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Traverso M, Baratto S, Iacomino M, Di Duca M, Panicucci C, Casalini S, Grandis M, Falace A, Torella A, Picillo E, Onore ME, Politano L, Nigro V, Innes AM, Barresi R, Bruno C, Zara F, Fiorillo C, Scala M. DAG1 haploinsufficiency is associated with sporadic and familial isolated or pauci-symptomatic hyperCKemia. Eur J Hum Genet 2024; 32:342-349. [PMID: 38177406 PMCID: PMC10923780 DOI: 10.1038/s41431-023-01516-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2023] [Revised: 10/31/2023] [Accepted: 11/27/2023] [Indexed: 01/06/2024] Open
Abstract
DAG1 encodes for dystroglycan, a key component of the dystrophin-glycoprotein complex (DGC) with a pivotal role in skeletal muscle function and maintenance. Biallelic loss-of-function DAG1 variants cause severe muscular dystrophy and muscle-eye-brain disease. A possible contribution of DAG1 deficiency to milder muscular phenotypes has been suggested. We investigated the genetic background of twelve subjects with persistent mild-to-severe hyperCKemia to dissect the role of DAG1 in this condition. Genetic testing was performed through exome sequencing (ES) or custom NGS panels including various genes involved in a spectrum of muscular disorders. Histopathological and Western blot analyses were performed on muscle biopsy samples obtained from three patients. We identified seven novel heterozygous truncating variants in DAG1 segregating with isolated or pauci-symptomatic hyperCKemia in all families. The variants were rare and predicted to lead to nonsense-mediated mRNA decay or the formation of a truncated transcript. In four cases, DAG1 variants were inherited from similarly affected parents. Histopathological analysis revealed a decreased expression of dystroglycan subunits and Western blot confirmed a significantly reduced expression of beta-dystroglycan in muscle samples. This study supports the pathogenic role of DAG1 haploinsufficiency in isolated or pauci-symptomatic hyperCKemia, with implications for clinical management and genetic counseling.
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Affiliation(s)
- Monica Traverso
- Pediatric Neurology and Muscular Diseases Unit, IRCCS Istituto Giannina Gaslini, Genoa, Italy
| | - Serena Baratto
- Centre of Translational and Experimental Myology, IRCCS Istituto Giannina Gaslini, Genoa, Italy
| | - Michele Iacomino
- Medical Genetics Unit, IRCCS Istituto Giannina Gaslini, Genoa, Italy
| | - Marco Di Duca
- Medical Genetics Unit, IRCCS Istituto Giannina Gaslini, Genoa, Italy
| | - Chiara Panicucci
- Centre of Translational and Experimental Myology, IRCCS Istituto Giannina Gaslini, Genoa, Italy
| | - Sara Casalini
- Centre of Translational and Experimental Myology, IRCCS Istituto Giannina Gaslini, Genoa, Italy
| | | | - Antonio Falace
- Pediatric Neurology and Muscular Diseases Unit, IRCCS Istituto Giannina Gaslini, Genoa, Italy
| | - Annalaura Torella
- Department of Precision Medicine, University "Luigi Vanvitelli", Naples, Italy
- Telethon Institute of Genetics and Medicine (TIGEM), Pozzuoli, Italy
| | - Esther Picillo
- Department of Precision Medicine, University "Luigi Vanvitelli", Naples, Italy
- Telethon Institute of Genetics and Medicine (TIGEM), Pozzuoli, Italy
| | - Maria Elena Onore
- Department of Precision Medicine, University "Luigi Vanvitelli", Naples, Italy
- Telethon Institute of Genetics and Medicine (TIGEM), Pozzuoli, Italy
| | - Luisa Politano
- Department of Precision Medicine, University "Luigi Vanvitelli", Naples, Italy
- Telethon Institute of Genetics and Medicine (TIGEM), Pozzuoli, Italy
| | - Vincenzo Nigro
- Department of Precision Medicine, University "Luigi Vanvitelli", Naples, Italy
- Telethon Institute of Genetics and Medicine (TIGEM), Pozzuoli, Italy
| | - A Micheil Innes
- Department of Medical Genetics and Pediatrics, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
- Alberta Children's Hospital Research Institute, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
| | | | - Claudio Bruno
- Centre of Translational and Experimental Myology, IRCCS Istituto Giannina Gaslini, Genoa, Italy
- Department of Neurosciences, Rehabilitation, Ophthalmology, Genetics, Maternal and Child Health, University of Genoa, Genoa, Italy
| | - Federico Zara
- Medical Genetics Unit, IRCCS Istituto Giannina Gaslini, Genoa, Italy.
- Department of Neurosciences, Rehabilitation, Ophthalmology, Genetics, Maternal and Child Health, University of Genoa, Genoa, Italy.
| | - Chiara Fiorillo
- Department of Neurosciences, Rehabilitation, Ophthalmology, Genetics, Maternal and Child Health, University of Genoa, Genoa, Italy.
- Child Neuropsychiatry Unit, IRCCS Istituto Giannina Gaslini, Genoa, Italy.
| | - Marcello Scala
- Medical Genetics Unit, IRCCS Istituto Giannina Gaslini, Genoa, Italy.
- Department of Neurosciences, Rehabilitation, Ophthalmology, Genetics, Maternal and Child Health, University of Genoa, Genoa, Italy.
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2
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Cook M, Stevenson B, Jacobs LA, Leocadio Victoria D, Cisneros B, Hobbs JK, Stewart CL, Winder SJ. The Role of β-Dystroglycan in Nuclear Dynamics. Cells 2024; 13:431. [PMID: 38474395 DOI: 10.3390/cells13050431] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2023] [Revised: 02/18/2024] [Accepted: 02/19/2024] [Indexed: 03/14/2024] Open
Abstract
Dystroglycan is a ubiquitously expressed heterodimeric cell-surface laminin receptor with roles in cell adhesion, signalling, and membrane stabilisation. More recently, the transmembrane β-subunit of dystroglycan has been shown to localise to both the nuclear envelope and the nucleoplasm. This has led to the hypothesis that dystroglycan may have a structural role at the nuclear envelope analogous to its role at the plasma membrane. The biochemical fraction of myoblast cells clearly supports the presence of dystroglycan in the nucleus. Deletion of the dystroglycan protein by disruption of the DAG1 locus using CRISPR/Cas9 leads to changes in nuclear size but not overall morphology; moreover, the Young's modulus of dystroglycan-deleted nuclei, as determined by atomic force microscopy, is unaltered. Dystroglycan-disrupted myoblasts are also no more susceptible to nuclear stresses including chemical and mechanical, than normal myoblasts. Re-expression of dystroglycan in DAG1-disrupted myoblasts restores nuclear size without affecting other nuclear parameters.
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Affiliation(s)
- Matthew Cook
- School of Biosciences, University of Sheffield, Sheffield S10 2TN, UK
- A*STAR Skin Research Laboratories, Singapore 138648, Singapore
| | - Ben Stevenson
- School of Biosciences, University of Sheffield, Sheffield S10 2TN, UK
| | - Laura A Jacobs
- School of Biosciences, University of Sheffield, Sheffield S10 2TN, UK
| | | | - Bulmaro Cisneros
- Department of Genetics and Molecular Biology, Centro de Investigación y de Estudios Avanzados, Mexico City 07360, Mexico
| | - Jamie K Hobbs
- Department of Physics and Astronomy, University of Sheffield, Sheffield S3 7RH, UK
| | - Colin L Stewart
- A*STAR Skin Research Laboratories, Singapore 138648, Singapore
| | - Steve J Winder
- School of Biosciences, University of Sheffield, Sheffield S10 2TN, UK
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3
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Okuma H, Hord JM, Chandel I, Venzke D, Anderson ME, Walimbe AS, Joseph S, Gastel Z, Hara Y, Saito F, Matsumura K, Campbell KP. N-terminal domain on dystroglycan enables LARGE1 to extend matriglycan on α-dystroglycan and prevents muscular dystrophy. eLife 2023; 12:e82811. [PMID: 36723429 PMCID: PMC9917425 DOI: 10.7554/elife.82811] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2022] [Accepted: 01/31/2023] [Indexed: 02/02/2023] Open
Abstract
Dystroglycan (DG) requires extensive post-translational processing and O-glycosylation to function as a receptor for extracellular matrix (ECM) proteins containing laminin-G (LG) domains. Matriglycan is an elongated polysaccharide of alternating xylose (Xyl) and glucuronic acid (GlcA) that binds with high affinity to ECM proteins with LG domains and is uniquely synthesized on α-dystroglycan (α-DG) by like-acetylglucosaminyltransferase-1 (LARGE1). Defects in the post-translational processing or O-glycosylation of α-DG that result in a shorter form of matriglycan reduce the size of α-DG and decrease laminin binding, leading to various forms of muscular dystrophy. Previously, we demonstrated that protein O-mannose kinase (POMK) is required for LARGE1 to generate full-length matriglycan on α-DG (~150-250 kDa) (Walimbe et al., 2020). Here, we show that LARGE1 can only synthesize a short, non-elongated form of matriglycan in mouse skeletal muscle that lacks the DG N-terminus (α-DGN), resulting in an ~100-125 kDa α-DG. This smaller form of α-DG binds laminin and maintains specific force but does not prevent muscle pathophysiology, including reduced force production after eccentric contractions (ECs) or abnormalities in the neuromuscular junctions. Collectively, our study demonstrates that α-DGN, like POMK, is required for LARGE1 to extend matriglycan to its full mature length on α-DG and thus prevent muscle pathophysiology.
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Affiliation(s)
- Hidehiko Okuma
- Howard Hughes Medical Institute, Senator Paul D. Wellstone Muscular Dystrophy Specialized Research Center, Department of Molecular Physiology and Biophysics and Department of Neurology, Roy J. and Lucille A. Carver College of Medicine, The University of IowaIowa CityUnited States
| | - Jeffrey M Hord
- Howard Hughes Medical Institute, Senator Paul D. Wellstone Muscular Dystrophy Specialized Research Center, Department of Molecular Physiology and Biophysics and Department of Neurology, Roy J. and Lucille A. Carver College of Medicine, The University of IowaIowa CityUnited States
| | - Ishita Chandel
- Howard Hughes Medical Institute, Senator Paul D. Wellstone Muscular Dystrophy Specialized Research Center, Department of Molecular Physiology and Biophysics and Department of Neurology, Roy J. and Lucille A. Carver College of Medicine, The University of IowaIowa CityUnited States
| | - David Venzke
- Howard Hughes Medical Institute, Senator Paul D. Wellstone Muscular Dystrophy Specialized Research Center, Department of Molecular Physiology and Biophysics and Department of Neurology, Roy J. and Lucille A. Carver College of Medicine, The University of IowaIowa CityUnited States
| | - Mary E Anderson
- Howard Hughes Medical Institute, Senator Paul D. Wellstone Muscular Dystrophy Specialized Research Center, Department of Molecular Physiology and Biophysics and Department of Neurology, Roy J. and Lucille A. Carver College of Medicine, The University of IowaIowa CityUnited States
| | - Ameya S Walimbe
- Howard Hughes Medical Institute, Senator Paul D. Wellstone Muscular Dystrophy Specialized Research Center, Department of Molecular Physiology and Biophysics and Department of Neurology, Roy J. and Lucille A. Carver College of Medicine, The University of IowaIowa CityUnited States
| | - Soumya Joseph
- Howard Hughes Medical Institute, Senator Paul D. Wellstone Muscular Dystrophy Specialized Research Center, Department of Molecular Physiology and Biophysics and Department of Neurology, Roy J. and Lucille A. Carver College of Medicine, The University of IowaIowa CityUnited States
| | - Zeita Gastel
- Howard Hughes Medical Institute, Senator Paul D. Wellstone Muscular Dystrophy Specialized Research Center, Department of Molecular Physiology and Biophysics and Department of Neurology, Roy J. and Lucille A. Carver College of Medicine, The University of IowaIowa CityUnited States
| | - Yuji Hara
- Department Pharmaceutical Sciences, School of Pharmaceutical Sciences, University of ShizuokaShizuokaJapan
| | - Fumiaki Saito
- Department of Neurology, School of Medicine, Teikyo UniversityTokyoJapan
| | - Kiichiro Matsumura
- Department of Neurology, School of Medicine, Teikyo UniversityTokyoJapan
| | - Kevin P Campbell
- Howard Hughes Medical Institute, Senator Paul D. Wellstone Muscular Dystrophy Specialized Research Center, Department of Molecular Physiology and Biophysics and Department of Neurology, Roy J. and Lucille A. Carver College of Medicine, The University of IowaIowa CityUnited States
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4
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Sheikh MO, Capicciotti CJ, Liu L, Praissman J, Ding D, Mead DG, Brindley MA, Willer T, Campbell KP, Moremen KW, Wells L, Boons GJ. Cell surface glycan engineering reveals that matriglycan alone can recapitulate dystroglycan binding and function. Nat Commun 2022; 13:3617. [PMID: 35750689 PMCID: PMC9232514 DOI: 10.1038/s41467-022-31205-7] [Citation(s) in RCA: 20] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2021] [Accepted: 06/07/2022] [Indexed: 12/29/2022] Open
Abstract
α-Dystroglycan (α-DG) is uniquely modified on O-mannose sites by a repeating disaccharide (-Xylα1,3-GlcAβ1,3-)n termed matriglycan, which is a receptor for laminin-G domain-containing proteins and employed by old-world arenaviruses for infection. Using chemoenzymatically synthesized matriglycans printed as a microarray, we demonstrate length-dependent binding to Laminin, Lassa virus GP1, and the clinically-important antibody IIH6. Utilizing an enzymatic engineering approach, an N-linked glycoprotein was converted into a IIH6-positive Laminin-binding glycoprotein. Engineering of the surface of cells deficient for either α-DG or O-mannosylation with matriglycans of sufficient length recovers infection with a Lassa-pseudovirus. Finally, free matriglycan in a dose and length dependent manner inhibits viral infection of wildtype cells. These results indicate that matriglycan alone is necessary and sufficient for IIH6 staining, Laminin and LASV GP1 binding, and Lassa-pseudovirus infection and support a model in which it is a tunable receptor for which increasing chain length enhances ligand-binding capacity.
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Affiliation(s)
- M Osman Sheikh
- Complex Carbohydrate Research Center, University of Georgia, Athens, GA, USA
| | - Chantelle J Capicciotti
- Complex Carbohydrate Research Center, University of Georgia, Athens, GA, USA
- Departments of Chemistry, Biomedical and Molecular Sciences, and Surgery, Queen's University, Kingston, ON, Canada
| | - Lin Liu
- Complex Carbohydrate Research Center, University of Georgia, Athens, GA, USA
| | - Jeremy Praissman
- Complex Carbohydrate Research Center, University of Georgia, Athens, GA, USA
| | - Dahai Ding
- Complex Carbohydrate Research Center, University of Georgia, Athens, GA, USA
- Department of Chemistry, University of Georgia, Athens, GA, USA
| | - Daniel G Mead
- College of Veterinary Medicine, University of Georgia, Athens, GA, USA
| | | | - Tobias Willer
- Howard Hughes Medical Institute, Senator Paul D. Wellstone Muscular Dystrophy Specialized Research Center, Department of Molecular Physiology and Biophysics, The University of Iowa, Iowa City, IA, USA
- Department of Neurology, Roy J. and Lucille A. Carver College of Medicine, The University of Iowa, Iowa City, IA, USA
| | - Kevin P Campbell
- Howard Hughes Medical Institute, Senator Paul D. Wellstone Muscular Dystrophy Specialized Research Center, Department of Molecular Physiology and Biophysics, The University of Iowa, Iowa City, IA, USA
- Department of Neurology, Roy J. and Lucille A. Carver College of Medicine, The University of Iowa, Iowa City, IA, USA
| | - Kelley W Moremen
- Complex Carbohydrate Research Center, University of Georgia, Athens, GA, USA
- Department of Biochemistry & Molecular Biology, University of Georgia, Athens, GA, USA
| | - Lance Wells
- Complex Carbohydrate Research Center, University of Georgia, Athens, GA, USA.
- Department of Biochemistry & Molecular Biology, University of Georgia, Athens, GA, USA.
| | - Geert-Jan Boons
- Complex Carbohydrate Research Center, University of Georgia, Athens, GA, USA.
- Department of Chemistry, University of Georgia, Athens, GA, USA.
- Department of Chemical Biology and Drug Discovery, Utrecht University, Utrecht, The Netherlands.
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5
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Hang J, Wang J, Lu M, Xue Y, Qiao J, Tao L. Protein O-mannosylation across kingdoms and related diseases: From glycobiology to glycopathology. Biomed Pharmacother 2022; 148:112685. [PMID: 35149389 DOI: 10.1016/j.biopha.2022.112685] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2021] [Revised: 01/29/2022] [Accepted: 02/01/2022] [Indexed: 11/18/2022] Open
Abstract
The post-translational glycosylation of proteins by O-linked α-mannose is conserved from bacteria to humans. Due to advances in high-throughput mass spectrometry-based approaches, a variety of glycoproteins are identified to be O-mannosylated. Various proteins with O-mannosylation are involved in biological processes, providing essential necessity for proper growth and development. In this review, we summarize the process and regulation of O-mannosylation. The multi-step O-mannosylation procedures are quite dynamic and complex, especially when considering the structural and functional inspection of the involved enzymes. The widely studied O-mannosylated proteins in human include α-Dystroglycan (α-DG), cadherins, protocadherins, and plexin, and their aberrant O-mannosylation are associated with many diseases. In addition, O-mannosylation also contributes to diverse functions in lower eukaryotes and prokaryotes. Finally, we present the relationship between O-mannosylation and gut microbiota (GM), and elucidate that O-mannosylation in microbiome is of great importance in the dynamic balance of GM. Our study provides an overview of the processes of O-mannosylation in mammalian cells and other organisms, and also associated regulated enzymes and biological functions, which could contribute to the understanding of newly discovered O-mannosylated glycoproteins.
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Affiliation(s)
- Jing Hang
- Center for Reproductive Medicine, Department of Obstetrics and Gynecology, Peking University Third Hospital, Beijing 100191, China; National Clinical Research Center for Obstetrics and Gynecology (Peking University Third Hospital), Beijing 100191, China; Key Laboratory of Assisted Reproduction (Peking University), Ministry of Education, Beijing 100191, China; Beijing Key Laboratory of Reproductive Endocrinology and Assisted Reproductive Technology, Beijing 100191, China
| | - Jinpeng Wang
- Department of Orthopedics, First Hospital of China Medical University, Shenyang 110001, China
| | - Minzhen Lu
- Center for Reproductive Medicine, Department of Obstetrics and Gynecology, Peking University Third Hospital, Beijing 100191, China; National Clinical Research Center for Obstetrics and Gynecology (Peking University Third Hospital), Beijing 100191, China; Key Laboratory of Assisted Reproduction (Peking University), Ministry of Education, Beijing 100191, China; Beijing Key Laboratory of Reproductive Endocrinology and Assisted Reproductive Technology, Beijing 100191, China
| | - Yuchuan Xue
- The First Department of Clinical Medicine, China Medical University, Shenyang 110001, China
| | - Jie Qiao
- Center for Reproductive Medicine, Department of Obstetrics and Gynecology, Peking University Third Hospital, Beijing 100191, China; National Clinical Research Center for Obstetrics and Gynecology (Peking University Third Hospital), Beijing 100191, China; Key Laboratory of Assisted Reproduction (Peking University), Ministry of Education, Beijing 100191, China; Beijing Key Laboratory of Reproductive Endocrinology and Assisted Reproductive Technology, Beijing 100191, China.
| | - Lin Tao
- Department of Orthopedics, First Hospital of China Medical University, Shenyang 110001, China.
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6
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Fan L, Miura S, Shimojo T, Sugino H, Fujioka R, Shibata H. A novel 1-bp deletion variant in DAG1 in Japanese familial asymptomatic hyper-CK-emia. Hum Genome Var 2022; 9:4. [PMID: 35082294 PMCID: PMC8791931 DOI: 10.1038/s41439-022-00182-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2021] [Revised: 12/27/2021] [Accepted: 01/05/2022] [Indexed: 01/11/2023] Open
Abstract
Asymptomatic hyper-CK-emia (ASCK) is characterized by persistent elevation of creatine kinase (CK) in serum without any neurological symptoms. We ascertained a two-generation family of ASCK patients without clear neurological abnormalities except for the high levels of serum CK (810.5 ± 522.4 U/L). We identified a novel 1-bp deletion variant in the DAG1 gene shared by the patients in the family (NM_001177639: exon 3: c.930delC:p.R311Gfs*70). The variant causes premature termination of translation at codon 477, resulting in a protein product completely devoid of the essential DAG1 domain. Since ASCK has been associated with DAG1 in only one case carrying compound heterozygous missense variants, our new finding of a novel 1-bp deletion revealed the previously unknown dominant effect of DAG1 on ASCK.
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Affiliation(s)
- Luoming Fan
- grid.177174.30000 0001 2242 4849Division of Genomics, Medical Institute of Bioregulation, Kyushu University, Fukuoka, Japan
| | - Shiroh Miura
- grid.255464.40000 0001 1011 3808Department of Neurology and Geriatric Medicine, Ehime University Graduate School of Medicine, Ehime, Japan
| | - Tomofumi Shimojo
- grid.177174.30000 0001 2242 4849Division of Genomics, Medical Institute of Bioregulation, Kyushu University, Fukuoka, Japan
| | | | - Ryuta Fujioka
- grid.443342.60000 0001 0664 6230Department of Food and Nutrition, Beppu University Junior College, Oita, Japan
| | - Hiroki Shibata
- grid.177174.30000 0001 2242 4849Division of Genomics, Medical Institute of Bioregulation, Kyushu University, Fukuoka, Japan
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Cuttler K, Hassan M, Carr J, Cloete R, Bardien S. Emerging evidence implicating a role for neurexins in neurodegenerative and neuropsychiatric disorders. Open Biol 2021; 11:210091. [PMID: 34610269 PMCID: PMC8492176 DOI: 10.1098/rsob.210091] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
Synaptopathies are brain disorders characterized by dysfunctional synapses, which are specialized junctions between neurons that are essential for the transmission of information. Synaptic dysfunction can occur due to mutations that alter the structure and function of synaptic components or abnormal expression levels of a synaptic protein. One class of synaptic proteins that are essential to their biology are cell adhesion proteins that connect the pre- and post-synaptic compartments. Neurexins are one type of synaptic cell adhesion molecule that have, recently, gained more pathological interest. Variants in both neurexins and their common binding partners, neuroligins, have been associated with several neuropsychiatric disorders. In this review, we summarize some of the key physiological functions of the neurexin protein family and the protein networks they are involved in. Furthermore, examination of published literature has implicated neurexins in both neuropsychiatric and neurodegenerative disorders. There is a clear link between neurexins and neuropsychiatric disorders, such as autism spectrum disorder and schizophrenia. However, multiple expression studies have also shown changes in neurexin expression in several neurodegenerative disorders, including Alzheimer's disease and Parkinson's disease. Therefore, this review highlights the potential importance of neurexins in brain disorders and the importance of doing more targeted studies on these genes and proteins.
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Affiliation(s)
- Katelyn Cuttler
- Division of Molecular Biology and Human Genetics, Department of Biomedical Sciences, Stellenbosch University, Cape Town, South Africa
| | - Maryam Hassan
- South African Medical Research Council Bioinformatics Unit, South African National Bioinformatics Institute, University of the Western Cape, Cape Town, South Africa
| | - Jonathan Carr
- Division of Neurology, Department of Medicine, Faculty of Medicine and Health Sciences, Stellenbosch University, Cape Town, South Africa,South African Medical Research Council/Stellenbosch University Genomics of Brain Disorders Research Unit, Cape Town, South Africa
| | - Ruben Cloete
- South African Medical Research Council Bioinformatics Unit, South African National Bioinformatics Institute, University of the Western Cape, Cape Town, South Africa
| | - Soraya Bardien
- Division of Molecular Biology and Human Genetics, Department of Biomedical Sciences, Stellenbosch University, Cape Town, South Africa,South African Medical Research Council/Stellenbosch University Genomics of Brain Disorders Research Unit, Cape Town, South Africa
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8
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Song D, Dai Y, Chen X, Fu X, Chang X, Wang N, Zhang C, Yan C, Zheng H, Wu L, Jiang L, Hua Y, Yang H, Wang Z, Dai T, Zhu W, Han C, Yuan Y, Kobayashi K, Toda T, Xiong H. Genetic variations and clinical spectrum of dystroglycanopathy in a large cohort of Chinese patients. Clin Genet 2021; 99:384-395. [PMID: 33200426 DOI: 10.1111/cge.13886] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2020] [Revised: 10/27/2020] [Accepted: 11/12/2020] [Indexed: 12/18/2022]
Abstract
Dystroglycanopathy is a group of muscular dystrophies with deficient glycosylation of alpha-dystroglycan (α-DG). We recruited patients from 36 tertiary academic hospitals in China. In total, 143 patients with genetically diagnosed dystroglycanopathy were enrolled. Of these, limb girdle muscular dystrophy was the most common initial diagnosis (83 patients) and Walker-Warburg syndrome was the least common (1 patient). In 143 patients, mutations in FKRP gene were the most prevalent (62 patients), followed by POMT2, POMT1 (16), POMGNT1, ISPD (14), FKTN, GMPPB, B3GALNT2, DPM3, and DAG1. Several frequent mutations were identified in FKRP, POMT1, POMGNT1, ISPD, and FKTN genes. Many of these were founder mutations. Patients with FKRP mutations tended to have milder phenotypes, while those with mutations in POMGNT1 genes had more severe phenotypes. Mental retardation was a clinical feature associated with mutations of POMT1 gene. Detailed clinical data of 83 patients followed up in Peking University First Hospital were further analyzed. Our clinical and genetic analysis of a large cohort of Chinese patients with dystroglycanopathy expanded the genotype variation and clinical spectrum of congenital muscular dystrophies.
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Affiliation(s)
- Danyu Song
- Department of Pediatrics, Peking University First Hospital, Beijing, China
| | - Yi Dai
- Department of Neurology, Peking Union Medical College Hospital, Peking Union Medical College and Chinese Academy of Medical Sciences, Beijing, China
| | - Xiaoyu Chen
- Department of Pediatrics, Peking University First Hospital, Beijing, China
| | - Xiaona Fu
- Department of Pediatrics, Peking University First Hospital, Beijing, China
| | - Xingzhi Chang
- Department of Pediatrics, Peking University First Hospital, Beijing, China
| | - Ning Wang
- Department of Neurology and Institute of Neurology, First Affiliated Hospital of Fujian Medical University, Fuzhou, China
| | - Cheng Zhang
- Department of Neurology, First Affiliated Hospital of Sun Yat-sen University, Guangzhou, China
| | - Chuanzhu Yan
- Department of Neurology, Qilu Hospital, Shandong University, Jinan, China
| | - Hong Zheng
- Department of Pediatrics, the First Affiliated Hospital of Henan University of Chinese Medicine, Zhengzhou, China
| | - Liwen Wu
- Department of Neurology, Hunan Children's Hospital, Changsha, China
| | - Li Jiang
- Department of Neurology, Children's Hospital of Chongqing Medical University, Chongqing, China
| | - Ying Hua
- Department of Neurology, Wuxi Children's Hospital, Wuxi, China
| | - Haipo Yang
- Department of Pediatrics, Peking University First Hospital, Beijing, China
| | - Zhiqiang Wang
- Department of Neurology and Institute of Neurology, First Affiliated Hospital of Fujian Medical University, Fuzhou, China
| | - Tingjun Dai
- Department of Neurology, Qilu Hospital, Shandong University, Jinan, China
| | - Wenhua Zhu
- Department of Neurology, Huashan Hospital, Fudan University, Shanghai, China
| | - Chunxi Han
- Department of Neurology, Shenzhen Children's Hospital, Shenzhen, China
| | - Yun Yuan
- Department of Neurology, Peking University First Hospital, Beijing, China
| | - Kazuhiro Kobayashi
- Division of Neurology/Molecular Brain Science, Kobe University Graduate School of Medicine, Kobe, Japan
| | - Tatsushi Toda
- Department of Neurology, Graduate School of Medicine, the University of Tokyo, Tokyo, Japan
| | - Hui Xiong
- Department of Pediatrics, Peking University First Hospital, Beijing, China
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9
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Finsterer J, Scorza FA, Scorza CA. Significance of Asymptomatic Hyper Creatine-Kinase Emia. J Clin Neuromuscul Dis 2019; 21:90-102. [PMID: 31743252 DOI: 10.1097/cnd.0000000000000269] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
OBJECTIVES Whether asymptomatic hyper-CKemia (AHCE) should prompt a thorough work-up for muscle disease or not is controversially discussed. This review aims at summarizing and discussing recent findings concerning the cause, frequency, evolution, and work-up of conditions manifesting as AHCE and normal or abnormal electromyography (EMG) respectively muscle biopsy. METHODS Systematic PubMed search. RESULTS There are numerous primary (hereditary) and acquired myopathies that manifest with permanent, recurrent, or temporary AHCE with/without myopathic EMG or muscle biopsy. AHCE particularly occurs at onset of these conditions, which include dystrophinopathies, myotilinopathies, calpainopathy, caveolinopathy, dysferlinopathy, central core disease, multicore disease, desminopathy, MD1, MD2, hypoPP, malignant hyperthermia susceptibility, Pompe disease, McArdle disease, myoadenylate deaminase-deficiency, CPT2-deficiency, mitochondrial disorders, or myopathy with tubular aggregates. Most likely, other primary myopathies manifest with AHCE as well, without having been reported. Patients with AHCE should be taken seriously and repeated CK determination must be conducted. If hyper-CKemia is persisting or recurrent, these patients should undergo an EMG and eventually muscle biopsy. If noninformative, genetic work-up by a panel or whole exome sequencing should be initiated, irrespective of the family history. Patients with AHCE should avoid excessive exercise, require sufficient hydration, require counseling with regard to the risk of malignant hyperthermia, and should inform anesthesiologists and surgeons about their condition before elective surgery. CONCLUSIONS Recurrent AHCE should be taken seriously and managed with conventional work-up. If noninformative, genetic work-up should follow irrespective of the family history.
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Affiliation(s)
- Josef Finsterer
- Krankenanstalt Rudolfstiftung, Messerli Institute, Vienna, Austria
| | - Fulvio A Scorza
- Disciplina de Neurociência, Escola Paulista de Medicine/Universidade Federal de São Paulo (EPM/UNIFESP), São Paulo, Brazil
| | - Carla A Scorza
- Disciplina de Neurociência, Escola Paulista de Medicine/Universidade Federal de São Paulo (EPM/UNIFESP), São Paulo, Brazil
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10
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Brancaccio A. A molecular overview of the primary dystroglycanopathies. J Cell Mol Med 2019; 23:3058-3062. [PMID: 30838779 PMCID: PMC6484290 DOI: 10.1111/jcmm.14218] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2018] [Revised: 01/22/2019] [Accepted: 01/23/2019] [Indexed: 01/17/2023] Open
Abstract
Dystroglycan is a major non-integrin adhesion complex that connects the cytoskeleton to the surrounding basement membranes, thus providing stability to skeletal muscle. In Vertebrates, hypoglycosylation of α-dystroglycan has been strongly linked to muscular dystrophy phenotypes, some of which also show variable degrees of cognitive impairments, collectively termed dystroglycanopathies. Only a small number of mutations in the dystroglycan gene, leading to the so called primary dystroglycanopathies, has been described so far, as opposed to the ever-growing number of identified secondary or tertiary dystroglycanopathies (caused by genetic abnormalities in glycosyltransferases or in enzymes involved in the synthesis of the carbohydrate building blocks). The few mutations found within the autonomous N-terminal domain of α-dystroglycan seem to destabilise it to different degrees, without influencing the overall folding and targeting of the dystroglycan complex. On the contrary other mutations, some located at the α/β interface of the dystroglycan complex, seem to be able to interfere with its maturation, thus compromising its stability and eventually leading to the intracellular engulfment and/or partial or even total degradation of the dystroglycan uncleaved precursor.
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Affiliation(s)
- Andrea Brancaccio
- School of Biochemistry, University of Bristol, Bristol, UK.,Istituto di Chimica del Riconoscimento Molecolare - CNR c/o Università Cattolica del Sacro Cuore, Roma, Italy
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11
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ENDO T. Mammalian O-mannosyl glycans: Biochemistry and glycopathology. PROCEEDINGS OF THE JAPAN ACADEMY. SERIES B, PHYSICAL AND BIOLOGICAL SCIENCES 2019; 95:39-51. [PMID: 30643095 PMCID: PMC6395781 DOI: 10.2183/pjab.95.004] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/05/2018] [Accepted: 11/05/2018] [Indexed: 05/20/2023]
Abstract
Glycosylation is an important posttranslational modification in mammals. The glycans of glycoproteins are classified into two groups, namely, N-glycans and O-glycans, according to their glycan-peptide linkage regions. Recently, O-mannosyl glycan, an O-glycan, has been shown to be important in muscle and brain development. A clear relationship between O-mannosyl glycans and the pathomechanisms of some congenital muscular dystrophies has been established in humans. Ribitol-5-phosphate is a newly identified glycan component in mammals, and its biosynthetic pathway has been elucidated. The discovery of new glycan structures and the identification of highly regulated mechanisms of glycan processing will help researchers to understand glycan functions and develop therapeutic strategies.
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Affiliation(s)
- Tamao ENDO
- Tokyo Metropolitan Institute of Gerontology, Tokyo, Japan
- Correspondence should be addressed: T. Endo, Tokyo Metropolitan Institute of Gerontology, 35-2 Sakaecho, Itabashi-ku, Tokyo 173-0015, Japan (e-mail: )
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12
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Sarkozy A, Torelli S, Mein R, Henderson M, Phadke R, Feng L, Sewry C, Ala P, Yau M, Bertoli M, Willis T, Hammans S, Manzur A, Sframeli M, Norwood F, Rakowicz W, Radunovic A, Vaidya SS, Parton M, Walker M, Marino S, Offiah C, Farrugia ME, Mamutse G, Marini-Bettolo C, Wraige E, Beeson D, Lochmüller H, Straub V, Bushby K, Barresi R, Muntoni F. Mobility shift of beta-dystroglycan as a marker of GMPPB gene-related muscular dystrophy. J Neurol Neurosurg Psychiatry 2018; 89:762-768. [PMID: 29437916 DOI: 10.1136/jnnp-2017-316956] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/26/2017] [Revised: 12/20/2017] [Accepted: 01/03/2018] [Indexed: 12/13/2022]
Abstract
BACKGROUND Defects in glycosylation of alpha-dystroglycan (α-DG) cause autosomal-recessive disorders with wide clinical and genetic heterogeneity, with phenotypes ranging from congenital muscular dystrophies to milder limb girdle muscular dystrophies. Patients show variable reduction of immunoreactivity to antibodies specific for glycoepitopes of α-DG on a muscle biopsy. Recessive mutations in 18 genes, including guanosine diphosphate mannose pyrophosphorylase B (GMPPB), have been reported to date. With no specific clinical and pathological handles, diagnosis requires parallel or sequential analysis of all known genes. METHODS We describe clinical, genetic and biochemical findings of 21 patients with GMPPB-associated dystroglycanopathy. RESULTS We report eight novel mutations and further expand current knowledge on clinical and muscle MRI features of this condition. In addition, we report a consistent shift in the mobility of beta-dystroglycan (β-DG) on Western blot analysis of all patients analysed by this mean. This was only observed in patients with GMPPB in our large dystroglycanopathy cohort. We further demonstrate that this mobility shift in patients with GMPPB was due to abnormal N-linked glycosylation of β-DG. CONCLUSIONS Our data demonstrate that a change in β-DG electrophoretic mobility in patients with dystroglycanopathy is a distinctive marker of the molecular defect in GMPPB.
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Affiliation(s)
- Anna Sarkozy
- Dubowitz Neuromuscular Centre, MRC Centre for Neuromuscular Diseases, UCL Great Ormond Street Institute of Child Health, London, UK
| | - Silvia Torelli
- Dubowitz Neuromuscular Centre, MRC Centre for Neuromuscular Diseases, UCL Great Ormond Street Institute of Child Health, London, UK
| | - Rachael Mein
- DNA Laboratory, Viapath, Guy's Hospital, London, UK
| | - Matt Henderson
- Rare Diseases Advisory Group Service for Neuromuscular Diseases, Muscle Immunoanalysis Unit, Dental Hospital, Newcastle upon Tyne, UK
| | - Rahul Phadke
- Dubowitz Neuromuscular Centre, MRC Centre for Neuromuscular Diseases, UCL Great Ormond Street Institute of Child Health, London, UK
| | - Lucy Feng
- Dubowitz Neuromuscular Centre, MRC Centre for Neuromuscular Diseases, UCL Great Ormond Street Institute of Child Health, London, UK
| | - Caroline Sewry
- Dubowitz Neuromuscular Centre, MRC Centre for Neuromuscular Diseases, UCL Great Ormond Street Institute of Child Health, London, UK.,The Robert Jones and Agnes Hunt Orthopaedic Hospital, Oswestry, UK
| | - Pierpaolo Ala
- Dubowitz Neuromuscular Centre, MRC Centre for Neuromuscular Diseases, UCL Great Ormond Street Institute of Child Health, London, UK
| | - Michael Yau
- DNA Laboratory, Viapath, Guy's Hospital, London, UK
| | - Marta Bertoli
- The John Walton Muscular Dystrophy Research Centre, MRC Centre for Neuromuscular Diseases Institute of Genetic Medicine, University of Newcastle, Newcastle upon Tyne, UK.,Northern Genetics Service, Newcastle upon Tyne NHS Trust, Newcastle upon Tyne, UK
| | - Tracey Willis
- The Robert Jones and Agnes Hunt Orthopaedic Hospital, Oswestry, UK
| | - Simon Hammans
- Wessex Neurological Centre, University Hospital of Southampton, Southampton, UK
| | - Adnan Manzur
- Dubowitz Neuromuscular Centre, MRC Centre for Neuromuscular Diseases, UCL Great Ormond Street Institute of Child Health, London, UK
| | - Maria Sframeli
- Dubowitz Neuromuscular Centre, MRC Centre for Neuromuscular Diseases, UCL Great Ormond Street Institute of Child Health, London, UK
| | - Fiona Norwood
- Department of Neurology, King's College Hospital, London, UK
| | - Wojtek Rakowicz
- Department of Neurology, Hampshire Hospitals NHS Foundation Trust, Royal Hampshire County Hospital, Winchester, UK
| | | | | | - Matt Parton
- MRC Centre for Neuromuscular Diseases, Institute of Neurology, University College London, London, UK
| | - Mark Walker
- Department of Cellular Pathology, Southampton University Hospitals, Southampton, UK
| | - Silvia Marino
- Queen Mary University of London, Barts and the London School of Medicine and Dentistry, London, UK
| | - Curtis Offiah
- Department of Radiology, Royal London Hospital, London, UK
| | - Maria Elena Farrugia
- Department of Neurology, Institute of Neurological Sciences, Southern General Hospital, Glasgow, UK
| | - Godwin Mamutse
- Department of Neurology, Norfolk and Norwich University Hospital, Norwich, UK
| | - Chiara Marini-Bettolo
- The John Walton Muscular Dystrophy Research Centre, MRC Centre for Neuromuscular Diseases Institute of Genetic Medicine, University of Newcastle, Newcastle upon Tyne, UK
| | - Elizabeth Wraige
- Department of Paediatric Neurology, Neuromuscular Service, Evelina Children's Hospital, St Thomas' Hospital, London, UK
| | - David Beeson
- Neuromuscular Disorders Group, Nuffield Department of Clinical Neurosciences, Weatherall Institute of Molecular Medicine, Oxford, UK
| | - Hanns Lochmüller
- The John Walton Muscular Dystrophy Research Centre, MRC Centre for Neuromuscular Diseases Institute of Genetic Medicine, University of Newcastle, Newcastle upon Tyne, UK
| | - Volker Straub
- The John Walton Muscular Dystrophy Research Centre, MRC Centre for Neuromuscular Diseases Institute of Genetic Medicine, University of Newcastle, Newcastle upon Tyne, UK
| | - Kate Bushby
- The John Walton Muscular Dystrophy Research Centre, MRC Centre for Neuromuscular Diseases Institute of Genetic Medicine, University of Newcastle, Newcastle upon Tyne, UK
| | - Rita Barresi
- Rare Diseases Advisory Group Service for Neuromuscular Diseases, Muscle Immunoanalysis Unit, Dental Hospital, Newcastle upon Tyne, UK.,The John Walton Muscular Dystrophy Research Centre, MRC Centre for Neuromuscular Diseases Institute of Genetic Medicine, University of Newcastle, Newcastle upon Tyne, UK
| | - Francesco Muntoni
- Dubowitz Neuromuscular Centre, MRC Centre for Neuromuscular Diseases, UCL Great Ormond Street Institute of Child Health, London, UK
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13
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Theodoraki E, Orfanoudaki E, Foteinogiannopoulou K, Koutroubakis IE. Asymptomatic hyperCKemia During Infliximab Therapy in Patients With Inflammatory Bowel Disease. Inflamm Bowel Dis 2018; 24:1266-1271. [PMID: 29718260 DOI: 10.1093/ibd/izy088] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
BACKGROUND Both muscle-related complaints and elevated serum creatine kinase (CK) levels have been reported in patients with inflammatory bowel disease (IBD) treated with infliximab (IFX), mainly as case reports. The aim of this study was to investigate the effect of IFX therapy on serum CK levels in a cohort of Greek IBD patients. METHODS Demographic, clinical (including muscle complaints), and laboratory data of consecutive IBD patients undergoing IFX treatment and a matched control group of IBD patients without any use of biological treatment were retrospectively analyzed. In both groups, patients having at least 3 CK measurements, with at least 10 days' interval among them, were included. RESULTS The IFX-treated IBD patient group included 82 individuals (75.6% Crohn's Disease [CD]; mean age, 44.7 ± 13.3 years; 60.9% men; median [interquartile range {IQR}] duration of IFX treatment, 27 [12-84] months). Eighty-two patients without treatment with any biological agent formed the control group (62.2% CD; mean age, 50.4 ± 16.4 years; 59.8% men). Twenty-five IFX-treated patients (30.5%) had elevated mean serum CK levels (>180 U/L), compared with 9 (11%) in the control group (P = 0.0003). The median CK value in the IFX group (123.5 U/L; IQR, 91-190.75) was significantly higher than that of the control group (81 U/L; IQR, 57-112.75; P < 0.0001). In the logistic regression analysis, the presence of hyperCKemia was independently correlated with the use of IFX (odds ratio, 4.03; IQR, 1.64-9.90; P = 0.002). No patient with hyperCKemia in both groups reported any persistent symptom of myopathy. CONCLUSIONS More than 30% of IBD patients on IFX present asymptomatic persistent and treatment-related hyperCKemia. Further relevant prospective investigation is needed. 10.1093/ibd/izy088_video1izy088.video15778459427001.
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Affiliation(s)
- Eirini Theodoraki
- Department of Gastroenterology, University Hospital of Heraklion, Greece, Heraklion, Greece
| | - Eleni Orfanoudaki
- Department of Gastroenterology, University Hospital of Heraklion, Greece, Heraklion, Greece
| | | | - Ioannis E Koutroubakis
- Department of Gastroenterology, University Hospital of Heraklion, Greece, Heraklion, Greece
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14
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Leibovitz Z, Mandel H, Falik-Zaccai TC, Ben Harouch S, Savitzki D, Krajden-Haratz K, Gindes L, Tamarkin M, Lev D, Dobyns WB, Lerman-Sagie T. Walker-Warburg syndrome and tectocerebellar dysraphia: A novel association caused by a homozygous DAG1 mutation. Eur J Paediatr Neurol 2018; 22:525-531. [PMID: 29337005 DOI: 10.1016/j.ejpn.2017.12.012] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/21/2017] [Revised: 11/25/2017] [Accepted: 12/18/2017] [Indexed: 01/09/2023]
Abstract
OBJECTIVES To elaborate the imaging phenotype associated with a homozygous c.743C > del frameshift mutation in DAG1 leading to complete absence of both α- and β-dystroglycan previously reported in a consanguineous Israeli-Arab family. METHODS We analyzed prenatal and postnatal imaging data of patients from a consanguineous Israeli-Arab kindred harboring the DAG1 mutation. RESULTS The imaging studies (fetal ultrasound, CT scan and postnatal MRI) demonstrated: flat cortex (abnormally thick with irregular pebbled cortical-white matter border on MRI), hydrocephalus, scattered small periventricular heterotopia and subependymal hemorrhages and calcifications, z-shaped brainstem, and in addition an occipital encephalocele, vermian agenesis, and an elongated and thick tectum (tectocerebellar dysraphia). CONCLUSIONS The novel association of cobblestone malformation with tectocerebellar dysraphia as part of WWS is characteristic of the homozygous c.743C > del frameshift mutation in the DAG1 gene.
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Affiliation(s)
- Zvi Leibovitz
- Obstetrics-Gynecology Ultrasound Unit, Bnai-Zion Medical Center and Rappoport Faculty of Medicine, The Technion, Haifa, Israel; Fetal Neurology Clinic, Obstetrics-Gynecology Ultrasound Unit, Department of Obstetrics and Gynecology, Wolfson Medical Center, Holon and Sackler School of Medicine, Tel-Aviv University, Tel-Aviv, Israel.
| | - Hanna Mandel
- Institute of Human Genetics and Metabolic Disorders, Western Galilee Medical Center, Naharia and Faculty of Medicine in the Galilee, Bar Ilan University, Safed, Israel
| | - Tzipora C Falik-Zaccai
- Institute of Human Genetics and Metabolic Disorders, Western Galilee Medical Center, Naharia and Faculty of Medicine in the Galilee, Bar Ilan University, Safed, Israel
| | - Shani Ben Harouch
- Institute of Human Genetics and Metabolic Disorders, Western Galilee Medical Center, Naharia and Faculty of Medicine in the Galilee, Bar Ilan University, Safed, Israel
| | - David Savitzki
- Pediatric Neurology and Development Unit, Western Galilee Medical Center, Naharia and Faculty of Medicine in the Galilee, Bar Ilan University, Safed, Israel
| | - Karina Krajden-Haratz
- Fetal Neurology Clinic, Obstetrics-Gynecology Ultrasound Unit, Department of Obstetrics and Gynecology, Wolfson Medical Center, Holon and Sackler School of Medicine, Tel-Aviv University, Tel-Aviv, Israel
| | - Liat Gindes
- Fetal Neurology Clinic, Obstetrics-Gynecology Ultrasound Unit, Department of Obstetrics and Gynecology, Wolfson Medical Center, Holon and Sackler School of Medicine, Tel-Aviv University, Tel-Aviv, Israel
| | - Mordechai Tamarkin
- Fetal Neurology Clinic, Obstetrics-Gynecology Ultrasound Unit, Department of Obstetrics and Gynecology, Wolfson Medical Center, Holon and Sackler School of Medicine, Tel-Aviv University, Tel-Aviv, Israel
| | - Dorit Lev
- Fetal Neurology Clinic, Obstetrics-Gynecology Ultrasound Unit, Department of Obstetrics and Gynecology, Wolfson Medical Center, Holon and Sackler School of Medicine, Tel-Aviv University, Tel-Aviv, Israel; The Rina Mor Institute of Medical Genetics, Wolfson Medical Center, Holon and Sackler School of Medicine, Tel-Aviv University, Tel-Aviv, Israel
| | - William B Dobyns
- Center for Integrative Brain Research, Seattle Children's Research Institute, Seattle, WA, USA
| | - Tally Lerman-Sagie
- Fetal Neurology Clinic, Obstetrics-Gynecology Ultrasound Unit, Department of Obstetrics and Gynecology, Wolfson Medical Center, Holon and Sackler School of Medicine, Tel-Aviv University, Tel-Aviv, Israel; Pediatric Neurology Unit, Wolfson Medical Center, Holon and Sackler School of Medicine, Tel-Aviv University, Tel-Aviv, Israel
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15
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Signorino G, Covaceuszach S, Bozzi M, Hübner W, Mönkemöller V, Konarev PV, Cassetta A, Brancaccio A, Sciandra F. A dystroglycan mutation (p.Cys667Phe) associated to muscle-eye-brain disease with multicystic leucodystrophy results in ER-retention of the mutant protein. Hum Mutat 2017; 39:266-280. [PMID: 29134705 DOI: 10.1002/humu.23370] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2017] [Revised: 10/13/2017] [Accepted: 11/06/2017] [Indexed: 01/11/2023]
Abstract
Dystroglycan (DG) is a cell adhesion complex composed by two subunits, the highly glycosylated α-DG and the transmembrane β-DG. In skeletal muscle, DG is involved in dystroglycanopathies, a group of heterogeneous muscular dystrophies characterized by a reduced glycosylation of α-DG. The genes mutated in secondary dystroglycanopathies are involved in the synthesis of O-mannosyl glycans and in the O-mannosylation pathway of α-DG. Mutations in the DG gene (DAG1), causing primary dystroglycanopathies, destabilize the α-DG core protein influencing its binding to modifying enzymes. Recently, a homozygous mutation (p.Cys699Phe) hitting the β-DG ectodomain has been identified in a patient affected by muscle-eye-brain disease with multicystic leucodystrophy, suggesting that other mechanisms than hypoglycosylation of α-DG could be implicated in dystroglycanopathies. Herein, we have characterized the DG murine mutant counterpart by transfection in cellular systems and high-resolution microscopy. We observed that the mutation alters the DG processing leading to retention of its uncleaved precursor in the endoplasmic reticulum. Accordingly, small-angle X-ray scattering data, corroborated by biochemical and biophysical experiments, revealed that the mutation provokes an alteration in the β-DG ectodomain overall folding, resulting in disulfide-associated oligomerization. Our data provide the first evidence of a novel intracellular mechanism, featuring an anomalous endoplasmic reticulum-retention, underlying dystroglycanopathy.
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Affiliation(s)
- Giulia Signorino
- Istituto di Biochimica e Biochimica Clinica, Università Cattolica del Sacro Cuore, Roma, Italy
| | | | - Manuela Bozzi
- Istituto di Biochimica e Biochimica Clinica, Università Cattolica del Sacro Cuore, Roma, Italy.,Istituto di Chimica del Riconoscimento Molecolare - CNR c/o Istituto di Biochimica e Biochimica Clinica, Università Cattolica del Sacro Cuore, Roma, Italy
| | - Wolfgang Hübner
- Biomolecular Photonics, University of Bielefeld, Bielefeld, Germany
| | | | - Petr V Konarev
- A.V. Shubnikov Institute of Crystallography of Federal Scientific Research Centre "Crystallography and Photonics" of Russian Academy of Sciences, Leninsky prospect 59, Moscow, Russia
| | - Alberto Cassetta
- Istituto di Cristallografia - CNR, Trieste Outstation, Trieste, Italy
| | - Andrea Brancaccio
- Istituto di Chimica del Riconoscimento Molecolare - CNR c/o Istituto di Biochimica e Biochimica Clinica, Università Cattolica del Sacro Cuore, Roma, Italy.,School of Biochemistry, University of Bristol, Bristol, United Kingdom
| | - Francesca Sciandra
- Istituto di Chimica del Riconoscimento Molecolare - CNR c/o Istituto di Biochimica e Biochimica Clinica, Università Cattolica del Sacro Cuore, Roma, Italy
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16
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Covaceuszach S, Bozzi M, Bigotti MG, Sciandra F, Konarev PV, Brancaccio A, Cassetta A. The effect of the pathological V72I, D109N and T190M missense mutations on the molecular structure of α-dystroglycan. PLoS One 2017; 12:e0186110. [PMID: 29036200 PMCID: PMC5643065 DOI: 10.1371/journal.pone.0186110] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2017] [Accepted: 09/25/2017] [Indexed: 11/18/2022] Open
Abstract
Dystroglycan (DG) is a highly glycosylated protein complex that links the cytoskeleton with the extracellular matrix, mediating fundamental physiological functions such as mechanical stability of tissues, matrix organization and cell polarity. A crucial role in the glycosylation of the DG α subunit is played by its own N-terminal region that is required by the glycosyltransferase LARGE. Alteration in this O-glycosylation deeply impairs the high affinity binding to other extracellular matrix proteins such as laminins. Recently, three missense mutations in the gene encoding DG, mapped in the α-DG N-terminal region, were found to be responsible for hypoglycosylated states, causing congenital diseases of different severity referred as primary dystroglycanopaties.To gain insight on the molecular basis of these disorders, we investigated the crystallographic and solution structures of these pathological point mutants, namely V72I, D109N and T190M. Small Angle X-ray Scattering analysis reveals that these mutations affect the structures in solution, altering the distribution between compact and more elongated conformations. These results, supported by biochemical and biophysical assays, point to an altered structural flexibility of the mutant α-DG N-terminal region that may have repercussions on its interaction with LARGE and/or other DG-modifying enzymes, eventually reducing their catalytic efficiency.
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Affiliation(s)
| | - Manuela Bozzi
- Istituto di Biochimica e Biochimica Clinica, Università Cattolica del Sacro Cuore, Roma, Italy
- Istituto di Chimica del Riconoscimento Molecolare—CNR c/o Università Cattolica del Sacro Cuore, Roma, Italy
| | | | - Francesca Sciandra
- Istituto di Chimica del Riconoscimento Molecolare—CNR c/o Università Cattolica del Sacro Cuore, Roma, Italy
| | - Petr V. Konarev
- A.V. Shubnikov Institute of Crystallography of Federal Scientific Research Centre “Crystallography and Photonics” of Russian Academy of Sciences, Moscow, Russia
- National Research Centre “Kurchatov Institute”, Moscow, Russia
| | - Andrea Brancaccio
- Istituto di Chimica del Riconoscimento Molecolare—CNR c/o Università Cattolica del Sacro Cuore, Roma, Italy
- School of Biochemistry, University of Bristol, Bristol, United Kingdom
| | - Alberto Cassetta
- Istituto di Cristallografia–CNR, Trieste Outstation, Trieste, Italy
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Covaceuszach S, Bozzi M, Bigotti MG, Sciandra F, Konarev PV, Brancaccio A, Cassetta A. Structural flexibility of human α-dystroglycan. FEBS Open Bio 2017; 7:1064-1077. [PMID: 28781947 PMCID: PMC5537065 DOI: 10.1002/2211-5463.12259] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2017] [Accepted: 06/09/2017] [Indexed: 01/13/2023] Open
Abstract
Dystroglycan (DG), composed of α and β subunits, belongs to the dystrophin-associated glycoprotein complex. α-DG is an extracellular matrix protein that undergoes a complex post-translational glycosylation process. The bifunctional glycosyltransferase like-acetylglucosaminyltransferase (LARGE) plays a crucial role in the maturation of α-DG, enabling its binding to laminin. We have already structurally analyzed the N-terminal region of murine α-DG (α-DG-Nt) and of a pathological single point mutant that may affect recognition of LARGE, although the structural features of the potential interaction between LARGE and DG remain elusive. We now report on the crystal structure of the wild-type human α-DG-Nt that has allowed us to assess the reliability of our murine crystallographic structure as a α-DG-Nt general model. Moreover, we address for the first time both structures in solution. Interestingly, small-angle X-ray scattering (SAXS) reveals the existence of two main protein conformations ensembles. The predominant species is reminiscent of the crystal structure, while the less populated one assumes a more extended fold. A comparative analysis of the human and murine α-DG-Nt solution structures reveals that the two proteins share a common interdomain flexibility and population distribution of the two conformers. This is confirmed by the very similar stability displayed by the two orthologs as assessed by biochemical and biophysical experiments. These results highlight the need to take into account the molecular plasticity of α-DG-Nt in solution, as it can play an important role in the functional interactions with other binding partners.
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Affiliation(s)
| | - Manuela Bozzi
- Istituto di Biochimica e Biochimica ClinicaUniversità Cattolica del Sacro CuoreRomaItaly
- Istituto di Chimica del Riconoscimento MolecolareCNR c/o Università Cattolica del Sacro CuoreRomaItaly
| | | | - Francesca Sciandra
- Istituto di Chimica del Riconoscimento MolecolareCNR c/o Università Cattolica del Sacro CuoreRomaItaly
| | - Petr Valeryevich Konarev
- Shubnikov Institute of Crystallography of Federal Scientific Research Centre“Crystallography and Photonics” of Russian Academy of SciencesMoscowRussia
- National Research Centre “Kurchatov Institute”MoscowRussia
| | - Andrea Brancaccio
- Istituto di Chimica del Riconoscimento MolecolareCNR c/o Università Cattolica del Sacro CuoreRomaItaly
- School of BiochemistryUniversity of BristolUK
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Suratanee A, Plaimas K. Reverse Nearest Neighbor Search on a Protein-Protein Interaction Network to Infer Protein-Disease Associations. Bioinform Biol Insights 2017; 11:1177932217720405. [PMID: 28757797 PMCID: PMC5513527 DOI: 10.1177/1177932217720405] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2017] [Accepted: 06/18/2017] [Indexed: 12/17/2022] Open
Abstract
The associations between proteins and diseases are crucial information for investigating pathological mechanisms. However, the number of known and reliable protein-disease associations is quite small. In this study, an analysis framework to infer associations between proteins and diseases was developed based on a large data set of a human protein-protein interaction network integrating an effective network search, namely, the reverse k-nearest neighbor (RkNN) search. The RkNN search was used to identify an impact of a protein on other proteins. Then, associations between proteins and diseases were inferred statistically. The method using the RkNN search yielded a much higher precision than a random selection, standard nearest neighbor search, or when applying the method to a random protein-protein interaction network. All protein-disease pair candidates were verified by a literature search. Supporting evidence for 596 pairs was identified. In addition, cluster analysis of these candidates revealed 10 promising groups of diseases to be further investigated experimentally. This method can be used to identify novel associations to better understand complex relationships between proteins and diseases.
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Affiliation(s)
- Apichat Suratanee
- Department of Mathematics, Faculty of Applied Science, King Mongkut's University of Technology North Bangkok, Bangkok, Thailand
| | - Kitiporn Plaimas
- Advanced Virtual and Intelligent Computing (AVIC) Center, Department of Mathematics and Computer Science, Faculty of Science, Chulalongkorn University, Bangkok, Thailand
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Brancaccio A, Adams JC. An evaluation of the evolution of the gene structure of dystroglycan. BMC Res Notes 2017; 10:19. [PMID: 28057052 PMCID: PMC5216574 DOI: 10.1186/s13104-016-2322-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2016] [Accepted: 12/06/2016] [Indexed: 11/10/2022] Open
Abstract
Background Dystroglycan (DG) is an adhesion receptor complex composed of two non-covalently associated subunits, transcribed from a single gene. The extracellular α-DG is highly and heterogeneously glycosylated and binds with high affinity to laminins, and the transmembrane β-DG binds intracellular dystrophin. Multiple cellular functions have been proposed for DG, notwithstanding that its role in skeletal muscle appears central as demonstrated by both primary and secondary severe muscular dystrophic phenotypes collectively known as dystroglycanopathies. We recently analysed the molecular phylogeny of the DG core protein and identified the α/β interface, transmembrane and cytoplasmic domains of β-DG as the most conserved region. It was also identified that the IG2_MAT_NU region has been independently duplicated in multiple lineages. Results To understand the evolution of dystroglycan in more depth, we investigated dystroglycan gene structure in 35 species representative of the phyla in which dystroglycan has been identified (i.e., all metazoan phyla except Ctenophora). The gene structure of three exons and two introns is remarkably conserved. However, additional lineage-specific introns were identified, which interrupt the coding sequence at distinct points, were identified in multiple metazoan groups, most prominently in ecdysozoans. Conclusions A coding DNA sequence (CDS) intron that interrupts the encoding of the IG1 domain is universally conserved and this intron is longer in gnathostomes (jawed vertebrates) than in other metazoans. Lineage-specific gain of additional introns has occurred notably in ecdysozoans, where multiple introns interrupt the large 3′ exon. More limited intron gain has also occurred in placozoa, cnidarians, urochordates and the DG paralogues of lamprey and teleost fish. Electronic supplementary material The online version of this article (doi:10.1186/s13104-016-2322-x) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Andrea Brancaccio
- Istituto di Chimica del Riconoscimento Molecolare, CNR, Istituto di Biochimica e Biochimica Clinica, Università Cattolica del Sacro Cuore, L.go F. Vito 1, 00168, Rome, Italy. .,School of Biochemistry, University of Bristol, Biomedical Sciences Building, University Walk, Bristol, BS8 1TD, UK.
| | - Josephine C Adams
- School of Biochemistry, University of Bristol, Biomedical Sciences Building, University Walk, Bristol, BS8 1TD, UK
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Mechanistic aspects of the formation of α-dystroglycan and therapeutic research for the treatment of α-dystroglycanopathy: A review. Mol Aspects Med 2016; 51:115-24. [PMID: 27421908 DOI: 10.1016/j.mam.2016.07.003] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2016] [Revised: 07/07/2016] [Accepted: 07/08/2016] [Indexed: 02/08/2023]
Abstract
α-Dystroglycanopathy, an autosomal recessive disease, is associated with the development of a variety of diseases, including muscular dystrophy. In humans, α-dystroglycanopathy includes various types of congenital muscular dystrophy such as Fukuyama type congenital muscular dystrophy (FCMD), muscle eye brain disease (MEB), and the Walker Warburg syndrome (WWS), and types of limb girdle muscular dystrophy 2I (LGMD2I). α-Dystroglycanopathy share a common etiology, since it is invariably caused by gene mutations that are associated with the O-mannose glycosylation pathway of α-dystroglycan (α-DG). α-DG is a central member of the dystrophin glycoprotein complex (DGC) family in peripheral membranes, and the proper glycosylation of α-DG is essential for it to bind to extracellular matrix proteins, such as laminin, to cell components. The disruption of this ligand-binding is thought to result in damage to cell membrane integration, leading to the development of muscular dystrophy. Clinical manifestations of α-dystroglycanopathy frequently include mild to severe alterations in the central nervous system and optical manifestations in addition to muscular dystrophy. Eighteen causative genes for α-dystroglycanopathy have been identified to date, and it is likely that more will be reported in the near future. These findings have stimulated extensive and energetic investigations in this research field, and novel glycosylation pathways have been implicated in the process. At the same time, the use of gene therapy, antisense therapy, and enzymatic supplementation have been evaluated as therapeutic possibilities for some types of α-dystroglycanopathy. Here we review the molecular and clinical findings associated with α-dystroglycanopathy and the development of therapeutic approaches, by comparing the approaches with the development of Duchenne muscular dystrophy.
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21
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Praissman JL, Willer T, Sheikh MO, Toi A, Chitayat D, Lin YY, Lee H, Stalnaker SH, Wang S, Prabhakar PK, Nelson SF, Stemple DL, Moore SA, Moremen KW, Campbell KP, Wells L. The functional O-mannose glycan on α-dystroglycan contains a phospho-ribitol primed for matriglycan addition. eLife 2016; 5. [PMID: 27130732 PMCID: PMC4924997 DOI: 10.7554/elife.14473] [Citation(s) in RCA: 83] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2016] [Accepted: 04/28/2016] [Indexed: 12/24/2022] Open
Abstract
Multiple glycosyltransferases are essential for the proper modification of alpha-dystroglycan, as mutations in the encoding genes cause congenital/limb-girdle muscular dystrophies. Here we elucidate further the structure of an O-mannose-initiated glycan on alpha-dystroglycan that is required to generate its extracellular matrix-binding polysaccharide. This functional glycan contains a novel ribitol structure that links a phosphotrisaccharide to xylose. ISPD is a CDP-ribitol (ribose) pyrophosphorylase that generates the reduced sugar nucleotide for the insertion of ribitol in a phosphodiester linkage to the glycoprotein. TMEM5 is a UDP-xylosyl transferase that elaborates the structure. We demonstrate in a zebrafish model as well as in a human patient that defects in TMEM5 result in muscular dystrophy in combination with abnormal brain development. Thus, we propose a novel structure—a ribitol in a phosphodiester linkage—for the moiety on which TMEM5, B4GAT1, and LARGE act to generate the functional receptor for ECM proteins having LG domains. DOI:http://dx.doi.org/10.7554/eLife.14473.001
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Affiliation(s)
- Jeremy L Praissman
- Complex Carbohydrate Research Center, University of Georgia, Athens, United States
| | - Tobias Willer
- Department of Molecular Physiology and Biophysics, Carver College of Medicine, University of Iowa, Iowa City, United States.,Howard Hughes Medical Institute, University of Iowa, Iowa City, United States.,Department of Neurology, Carver College of Medicine, University of Iowa, Iowa City, United States.,Department of Internal Medicine, Carver College of Medicine, University of Iowa, Iowa City, United States
| | - M Osman Sheikh
- Complex Carbohydrate Research Center, University of Georgia, Athens, United States
| | - Ants Toi
- Department of Medical Imaging, Mount Sinai Hospital, Toronto, Canada
| | - David Chitayat
- Division of Clinical and Metabolic Genetics, The Hospital for Sick Children, University of Toronto, Toronto, Canada.,The Prenatal Diagnosis and Medical Genetics Program, Mount Sinai Hospital, Toronto, Canada.,Department of Obstetrics and Gynecology, University of Toronto, Toronto, Canada
| | - Yung-Yao Lin
- Blizard Institute, London, United Kingdom.,Barts and The London School of Medicine and Dentistry, Queen Mary University of London, London, United Kingdom.,Wellcome Trust Genome Campus, Wellcome Trust Sanger Institute, Hinxton, United Kingdom
| | - Hane Lee
- Department of Human Genetics, University of California, Los Angeles, Los Angeles, United States.,David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, United States.,Department of Pathology and Laboratory Medicine, University of California, Los Angeles, Los Angeles, United States
| | | | - Shuo Wang
- Complex Carbohydrate Research Center, University of Georgia, Athens, United States
| | | | - Stanley F Nelson
- Department of Human Genetics, University of California, Los Angeles, Los Angeles, United States.,David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, United States.,Department of Pathology and Laboratory Medicine, University of California, Los Angeles, Los Angeles, United States
| | - Derek L Stemple
- Wellcome Trust Genome Campus, Wellcome Trust Sanger Institute, Hinxton, United Kingdom
| | - Steven A Moore
- Department of Pathology, Carver College of Medicine, University of Iowa, Iowa City, United States
| | - Kelley W Moremen
- Complex Carbohydrate Research Center, University of Georgia, Athens, United States.,Department of Biochemistry and Molecular Biology, University of Georgia, Athens, United States
| | - Kevin P Campbell
- Department of Molecular Physiology and Biophysics, Carver College of Medicine, University of Iowa, Iowa City, United States.,Howard Hughes Medical Institute, University of Iowa, Iowa City, United States.,Department of Neurology, Carver College of Medicine, University of Iowa, Iowa City, United States.,Department of Internal Medicine, Carver College of Medicine, University of Iowa, Iowa City, United States
| | - Lance Wells
- Complex Carbohydrate Research Center, University of Georgia, Athens, United States.,Department of Biochemistry and Molecular Biology, University of Georgia, Athens, United States
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Endo Y, Dong M, Noguchi S, Ogawa M, Hayashi YK, Kuru S, Sugiyama K, Nagai S, Ozasa S, Nonaka I, Nishino I. Milder forms of muscular dystrophy associated with POMGNT2 mutations. NEUROLOGY-GENETICS 2015; 1:e33. [PMID: 27066570 PMCID: PMC4811383 DOI: 10.1212/nxg.0000000000000033] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/16/2015] [Accepted: 09/24/2015] [Indexed: 12/15/2022]
Abstract
Objective: To determine the genetic variants in patients with dystroglycanopathy (DGP) and assess the pathogenicity of these variants. Methods: A total of 20 patients with DGP were identified by immunohistochemistry or Western blot analysis. Whole-exome sequencing (WES) was performed using patient samples. The pathogenicity of the variants identified was evaluated on the basis of the phenotypic recovery in a knockout (KO) haploid human cell line by transfection with mutated POMGNT2 cDNA and on the basis of the in vitro enzymatic activity of mutated proteins. Results: WES identified homozygous and compound heterozygous missense variants in POMGNT2 in 3 patients with the milder limb-girdle muscular dystrophy (LGMD) and intellectual disability without brain malformation. The 2 identified variants were located in the putative glycosyltransferase domain of POMGNT2, which affected its enzymatic activity. Mutated POMGNT2 cDNAs failed to rescue the phenotype of POMGNT2-KO cells. Conclusions: Novel variants in POMGNT2 are associated with milder forms of LGMD. The findings of this study expand the clinical and pathologic spectrum of DGP associated with POMGNT2 variants from the severest Walker-Warburg syndrome to the mildest LGMD phenotypes. The simple method to verify pathogenesis of variants may allow researchers to evaluate any variants present in all of the known causative genes and the variants in novel candidate genes to detect DGPs, particularly without using patients' specimens.
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Affiliation(s)
- Yukari Endo
- Department of Neuromuscular Research (Y.E., M.D., S. Noguchi, M.O., Y.K.H., I. Nonaka, I. Nishino), National Institute of Neuroscience; and Department of Genome Medicine Development (Y.E., S. Noguchi, I. Nishino), Medical Genome Center, NCNP, Tokyo, Japan; Department of Neurology (M.D.), China-Japan Friendship Hospital, Beijing, China; Department of Pathophysiology (Y.K.H.), Tokyo Medical University; National Hospital Organization Suzuka National Hospital (S.K.), Mie, Japan; Department of Pediatrics (K.S.), Local Independent Administrative Institution, Mie Prefectural General Medical Center; Department of Child Neurology (S. Nagai), Shikoku Medical Center for Children and Adults, Kagawa, Japan; and Department of Pediatrics (S.O.), Kumamoto University, Kumamoto, Japan
| | - Mingrui Dong
- Department of Neuromuscular Research (Y.E., M.D., S. Noguchi, M.O., Y.K.H., I. Nonaka, I. Nishino), National Institute of Neuroscience; and Department of Genome Medicine Development (Y.E., S. Noguchi, I. Nishino), Medical Genome Center, NCNP, Tokyo, Japan; Department of Neurology (M.D.), China-Japan Friendship Hospital, Beijing, China; Department of Pathophysiology (Y.K.H.), Tokyo Medical University; National Hospital Organization Suzuka National Hospital (S.K.), Mie, Japan; Department of Pediatrics (K.S.), Local Independent Administrative Institution, Mie Prefectural General Medical Center; Department of Child Neurology (S. Nagai), Shikoku Medical Center for Children and Adults, Kagawa, Japan; and Department of Pediatrics (S.O.), Kumamoto University, Kumamoto, Japan
| | - Satoru Noguchi
- Department of Neuromuscular Research (Y.E., M.D., S. Noguchi, M.O., Y.K.H., I. Nonaka, I. Nishino), National Institute of Neuroscience; and Department of Genome Medicine Development (Y.E., S. Noguchi, I. Nishino), Medical Genome Center, NCNP, Tokyo, Japan; Department of Neurology (M.D.), China-Japan Friendship Hospital, Beijing, China; Department of Pathophysiology (Y.K.H.), Tokyo Medical University; National Hospital Organization Suzuka National Hospital (S.K.), Mie, Japan; Department of Pediatrics (K.S.), Local Independent Administrative Institution, Mie Prefectural General Medical Center; Department of Child Neurology (S. Nagai), Shikoku Medical Center for Children and Adults, Kagawa, Japan; and Department of Pediatrics (S.O.), Kumamoto University, Kumamoto, Japan
| | - Megumu Ogawa
- Department of Neuromuscular Research (Y.E., M.D., S. Noguchi, M.O., Y.K.H., I. Nonaka, I. Nishino), National Institute of Neuroscience; and Department of Genome Medicine Development (Y.E., S. Noguchi, I. Nishino), Medical Genome Center, NCNP, Tokyo, Japan; Department of Neurology (M.D.), China-Japan Friendship Hospital, Beijing, China; Department of Pathophysiology (Y.K.H.), Tokyo Medical University; National Hospital Organization Suzuka National Hospital (S.K.), Mie, Japan; Department of Pediatrics (K.S.), Local Independent Administrative Institution, Mie Prefectural General Medical Center; Department of Child Neurology (S. Nagai), Shikoku Medical Center for Children and Adults, Kagawa, Japan; and Department of Pediatrics (S.O.), Kumamoto University, Kumamoto, Japan
| | - Yukiko K Hayashi
- Department of Neuromuscular Research (Y.E., M.D., S. Noguchi, M.O., Y.K.H., I. Nonaka, I. Nishino), National Institute of Neuroscience; and Department of Genome Medicine Development (Y.E., S. Noguchi, I. Nishino), Medical Genome Center, NCNP, Tokyo, Japan; Department of Neurology (M.D.), China-Japan Friendship Hospital, Beijing, China; Department of Pathophysiology (Y.K.H.), Tokyo Medical University; National Hospital Organization Suzuka National Hospital (S.K.), Mie, Japan; Department of Pediatrics (K.S.), Local Independent Administrative Institution, Mie Prefectural General Medical Center; Department of Child Neurology (S. Nagai), Shikoku Medical Center for Children and Adults, Kagawa, Japan; and Department of Pediatrics (S.O.), Kumamoto University, Kumamoto, Japan
| | - Satoshi Kuru
- Department of Neuromuscular Research (Y.E., M.D., S. Noguchi, M.O., Y.K.H., I. Nonaka, I. Nishino), National Institute of Neuroscience; and Department of Genome Medicine Development (Y.E., S. Noguchi, I. Nishino), Medical Genome Center, NCNP, Tokyo, Japan; Department of Neurology (M.D.), China-Japan Friendship Hospital, Beijing, China; Department of Pathophysiology (Y.K.H.), Tokyo Medical University; National Hospital Organization Suzuka National Hospital (S.K.), Mie, Japan; Department of Pediatrics (K.S.), Local Independent Administrative Institution, Mie Prefectural General Medical Center; Department of Child Neurology (S. Nagai), Shikoku Medical Center for Children and Adults, Kagawa, Japan; and Department of Pediatrics (S.O.), Kumamoto University, Kumamoto, Japan
| | - Kenji Sugiyama
- Department of Neuromuscular Research (Y.E., M.D., S. Noguchi, M.O., Y.K.H., I. Nonaka, I. Nishino), National Institute of Neuroscience; and Department of Genome Medicine Development (Y.E., S. Noguchi, I. Nishino), Medical Genome Center, NCNP, Tokyo, Japan; Department of Neurology (M.D.), China-Japan Friendship Hospital, Beijing, China; Department of Pathophysiology (Y.K.H.), Tokyo Medical University; National Hospital Organization Suzuka National Hospital (S.K.), Mie, Japan; Department of Pediatrics (K.S.), Local Independent Administrative Institution, Mie Prefectural General Medical Center; Department of Child Neurology (S. Nagai), Shikoku Medical Center for Children and Adults, Kagawa, Japan; and Department of Pediatrics (S.O.), Kumamoto University, Kumamoto, Japan
| | - Shigehiro Nagai
- Department of Neuromuscular Research (Y.E., M.D., S. Noguchi, M.O., Y.K.H., I. Nonaka, I. Nishino), National Institute of Neuroscience; and Department of Genome Medicine Development (Y.E., S. Noguchi, I. Nishino), Medical Genome Center, NCNP, Tokyo, Japan; Department of Neurology (M.D.), China-Japan Friendship Hospital, Beijing, China; Department of Pathophysiology (Y.K.H.), Tokyo Medical University; National Hospital Organization Suzuka National Hospital (S.K.), Mie, Japan; Department of Pediatrics (K.S.), Local Independent Administrative Institution, Mie Prefectural General Medical Center; Department of Child Neurology (S. Nagai), Shikoku Medical Center for Children and Adults, Kagawa, Japan; and Department of Pediatrics (S.O.), Kumamoto University, Kumamoto, Japan
| | - Shiro Ozasa
- Department of Neuromuscular Research (Y.E., M.D., S. Noguchi, M.O., Y.K.H., I. Nonaka, I. Nishino), National Institute of Neuroscience; and Department of Genome Medicine Development (Y.E., S. Noguchi, I. Nishino), Medical Genome Center, NCNP, Tokyo, Japan; Department of Neurology (M.D.), China-Japan Friendship Hospital, Beijing, China; Department of Pathophysiology (Y.K.H.), Tokyo Medical University; National Hospital Organization Suzuka National Hospital (S.K.), Mie, Japan; Department of Pediatrics (K.S.), Local Independent Administrative Institution, Mie Prefectural General Medical Center; Department of Child Neurology (S. Nagai), Shikoku Medical Center for Children and Adults, Kagawa, Japan; and Department of Pediatrics (S.O.), Kumamoto University, Kumamoto, Japan
| | - Ikuya Nonaka
- Department of Neuromuscular Research (Y.E., M.D., S. Noguchi, M.O., Y.K.H., I. Nonaka, I. Nishino), National Institute of Neuroscience; and Department of Genome Medicine Development (Y.E., S. Noguchi, I. Nishino), Medical Genome Center, NCNP, Tokyo, Japan; Department of Neurology (M.D.), China-Japan Friendship Hospital, Beijing, China; Department of Pathophysiology (Y.K.H.), Tokyo Medical University; National Hospital Organization Suzuka National Hospital (S.K.), Mie, Japan; Department of Pediatrics (K.S.), Local Independent Administrative Institution, Mie Prefectural General Medical Center; Department of Child Neurology (S. Nagai), Shikoku Medical Center for Children and Adults, Kagawa, Japan; and Department of Pediatrics (S.O.), Kumamoto University, Kumamoto, Japan
| | - Ichizo Nishino
- Department of Neuromuscular Research (Y.E., M.D., S. Noguchi, M.O., Y.K.H., I. Nonaka, I. Nishino), National Institute of Neuroscience; and Department of Genome Medicine Development (Y.E., S. Noguchi, I. Nishino), Medical Genome Center, NCNP, Tokyo, Japan; Department of Neurology (M.D.), China-Japan Friendship Hospital, Beijing, China; Department of Pathophysiology (Y.K.H.), Tokyo Medical University; National Hospital Organization Suzuka National Hospital (S.K.), Mie, Japan; Department of Pediatrics (K.S.), Local Independent Administrative Institution, Mie Prefectural General Medical Center; Department of Child Neurology (S. Nagai), Shikoku Medical Center for Children and Adults, Kagawa, Japan; and Department of Pediatrics (S.O.), Kumamoto University, Kumamoto, Japan
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23
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Genetic Engineering of Dystroglycan in Animal Models of Muscular Dystrophy. BIOMED RESEARCH INTERNATIONAL 2015; 2015:635792. [PMID: 26380289 PMCID: PMC4561298 DOI: 10.1155/2015/635792] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/03/2014] [Accepted: 03/11/2015] [Indexed: 01/24/2023]
Abstract
In skeletal muscle, dystroglycan (DG) is the central component of the dystrophin-glycoprotein complex (DGC), a multimeric protein complex that ensures a strong mechanical link between the extracellular matrix and the cytoskeleton. Several muscular dystrophies arise from mutations hitting most of the components of the DGC. Mutations within the DG gene (DAG1) have been recently associated with two forms of muscular dystrophy, one displaying a milder and one a more severe phenotype. This review focuses specifically on the animal (murine and others) model systems that have been developed with the aim of directly engineering DAG1 in order to study the DG function in skeletal muscle as well as in other tissues. In the last years, conditional animal models overcoming the embryonic lethality of the DG knock-out in mouse have been generated and helped clarifying the crucial role of DG in skeletal muscle, while an increasing number of studies on knock-in mice are aimed at understanding the contribution of single amino acids to the stability of DG and to the possible development of muscular dystrophy.
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The Structure of the T190M Mutant of Murine α-Dystroglycan at High Resolution: Insight into the Molecular Basis of a Primary Dystroglycanopathy. PLoS One 2015; 10:e0124277. [PMID: 25932631 PMCID: PMC4416926 DOI: 10.1371/journal.pone.0124277] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2014] [Accepted: 03/12/2015] [Indexed: 11/19/2022] Open
Abstract
The severe dystroglycanopathy known as a form of limb-girdle muscular dystrophy (LGMD2P) is an autosomal recessive disease caused by the point mutation T192M in α-dystroglycan. Functional expression analysis in vitro and in vivo indicated that the mutation was responsible for a decrease in posttranslational glycosylation of dystroglycan, eventually interfering with its extracellular-matrix receptor function and laminin binding in skeletal muscle and brain. The X-ray crystal structure of the missense variant T190M of the murine N-terminal domain of α-dystroglycan (50-313) has been determined, and showed an overall topology (Ig-like domain followed by a basket-shaped domain reminiscent of the small subunit ribosomal protein S6) very similar to that of the wild-type structure. The crystallographic analysis revealed a change of the conformation assumed by the highly flexible loop encompassing residues 159-180. Moreover, a solvent shell reorganization around Met190 affects the interaction between the B1-B5 anti-parallel strands forming part of the floor of the basket-shaped domain, with likely repercussions on the folding stability of the protein domain(s) and on the overall molecular flexibility. Chemical denaturation and limited proteolysis experiments point to a decreased stability of the T190M variant with respect to its wild-type counterpart. This mutation may render the entire L-shaped protein architecture less flexible. The overall reduced flexibility and stability may affect the functional properties of α-dystroglycan via negatively influencing its binding behavior to factors needed for dystroglycan maturation, and may lay the molecular basis of the T190M-driven primary dystroglycanopathy.
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