraplegia Caused by De Novo Variants in SPAST. Mov Disord 2022; 37:2440-2446. [PMID: 36103453 PMCID: PMC10062395 DOI: 10.1002/mds.29225] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2022] [Revised: 08/13/2022] [Accepted: 08/26/2022] [Indexed: 01/13/2023] Open
Abstract
BACKGROUND Familial hereditary spastic paraplegia (HSP)-SPAST (SPG4) typically presents with a pure HSP phenotype. OBJECTIVE The aim of this study was to delineate the genotypic and phenotypic spectrum of children with de novo HSP-SPAST. METHODS This study used a systematic cross-sectional analysis of clinical and molecular features. RESULTS We report the clinical and molecular spectrum of 40 patients with heterozygous pathogenic de novo variants in SPAST (age range: 2.2-27.7 years). We identified 19 unique variants (16/40 carried the same recurrent variant, p.Arg499His). Symptom onset was in early childhood (median: 11.0 months, interquartile range: 6.0 months) with significant motor and speech delay, followed by progressive ascending spasticity, dystonia, neurogenic bladder dysfunction, gastrointestinal dysmotility, and epilepsy. The mean Spastic Paraplegia Rating Scale score was 32.8 ± 9.7 (standard deviation). CONCLUSIONS These results confirm that de novo variants in SPAST lead to a severe and complex form of HSP that differs from classic familial pure HSP-SPAST. Clinicians should be aware of this syndrome in the differential diagnosis for cerebral palsy. © 2022 International Parkinson and Movement Disorder Society.
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Affiliation(s)
- Alisa Mo
- Department of Neurology, Boston Children’s Hospital, Harvard Medical School, Boston, MA, USA
| | - Afshin Saffari
- Department of Neurology, Boston Children’s Hospital, Harvard Medical School, Boston, MA, USA
| | - Melanie Kellner
- Department of Neurodegenerative Diseases, Hertie Institute for Clinical Brain Research and Center of Neurology, University of Tübingen, Tübingen, Germany
- German Center for Neurodegenerative Diseases (DZNE), Tübingen, Germany
| | - Marion Döbler-Neumann
- Department of Pediatric Neurology, University Children’s Hospital, Tübingen, Germany
| | - Catherine Jordan
- Department of Neurology, Boston Children’s Hospital, Harvard Medical School, Boston, MA, USA
| | - Siddharth Srivastava
- Department of Neurology, Boston Children’s Hospital, Harvard Medical School, Boston, MA, USA
| | - Bo Zhang
- Department of Neurology, Boston Children’s Hospital, Harvard Medical School, Boston, MA, USA
- ICCTR Biostatistics and Research Design Center, Boston Children’s Hospital, Harvard Medical School, Boston, MA
| | - Mustafa Sahin
- Department of Neurology, Boston Children’s Hospital, Harvard Medical School, Boston, MA, USA
| | - John K. Fink
- Department of Neurology, University of Michigan, Ann Arbor, MI, USA
| | - Linsley Smith
- Department of Neurology and Rehabilitation Medicine, Texas Scottish Rite Hospital, University of Texas Southwestern Medical Center, Dallas, TX, 75219, USA
| | - Jennifer E. Posey
- Department of Molecular & Human Genetics, Baylor College of Medicine, Houston, TX, USA
| | - Katharine E. Alter
- Functional and Applied Biomechanics Section, Department of Rehabilitation Medicine, Clinical Center, National Institutes of Health, Bethesda, MD, USA
| | - Camilo Toro
- Undiagnosed Diseases Program, National Institutes of Health, Bethesda, MD, USA
| | - Craig Blackstone
- Movement Disorders Division, Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - Ariane G. Soldatos
- National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, USA
| | - Michelle Christie
- Department of Neurology and Rehabilitation Medicine, Texas Scottish Rite Hospital, University of Texas Southwestern Medical Center, Dallas, TX, 75219, USA
| | - Rebecca Schüle
- Department of Neurodegenerative Diseases, Hertie Institute for Clinical Brain Research and Center of Neurology, University of Tübingen, Tübingen, Germany
- German Center for Neurodegenerative Diseases (DZNE), Tübingen, Germany
| | - Darius Ebrahimi-Fakhari
- Department of Neurology, Boston Children’s Hospital, Harvard Medical School, Boston, MA, USA
- Movement Disorders Program, Department of Neurology, Boston Children’s Hospital, Harvard Medical School, Boston, MA, USA
- The Manton Center for Orphan Disease Research, Boston Children’s Hospital, Boston, MA, USA
- Intellectual and Developmental Disabilities Research Center, Boston Children’s Hospital, Boston, MA, USA
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14
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Zhang LP, Wang YF. [A novel mutation of SPAST gene in a hereditary spastic paraplegia type 4 family]. Zhonghua Nei Ke Za Zhi 2022; 61:1343-1350. [PMID: 36456515 DOI: 10.3760/cma.j.cn112138-20220912-00675] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/17/2023]
Abstract
Objective: To clarify the pathogenicity and further explore the association between genotype and clinical phenotype of this variant, analyzing a novel variation of SPAST gene in hereditary spastic paraplegia (HSP) family from Changzhi city, Shanxi Province. Methods: A family with HSP was tracked and collected in Neurology Department of Heping Hospital Affiliated to Changzhi Medical College in October 2019. Peripheral venous blood of 2 ml was extracted from the proband and 8 other members of the family, genomic DNA was extracted from the blood samples, and the genes of spastic paraplegia were screened by next-generation sequencing (NGS). HGMD, 1000G, OMIM databases and PolyPhen2, SIFT and other software were used for bioinformatics analysis of suspected mutations. Multiplex ligation-dependent probe amplification (MLPA) was used to further screen for total deletions/duplications in patients who remained negative after targeting NGS, and Sanger sequencing was performed to verify the suspected pathogenic mutation sites in the family to determine co-isolation of the mutation sites in the family members. Finally, it is necessary to refer to the latest version of The American College of Medical Genetics and Genomics (ACMG) sequence variation interpretation guidelines to interpret the mutation sites to determine pathogenicity. Results: The HSP family consist 47 members of 4 generations and 10 patients, with onset ages ranging from 2 to 44 years. The proband's daughter only showed positive bilateral Babbitt signs on physical examination, and the rest of the patients showed spasticity and weakness of lower limbs with varying severity on this basis. Preliminary screening by next-generation sequencing technology showed that the proband had frame-shift variation of SPAST gene c.1057_1058insCC (p.Leu354HisfsTer11) and missense variation of DCTN1 gene c.2213A>G (p.Gln738Arg). Then, Sanger sequencing was used for in-family verification, which showed SPAST gene c.1057_1058insCC (p.Leu354HisfsTer11) was detected in the affected members include father, brother, son and daughter, and not detected in the unaffected normal members, the proband's wife, mother, sister and sister-in-law. However, the unaffected of mother detected missense variation of DCTN1 gene c.2213A>G (p.Gln738Arg), while the remaining members did not detect this variation. The results of MLPA showed that no large fragment variation was found. Conclusions: The genetic pattern of the HSP family was autosomal dominant, and the clinical characteristics were consistent with hereditary spastic paraplegia type 4 (SPG4). Co-segregation of SPAST gene c.1057_1058insCC (p.Leu354HisfsTer11) was found in the HSP family and was the pathogenicity cause of this SPG4 family, and it was a newly discovered mutation locus.
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Affiliation(s)
- L P Zhang
- Department of Neurology, Heping Hospital Affiliated to Changzhi Medical College, Changzhi 046000,China
| | - Y F Wang
- Department of Neurology, Heping Hospital Affiliated to Changzhi Medical College, Changzhi 046000,China
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15
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Zhu PP, Hung HF, Batchenkova N, Nixon-Abell J, Henderson J, Zheng P, Renvoisé B, Pang S, Xu CS, Saalfeld S, Funke J, Xie Y, Svara F, Hess HF, Blackstone C. Transverse endoplasmic reticulum expansion in hereditary spastic paraplegia corticospinal axons. Hum Mol Genet 2022; 31:2779-2795. [PMID: 35348668 PMCID: PMC9402237 DOI: 10.1093/hmg/ddac072] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2021] [Revised: 03/15/2022] [Accepted: 03/20/2022] [Indexed: 08/12/2023] Open
Abstract
Hereditary spastic paraplegias (HSPs) comprise a large group of inherited neurologic disorders affecting the longest corticospinal axons (SPG1-86 plus others), with shared manifestations of lower extremity spasticity and gait impairment. Common autosomal dominant HSPs are caused by mutations in genes encoding the microtubule-severing ATPase spastin (SPAST; SPG4), the membrane-bound GTPase atlastin-1 (ATL1; SPG3A) and the reticulon-like, microtubule-binding protein REEP1 (REEP1; SPG31). These proteins bind one another and function in shaping the tubular endoplasmic reticulum (ER) network. Typically, mouse models of HSPs have mild, later onset phenotypes, possibly reflecting far shorter lengths of their corticospinal axons relative to humans. Here, we have generated a robust, double mutant mouse model of HSP in which atlastin-1 is genetically modified with a K80A knock-in (KI) missense change that abolishes its GTPase activity, whereas its binding partner Reep1 is knocked out. Atl1KI/KI/Reep1-/- mice exhibit early onset and rapidly progressive declines in several motor function tests. Also, ER in mutant corticospinal axons dramatically expands transversely and periodically in a mutation dosage-dependent manner to create a ladder-like appearance, on the basis of reconstructions of focused ion beam-scanning electron microscopy datasets using machine learning-based auto-segmentation. In lockstep with changes in ER morphology, axonal mitochondria are fragmented and proportions of hypophosphorylated neurofilament H and M subunits are dramatically increased in Atl1KI/KI/Reep1-/- spinal cord. Co-occurrence of these findings links ER morphology changes to alterations in mitochondrial morphology and cytoskeletal organization. Atl1KI/KI/Reep1-/- mice represent an early onset rodent HSP model with robust behavioral and cellular readouts for testing novel therapies.
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Affiliation(s)
- Peng-Peng Zhu
- Neurogenetics Branch, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD 20892, USA
| | - Hui-Fang Hung
- Neurogenetics Branch, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD 20892, USA
- MassGeneral Institute for Neurodegenerative Disease, Charlestown, MA 02129, USA
- Department of Neurology, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114, USA
| | - Natalia Batchenkova
- Neurogenetics Branch, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD 20892, USA
| | - Jonathon Nixon-Abell
- Neurogenetics Branch, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD 20892, USA
- Howard Hughes Medical Institute, Janelia Research Campus, Ashburn, VA 20147, USA
- Cambridge Institute for Medical Research, Cambridge CB2 0XY, UK
| | - James Henderson
- Cambridge Institute for Medical Research, Cambridge CB2 0XY, UK
| | - Pengli Zheng
- Neurogenetics Branch, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD 20892, USA
- MassGeneral Institute for Neurodegenerative Disease, Charlestown, MA 02129, USA
- Department of Neurology, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114, USA
| | - Benoit Renvoisé
- Neurogenetics Branch, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD 20892, USA
| | - Song Pang
- Howard Hughes Medical Institute, Janelia Research Campus, Ashburn, VA 20147, USA
| | - C Shan Xu
- Howard Hughes Medical Institute, Janelia Research Campus, Ashburn, VA 20147, USA
| | - Stephan Saalfeld
- Howard Hughes Medical Institute, Janelia Research Campus, Ashburn, VA 20147, USA
| | - Jan Funke
- Howard Hughes Medical Institute, Janelia Research Campus, Ashburn, VA 20147, USA
| | - Yuxiang Xie
- Synaptic Function Section, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD 20892, USA
| | - Fabian Svara
- ariadne.ai ag, CH-6033 Buchrain, Switzerland
- Research Center Caesar, D-53175 Bonn, Germany
| | - Harald F Hess
- Howard Hughes Medical Institute, Janelia Research Campus, Ashburn, VA 20147, USA
| | - Craig Blackstone
- Neurogenetics Branch, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD 20892, USA
- MassGeneral Institute for Neurodegenerative Disease, Charlestown, MA 02129, USA
- Department of Neurology, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114, USA
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16
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Panwala TF, Garcia-Santibanez R, Vizcarra JA, Garcia AG, Verma S. Childhood-Onset Hereditary Spastic Paraplegia (HSP): A Case Series and Review of Literature. Pediatr Neurol 2022; 130:7-13. [PMID: 35303589 DOI: 10.1016/j.pediatrneurol.2022.02.007] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/08/2021] [Revised: 01/30/2022] [Accepted: 02/25/2022] [Indexed: 11/17/2022]
Abstract
BACKGROUND Hereditary spastic paraplegia (HSP) encompasses several rare genetic disorders characterized by progressive lower extremity spasticity and weakness caused by corticospinal tract degeneration. Published literature on genetically confirmed pediatric HSP cases is limited. METHODS We conducted a retrospective review of childhood-onset HSP cases followed in the neuromuscular clinics at Children's and Emory Healthcare in Atlanta. Clinical presentation, family history, examination, electrodiagnostic data, neuroimaging, genetic test results, comorbidities, and treatment were recorded. RESULTS Sixteen patients with HSP (eight males, eight females) with a mean age 19 years ± 15.7 years were included. Ten patients (66%) presented with gait difficulty. Seven (44%) were ambulatory at the last clinic follow-up visit with an average disease duration of 7.4 years. Genetically confirmed etiologies included SPAST (3 patients), MARS (2), KIF1A (2), KIF5A (1), SACS (1), SPG7 (1), REEP1 (1), PNPT1 (1), MT-ATP6 (1), and ATL1 (1). Symptom onset to genetic confirmation on an average was 8.2 years. Sensory motor axonal polyneuropathy was found in seven patients, and two exhibited cerebellar atrophy on magnetic resonance imaging (MRI) of the brain. Neurological comorbidities included developmental delay (n = 9), autism (n = 5), epilepsy (n = 3), and attention-deficit/hyperactivity disorder (n = 2). CONCLUSIONS In our study, a significant proportion (70%) of subjects with childhood-onset HSP had comorbid neurocognitive deficits, polyneuropathy with or without neuroimaging abnormalities, and rare genetic etiology. Genetic diagnosis was established either through inherited genetic neuropathy panel or whole-exome sequencing, which supports the utility of whole-exome sequencing in aiding in HSP diagnosis.
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Affiliation(s)
- Tanya F Panwala
- Florida Atlantic University, Charles E. Schmidt College of Medicine, Boca Raton, Florida
| | | | - Joaquin A Vizcarra
- Department of Neurology, Emory University School of Medicine, Atlanta, Georgia
| | - Aixa Gonzalez Garcia
- Department of Pediatrics, Genetics Section, University of Arkansas for Medical Sciences and Arkansas Children's Hospital, Little Rock, Arkansas
| | - Sumit Verma
- Department of Neurology, Emory University School of Medicine, Atlanta, Georgia; Division of Pediatric Neurology, Children's Healthcare of Atlanta and Emory University School of Medicine, Atlanta, Georgia.
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17
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Verriello L, Lonigro IR, Pessa ME, Betto E, Pauletto G, Fogolari F, Gigli GL, Curcio F. Amplifying the spectrum of SPAST gene mutations. Acta Biomed 2021; 92:e2021220. [PMID: 35132972 PMCID: PMC10523053 DOI: 10.23750/abm.v92is1.11608] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Received: 04/12/2021] [Accepted: 04/13/2021] [Indexed: 06/14/2023]
Abstract
Hereditary spastic paraplegias (HSPs) include a group of neurodegenerative disorders characterized by slowly progressive spasticity and weakness of the lower extremities, caused by axon degeneration of corticospinal tracts. Spastic paraplegia type 4 (SPG4) is the most common autosomal dominant form of HSP and is caused by mutations in the SPAST gene. SPAST gene encodes for the protein spastin, a member of the ATPases Associated with a variety of cellular Activity (AAA) family.We describe a newly variant in SPAST gene, within an Italian family affected by pure HSP. In particular, we found a heterozygous intragenic microdeletion of 3T in exon 13 of SPG4 gene. The 3T deletion results in a mutated protein with a unique leucine residues deletion at the protein position 508, in the AAA ATPase domain. This variant is not registered in any public database either as rare normal variant nor as mutation in SPAST gene and the importance of this aminoacid is confirmed by the absolute conservation in multiple alignments with diverse species. We conclude that the novel SPAST gene variant identified is probably pathogenic and destabilizes the precise arrangement of the nucleotide binding domain, with a consequent loss-of-function of the mutated spastin protein.
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Affiliation(s)
- Lorenzo Verriello
- Neurology Unit, Department of Neurosciences, Santa Maria della Misericordia University Hospital, ASUFC, Udine, Italy.
| | - Incoronata Renata Lonigro
- Institute of Clinical Pathology, Santa Maria della Misericordia University Hospital, ASUFC, Udine, Italy.
| | - Maria Elena Pessa
- a:1:{s:5:"en_US";s:49:"Azienda ospedaliero universitaria Friuli centrale";}.
| | - Elena Betto
- Institute of Clinical Pathology, Santa Maria della Misericordia University Hospital, ASUFC, Udine, Italy.
| | - Giada Pauletto
- Neurology Unit, Department of Neurosciences, Santa Maria della Misericordia University Hospital, ASUFC, Udine, Italy.
| | - Federico Fogolari
- Department of Mathematics, Informatics and Physics (DMIF), University of Udine, Italy.
| | - Gian Luigi Gigli
- Clinical Neurology Unit, Department of Neurosciences, Santa Maria della Misericordia University Hospital, ASUFC, Udine, Italy.
| | - Francesco Curcio
- Institute of Clinical Pathology, Santa Maria della Misericordia University Hospital, ASUFC, Udine, Italy.
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18
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Angelini C, Goizet C, Said SA, Camu W, Depienne C, Heron B, Kol B, Guillaud-Bataille M, Pennamen P, Rooryck C, Scherer-Gagou C, Tissier L, Stevanin G, Leguern E, Banneau G. Evidence of mosaicism in SPAST variant carriers in four French families. Eur J Hum Genet 2021; 29:1158-1163. [PMID: 33958741 PMCID: PMC8298572 DOI: 10.1038/s41431-021-00847-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2020] [Revised: 02/14/2021] [Accepted: 02/24/2021] [Indexed: 11/08/2022] Open
Abstract
Hereditary spastic paraplegias (HSP) are heterogeneous disorders, with more than 70 causative genes. Variants in SPAST are the most frequent genetic etiology and are responsible for spastic paraplegia type 4 (SPG4). Age at onset can vary, even between patients from the same family, and incomplete penetrance is described. Somatic mosaicism is extremely rare with only three patients reported in the literature. We report here SPAST mosaic variants in four unrelated patients. We confirm that mosaicism in SPAST is a very rare event with only four identified cases on more than 300 patients with a SPAST variant previously described by our clinical diagnostic laboratory.
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Affiliation(s)
- Chloé Angelini
- Service de Génétique Médicale, CHU Bordeaux, Bordeaux, Bordeaux, France
- Centre de Référence Maladies Rares Neurogénétique, Service de Génétique Médicale, Bordeaux, France
| | - Cyril Goizet
- Service de Génétique Médicale, CHU Bordeaux, Bordeaux, Bordeaux, France
- Centre de Référence Maladies Rares Neurogénétique, Service de Génétique Médicale, Bordeaux, France
- INSERM U1211, laboratoire MRGM, Univ. Bordeaux, Bordeaux, France
| | - Samia Ait Said
- Sorbonne Université, AP-HP, GH Pitié-Salpêtrière, Département de génétique, Paris, France
| | - William Camu
- Centre de référence SLA, explorations neurologiques, CHU et Univ Montpellier, Montpellier, France
| | - Christel Depienne
- Sorbonne Université, AP-HP, GH Pitié-Salpêtrière, Département de génétique, Paris, France
- Sorbonne université, Institut du Cerveau, INSERM U 1127, Paris, France
- Institute of Human Genetics, University Hospital Essen, University of Duisburg-Essen, Essen, Germany
| | - Bénédicte Heron
- Service de Neurologie Pédiatrique, Hôpital Armand Trousseau-La Roche Guyon, GHUEP, APHP, Paris, France
| | - Bophara Kol
- Sorbonne Université, AP-HP, GH Pitié-Salpêtrière, Département de génétique, Paris, France
| | | | - Perrine Pennamen
- Service de Génétique Médicale, CHU Bordeaux, Bordeaux, Bordeaux, France
- INSERM U1211, laboratoire MRGM, Univ. Bordeaux, Bordeaux, France
| | - Caroline Rooryck
- Service de Génétique Médicale, CHU Bordeaux, Bordeaux, Bordeaux, France
- INSERM U1211, laboratoire MRGM, Univ. Bordeaux, Bordeaux, France
| | - Clarisse Scherer-Gagou
- Centre National de Référence pour les Maladies Neurogénétiques de l'Adulte, Département de Neurologie, Centre Hospitalier Universitaire d'Angers, Angers, France
| | - Laurène Tissier
- Sorbonne Université, AP-HP, GH Pitié-Salpêtrière, Département de génétique, Paris, France
| | - Giovanni Stevanin
- Sorbonne Université, AP-HP, GH Pitié-Salpêtrière, Département de génétique, Paris, France
- Sorbonne université, Institut du Cerveau, INSERM U 1127, Paris, France
- Equipe de neurogénétique, Ecole Pratique des Hautes Etudes (EPHE), PSL Research University, Paris, France
| | - Eric Leguern
- Sorbonne Université, AP-HP, GH Pitié-Salpêtrière, Département de génétique, Paris, France.
- Sorbonne université, Institut du Cerveau, INSERM U 1127, Paris, France.
| | - Guillaume Banneau
- Sorbonne Université, AP-HP, GH Pitié-Salpêtrière, Département de génétique, Paris, France
- Département de Génétique Médicale, Institut Fédératif de Biologie, Hôpital Purpan, Toulouse, France
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Qi N, Ma M, Yang K, Lou G, Qin L, Hou Q, Zhang Y, Liao S. [Identification of SPAST gene variant in a pedigree affected with hereditary spastic paraplegia type 4]. Zhonghua Yi Xue Yi Chuan Xue Za Zhi 2020; 37:1261-1264. [PMID: 33179235 DOI: 10.3760/cma.j.cn511374-20191120-00592] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
OBJECTIVE To explore the genetic basis for a pedigree affected with hereditary spastic paraplegia type 4 (HSP4). METHODS Peripheral venous blood samples were taken from members of the four-generation pedigree and 50 healthy controls for the extraction of genomic DNA. Genes associated with peripheral neuropathy and hereditary spastic paraplegia were captured and subjected to targeted capture and next-generation sequencing. The results were confirmed by Sanger sequencing. RESULTS DNA sequencing suggested that the proband has carried a heterozygous c.1196C>G variant in exon 9 of the SPAST gene, which can cause substitution of serine by threonine at position 399 (p.Ser399Trp) and lead to change in the protein function. The same variant was also detected in other patients from the pedigree but not among unaffected individuals or the 50 healthy controls. Based on the ACMG 2015 guidelines, the variant was predicted to be possibly pathogenic. CONCLUSION The c.1196C>G variant of the SPAST gene probably underlay the HSP4 in this pedigree.
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Affiliation(s)
- Na Qi
- Institute of Medical Genetics, Henan Provincial People's Hospital, Department of Neurology, Henan Provincial People's Hospital, Henan Provincial Key Laboratory of Genetic Diseases and Functional Genomics, National Health Commission Key Laboratory for Birth Defect Prevention, People's Hospital of Zhengzhou University, Zhengzhou, Henan 450003, China.1004946490@ qq.com
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20
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Nan H, Okamoto K, Gao L, Morishima Y, Ichinose Y, Koh K, Hashiyada M, Adachi N, Takiyama Y. A Japanese SPG4 Patient with a Confirmed De Novo Mutation of the SPAST Gene. Intern Med 2020; 59:2311-2315. [PMID: 32522921 PMCID: PMC7578612 DOI: 10.2169/internalmedicine.4599-20] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Spastic paraplegia type 4 (SPG4) is caused by mutations of the SPAST gene and is the most common form of autosomal-dominantly inherited pure hereditary spastic paraplegia (HSP). We herein report a Japanese patient with SPG4 with a confirmed de novo mutation of SPAST. On exome sequencing and Sanger sequencing, we identified the heterozygous missense mutation p.R460L in the SPAST gene. This mutation was absent in the parents, and the paternity and maternity of the parents were both confirmed. The patient showed a pure SPG4 phenotype with an infantile onset. This study may expand the clinical and genetic findings for SPG4.
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Affiliation(s)
- Haitian Nan
- Department of Neurology, Graduate School of Medical Sciences, University of Yamanashi, Japan
| | - Kensho Okamoto
- Department of Neurology, Ehime Prefectural Central Hospital, Japan
| | - Lihua Gao
- Department of Neurology, Graduate School of Medical Sciences, University of Yamanashi, Japan
| | - Yuto Morishima
- Department of Neurology, Graduate School of Medical Sciences, University of Yamanashi, Japan
| | - Yuta Ichinose
- Department of Neurology, Graduate School of Medical Sciences, University of Yamanashi, Japan
| | - Kishin Koh
- Department of Neurology, Graduate School of Medical Sciences, University of Yamanashi, Japan
| | | | - Noboru Adachi
- Department of Legal Medicine, Graduate School of Medical Sciences, University of Yamanashi, Japan
| | - Yoshihisa Takiyama
- Department of Neurology, Graduate School of Medical Sciences, University of Yamanashi, Japan
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21
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Xie Y, Xia Y, Sun Z, Gu L, Bai Z, Kong X. [Clinical characteristics and variant analysis of five pedigrees with hereditary spastic paraplegia]. Zhonghua Yi Xue Yi Chuan Xue Za Zhi 2020; 37:709-712. [PMID: 32619247 DOI: 10.3760/cma.j.issn.1003-9406.2020.07.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
OBJECTIVE To explore the clinical and genetic characteristics of five pedigrees affected with hereditary spastic paraplegia(HSP). METHODS Clinical data of the five pedigrees was collected, and high-throughput sequencing was carried out to detect potential variants. Sanger sequencing were used to verify the results. RESULTS The probands of pedigree 1 and 2 were found to harbor heterozygous SPAST gene variants, namely c.1196C>T and c.1523T>A. The proband of pedigree 3 harbored compound heterozygous variants of FA2H gene (c.61G>C and c.688G>A). Proband from pedigree 4 harbored compound heterozygous variants of SPG11 gene (c.6812+4_6812+7delAGTA and c.915delT). The proband of pedigree 5 harbored compound heterozygous variants of SPG7 gene (c.1703_1704delAG and c.1937-1G>C). Based on the American College of Medical Genetics and Genomics(ACMG) guidelines, all variants were predicted to be likely pathogenic. Among these, SPAST gene c.1523T>A, FA2H gene c.61.G>C, SPG11 gene splicing region c.6812+4_6812+7delAGTA, c.915delT, SPG7 gene c.1703_1704delAG and splicing region c.1937-1G>C variants were unreported previously. CONCLUSION The probands of pedigrees 1 and 2 were diagnosed with autosomal dominant hereditary spastic paraplegia type 4, for which pedigree 2 showed incompletely penetrance. Pedigrees 3, 4, and 5 were diagnosed with autosomal recessive hereditary spastic paraplegia type 35, 11 and 7, respectively. Above result provided a reference for clinical diagnosis and genetic counseling for the affected pedigrees.
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Affiliation(s)
- Yanchuan Xie
- Department of Central Laboratory, the First Affiliated Hospital and College of Clinical Medicine of Henan University of Science and Technology, Luoyang, Henan 471003, China.
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22
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Zhu Z, Zhang C, Zhao G, Liu Q, Zhong P, Zhang M, Tang W, Zhan F, Tian W, Wang Y, Yin K, Huang X, Jiang J, Liu X, Liu S, Zhou H, Luan X, Tang H, Wang Y, Chen S, Cao L. Novel mutations in the SPAST gene cause hereditary spastic paraplegia. Parkinsonism Relat Disord 2019; 69:125-133. [PMID: 31751864 DOI: 10.1016/j.parkreldis.2019.11.007] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/08/2019] [Revised: 10/05/2019] [Accepted: 11/05/2019] [Indexed: 01/14/2023]
Abstract
BACKGROUND Mutations in the SPAST gene are the most frequent cause of hereditary spastic paraplegia (HSP). We aim to extend the mutation spectrum of spastic paraplegia 4 (SPG4) and carried out experiment in vitro to explore the influence of the SPAST gene mutation on the function of corresponding protein. METHODS Whole-exome sequencing (WES) combined with multiplex ligation-dependent probe amplification (MLPA) were performed in a cohort of 150 patients clinically diagnosed with HSP. We focus on screening for mutations in SPAST gene and carrying out functional experiments to assess the effects of the novel variants. RESULTS A total of 34 different mutations in the SPAST gene were identified, of which 10 were novel, including 1 missense (c.1479T > A), 1 nonsense (c.766G > T), 3 splicing (c.1413 + 1_1413+4delGTAA, c.1729-1G > A and c.1536+2T > G) and 5 frameshift mutations (c.1094delC, c.885dupA, c.517_518delAG, c.280delG and c.908dupC). For 7 novel non-splicing mutations, functional study showed that accumulated M1 spastin colcocalized with microtubules which was different from a uniformly diffused M87 spastin. While an impairment in severing activity was observed in both mutant M1 and mutant M87, except for c.280delG. All 3 novel splicing variants w ere predicted to affect splicing by using bioinformatic programs. However, only c.1536+2T > G had no influence on splice site in vitro, which conflicts with the in-silico analysis. CONCLUSION We genetically diagnosed 40 SPG4 patients. All the novel non-splicing mutations except for c.280delG were certified to exert an effect on the microtubule-severing and all the novel splicing mutations other than c.1536+2T > G would cause abnormal splicing of the spastin.
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Affiliation(s)
- Zeyu Zhu
- Department of Neurology and Institute of Neurology, Rui Jin Hospital & Rui Jin Hospital North, Shanghai Jiao Tong University School of Medicine, Shanghai, China.
| | - Chao Zhang
- Department of Neurology and Institute of Neurology, Rui Jin Hospital & Rui Jin Hospital North, Shanghai Jiao Tong University School of Medicine, Shanghai, China; Department of Neurology, Suzhou Hospital Affiliated to Anhui Medical University, Suzhou, China.
| | - Guohua Zhao
- Department of Neurology, The Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China; Department of Neurology, The Fourth Affiliated Hospital, Zhejiang University School of Medicine, Yiwu, China.
| | - Qing Liu
- Department of Neurology, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China.
| | - Ping Zhong
- Department of Neurology, Suzhou Hospital Affiliated to Anhui Medical University, Suzhou, China.
| | - Mei Zhang
- Department of Neurology, Huainan First People's Hospital Affiliated to Bengbu Medical College, Huainan, Anhui Province, China.
| | - Weiguo Tang
- Department of Neurology, Zhoushan Hospital, Zhoushan, Zhejiang Province, China.
| | - Feixia Zhan
- Department of Neurology and Institute of Neurology, Rui Jin Hospital & Rui Jin Hospital North, Shanghai Jiao Tong University School of Medicine, Shanghai, China.
| | - Wotu Tian
- Department of Neurology and Institute of Neurology, Rui Jin Hospital & Rui Jin Hospital North, Shanghai Jiao Tong University School of Medicine, Shanghai, China.
| | - Yan Wang
- Department of Neurology and Institute of Neurology, Rui Jin Hospital & Rui Jin Hospital North, Shanghai Jiao Tong University School of Medicine, Shanghai, China; Department of Neurology, Huainan First People's Hospital Affiliated to Bengbu Medical College, Huainan, Anhui Province, China.
| | - Kaili Yin
- McKusick-Zhang Center for Genetic Medicine and State Key Laboratory of Medical Molecular Biology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences (CAMS) & Peking Union Medical College (PUMC), Beijing, China.
| | - Xiaojun Huang
- Department of Neurology and Institute of Neurology, Rui Jin Hospital & Rui Jin Hospital North, Shanghai Jiao Tong University School of Medicine, Shanghai, China.
| | - Jingwen Jiang
- Department of Neurology and Institute of Neurology, Rui Jin Hospital & Rui Jin Hospital North, Shanghai Jiao Tong University School of Medicine, Shanghai, China.
| | - Xiaoli Liu
- Department of Neurology and Institute of Neurology, Rui Jin Hospital & Rui Jin Hospital North, Shanghai Jiao Tong University School of Medicine, Shanghai, China; Department of Neurology, Shanghai Fengxian District Central Hospital, Shanghai Jiao Tong University Affiliated Sixth People's Hospital South Campus, Shangha, China.
| | - Shihua Liu
- Department of Neurology, Suzhou Hospital Affiliated to Anhui Medical University, Suzhou, China.
| | - Haiyan Zhou
- Department of Neurology and Institute of Neurology, Rui Jin Hospital & Rui Jin Hospital North, Shanghai Jiao Tong University School of Medicine, Shanghai, China.
| | - Xinghua Luan
- Department of Neurology and Institute of Neurology, Rui Jin Hospital & Rui Jin Hospital North, Shanghai Jiao Tong University School of Medicine, Shanghai, China.
| | - Huidong Tang
- Department of Neurology and Institute of Neurology, Rui Jin Hospital & Rui Jin Hospital North, Shanghai Jiao Tong University School of Medicine, Shanghai, China.
| | - Ying Wang
- Department of Neurology and Institute of Neurology, Rui Jin Hospital & Rui Jin Hospital North, Shanghai Jiao Tong University School of Medicine, Shanghai, China.
| | - Shengdi Chen
- Department of Neurology and Institute of Neurology, Rui Jin Hospital & Rui Jin Hospital North, Shanghai Jiao Tong University School of Medicine, Shanghai, China.
| | - Li Cao
- Department of Neurology and Institute of Neurology, Rui Jin Hospital & Rui Jin Hospital North, Shanghai Jiao Tong University School of Medicine, Shanghai, China.
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Jeong B, Kim TH, Kim DS, Shin WH, Lee JR, Kim NS, Lee DY. Spastin Contributes to Neural Development through the Regulation of Microtubule Dynamics in the Primary Cilia of Neural Stem Cells. Neuroscience 2019; 411:76-85. [PMID: 31150727 DOI: 10.1016/j.neuroscience.2019.05.024] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2019] [Revised: 04/25/2019] [Accepted: 05/12/2019] [Indexed: 11/15/2022]
Abstract
Spastin is a microtubule-severing enzyme encoded by SPAST, which is broadly expressed in various cell types originated from multiple organs. Even though SPAST is well known as a regulator of the axon growth and arborization in neurons and a genetic factor of hereditary spastic paraplegia, it also takes part in a wide range of other cellular functions including the regulation of cell division and proliferation. In this study, we investigated a novel biological role of spastin in developing brain using Spast deficient mouse embryonic neural stem cells (NSCs) and perinatal mouse brain. We found that the expression of spastin begins at early embryonic stages in mouse brain. Using Spast shRNA treated NSCs and mouse brain, we showed that Spast deficiency leads to decrease of NSC proliferation and neuronal lineage differentiation. Finally, we found that spastin controls NSC proliferation by regulating microtubule dynamics in primary cilia. Collectively, these data demonstrate that spastin controls brain development by the regulation of NSC functions at early developmental stages.
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Affiliation(s)
- Bohyeon Jeong
- Rare Disease Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), 125 Gwahak-ro, Yuseong-gu, Daejeon 34141, South Korea; Department of Functional Genomics, KRIBB School of Bioscience, Korea University of Science and Technology, Daejeon, South Korea
| | - Tae Hwan Kim
- Rare Disease Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), 125 Gwahak-ro, Yuseong-gu, Daejeon 34141, South Korea
| | - Dae-Soo Kim
- Environmental Disease Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), 125 Gwahak-ro, Yuseong-gu, Daejeon 34141, South Korea; Department of Bioinformatics, KRIBB School of Bioscience, Korea University of Science and Technology, Daejeon, South Korea
| | - Won-Ho Shin
- Department of Predictive Toxicology, Korea Institute of Toxicology, Daejeon 34114, South Korea
| | - Jae-Ran Lee
- Rare Disease Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), 125 Gwahak-ro, Yuseong-gu, Daejeon 34141, South Korea; Department of Biomolecular Science, KRIBB School of Bioscience, Korea University of Science and Technology, Daejeon, South Korea
| | - Nam-Soon Kim
- Rare Disease Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), 125 Gwahak-ro, Yuseong-gu, Daejeon 34141, South Korea; Department of Functional Genomics, KRIBB School of Bioscience, Korea University of Science and Technology, Daejeon, South Korea
| | - Da Yong Lee
- Rare Disease Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), 125 Gwahak-ro, Yuseong-gu, Daejeon 34141, South Korea; Department of Functional Genomics, KRIBB School of Bioscience, Korea University of Science and Technology, Daejeon, South Korea.
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Kelle D, Kırımtay K, Selçuk E, Karabay A. Elk1 affects katanin and spastin proteins via differential transcriptional and post-transcriptional regulations. PLoS One 2019; 14:e0212518. [PMID: 30789974 PMCID: PMC6383945 DOI: 10.1371/journal.pone.0212518] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2018] [Accepted: 02/04/2019] [Indexed: 01/06/2023] Open
Abstract
Microtubule severing, which is highly critical for the survival of both mitotic and post-mitotic cells, has to be precisely adjusted by regulating the expression levels of severing proteins, katanin and spastin. Even though severing mechanism is relatively well-studied, there are limited studies for the transcriptional regulation of microtubule severing proteins. In this study, we identified the main regulatory region of KATNA1 gene encoding katanin-p60 as 5’ UTR, which has a key role for its expression, and showed Elk1 binding to KATNA1. Furthermore, we identified that Elk1 decreased katanin-p60 and spastin protein expressions, while mRNA levels were increased upon Elk1 overexpression. In addition, SUMOylation is a known post-translational modification regulating Elk1 activity. A previous study suggested that K230, K249, K254 amino acids in the R domain are the main SUMOylation sites; however, we identified that these amino acids are neither essential nor substantial for Elk1 SUMOylation. Also, we determined that KATNA1 methylation results in the reduction of Elk1 binding whereas SPG4 methylation does not. Together, our findings emphasizing the impacts of both transcriptional and post-transcriptional regulations of katanin-p60 and spastin suggest that Elk1 has a key role for differential expression patterns of microtubule severing proteins, thereby regulating cellular functions through alterations of microtubule organization.
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Affiliation(s)
- Dolunay Kelle
- Department of Molecular Biology and Genetics, Istanbul Technical University, Maslak, Istanbul, Turkey
| | - Koray Kırımtay
- Department of Molecular Biology and Genetics, Istanbul Technical University, Maslak, Istanbul, Turkey
| | - Ece Selçuk
- Department of Molecular Biology and Genetics, Istanbul Technical University, Maslak, Istanbul, Turkey
| | - Arzu Karabay
- Department of Molecular Biology and Genetics, Istanbul Technical University, Maslak, Istanbul, Turkey
- * E-mail:
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Goliand I, Adar-Levor S, Segal I, Nachmias D, Dadosh T, Kozlov MM, Elia N. Resolving ESCRT-III Spirals at the Intercellular Bridge of Dividing Cells Using 3D STORM. Cell Rep 2018; 24:1756-1764. [PMID: 30110633 DOI: 10.1016/j.celrep.2018.07.051] [Citation(s) in RCA: 46] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2017] [Revised: 04/10/2018] [Accepted: 07/16/2018] [Indexed: 11/26/2022] Open
Abstract
The ESCRT machinery mediates membrane fission in a variety of processes in cells. According to current models, ESCRT-III proteins drive membrane fission by assembling into helical filaments on membranes. Here, we used 3D STORM imaging of endogenous ESCRT-III component IST1 to reveal the evolution of the structural organization of ESCRT-III in mammalian cytokinetic abscission. Using this approach, ESCRT-III ring and spiral assemblies were resolved and characterized at different stages of abscission. Visualization of IST1 structures in cells lacking the microtubule-severing enzyme spastin and in cells depleted of specific ESCRT-III components or the ATPase VPS4 demonstrated the contribution of these components to the organization and function of ESCRTs in cells. This work provides direct evidence that ESCRT-III proteins form helical filaments to mediate their function in cells and raises new mechanistic scenarios for ESCRT-driven cytokinetic abscission.
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Affiliation(s)
- Inna Goliand
- Department of Life Sciences and NIBN, Ben-Gurion University of the Negev, Beer Sheva 84105, Israel
| | - Shai Adar-Levor
- Department of Life Sciences and NIBN, Ben-Gurion University of the Negev, Beer Sheva 84105, Israel
| | - Inbar Segal
- Department of Life Sciences and NIBN, Ben-Gurion University of the Negev, Beer Sheva 84105, Israel
| | - Dikla Nachmias
- Department of Life Sciences and NIBN, Ben-Gurion University of the Negev, Beer Sheva 84105, Israel
| | - Tali Dadosh
- Department of Chemical Research Support, Faculty of Chemistry, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Michael M Kozlov
- Department of Physiology and Pharmacology, Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv 69978, Israel
| | - Natalie Elia
- Department of Life Sciences and NIBN, Ben-Gurion University of the Negev, Beer Sheva 84105, Israel.
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Lu C, Li LX, Dong HL, Wei Q, Liu ZJ, Ni W, Gitler AD, Wu ZY. Targeted next-generation sequencing improves diagnosis of hereditary spastic paraplegia in Chinese patients. J Mol Med (Berl) 2018; 96:701-712. [PMID: 29934652 DOI: 10.1007/s00109-018-1655-4] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2017] [Revised: 05/01/2018] [Accepted: 05/07/2018] [Indexed: 12/30/2022]
Abstract
Hereditary spastic paraplegia (HSP) is a heterogeneous group of neurodegenerative diseases characterized by progressive weakness and spasticity of lower limbs. To clarify the genetic spectrum and improve the diagnosis of HSP patients, targeted next-generation sequencing (NGS) was applied to detect the culprit genes in 55 Chinese HSP pedigrees. The classification of novel variants was based on the American College of Medical Genetics and Genomics (ACMG) standards and guidelines. Patients remaining negative following targeted NGS were further screened for gross deletions/duplications by multiplex ligation-dependent probe amplification (MLPA). We made a genetic diagnosis in 61.8% (34/55) of families and identified 33 mutations, including 14 known mutations and 19 novel mutations. Of them, one was de novo mutation (NIPA1: c.316G>A). SPAST mutations (22/39, 56.4%) are the most common in Chinese AD-HSP followed by ATL1 (4/39, 10.3%). Moreover, we identified the third BSCL2 mutation (c.1309G>C) related to HSP by further functional studies and first reported the KIF1A mutation (c.304G>A) in China. Our findings broaden the genetic spectrum of HSP and improve the diagnosis of HSP patients. These results demonstrate the efficiency of targeted NGS to make a more rapid and precise diagnosis in patients with clinically suspected HSP. KEY MESSAGES We made a genetic diagnosis in 61.8% of families and identified 33 mutations. SPAST mutations are the most common in Chinese AD-HSP followed by ATL1. Our findings broaden the genetic spectrum and improve the diagnosis of HSP.
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Affiliation(s)
- Cong Lu
- Department of Neurology and Research Center of Neurology in Second Affiliated Hospital, and Key Laboratory of Medical Neurobiology of Zhejiang Province, Zhejiang University School of Medicine, 88 Jiefang Road, Hangzhou, 310009, China
- Department of Neurology and Institute of Neurology, First Affiliated Hospital, Fujian Medical University, Fuzhou, China
| | - Li-Xi Li
- Department of Neurology and Research Center of Neurology in Second Affiliated Hospital, and Key Laboratory of Medical Neurobiology of Zhejiang Province, Zhejiang University School of Medicine, 88 Jiefang Road, Hangzhou, 310009, China
| | - Hai-Lin Dong
- Department of Neurology and Research Center of Neurology in Second Affiliated Hospital, and Key Laboratory of Medical Neurobiology of Zhejiang Province, Zhejiang University School of Medicine, 88 Jiefang Road, Hangzhou, 310009, China
| | - Qiao Wei
- Department of Neurology and Research Center of Neurology in Second Affiliated Hospital, and Key Laboratory of Medical Neurobiology of Zhejiang Province, Zhejiang University School of Medicine, 88 Jiefang Road, Hangzhou, 310009, China
| | - Zhi-Jun Liu
- Department of Neurology and Institute of Neurology, Huashan Hospital, Shanghai Medical College, Fudan University, Shanghai, China
| | - Wang Ni
- Department of Neurology and Research Center of Neurology in Second Affiliated Hospital, and Key Laboratory of Medical Neurobiology of Zhejiang Province, Zhejiang University School of Medicine, 88 Jiefang Road, Hangzhou, 310009, China
| | - Aaron D Gitler
- Department of Genetics, Stanford University School of Medicine, Stanford, USA
| | - Zhi-Ying Wu
- Department of Neurology and Research Center of Neurology in Second Affiliated Hospital, and Key Laboratory of Medical Neurobiology of Zhejiang Province, Zhejiang University School of Medicine, 88 Jiefang Road, Hangzhou, 310009, China.
- Joint Institute for Genetics and Genome Medicine Between Zhejiang University and University of Toronto, Zhejiang University, Hangzhou, China.
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27
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Abstract
Hereditary spastic paraplegia is a phenotypically and genetically heterogeneous group of neurodegenerative disorders characterized by lower extremity weakness and spasticity. Spastic paraplegia 4 (SPG4), caused by heterozygous mutations in the gene SPAST, typically causes a late-onset, uncomplicated form of hereditary spastic paraplegia in affected individuals. Additional clinical features in SPG4 have been reported on occasion, but no genotype-phenotype correlation has been established. Through targeted clinical testing, we identified 2 unrelated female patients with the same de novo p.Arg499His mutation in SPAST. Both patients presented with early-onset spasticity resulting in delayed motor milestones, which led to a diagnosis of cerebral palsy in one child and tethered cord in the other. Review of the literature identified several patients with mutations at amino acid 499 and early-onset symptoms associated with a risk of cognitive impairment. Early and accurate diagnosis of children with early-onset spasticity is important for informed prognosis and genetic counselling.
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Affiliation(s)
- Meredith K Gillespie
- 1 Children's Hospital of Eastern Ontario Research Institute, University of Ottawa, Ottawa, ON, Canada
| | - Peter Humphreys
- 1 Children's Hospital of Eastern Ontario Research Institute, University of Ottawa, Ottawa, ON, Canada
- 2 Division of Neurology, Department of Pediatrics, Children's Hospital of Eastern Ontario, Ottawa, ON, Canada
| | - Hugh J McMillan
- 1 Children's Hospital of Eastern Ontario Research Institute, University of Ottawa, Ottawa, ON, Canada
- 2 Division of Neurology, Department of Pediatrics, Children's Hospital of Eastern Ontario, Ottawa, ON, Canada
| | - Kym M Boycott
- 1 Children's Hospital of Eastern Ontario Research Institute, University of Ottawa, Ottawa, ON, Canada
- 3 Department of Genetics, Children's Hospital of Eastern Ontario, Ottawa, ON, Canada
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28
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Travaglini L, Bellacchio E, Aiello C, Pro S, Bertini E, Nicita F. Expanding the clinical phenotype of CAPN1-associated mutations: A new case with congenital-onset pure spastic paraplegia. J Neurol Sci 2017; 378:210-212. [PMID: 28566166 DOI: 10.1016/j.jns.2017.05.014] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2017] [Revised: 04/07/2017] [Accepted: 05/09/2017] [Indexed: 11/19/2022]
Affiliation(s)
- Lorena Travaglini
- Department of Neurosciences, Unit of Neuromuscular and Neurodegenerative Disorders, Laboratory of Molecular Medicine, Bambino Gesù Children's Hospital, IRCCS, Rome, Italy.
| | | | - Chiara Aiello
- Department of Neurosciences, Unit of Neuromuscular and Neurodegenerative Disorders, Laboratory of Molecular Medicine, Bambino Gesù Children's Hospital, IRCCS, Rome, Italy
| | - Stefano Pro
- Department of Neurosciences, Unit of Neurology, Bambino Gesù Children's Hospital, IRCCS, Rome, Italy
| | - Enrico Bertini
- Department of Neurosciences, Unit of Neuromuscular and Neurodegenerative Disorders, Laboratory of Molecular Medicine, Bambino Gesù Children's Hospital, IRCCS, Rome, Italy
| | - Francesco Nicita
- Department of Neurosciences, Unit of Neuromuscular and Neurodegenerative Disorders, Laboratory of Molecular Medicine, Bambino Gesù Children's Hospital, IRCCS, Rome, Italy
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29
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Hauser S, Erzler M, Theurer Y, Schuster S, Schüle R, Schöls L. Establishment of SPAST mutant induced pluripotent stem cells (iPSCs) from a hereditary spastic paraplegia (HSP) patient. Stem Cell Res 2016; 17:485-488. [PMID: 27789400 DOI: 10.1016/j.scr.2016.09.022] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/12/2016] [Accepted: 09/22/2016] [Indexed: 11/16/2022] Open
Abstract
Human skin fibroblasts were isolated from a 40-year-old hereditary spastic paraplegia patient carrying an intronic splice site mutation (c.1687+2T>A) in SPAST, leading to hereditary spastic paraplegia type 4 (SPG4). Fibroblasts were reprogrammed using episomal plasmids carrying hOCT4, hSOX2, hKLF4, hL-MYC and hLIN28. The generated transgene-free line iPS-SPG4-splice retained the specific mutation with no additional genomic aberrations, expressed pluripotency markers and was able to differentiate into cells of all germ layers in vitro. The generated iPS-SPG4-splice line might be a useful platform to study the pathomechanism of SPG4.
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Affiliation(s)
- Stefan Hauser
- German Center for Neurodegenerative Diseases (DZNE), Tuebingen, Germany
| | - Melanie Erzler
- German Center for Neurodegenerative Diseases (DZNE), Tuebingen, Germany
| | - Yvonne Theurer
- German Center for Neurodegenerative Diseases (DZNE), Tuebingen, Germany
| | - Stefanie Schuster
- Department of Neurology and Hertie Institute for Clinical Brain Research, University of Tuebingen, Tuebingen, Germany; Graduate School of Cellular and Molecular Neuroscience, University of Tuebingen, Tuebingen, Germany
| | - Rebecca Schüle
- German Center for Neurodegenerative Diseases (DZNE), Tuebingen, Germany; Department of Neurology and Hertie Institute for Clinical Brain Research, University of Tuebingen, Tuebingen, Germany
| | - Ludger Schöls
- German Center for Neurodegenerative Diseases (DZNE), Tuebingen, Germany; Department of Neurology and Hertie Institute for Clinical Brain Research, University of Tuebingen, Tuebingen, Germany.
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30
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Akhmetgaleyeva AF, Khidiyatova IM, Saifullina EV, Idrisova RF, Magzhanov RV, Khusnutdinova EK. [Two novel mutations in gene SPG4 in patients with autosomal dominant spastic paraplegia]. Genetika 2016; 52:691-696. [PMID: 29368828] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Hereditary spastik paraplegias (HSP) are a group of neurodegenerative disorders with primary lesion of the pyramidal tract. The most frequent autosomal dominant form of the disease in Europeans is HSP associated with mutations in the spastin gene (SPG4). Analysis of the gene SPG4 was carried out in 52 unrelated families with HSP from Bashkortostan by SSCP and following sequencing. Previously undescribed frameshift mutations c.322del29 (p.Val108SerfsX18) and c.885del10 (p.Thr295ThrfsX16) were detected in two unrelated families. Clinical studies have shown that, in both families, the disease corresponds to an uncomplicated form of hereditary spastic paraplegia, a main feature of which is the lower spastic paraparesis without any other symptoms.
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