DOCSLIB.ORG

Clinical, Pathological and Genetic Characteristics of Autosomal Dominant Inherited Dynamin 2 Centronuclear Myopathy

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text

Load more

MOLECULAR MEDICINE REPORTS 13: 4273-4278, 2016 Clinical, pathological and genetic characteristics of autosomal dominant inherited dynamin 2 centronuclear myopathy XINHONG LIU1,2, HUAMIN WU3, JIAN GONG4, TAO WANG2 and CHUANZHU YAN1 1Department of Neurology, Qilu Hospital of Shandong University, Jinan, Shandong 250012; Departments of 2Neurology, 3Radiology and 4Digestive System, Tai'an Central Hospital, Tai'an, Shandong 271000, P.R. China Received February 21, 2015; Accepted December 18, 2015 DOI: 10.3892/mmr.2016.5047 Abstract. The aim of the present study was to report on a the myotubularin 1 gene (MTM1) (2). A third gene, associ- family with pathologically and genetically diagnosed auto- ated with autosomal recessive inherited CNM, is bridging somal dominant inherited centronuclear myopathy (CNM). In integrator 1 (3). addition, this study aimed to investigate the clinical, patho- Previous studies on DNM2-associated CNM logical and molecular genetic characteristics of the disease. (DNM2 -CNM) cases have demonstrated that it can range from This pedigree was traced back three generations, four patients severe neonatal onset to mild adult onset, and the severity of underwent neurological examination, two patients underwent the clinical manifestations vary (4-7). The majority of patients muscle biopsy, and eight family members were subjected to exhibit distal or proximal muscle weakness as a first symptom, dynamin 2 (DNM2) gene mutation analysis. DNM2 mutations presenting as general muscle weakness, eyelid drooping, were detected in seven family members, of which four patients extraocular muscle paralysis, high arch palate, contracture of exhibited DNM2 mutation‑specific clinical and pathological the Achilles tendon, trismus, and reduction or lack of tendon features. Lower extremity weakness was the predominant reflexes, among which the weakness of the distal or lower limbs symptom of these patients, however, proximal and distal lower is most notable (4,8). Disease progression is predominantly extremity involvement was inconsistent. All patients exhibited slow and few patients develop independent‑walking difficulties marked systematic muscle atrophy and various degrees of in middle age or restrictive ventilatory disorders (9). Typical facial muscle involvement. The patients presented the typical pathological features of DNM2‑CNM are type I fiber predom- pathological changes of CNM, and their muscle tissues were inance and type I atrophy, increased proportions of radial heavily replaced by adipose tissue, with clustered distribution fibers and central nuclei in the sarcoplasmic reticulum (1). of muscle fibers as another notable feature. DNM2-CNM Approximately 100 DNM2-CNM families have exhibited patients of this pedigree exhibited heterogeneous clinical and 18 different DNM2 mutations (10). Patients with mutations pathological features, providing a basis for further molecular affecting the intermediate domains of DNM2 usually present genetic analysis. with relatively mild clinical features (5,11), while mutations impacting the pleckstrin protein family homology (PH) Introduction domain and GED structures result in more serious clinical manifestations (4). Centronuclear myopathies (CNMs) are a group of rare slowly To the best of our knowledge, this study is the first to progressive congenital myopathies, which are character- report on a Chinese family with pathologically and genetically ized by centronuclear dysplasia in muscle fibers. Autosomal confirmed DNM2‑associated autosomal dominant inherited dominant inherited mutations of the dynamin 2 (DNM2) CNM. This study aimed to investigate the clinical, patholog- gene are the cause of 50% of CNM cases (1). Clinical symp- ical and genetic characteristics of this disease, and contribute toms of DNM2-associated CNM are milder than those of to further molecular genetic studies of autosomal dominant X -linked recessive inheritedRETRACTED CNM caused by mutations in inherited CNM. Materials and methods Subjects. Four patients, two males and two females, belonging Correspondence to: Professor Chuanzhu Yan, Department of Neurology, Qilu Hospital of Shandong University, 107 Culture West to a family with three generations of autosomal dominant Road, Jinan, Shandong 250012, P.R. China inherited CNM (pedigree presented in Fig. 1), were investi- E -mail: [email protected] gated. The patients were recruited from the Qilu Hospital of Shandong University (Jinan, China) and presented muscle Key words: autosomal dominant inheritance, dynamin 2, centronuclear weakness. All patients underwent physical examination, myopathy genetic testing, and two of the patients further provided muscle biopsies. Detailed case history enquiries and clinical examina- tion were conducted by two neurologists. The present study 4274 LIU et al: CHARACTERISTICS OF DYNAMIN 2-CENTRONUCLEAR MYOPATHY Table I. Clinical patient data from d=four cases of dynamin 2-centronuclear myopathy. Variable I1 II2 II4 II5 Gender/age Female Male Female Male Age (years) 59 38 33 30 Onset Adolescence Adolescence Adolescence Adolescence Developmental delay Normal Normal Could walk at 2-years-old Unknown First symptom Lower extremity Lower extremity Lower extremity Lower extremity weakness weakness weakness weakness Muscle involvement Neck + - - - Upper limb Proximal 3 5 3-4 5 Distal 4 5 5 5 Lower limb Proximal 3 4-5 4 5 Distal 4 3 3 5 Limb-girdle muscular Upper limb 3-4 4 4 5 Lower limb 3-4 4 4 4 Facial muscle involvement + + + + Eyelid drooping + - - - Ophthalmoplegia ‑ ‑ ‑ ‑ High-vaulted arch - + - + Joint contractures - - - + Arched feet - - - - Curvature of spine - - - - Muscle atrophy + + + + Tendon reflexes + ‑ + ‑ + ‑ + ‑ Serum CK 126 Not tested Not tested Not tested EMG Myogenic damage Myogenic damage Not tested Not tested Dysphagia ‑ ‑ ‑ ‑ Breathing difficulty ‑ ‑ ‑ ‑ CK, creatine kinase; EMG, electromyography. -, negative; +, positive; + -, likely positive. Muscle strength grade: level 0, muscle paralysis, no contraction; level 1, slight contraction of the muscles, but no action; level 2, muscles only function when not subjected to excessive weight; level 3, muscles can carry out actions against gravity but not with added resistance; level 4, able to counteract some resistance against the muscle; level 5, normal muscle strength. was conducted in accordance with the declaration of Helsinki and with approval from the Ethics Committee of Shandong University (Jinan, China). Written informed consent was obtained from all participants.RETRACTED Pathological specimens. Muscle specimens of two patients were obtained from the left biceps by open biopsy. Fresh muscle samples were snap-frozen in liquid nitrogen-cooled isopentane (Sinopharm Chemical Reagent Co., Ltd., Beijing, China), and 8-µm tissue sections were cut using a Figure 1. Dynamin 2-associated autosomal dominant central nucleus myopathy cryo -ultramicrotome (Leica 1900; Leica Microsystems GmbH, family pedigree. Circle, female; square, male; black, affected; white, unaffected. Wetzlar, Germany) at ‑20 to ‑25˚C. Tissues were then stained with hematoxylin-eosin (H&E), modified Gomori's trichrome, NADH -tetrazolium reductase, cytochrome c oxidase, succinate routine use of dynamin-N, R, and C monoclonal antibody dehydrogenase, lactate dehydrogenase, periodic acid-Schiff, immunohistochemical staining in order to analyze dynamin and oil red O. Dystrophin staining was carried out with the protein expression levels in the sarcolemma using an optical MOLECULAR MEDICINE REPORTS 13: 4273-4278, 2016 4275 A B C D E F G H Figure 2. (A and B) I1, H&E staining, visible adipose tissue, muscle fibers distributed in clusters, fiber size is different in muscle tissue, the fibers are homo- geneously small, round and polygonal, with no obvious hyperplasia of the endomysium, >90% of the muscle fibers contain a central nucleus. (C) I1, NADH was used to distinguish between two types of fiber. (D‑I) II2, eldest son of I1 muscle pathology, (D and E) H&E staining, >90% of muscle fibers contain a central nucleus and exhibit visible adipose infiltration between the fibers. (F) NADH staining, typical appearance of fibrin observed. (G) Trophin staining demonstrates the membrane integrity with fat infiltration between the muscle fibers. (H) ATP staining demonstrated type I fiber predominated, however, a number of type II fibers were observed with normal ATP staining. microscope (Olympus BH-2; Olympus Corporation, Tokyo, involvement and various degrees of systematic muscle Japan). Remaining samples were stored at ‑80˚C until further atrophy. Symptoms are first identified at ~20 years of age, use. All specimens were reviewed and confirmed by two experi- while they were capable of taking care of themselves and enced clinical neurologists. living normal lives. The grandchildren of proband I1, III1 (13 years old), III2 (4 years old), III3 (4 years old) and III4 Gene sequencing analysis. Based on the DNM2 genome (5 years old), did not exhibit symptoms of muscle weakness, sequence, primers were designed to cover 22 exons, including and their sports activities were the same as healthy children alternate exons, exon 10b and exon 13b. DNM2 sequences of of the same age. However, III3 exhibited general features of eight family members were determined and compared with congenital muscular disease, including emaciation, narrow the human gene mutation database (http://www.hgmd.cf.ac. face and high-vaulted arch. Judging from the combined uk/ac/index.php) by Beijing ACCB Biotech, Ltd. (Beijing, inheritance mode and clinical
Recommended publications
  • Myotubular Myopathy Caused by Multiple Abnormal Splicing Variants in the MTM1 RNA in a Patient with a Mild Phenotype

    Myotubular Myopathy Caused by Multiple Abnormal Splicing Variants in the MTM1 RNA in a Patient with a Mild Phenotype

    European Journal of Human Genetics (2012) 20, 701–704 & 2012 Macmillan Publishers Limited All rights reserved 1018-4813/12 www.nature.com/ejhg SHORT REPORT Myotubular myopathy caused by multiple abnormal splicing variants in the MTM1 RNA in a patient with a mild phenotype Nasim Vasli1,2,3,4, Vincent Laugel5, Johann Bo¨hm1,2,3,4,Be´atrice Lannes6, Vale´rie Biancalana1,2,3,4,7and Jocelyn Laporte*,1,2,3,4 Mutations impacting on the splicing of pre-mRNA are one important cause of genetically inherited diseases. However, detection of splice mutations, that are mainly due to intronic variations, and characterization of their effects are usually not performed as a first approach during genetic diagnosis. X-linked recessive myotubular myopathy is a severe congenital myopathy due to mutations in the MTM1 gene encoding myotubularin. Here, we screened a male patient showing an unusually mild phenotype without respiratory distress by western blot with specific myotubularin antibodies and detected a strong reduction of the protein level.The disease was subsequently linked to a hemizygous point mutation affecting the acceptor splice site of exon 8 of MTM1, proven by protein, transcript and genomic DNA analysis. Detailed analysis of the MTM1 mRNA by RT-PCR, sequencing and quantitative PCR revealed multiple abnormal transcripts with retention of a truncated exon 8, and neighboring exons 7 and 9 but exclusion of several other exons, suggesting a complex effect of this mutation on the splicing of non-adjacent exons. We conclude that the analysis of RNA by RT-PCR and sequencing is an important step to characterize the precise impact of detected splice variants.
  • 2021 Code Changes Reference Guide

    2021 Code Changes Reference Guide

    Boston University Medical Group 2021 CPT Code Changes Reference Guide Page 1 of 51 Background Current Procedural Terminology (CPT) was created by the American Medical Association (AMA) in 1966. It is designed to be a means of effective and dependable communication among physicians, patients, and third-party payers. CPT provides a uniform coding scheme that accurately describes medical, surgical, and diagnostic services. CPT is used for public and private reimbursement systems; development of guidelines for medical care review; as a basis for local, regional, and national utilization comparisons; and medical education and research. CPT Category I codes describe procedures and services that are consistent with contemporary medical practice. Category I codes are five-digit numeric codes. CPT Category II codes facilitate data collection for certain services and test results that contribute to positive health outcomes and quality patient care. These codes are optional and used for performance management. They are alphanumeric five-digit codes with the alpha character F in the last position. CPT Category III codes represent emerging technologies. They are alphanumeric five-digit codes with the alpha character T in the last position. The CPT Editorial Panel, appointed by the AMA Board of Trustees, is responsible for maintaining and updating the CPT code set. Purpose The AMA makes annual updates to the CPT code set, effective January 1. These updates include deleted codes, revised codes, and new codes. It’s important for providers to understand the code changes and the impact those changes will have to systems, workflow, reimbursement, and RVUs. This document is meant to assist you with this by providing a summary of the changes; a detailed breakdown of this year’s CPT changes by specialty, and HCPCS Updates for your reference.
  • Lipid Phosphatases Identified by Screening a Mouse Phosphatase Shrna Library Regulate T-Cell Differentiation and Protein Kinase

    Lipid Phosphatases Identified by Screening a Mouse Phosphatase Shrna Library Regulate T-Cell Differentiation and Protein Kinase

    Lipid phosphatases identified by screening a mouse PNAS PLUS phosphatase shRNA library regulate T-cell differentiation and Protein kinase B AKT signaling Liying Guoa, Craig Martensb, Daniel Brunob, Stephen F. Porcellab, Hidehiro Yamanea, Stephane M. Caucheteuxa, Jinfang Zhuc, and William E. Paula,1 aCytokine Biology Unit, cMolecular and Cellular Immunoregulation Unit, Laboratory of Immunology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892; and bGenomics Unit, Research Technologies Section, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, MT 59840 Contributed by William E. Paul, March 27, 2013 (sent for review December 18, 2012) Screening a complete mouse phosphatase lentiviral shRNA library production (10, 11). Conversely, constitutive expression of active using high-throughput sequencing revealed several phosphatases AKT leads to increased proliferation and enhanced Th1/Th2 cy- that regulate CD4 T-cell differentiation. We concentrated on two lipid tokine production (12). phosphatases, the myotubularin-related protein (MTMR)9 and -7. The amount of PI[3,4,5]P3 and the level of AKT activation are Silencing MTMR9 by shRNA or siRNA resulted in enhanced T-helper tightly controlled by several mechanisms, including breakdown of (Th)1 differentiation and increased Th1 protein kinase B (PKB)/AKT PI[3,4,5]P3, down-regulation of the amount and activity of PI3K, phosphorylation while silencing MTMR7 caused increased Th2 and and the dephosphorylation of AKT (13). PTEN is a major negative Th17 differentiation and increased AKT phosphorylation in these regulator of PI[3,4,5]P3. It removes the 3-phosphate from the cells.
  • 1 Novel Expression Signatures Identified by Transcriptional Analysis

    1 Novel Expression Signatures Identified by Transcriptional Analysis

    ARD Online First, published on October 7, 2009 as 10.1136/ard.2009.108043 Ann Rheum Dis: first published as 10.1136/ard.2009.108043 on 7 October 2009. Downloaded from Novel expression signatures identified by transcriptional analysis of separated leukocyte subsets in SLE and vasculitis 1Paul A Lyons, 1Eoin F McKinney, 1Tim F Rayner, 1Alexander Hatton, 1Hayley B Woffendin, 1Maria Koukoulaki, 2Thomas C Freeman, 1David RW Jayne, 1Afzal N Chaudhry, and 1Kenneth GC Smith. 1Cambridge Institute for Medical Research and Department of Medicine, Addenbrooke’s Hospital, Hills Road, Cambridge, CB2 0XY, UK 2Roslin Institute, University of Edinburgh, Roslin, Midlothian, EH25 9PS, UK Correspondence should be addressed to Dr Paul Lyons or Prof Kenneth Smith, Department of Medicine, Cambridge Institute for Medical Research, Addenbrooke’s Hospital, Hills Road, Cambridge, CB2 0XY, UK. Telephone: +44 1223 762642, Fax: +44 1223 762640, E-mail: [email protected] or [email protected] Key words: Gene expression, autoimmune disease, SLE, vasculitis Word count: 2,906 The Corresponding Author has the right to grant on behalf of all authors and does grant on behalf of all authors, an exclusive licence (or non-exclusive for government employees) on a worldwide basis to the BMJ Publishing Group Ltd and its Licensees to permit this article (if accepted) to be published in Annals of the Rheumatic Diseases and any other BMJPGL products to exploit all subsidiary rights, as set out in their licence (http://ard.bmj.com/ifora/licence.pdf). http://ard.bmj.com/ on September 29, 2021 by guest. Protected copyright. 1 Copyright Article author (or their employer) 2009.
  • Genetic Testing Medical Policy – Genetics

    Genetic Testing Medical Policy – Genetics

    Genetic Testing Medical Policy – Genetics Please complete all appropriate questions fully. Suggested medical record documentation: • Current History & Physical • Progress Notes • Family Genetic History • Genetic Counseling Evaluation *Failure to include suggested medical record documentation may result in delay or possible denial of request. PATIENT INFORMATION Name: Member ID: Group ID: PROCEDURE INFORMATION Genetic Counseling performed: c Yes c No **Please check the requested analyte(s), identify number of units requested, and provide indication/rationale for testing. 81400 Molecular Pathology Level 1 Units _____ c ACADM (acyl-CoA dehydrogenase, C-4 to C-12 straight chain, MCAD) (e.g., medium chain acyl dehydrogenase deficiency), K304E variant _____ c ACE (angiotensin converting enzyme) (e.g., hereditary blood pressure regulation), insertion/deletion variant _____ c AGTR1 (angiotensin II receptor, type 1) (e.g., essential hypertension), 1166A>C variant _____ c BCKDHA (branched chain keto acid dehydrogenase E1, alpha polypeptide) (e.g., maple syrup urine disease, type 1A), Y438N variant _____ c CCR5 (chemokine C-C motif receptor 5) (e.g., HIV resistance), 32-bp deletion mutation/794 825del32 deletion _____ c CLRN1 (clarin 1) (e.g., Usher syndrome, type 3), N48K variant _____ c DPYD (dihydropyrimidine dehydrogenase) (e.g., 5-fluorouracil/5-FU and capecitabine drug metabolism), IVS14+1G>A variant _____ c F13B (coagulation factor XIII, B polypeptide) (e.g., hereditary hypercoagulability), V34L variant _____ c F2 (coagulation factor 2) (e.g.,
  • Live-Cell Imaging Rnai Screen Identifies PP2A–B55α and Importin-Β1 As Key Mitotic Exit Regulators in Human Cells

    Live-Cell Imaging Rnai Screen Identifies PP2A–B55α and Importin-Β1 As Key Mitotic Exit Regulators in Human Cells

    LETTERS Live-cell imaging RNAi screen identifies PP2A–B55α and importin-β1 as key mitotic exit regulators in human cells Michael H. A. Schmitz1,2,3, Michael Held1,2, Veerle Janssens4, James R. A. Hutchins5, Otto Hudecz6, Elitsa Ivanova4, Jozef Goris4, Laura Trinkle-Mulcahy7, Angus I. Lamond8, Ina Poser9, Anthony A. Hyman9, Karl Mechtler5,6, Jan-Michael Peters5 and Daniel W. Gerlich1,2,10 When vertebrate cells exit mitosis various cellular structures can contribute to Cdk1 substrate dephosphorylation during vertebrate are re-organized to build functional interphase cells1. This mitotic exit, whereas Ca2+-triggered mitotic exit in cytostatic-factor- depends on Cdk1 (cyclin dependent kinase 1) inactivation arrested egg extracts depends on calcineurin12,13. Early genetic studies in and subsequent dephosphorylation of its substrates2–4. Drosophila melanogaster 14,15 and Aspergillus nidulans16 reported defects Members of the protein phosphatase 1 and 2A (PP1 and in late mitosis of PP1 and PP2A mutants. However, the assays used in PP2A) families can dephosphorylate Cdk1 substrates in these studies were not specific for mitotic exit because they scored pro- biochemical extracts during mitotic exit5,6, but how this relates metaphase arrest or anaphase chromosome bridges, which can result to postmitotic reassembly of interphase structures in intact from defects in early mitosis. cells is not known. Here, we use a live-cell imaging assay and Intracellular targeting of Ser/Thr phosphatase complexes to specific RNAi knockdown to screen a genome-wide library of protein substrates is mediated by a diverse range of regulatory and targeting phosphatases for mitotic exit functions in human cells. We subunits that associate with a small group of catalytic subunits3,4,17.
  • Phosphatases Page 1

    Phosphatases Page 1

    Phosphatases esiRNA ID Gene Name Gene Description Ensembl ID HU-05948-1 ACP1 acid phosphatase 1, soluble ENSG00000143727 HU-01870-1 ACP2 acid phosphatase 2, lysosomal ENSG00000134575 HU-05292-1 ACP5 acid phosphatase 5, tartrate resistant ENSG00000102575 HU-02655-1 ACP6 acid phosphatase 6, lysophosphatidic ENSG00000162836 HU-13465-1 ACPL2 acid phosphatase-like 2 ENSG00000155893 HU-06716-1 ACPP acid phosphatase, prostate ENSG00000014257 HU-15218-1 ACPT acid phosphatase, testicular ENSG00000142513 HU-09496-1 ACYP1 acylphosphatase 1, erythrocyte (common) type ENSG00000119640 HU-04746-1 ALPL alkaline phosphatase, liver ENSG00000162551 HU-14729-1 ALPP alkaline phosphatase, placental ENSG00000163283 HU-14729-1 ALPP alkaline phosphatase, placental ENSG00000163283 HU-14729-1 ALPPL2 alkaline phosphatase, placental-like 2 ENSG00000163286 HU-07767-1 BPGM 2,3-bisphosphoglycerate mutase ENSG00000172331 HU-06476-1 BPNT1 3'(2'), 5'-bisphosphate nucleotidase 1 ENSG00000162813 HU-09086-1 CANT1 calcium activated nucleotidase 1 ENSG00000171302 HU-03115-1 CCDC155 coiled-coil domain containing 155 ENSG00000161609 HU-09022-1 CDC14A CDC14 cell division cycle 14 homolog A (S. cerevisiae) ENSG00000079335 HU-11533-1 CDC14B CDC14 cell division cycle 14 homolog B (S. cerevisiae) ENSG00000081377 HU-06323-1 CDC25A cell division cycle 25 homolog A (S. pombe) ENSG00000164045 HU-07288-1 CDC25B cell division cycle 25 homolog B (S. pombe) ENSG00000101224 HU-06033-1 CDKN3 cyclin-dependent kinase inhibitor 3 ENSG00000100526 HU-02274-1 CTDSP1 CTD (carboxy-terminal domain,
  • Centronuclear Myopathies Norma Romero, Marc Bitoun

    Centronuclear Myopathies Norma Romero, Marc Bitoun

    Centronuclear Myopathies Norma Romero, Marc Bitoun To cite this version: Norma Romero, Marc Bitoun. Centronuclear Myopathies. Seminars in Pediatric Neurology, WB Saunders, 2011, 18 (4), pp.250-256. 10.1016/j.spen.2011.10.006. hal-02451115 HAL Id: hal-02451115 https://hal.archives-ouvertes.fr/hal-02451115 Submitted on 23 Jan 2020 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. Centronuclear myopathies Norma Beatriz Romero and Marc Bitoun Norma Beatriz ROMERO, MD, PhD - Head of the Unit of Neuromuscular Morphology of the Institute of Myology - From the Institute of Myology, Inserm UMRS 974, CNRS UMR 7215 – UPMC-University Paris 6 UM74, GHU Pitié-Salpêtrière. - Mailing address: Institut de Myologie, Inserm UMR974, Groupe Hospitalier Universitaire Pitié-Salpêtrière, Batiment Risler 47, boulevard de l'Hôpital. F-75 651 Paris Cedex 13 - France Phone: +33 1 42 16 22 42; Fax: +33 1 42 16 22 40 E-mail: [email protected] Marc BITOUN, PhD - Investigator in the Inserm UMRS 974, CNRS UMR 7215, UPMC University Paris 6 - From the Institute of Myology, Inserm UMRS 974, CNRS UMR 7215 – UPMC-University Paris 6 UM74. - Mailing address: Institut de Myologie, Inserm UMR974, Groupe Hospitalier Universitaire Pitié-Salpêtrière, Batiment Babinski.
  • Genetic Investigations of Sporadic Inclusion Body Myositis and Myopathies with Structural Abnormalities and Protein Aggregates in Muscle

    Genetic Investigations of Sporadic Inclusion Body Myositis and Myopathies with Structural Abnormalities and Protein Aggregates in Muscle

    Genetic Investigations of Sporadic Inclusion Body Myositis and Myopathies with Structural Abnormalities and Protein Aggregates in Muscle Qiang Gang MRC Centre for Neuromuscular Diseases and UCL Institute of Neurology Supervised by Professor Henry Houlden, Dr Conceição Bettencourt and Professor Michael Hanna Thesis submitted for the degree of Doctor of Philosophy University College London 2016 1 Declaration I, Qiang Gang, confirm that the work presented in this thesis is my own. Where information has been derived from other sources, I confirm that this has been indicated in the thesis. Signature………………………………………………………… Date……………………………………………………………... 2 Abstract The application of whole-exome sequencing (WES) has not only dramatically accelerated the discovery of pathogenic genes of Mendelian diseases, but has also shown promising findings in complex diseases. This thesis focuses on exploring genetic risk factors for a large series of sporadic inclusion body myositis (sIBM) cases, and identifying disease-causing genes for several groups of patients with abnormal structure and/or protein aggregates in muscle. Both conventional and advanced techniques were applied. Based on the International IBM Genetics Consortium (IIBMGC), the largest sIBM cohort of blood and muscle tissue for DNA analysis was collected as the initial part of this thesis. Candidate gene studies were carried out and revealed a disease modifying effect of an intronic polymorphism in TOMM40, enhanced by the APOE ε3/ε3 genotype. Rare variants in SQSTM1 and VCP genes were identified in seven of 181 patients, indicating a mutational overlap with neurodegenerative diseases. Subsequently, a first whole-exome association study was performed on 181 sIBM patients and 510 controls. This reported statistical significance of several common variants located on chromosome 6p21, a region encompassing genes related to inflammation/infection.
  • Loss of Catalytically Inactive Lipid Phosphatase Myotubularin-Related Protein 12 Impairs Myotubularin Stability and Promotes Centronuclear Myopathy in Zebrafish

    Loss of Catalytically Inactive Lipid Phosphatase Myotubularin-Related Protein 12 Impairs Myotubularin Stability and Promotes Centronuclear Myopathy in Zebrafish

    Loss of Catalytically Inactive Lipid Phosphatase Myotubularin-related Protein 12 Impairs Myotubularin Stability and Promotes Centronuclear Myopathy in Zebrafish Vandana A. Gupta1, Karim Hnia2, Laura L. Smith1, Stacey R. Gundry1, Jessica E. McIntire1, Junko Shimazu1, Jessica R. Bass1, Ethan A. Talbot1, Leonela Amoasii2, Nathaniel E. Goldman1, Jocelyn Laporte2, Alan H. Beggs1* 1 Genomics Program and Division of Genetics, The Manton Center for Orphan Disease Research, Boston Children’s Hospital, Harvard Medical School, Boston, Massachusetts, United States of America, 2 Department of Translational Medicine and Neurogenetics, Institut de Ge´ne´tique et de Biologie Mole´culaire et Cellulaire, Inserm U964, CNRS UMR7104, Universite´ de Strasbourg, Colle`ge de France, Chaire de Ge´ne´tique Humaine, Illkirch, France Abstract X-linked myotubular myopathy (XLMTM) is a congenital disorder caused by mutations of the myotubularin gene, MTM1. Myotubularin belongs to a large family of conserved lipid phosphatases that include both catalytically active and inactive myotubularin-related proteins (i.e., ‘‘MTMRs’’). Biochemically, catalytically inactive MTMRs have been shown to form heteroligomers with active members within the myotubularin family through protein-protein interactions. However, the pathophysiological significance of catalytically inactive MTMRs remains unknown in muscle. By in vitro as well as in vivo studies, we have identified that catalytically inactive myotubularin-related protein 12 (MTMR12) binds to myotubularin in skeletal muscle. Knockdown of the mtmr12 gene in zebrafish resulted in skeletal muscle defects and impaired motor function. Analysis of mtmr12 morphant fish showed pathological changes with central nucleation, disorganized Triads, myofiber hypotrophy and whorled membrane structures similar to those seen in X-linked myotubular myopathy.
  • Lipid Phosphatases Identified by Screening a Mouse Phosphatase

    Lipid Phosphatases Identified by Screening a Mouse Phosphatase

    Lipid phosphatases identified by screening a mouse PNAS PLUS phosphatase shRNA library regulate T-cell differentiation and Protein kinase B AKT signaling Liying Guoa, Craig Martensb, Daniel Brunob, Stephen F. Porcellab, Hidehiro Yamanea, Stephane M. Caucheteuxa, Jinfang Zhuc, and William E. Paula,1 aCytokine Biology Unit, cMolecular and Cellular Immunoregulation Unit, Laboratory of Immunology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892; and bGenomics Unit, Research Technologies Section, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, MT 59840 Contributed by William E. Paul, March 27, 2013 (sent for review December 18, 2012) Screening a complete mouse phosphatase lentiviral shRNA library production (10, 11). Conversely, constitutive expression of active using high-throughput sequencing revealed several phosphatases AKT leads to increased proliferation and enhanced Th1/Th2 cy- that regulate CD4 T-cell differentiation. We concentrated on two lipid tokine production (12). phosphatases, the myotubularin-related protein (MTMR)9 and -7. The amount of PI[3,4,5]P3 and the level of AKT activation are Silencing MTMR9 by shRNA or siRNA resulted in enhanced T-helper tightly controlled by several mechanisms, including breakdown of (Th)1 differentiation and increased Th1 protein kinase B (PKB)/AKT PI[3,4,5]P3, down-regulation of the amount and activity of PI3K, phosphorylation while silencing MTMR7 caused increased Th2 and and the dephosphorylation of AKT (13). PTEN is a major negative Th17 differentiation and increased AKT phosphorylation in these regulator of PI[3,4,5]P3. It removes the 3-phosphate from the cells.
  • Supplemental Material

    Supplemental Material

    Supplemental Figure 1. Heat map comparing expression of individual genes and significant modules. Expression values were normalized by gene and mean normalized expression values for each experimental animal (Control or SIVE) were calculated for the set of filtered significant modules. Compared with individual gene expression, average module expression yields a more homogeneous, though less intense, differentiation between uninfected and SIVE animals. Figure was generated by TMeV software [http://www.tm4.org/mev.html] . Supplemental Figure 2. Multiple chemokine receptors are expressed on differentiated SK-N-MC cells. Cells were differentiated for 4 days with retinoic acid prior to FACS analysis for chemokine receptors CCR2 (ligands: CCL2, CCL8), CCR3 (CCL8), CXCR1 (IL8), CXCR2 (IL8), CXCR3 (CXCL10), and high- and low-affinity NGF receptors. Table S1. Summary of rhesus monkeys - treatment history CONTROL Monkey Age (years) Sex anti-CD8 treatment Days infected Brain Viral Load 298 5 Male No NA NA 331 6 Male No NA NA 332 5 Male No NA NA 349 3 Male No NA NA 357 4 Male No NA NA 359 8 Male No NA NA 382 5 Male No NA NA 392 4 Male Yes NA NA 393 3 Male Yes NA NA SIVE 289 6 Male Yes 72 5.41 321 6 Male Yes 108 5.77 323 6 Male Yes 93 6.68 328 6 Male Yes 79 6.20 383 5 Male No 132 6.06 417 2 Male No 56 5.89 418 5 Male No 82 6.76 427 4 Male No 104 6.63 494 5 Male No 105 5.96 Monkeys used in this study.