3
|
Liu L, Su R, Huang P, Li X, Xiong J, Xiao Y, Mao D, Liu L. Case Report: Evidences of myasthenia and cerebellar atrophy in a chinese patient with novel compound heterozygous MSTO1 variants. Front Genet 2022; 13:947886. [PMID: 36035138 PMCID: PMC9402982 DOI: 10.3389/fgene.2022.947886] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2022] [Accepted: 07/05/2022] [Indexed: 11/29/2022] Open
Abstract
Misato Mitochondrial Distribution and Morphology Regulator 1 (MSTO1) is a soluble cytoplasmic protein that regulates mitochondrial dynamics by promoting mitochondrial fusion. Variants in the MSTO1 gene cause a rare disease characterized by early-onset myopathy and cerebellar ataxia, with almost 30 cases reported worldwide. Here we report a case of a 3-year-old boy with novel heterozygous variants of the MSTO1 gene (c.1A>G (p.M1?) and c.727G>C(p.Ala243Pro)). Sequencing data and subsequent validation show that the two variants were inherited from the mother and father of the patient (both were heterozygous). The clinical features are infancy-onset mental and motor retardation, language disorder, dysarthria, scoliosis, cerebellar atrophy, tremor, lower-extremity muscle weakness, elevated muscle enzymes, extensive myopathy with chronic atrophy, hyperventilation lungs, and previously unreported hairy back and enlarged gastrocnemius. Finally, novel heterozygous MSTO1 variants were discovered in this case, which expands the gene spectrum and clinical phenotype of this type of disease, and provides a new direction for future treatment and research. Then we summarize the mutational spectrum, pathological, clinical features and imaging of MSTO1 variants in a cohort of reported 31 patients and discuss the pathogenesis of MSTO1 in humans.
Collapse
Affiliation(s)
- Liqun Liu
- Department of Pediatrics, The Second Xiangya Hospital of Central South University, Changsha, China
- Department of Pediatric Neurology, Patientren’s Medical Center, Xiangya Hospital of Central South University, Changsha, China
| | - Ruiting Su
- Department of Clinical Medicine, Xiangya Medical College, Central South University, Changsha, China
| | - Peng Huang
- Department of Pediatrics, The Second Xiangya Hospital of Central South University, Changsha, China
- Department of Pediatric Neurology, Patientren’s Medical Center, Xiangya Hospital of Central South University, Changsha, China
| | - Xingfang Li
- Department of Pediatrics, The Second Xiangya Hospital of Central South University, Changsha, China
- Department of Pediatric Neurology, Patientren’s Medical Center, Xiangya Hospital of Central South University, Changsha, China
| | - Jie Xiong
- Department of Pediatrics, The Second Xiangya Hospital of Central South University, Changsha, China
- Department of Pediatric Neurology, Patientren’s Medical Center, Xiangya Hospital of Central South University, Changsha, China
| | - Yangyang Xiao
- Department of Pediatrics, The Second Xiangya Hospital of Central South University, Changsha, China
- Department of Pediatric Neurology, Patientren’s Medical Center, Xiangya Hospital of Central South University, Changsha, China
| | - Dingan Mao
- Department of Pediatrics, The Second Xiangya Hospital of Central South University, Changsha, China
- Department of Pediatric Neurology, Patientren’s Medical Center, Xiangya Hospital of Central South University, Changsha, China
| | - Lingjuan Liu
- Department of Pediatrics, The Second Xiangya Hospital of Central South University, Changsha, China
- Department of Pediatric Neurology, Patientren’s Medical Center, Xiangya Hospital of Central South University, Changsha, China
- *Correspondence: Lingjuan Liu,
| |
Collapse
|
5
|
Nasca A, Di Meo I, Fellig Y, Saada A, Elpeleg O, Ghezzi D, Edvardson S. A novel homozygous MSTO1 mutation in Ashkenazi Jewish siblings with ataxia and myopathy. J Hum Genet 2021; 66:835-840. [PMID: 33612823 DOI: 10.1038/s10038-020-00897-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2020] [Revised: 11/16/2020] [Accepted: 11/16/2020] [Indexed: 11/09/2022]
Abstract
MSTO1 is a cytoplasmic protein that modulates mitochondrial dynamics by promoting mitochondrial fusion. Mutations in the MSTO1 gene are responsible for an extremely rare condition characterized by early-onset myopathy and cerebellar ataxia. We report here two siblings from a large Ashkenazi Jewish family, presenting with a progressive neuromuscular disease characterized by ataxia and myopathy. By whole exome sequencing, we found a novel homozygous missense mutation (c.1403T>A, p.Leu468Gln) in MSTO1. Studies performed on fibroblasts from the index patient demonstrated the pathogenic role of the identified variant; we found that MSTO1 protein level was reduced and that mitochondrial network was fragmented or formed enlarged structures. Moreover, patient's cells showed reduced mitochondrial DNA amount. Our report confirms that MSTO1 mutations are typically recessive, and associated with clinical phenotypes characterized by early-onset muscle impairment and ataxia, often with upper motor neuron signs and varied cognitive impairment.
Collapse
Affiliation(s)
- Alessia Nasca
- Unit of Medical Genetics and Neurogenetics, Fondazione IRCCS Istituto Neurologico Carlo Besta, 20126, Milan, Italy
| | - Ivano Di Meo
- Unit of Medical Genetics and Neurogenetics, Fondazione IRCCS Istituto Neurologico Carlo Besta, 20126, Milan, Italy
| | - Yakov Fellig
- Department of Pathology, Hadassah Hebrew University of Jerusalem, 91120, Jerusalem, Israel
| | - Ann Saada
- Department of Genetics, Hadassah Hebrew University of Jerusalem, 91120, Jerusalem, Israel
| | - Orly Elpeleg
- Department of Genetics, Hadassah Hebrew University of Jerusalem, 91120, Jerusalem, Israel
| | - Daniele Ghezzi
- Unit of Medical Genetics and Neurogenetics, Fondazione IRCCS Istituto Neurologico Carlo Besta, 20126, Milan, Italy. .,Department of Pathophysiology and Transplantation, University of Milan, 20122, Milan, Italy.
| | - Shimon Edvardson
- Pediatric Neurology Unit, Hadassah Hebrew University of Jerusalem, 91240, Jerusalem, Israel.
| |
Collapse
|
7
|
Donkervoort S, Sabouny R, Yun P, Gauquelin L, Chao KR, Hu Y, Al Khatib I, Töpf A, Mohassel P, Cummings BB, Kaur R, Saade D, Moore SA, Waddell LB, Farrar MA, Goodrich JK, Uapinyoying P, Chan SHS, Javed A, Leach ME, Karachunski P, Dalton J, Medne L, Harper A, Thompson C, Thiffault I, Specht S, Lamont RE, Saunders C, Racher H, Bernier FP, Mowat D, Witting N, Vissing J, Hanson R, Coffman KA, Hainlen M, Parboosingh JS, Carnevale A, Yoon G, Schnur RE, Boycott KM, Mah JK, Straub V, Foley AR, Innes AM, Bönnemann CG, Shutt TE. MSTO1 mutations cause mtDNA depletion, manifesting as muscular dystrophy with cerebellar involvement. Acta Neuropathol 2019; 138:1013-1031. [PMID: 31463572 PMCID: PMC6851037 DOI: 10.1007/s00401-019-02059-z] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2019] [Revised: 07/25/2019] [Accepted: 08/08/2019] [Indexed: 01/12/2023]
Abstract
MSTO1 encodes a cytosolic mitochondrial fusion protein, misato homolog 1 or MSTO1. While the full genotype-phenotype spectrum remains to be explored, pathogenic variants in MSTO1 have recently been reported in a small number of patients presenting with a phenotype of cerebellar ataxia, congenital muscle involvement with histologic findings ranging from myopathic to dystrophic and pigmentary retinopathy. The proposed underlying pathogenic mechanism of MSTO1-related disease is suggestive of impaired mitochondrial fusion secondary to a loss of function of MSTO1. Disorders of mitochondrial fusion and fission have been shown to also lead to mitochondrial DNA (mtDNA) depletion, linking them to the mtDNA depletion syndromes, a clinically and genetically diverse class of mitochondrial diseases characterized by a reduction of cellular mtDNA content. However, the consequences of pathogenic variants in MSTO1 on mtDNA maintenance remain poorly understood. We present extensive phenotypic and genetic data from 12 independent families, including 15 new patients harbouring a broad array of bi-allelic MSTO1 pathogenic variants, and we provide functional characterization from seven MSTO1-related disease patient fibroblasts. Bi-allelic loss-of-function variants in MSTO1 manifest clinically with a remarkably consistent phenotype of childhood-onset muscular dystrophy, corticospinal tract dysfunction and early-onset non-progressive cerebellar atrophy. MSTO1 protein was not detectable in the cultured fibroblasts of all seven patients evaluated, suggesting that pathogenic variants result in a loss of protein expression and/or affect protein stability. Consistent with impaired mitochondrial fusion, mitochondrial networks in fibroblasts were found to be fragmented. Furthermore, all fibroblasts were found to have depletion of mtDNA ranging from 30 to 70% along with alterations to mtDNA nucleoids. Our data corroborate the role of MSTO1 as a mitochondrial fusion protein and highlight a previously unrecognized link to mtDNA regulation. As impaired mitochondrial fusion is a recognized cause of mtDNA depletion syndromes, this novel link to mtDNA depletion in patient fibroblasts suggests that MSTO1-deficiency should also be considered a mtDNA depletion syndrome. Thus, we provide mechanistic insight into the disease pathogenesis associated with MSTO1 mutations and further define the clinical spectrum and the natural history of MSTO1-related disease.
Collapse
Affiliation(s)
- S Donkervoort
- Neuromuscular and Neurogenetic Disorders of Childhood Section, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, USA
| | - R Sabouny
- Department of Biochemistry and Molecular Biology, University of Calgary, Calgary, Canada
| | - P Yun
- Neuromuscular and Neurogenetic Disorders of Childhood Section, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, USA
| | - L Gauquelin
- Division of Clinical and Metabolic Genetics, Department of Paediatrics, The Hospital for Sick Children, University of Toronto, Toronto, ON, Canada
- Division of Neurology, Department of Paediatrics, The Hospital for Sick Children, University of Toronto, Toronto, ON, Canada
| | - K R Chao
- Center for Mendelian Genomics, Program in Medical and Population Genetics, Broad Institute of MIT and Harvard, Boston, MA, USA
| | - Y Hu
- Neuromuscular and Neurogenetic Disorders of Childhood Section, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, USA
| | - I Al Khatib
- Department of Biochemistry and Molecular Biology, University of Calgary, Calgary, Canada
| | - A Töpf
- John Walton Muscular Dystrophy Research Centre, Institute of Genetic Medicine, Newcastle University, Newcastle upon Tyne, UK
| | - P Mohassel
- Neuromuscular and Neurogenetic Disorders of Childhood Section, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, USA
| | - B B Cummings
- Center for Mendelian Genomics, Program in Medical and Population Genetics, Broad Institute of MIT and Harvard, Boston, MA, USA
| | - R Kaur
- Neuromuscular and Neurogenetic Disorders of Childhood Section, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, USA
| | - D Saade
- Neuromuscular and Neurogenetic Disorders of Childhood Section, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, USA
| | - S A Moore
- Department of Pathology Carver College of Medicine, The University of Iowa, Iowa City, IA, USA
| | - L B Waddell
- Kids Neuroscience Centre, Kids Research, The Children's Hospital at Westmead, Sydney, NSW 2145, Australia
- Discipline of Child and Adolescent Health, Faculty of Medicine and Health, The University of Sydney, Westmead, NSW 2145, Australia
| | - M A Farrar
- Department of Neurology, Sydney Children's Hospital, Sydney, NSW, Australia
- UNSW Sydney, School of Women's and Children's Health, Sydney, NSW, Australia
| | - J K Goodrich
- Center for Mendelian Genomics, Program in Medical and Population Genetics, Broad Institute of MIT and Harvard, Boston, MA, USA
| | - P Uapinyoying
- Neuromuscular and Neurogenetic Disorders of Childhood Section, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, USA
- Research for Genetic Medicine, Children's National Medical Center, Washington, DC, USA
| | - S H S Chan
- Department of Paediatrics and Adolescent Medicine, Queen Mary Hospital, The University of Hong Kong, Hong Kong SAR, China
| | - A Javed
- School of Biomedical Science, The University of Hong Kong, Hong Kong SAR, China
| | - M E Leach
- Neuromuscular and Neurogenetic Disorders of Childhood Section, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, USA
- Oregon Health and Science University, Neuromuscular Program, Doernbecher Children's Hospital, Portland, OR, USA
| | - P Karachunski
- Department of Neurology, University of Minnesota, Minneapolis, MN, USA
| | - J Dalton
- Department of Neurology, University of Minnesota, Minneapolis, MN, USA
| | - L Medne
- Division of Human Genetics, The Children's Hospital of Philadelphia, Philadelphia, USA
| | - A Harper
- Department of Neurology, Virginia Commonwealth University, Children's Hospital of Richmond at VCU, Richmond, VA, USA
| | - C Thompson
- Department of Pediatrics, University of California San Diego, San Diego, CA, USA
| | - I Thiffault
- Department of Pathology and Laboratory Medicine, Children's Mercy Hospital, Kansas City, USA
- Center for Pediatric Genomic Medicine, Children's Mercy Hospital, Kansas City, USA
- University of Missouri-Kansas City School of Medicine, Kansas City, USA
| | - S Specht
- John Walton Muscular Dystrophy Research Centre, Institute of Genetic Medicine, Newcastle University, Newcastle upon Tyne, UK
| | - R E Lamont
- Department of Medical Genetics and Alberta Children's Hospital Research Institute, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
| | - C Saunders
- Department of Pathology and Laboratory Medicine, Children's Mercy Hospital, Kansas City, USA
- Center for Pediatric Genomic Medicine, Children's Mercy Hospital, Kansas City, USA
- University of Missouri-Kansas City School of Medicine, Kansas City, USA
| | - H Racher
- Department of Medical Genetics and Alberta Children's Hospital Research Institute, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
| | - F P Bernier
- Department of Medical Genetics and Alberta Children's Hospital Research Institute, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
| | - D Mowat
- UNSW Sydney, School of Women's and Children's Health, Sydney, NSW, Australia
- Department of Medical Genetics, Sydney Children's Hospital, Sydney, NSW, Australia
| | - N Witting
- Department of Neurology, University Hospital Rigshospitalet, Copenhagen, Denmark
| | - J Vissing
- Department of Neurology, University Hospital Rigshospitalet, Copenhagen, Denmark
| | - R Hanson
- University of Missouri-Kansas City School of Medicine, Kansas City, USA
- Department of Pediatrics, Children's Mercy Hospital, Kansas City, USA
| | - K A Coffman
- Department of Pediatrics, Children's Mercy Hospital, Kansas City, USA
- Division of Neurology, Children's Mercy Hospital, Kansas City, USA
| | - M Hainlen
- Department of Pediatrics, Children's Mercy Hospital, Kansas City, USA
- Division of Neurology, Children's Mercy Hospital, Kansas City, USA
| | - J S Parboosingh
- Department of Medical Genetics and Alberta Children's Hospital Research Institute, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
| | - A Carnevale
- Division of Clinical and Metabolic Genetics, Department of Paediatrics, The Hospital for Sick Children, University of Toronto, Toronto, ON, Canada
| | - G Yoon
- Division of Clinical and Metabolic Genetics, Department of Paediatrics, The Hospital for Sick Children, University of Toronto, Toronto, ON, Canada
- Division of Neurology, Department of Paediatrics, The Hospital for Sick Children, University of Toronto, Toronto, ON, Canada
| | | | - K M Boycott
- Children's Hospital of Eastern Ontario Research Institute, University of Ottawa, Ottawa, Canada
- Care4Rare Research Consortium, Ottawa, Canada
| | - J K Mah
- Departments of Pediatrics, Section of Neurology, University of Calgary, Calgary, AB, Canada
| | - V Straub
- John Walton Muscular Dystrophy Research Centre, Institute of Genetic Medicine, Newcastle University, Newcastle upon Tyne, UK
- Newcastle Hospitals NHS Foundation Trust, Newcastle upon Tyne, UK
| | - A Reghan Foley
- Neuromuscular and Neurogenetic Disorders of Childhood Section, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, USA
| | - A M Innes
- Department of Medical Genetics and Alberta Children's Hospital Research Institute, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
| | - C G Bönnemann
- Neuromuscular and Neurogenetic Disorders of Childhood Section, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, USA.
| | - T E Shutt
- Department of Biochemistry and Molecular Biology, University of Calgary, Calgary, Canada.
- Department of Medical Genetics, Alberta Children's Hospital Research Institute, Hotchkiss Brain Institute, University of Calgary, Calgary, Canada.
| |
Collapse
|