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Chen YC, Auer-Grumbach M, Matsukawa S, Zitzelsberger M, Themistocleous AC, Strom TM, Samara C, Moore AW, Cho LTY, Young GT, Weiss C, Schabhüttl M, Stucka R, Schmid AB, Parman Y, Graul-Neumann L, Heinritz W, Passarge E, Watson RM, Hertz JM, Moog U, Baumgartner M, Valente EM, Pereira D, Restrepo CM, Katona I, Dusl M, Stendel C, Wieland T, Stafford F, Reimann F, von Au K, Finke C, Willems PJ, Nahorski MS, Shaikh SS, Carvalho OP, Nicholas AK, Karbani G, McAleer MA, Cilio MR, McHugh JC, Murphy SM, Irvine AD, Jensen UB, Windhager R, Weis J, Bergmann C, Rautenstrauss B, Baets J, De Jonghe P, Reilly MM, Kropatsch R, Kurth I, Chrast R, Michiue T, Bennett DLH, Woods CG, Senderek J. Transcriptional regulator PRDM12 is essential for human pain perception. Nat Genet 2015; 47:803-8. [PMID: 26005867 DOI: 10.1038/ng.3308] [Citation(s) in RCA: 110] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2014] [Accepted: 04/27/2015] [Indexed: 12/12/2022]
Abstract
Pain perception has evolved as a warning mechanism to alert organisms to tissue damage and dangerous environments. In humans, however, undesirable, excessive or chronic pain is a common and major societal burden for which available medical treatments are currently suboptimal. New therapeutic options have recently been derived from studies of individuals with congenital insensitivity to pain (CIP). Here we identified 10 different homozygous mutations in PRDM12 (encoding PRDI-BF1 and RIZ homology domain-containing protein 12) in subjects with CIP from 11 families. Prdm proteins are a family of epigenetic regulators that control neural specification and neurogenesis. We determined that Prdm12 is expressed in nociceptors and their progenitors and participates in the development of sensory neurons in Xenopus embryos. Moreover, CIP-associated mutants abrogate the histone-modifying potential associated with wild-type Prdm12. Prdm12 emerges as a key factor in the orchestration of sensory neurogenesis and may hold promise as a target for new pain therapeutics.
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Affiliation(s)
- Ya-Chun Chen
- 1] Department of Medical Genetics, University of Cambridge, Cambridge, UK. [2] Cambridge Institute for Medical Research, University of Cambridge, Cambridge, UK
| | | | - Shinya Matsukawa
- Department of Life Sciences, Graduate School of Arts and Sciences, University of Tokyo, Tokyo, Japan
| | | | - Andreas C Themistocleous
- 1] Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, UK. [2] Brain Function Research Group, School of Physiology, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
| | - Tim M Strom
- 1] Institute of Human Genetics, Helmholtz Zentrum München, Neuherberg, Germany. [2] Institute of Human Genetics, Technische Universität München, Munich, Germany
| | - Chrysanthi Samara
- Department of Medical Genetics, University of Lausanne, Lausanne, Switzerland
| | - Adrian W Moore
- Disease Mechanism Research Core, RIKEN Brain Science Institute, Saitama, Japan
| | | | | | - Caecilia Weiss
- Friedrich-Baur-Institute, Ludwig Maximilians University Munich, Munich, Germany
| | - Maria Schabhüttl
- Department of Orthopaedics, Medical University Vienna, Vienna, Austria
| | - Rolf Stucka
- Friedrich-Baur-Institute, Ludwig Maximilians University Munich, Munich, Germany
| | - Annina B Schmid
- 1] Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, UK. [2] School of Health and Rehabilitation Sciences, The University of Queensland, St. Lucia, Australia
| | - Yesim Parman
- Department of Neurology, Istanbul University, Istanbul, Turkey
| | - Luitgard Graul-Neumann
- Ambulantes Gesundheitszentrum der Charité Campus Virchow (Humangenetik), Universitätsmedizin Berlin, Berlin, Germany
| | - Wolfram Heinritz
- 1] Praxis für Humangenetik Cottbus, Cottbus, Germany. [2] Institut für Humangenetik, Universitätsklinikum Leipzig, Leipzig, Germany
| | - Eberhard Passarge
- 1] Institut für Humangenetik, Universitätsklinikum Leipzig, Leipzig, Germany. [2] Institut für Humangenetik, Universitätsklinikum Essen, Essen, Germany
| | - Rosemarie M Watson
- Department of Dermatology, Our Lady's Children's Hospital, Dublin, Ireland
| | - Jens Michael Hertz
- Department of Clinical Genetics, Odense University Hospital, Odense, Denmark
| | - Ute Moog
- Institute of Human Genetics, Heidelberg University, Heidelberg, Germany
| | - Manuela Baumgartner
- Neuropädiatrische Ambulanz, Krankenhaus der Barmherzigen Schwestern Linz, Linz, Austria
| | - Enza Maria Valente
- Neurogenetics Unit, Casa Sollievo della Sofferenza, San Giovanni Rotondo, Italy
| | - Diego Pereira
- Departamento de Cirugía Plástica, Hospital Infantil Universitario de San José, Bogotá, Colombia
| | | | - Istvan Katona
- Institut für Neuropathologie, Uniklinik RWTH Aachen, Aachen, Germany
| | - Marina Dusl
- Friedrich-Baur-Institute, Ludwig Maximilians University Munich, Munich, Germany
| | - Claudia Stendel
- 1] Friedrich-Baur-Institute, Ludwig Maximilians University Munich, Munich, Germany. [2] German Center for Neurodegenerative Diseases (DZNE), Munich, Germany
| | - Thomas Wieland
- Institute of Human Genetics, Helmholtz Zentrum München, Neuherberg, Germany
| | - Fay Stafford
- 1] Department of Medical Genetics, University of Cambridge, Cambridge, UK. [2] Cambridge Institute for Medical Research, University of Cambridge, Cambridge, UK
| | - Frank Reimann
- Department of Clinical Biochemistry, University of Cambridge, Cambridge, UK
| | - Katja von Au
- SPZ Neuropädiatrie Charité, Universitätsmedizin Berlin, Berlin, Germany
| | - Christian Finke
- CharitéCentrum für Zahn-, Mund- und Kieferheilkunde, Arbeitsbereich Kinderzahnmedizin, Universitätsmedizin Berlin, Berlin, Germany
| | | | - Michael S Nahorski
- 1] Department of Medical Genetics, University of Cambridge, Cambridge, UK. [2] Cambridge Institute for Medical Research, University of Cambridge, Cambridge, UK
| | - Samiha S Shaikh
- 1] Department of Medical Genetics, University of Cambridge, Cambridge, UK. [2] Cambridge Institute for Medical Research, University of Cambridge, Cambridge, UK
| | - Ofélia P Carvalho
- 1] Department of Medical Genetics, University of Cambridge, Cambridge, UK. [2] Cambridge Institute for Medical Research, University of Cambridge, Cambridge, UK
| | - Adeline K Nicholas
- Cambridge Institute for Medical Research, University of Cambridge, Cambridge, UK
| | - Gulshan Karbani
- Yorkshire Regional Genetics Service, Chapel Allerton Hospital, Leeds, UK
| | - Maeve A McAleer
- Department of Dermatology, Our Lady's Children's Hospital, Dublin, Ireland
| | - Maria Roberta Cilio
- 1] Department of Neurology, University of California San Francisco, San Francisco, California, USA. [2] Department of Neuroscience, Bambino Gesù Children's Hospital and Research Institute, Rome, Italy
| | - John C McHugh
- Department of Neurology and Neurophysiology, Our Lady's Children's Hospital, Dublin, Ireland
| | - Sinead M Murphy
- 1] Department of Neurology, Adelaide &Meath Hospital, Dublin, Ireland. [2] Academic Unit of Neurology, Trinity College, Dublin, Ireland
| | - Alan D Irvine
- 1] Department of Dermatology, Our Lady's Children's Hospital, Dublin, Ireland. [2] Clinical Medicine, Trinity College, Dublin, Ireland
| | - Uffe Birk Jensen
- Department of Clinical Genetics, Aarhus University Hospital, Aarhus, Denmark
| | | | - Joachim Weis
- Institut für Neuropathologie, Uniklinik RWTH Aachen, Aachen, Germany
| | - Carsten Bergmann
- 1] Center for Human Genetics, Bioscientia, Ingelheim, Germany. [2] Department of Medicine, Renal Division, Freiburg University Medical Center, Freiburg, Germany. [3] Center for Clinical Research, Freiburg University Medical Center, Freiburg, Germany
| | - Bernd Rautenstrauss
- 1] Friedrich-Baur-Institute, Ludwig Maximilians University Munich, Munich, Germany. [2] Medizinisch Genetisches Zentrum, Munich, Germany
| | - Jonathan Baets
- 1] Neurogenetics Group, VIB Department of Molecular Genetics, University of Antwerp, Antwerp, Belgium. [2] Laboratory of Neurogenetics, Institute Born-Bunge, University of Antwerp, Antwerp, Belgium. [3] Department of Neurology, Antwerp University Hospital, Antwerp, Belgium
| | - Peter De Jonghe
- 1] Neurogenetics Group, VIB Department of Molecular Genetics, University of Antwerp, Antwerp, Belgium. [2] Laboratory of Neurogenetics, Institute Born-Bunge, University of Antwerp, Antwerp, Belgium. [3] Department of Neurology, Antwerp University Hospital, Antwerp, Belgium
| | - Mary M Reilly
- MRC Centre for Neuromuscular Diseases, UCL Institute of Neurology, National Hospital for Neurology, London, UK
| | - Regina Kropatsch
- Department of Human Genetics, Ruhr-University Bochum, Bochum, Germany
| | - Ingo Kurth
- Institute of Human Genetics, Jena University Hospital, Jena, Germany
| | - Roman Chrast
- 1] Institute of Human Genetics, Technische Universität München, Munich, Germany. [2] Department of Neuroscience, Karolinska Institutet, Stockholm, Sweden. [3] Department of Clinical Neuroscience, Karolinska Institutet, Stockholm, Sweden
| | - Tatsuo Michiue
- Department of Life Sciences, Graduate School of Arts and Sciences, University of Tokyo, Tokyo, Japan
| | - David L H Bennett
- Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, UK
| | - C Geoffrey Woods
- 1] Department of Medical Genetics, University of Cambridge, Cambridge, UK. [2] Cambridge Institute for Medical Research, University of Cambridge, Cambridge, UK
| | - Jan Senderek
- Friedrich-Baur-Institute, Ludwig Maximilians University Munich, Munich, Germany
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52
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Bartesaghi L, Arnaud Gouttenoire E, Prunotto A, Médard JJ, Bergmann S, Chrast R. Sox4 participates in the modulation of Schwann cell myelination. Eur J Neurosci 2015; 42:1788-96. [PMID: 25899854 DOI: 10.1111/ejn.12929] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2015] [Revised: 03/20/2015] [Accepted: 04/20/2015] [Indexed: 11/26/2022]
Abstract
In order to identify new regulators of Schwann cell myelination potentially playing a role in peripheral nervous system (PNS) pathologies, we analysed gene expression profiling data from three mouse models of demyelinating neuropathies and from the developing PNS. This analysis revealed that Sox4, which encodes a member of the Sry-related high-mobility group box protein family, was consistently upregulated in all three analysed models of neuropathy. Moreover, Sox4 showed a peak in its expression during development that corresponded with the onset of myelination. To gain further insights into the role of Sox4 in PNS development, we generated a transgenic mouse that specifically overexpresses Sox4 in Schwann cells. Sox4 overexpression led to a temporary delay in PNS myelination without affecting axonal sorting. Importantly, we observed that, whereas Sox4 mRNA could be efficiently overexpressed, Sox4 protein expression in Schwann cells was strictly regulated. Finally, our data showed that enforced expression of Sox4 in the mouse model for Charcot-Marie-Tooth 4C aggravated its neuropathic phenotype. Together, these observations reveal that Sox4 contributes to the regulation of Schwann cell myelination, and also indicates its involvement in the pathophysiology of peripheral neuropathies.
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Affiliation(s)
- Luca Bartesaghi
- Department of Medical Genetics, University of Lausanne, Lausanne, Switzerland.,Department of Neuroscience and Department of Clinical Neuroscience, Karolinska Institutet, Retzius väg 8, 171 77, Stockholm, Sweden
| | | | - Andrea Prunotto
- Department of Medical Genetics, University of Lausanne, Lausanne, Switzerland.,Swiss Institute of Bioinformatics, University of Lausanne, Lausanne, Switzerland
| | - Jean-Jacques Médard
- Department of Medical Genetics, University of Lausanne, Lausanne, Switzerland
| | - Sven Bergmann
- Department of Medical Genetics, University of Lausanne, Lausanne, Switzerland.,Swiss Institute of Bioinformatics, University of Lausanne, Lausanne, Switzerland
| | - Roman Chrast
- Department of Medical Genetics, University of Lausanne, Lausanne, Switzerland.,Department of Neuroscience and Department of Clinical Neuroscience, Karolinska Institutet, Retzius väg 8, 171 77, Stockholm, Sweden
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53
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Barneo-Muñoz M, Juárez P, Civera-Tregón A, Yndriago L, Pla-Martin D, Zenker J, Cuevas-Martín C, Estela A, Sánchez-Aragó M, Forteza-Vila J, Cuezva JM, Chrast R, Palau F. Lack of GDAP1 induces neuronal calcium and mitochondrial defects in a knockout mouse model of charcot-marie-tooth neuropathy. PLoS Genet 2015; 11:e1005115. [PMID: 25860513 PMCID: PMC4393229 DOI: 10.1371/journal.pgen.1005115] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2014] [Accepted: 03/03/2015] [Indexed: 12/20/2022] Open
Abstract
Mutations in GDAP1, which encodes protein located in the mitochondrial outer membrane, cause axonal recessive (AR-CMT2), axonal dominant (CMT2K) and demyelinating recessive (CMT4A) forms of Charcot-Marie-Tooth (CMT) neuropathy. Loss of function recessive mutations in GDAP1 are associated with decreased mitochondrial fission activity, while dominant mutations result in impairment of mitochondrial fusion with increased production of reactive oxygen species and susceptibility to apoptotic stimuli. GDAP1 silencing in vitro reduces Ca2+ inflow through store-operated Ca2+ entry (SOCE) upon mobilization of endoplasmic reticulum (ER) Ca2+, likely in association with an abnormal distribution of the mitochondrial network. To investigate the functional consequences of lack of GDAP1 in vivo, we generated a Gdap1 knockout mouse. The affected animals presented abnormal motor behavior starting at the age of 3 months. Electrophysiological and biochemical studies confirmed the axonal nature of the neuropathy whereas histopathological studies over time showed progressive loss of motor neurons (MNs) in the anterior horn of the spinal cord and defects in neuromuscular junctions. Analyses of cultured embryonic MNs and adult dorsal root ganglia neurons from affected animals demonstrated large and defective mitochondria, changes in the ER cisternae, reduced acetylation of cytoskeletal α-tubulin and increased autophagy vesicles. Importantly, MNs showed reduced cytosolic calcium and SOCE response. The development and characterization of the GDAP1 neuropathy mice model thus revealed that some of the pathophysiological changes present in axonal recessive form of the GDAP1-related CMT might be the consequence of changes in the mitochondrial network biology and mitochondria-endoplasmic reticulum interaction leading to abnormalities in calcium homeostasis.
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Affiliation(s)
- Manuela Barneo-Muñoz
- Program in Rare and Genetic Diseases and IBV/CSIC Associated Unit, Centro de Investigación Príncipe Felipe, Valencia, Spain
- CIBER de Enfermedades Raras (CIBERER), ISCIII, Valencia and Madrid, Spain
| | - Paula Juárez
- Program in Rare and Genetic Diseases and IBV/CSIC Associated Unit, Centro de Investigación Príncipe Felipe, Valencia, Spain
- CIBER de Enfermedades Raras (CIBERER), ISCIII, Valencia and Madrid, Spain
| | - Azahara Civera-Tregón
- Program in Rare and Genetic Diseases and IBV/CSIC Associated Unit, Centro de Investigación Príncipe Felipe, Valencia, Spain
| | - Laura Yndriago
- Program in Rare and Genetic Diseases and IBV/CSIC Associated Unit, Centro de Investigación Príncipe Felipe, Valencia, Spain
| | - David Pla-Martin
- Program in Rare and Genetic Diseases and IBV/CSIC Associated Unit, Centro de Investigación Príncipe Felipe, Valencia, Spain
- CIBER de Enfermedades Raras (CIBERER), ISCIII, Valencia and Madrid, Spain
| | - Jennifer Zenker
- Department of Medical Genetics, University of Lausanne, Lausanne, Switzerland
| | - Carmen Cuevas-Martín
- CIBER de Enfermedades Raras (CIBERER), ISCIII, Valencia and Madrid, Spain
- Centro de Biología Molecular Severo Ochoa, UAM-CSIC, Madrid, Spain
- Instituto de Investigación Hospital 12 de Octubre, Universidad Autónoma de Madrid, Madrid, Spain
| | - Anna Estela
- Program in Rare and Genetic Diseases and IBV/CSIC Associated Unit, Centro de Investigación Príncipe Felipe, Valencia, Spain
- CIBER de Enfermedades Raras (CIBERER), ISCIII, Valencia and Madrid, Spain
| | - María Sánchez-Aragó
- CIBER de Enfermedades Raras (CIBERER), ISCIII, Valencia and Madrid, Spain
- Centro de Biología Molecular Severo Ochoa, UAM-CSIC, Madrid, Spain
- Instituto de Investigación Hospital 12 de Octubre, Universidad Autónoma de Madrid, Madrid, Spain
| | - Jerónimo Forteza-Vila
- Program in Rare and Genetic Diseases and IBV/CSIC Associated Unit, Centro de Investigación Príncipe Felipe, Valencia, Spain
- Instituto Valenciano de Patología, Catholic University of Valencia, Valencia, Spain
| | - José M. Cuezva
- CIBER de Enfermedades Raras (CIBERER), ISCIII, Valencia and Madrid, Spain
- Centro de Biología Molecular Severo Ochoa, UAM-CSIC, Madrid, Spain
- Instituto de Investigación Hospital 12 de Octubre, Universidad Autónoma de Madrid, Madrid, Spain
| | - Roman Chrast
- Department of Medical Genetics, University of Lausanne, Lausanne, Switzerland
- Department of Neuroscience and Department of Clinical Neuroscience, Karolinska Institutet, Stockholm, Sweden
| | - Francesc Palau
- Program in Rare and Genetic Diseases and IBV/CSIC Associated Unit, Centro de Investigación Príncipe Felipe, Valencia, Spain
- CIBER de Enfermedades Raras (CIBERER), ISCIII, Valencia and Madrid, Spain
- University of Castilla-La Mancha School of Medicine at Ciudad Real, Ciudad Real, Spain
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54
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Filant J, Spencer TE. Uterine glands: biological roles in conceptus implantation, uterine receptivity and decidualization. THE INTERNATIONAL JOURNAL OF DEVELOPMENTAL BIOLOGY 2015; 58:107-16. [PMID: 25023676 DOI: 10.1387/ijdb.130344ts] [Citation(s) in RCA: 99] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
All mammalian uteri contain glands in the endometrium that synthesize or transport and secrete substances essential for survival and development of the conceptus (embryo/fetus and associated extraembryonic membranes). This review summarizes information related to the biological roles of uterine glands and their secretions in uterine receptivity, blastocyst/conceptus survival and implantation, and stromal cell decidualization. Studies with the ovine uterine gland knockout (UGKO) model support a primary role for uterine glands and, by inference, their secretions present in uterine luminal fluid histrotroph for conceptus survival and development. In rodents, studies with mutant and progesterone-induced UGKO mice found that uterine glands and their secretions are unequivocally required for establishment of uterine receptivity and blastocyst implantation and also may influence blastocyst trophectoderm activation and stromal cell decidualization in the uterus. Similarly in humans, histotroph from uterine glands appears critical for blastocyst implantation, uterine receptivity, and conceptus nutrition during the first trimester and uterine glands likely have a role in stromal cell decidualization. An increased understanding of uterine gland biology is important for diagnosis, prevention and treatment of fertility problems, particularly infertility and recurrent pregnancy loss, in domestic animals and humans.
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Affiliation(s)
- Justyna Filant
- Department of Animal Sciences and Center for Reproductive Biology, Washington State University, Pullman, WA, USA.
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55
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Brewer MH, Ma KH, Beecham GW, Gopinath C, Baas F, Choi BO, Reilly MM, Shy ME, Züchner S, Svaren J, Antonellis A. Haplotype-specific modulation of a SOX10/CREB response element at the Charcot-Marie-Tooth disease type 4C locus SH3TC2. Hum Mol Genet 2014; 23:5171-87. [PMID: 24833716 PMCID: PMC4168306 DOI: 10.1093/hmg/ddu240] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2014] [Revised: 05/01/2014] [Accepted: 05/12/2014] [Indexed: 12/22/2022] Open
Abstract
Loss-of-function mutations in the Src homology 3 (SH3) domain and tetratricopeptide repeats 2 (SH3TC2) gene cause autosomal recessive demyelinating Charcot-Marie-Tooth neuropathy. The SH3TC2 protein has been implicated in promyelination signaling through axonal neuregulin-1 and the ERBB2 Schwann cell receptor. However, little is known about the transcriptional regulation of the SH3TC2 gene. We performed computational and functional analyses that revealed two cis-acting regulatory elements at SH3TC2-one at the promoter and one ∼150 kb downstream of the transcription start site. Both elements direct reporter gene expression in Schwann cells and are responsive to the transcription factor SOX10, which is essential for peripheral nervous system myelination. The downstream enhancer harbors a single-nucleotide polymorphism (SNP) that causes an ∼80% reduction in enhancer activity. The SNP resides directly within a predicted binding site for the transcription factor cAMP response element binding protein (CREB), and we demonstrate that this regulatory element binds to CREB and is activated by CREB expression. Finally, forskolin induces Sh3tc2 expression in rat primary Schwann cells, indicating that SH3TC2 is a CREB target gene. These findings prompted us to determine if SNP genotypes at SH3TC2 are associated with differential phenotypes in the most common demyelinating peripheral neuropathy, CMT1A. Interestingly, this revealed several associations between SNP alleles and disease severity. In summary, our data indicate that SH3TC2 is regulated by the transcription factors CREB and SOX10, define a regulatory SNP at this disease-associated locus and reveal SH3TC2 as a candidate modifier locus of CMT disease phenotypes.
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Affiliation(s)
| | - Ki Hwan Ma
- Cellular and Molecular Pathology (CMP) Program
| | - Gary W Beecham
- Dr John T. Macdonald Foundation Department of Human Genetics and John P. Hussman Institute for Human Genomics, University of Miami Miller School of Medicine, Miami, FL, USA
| | - Chetna Gopinath
- Cellular and Molecular Biology Program, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Frank Baas
- Department of Genome Analysis, Academic Medical Centre, Amsterdam, The Netherlands
| | - Byung-Ok Choi
- Department of Neurology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Gangnam-Gu, Seoul, Korea
| | - Mary M Reilly
- MRC Centre for Neuromuscular Diseases, UCL Institute of Neurology, Queen Square, London, UK
| | - Michael E Shy
- Department of Neurology Department of Pediatrics and Department of Physiology, Carver College of Medicine, University of Iowa, Iowa City, IA, USA
| | - Stephan Züchner
- Dr John T. Macdonald Foundation Department of Human Genetics and John P. Hussman Institute for Human Genomics, University of Miami Miller School of Medicine, Miami, FL, USA
| | - John Svaren
- Waisman Center and Department of Comparative Biosciences, University of Wisconsin-Madison, Madison, WI, USA
| | - Anthony Antonellis
- Department of Human Genetics Department of Neurology and Cellular and Molecular Biology Program, University of Michigan Medical School, Ann Arbor, MI, USA
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56
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Abstract
All mammalian uteri contain glands in the endometrium that synthesize or transport and secrete substances essential for survival and development of the conceptus (embryo/fetus and associated extraembryonic membranes). This review summarizes information related to the biological roles of uterine glands and their secretions in blastocyst/conceptus survival and implantation, uterine receptivity, and stromal cell decidualization in humans and animal models. The infertility and recurrent pregnancy loss observed in the ovine uterine gland knockout (UGKO) model unequivocally supports a primary role for uterine glands and, by inference, their secretions present in uterine luminal fluid in survival and development of the conceptus. Further, studies with mutant and progesterone-induced UGKO mice found that uterine glands and their secretions are required for establishment of uterine receptivity and blastocyst implantation as well as stromal cell decidualization. Similarly in humans, uterine glands and their secretory products are likely critical regulators of blastocyst implantation, uterine receptivity, and conceptus growth and development during the first trimester. Circumstantial evidence suggests that deficient glandular activity may be a causative factor in pregnancy failure and complications in humans. Thus, an increased understanding of uterine gland biology is important for diagnosis, prevention, and treatment of fertility and pregnancy problems in mammals.
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Affiliation(s)
- Thomas E Spencer
- Department of Animal Sciences, Center for Reproductive Biology, Washington State University, Pullman, Washington
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57
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Zenker J, Stettner M, Ruskamo S, Domènech-Estévez E, Baloui H, Médard JJ, Verheijen MHG, Brouwers JF, Kursula P, Kieseier BC, Chrast R. A role of peripheral myelin protein 2 in lipid homeostasis of myelinating Schwann cells. Glia 2014; 62:1502-12. [PMID: 24849898 DOI: 10.1002/glia.22696] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2014] [Revised: 05/06/2014] [Accepted: 05/07/2014] [Indexed: 01/28/2023]
Abstract
Peripheral myelin protein 2 (Pmp2, P2 or Fabp8), a member of the fatty acid binding protein family, was originally described together with myelin basic protein (Mbp or P1) and myelin protein zero (Mpz or P0) as one of the most abundant myelin proteins in the peripheral nervous system (PNS). Although Pmp2 is predominantly expressed in myelinated Schwann cells, its role in glia is currently unknown. To study its function in PNS biology, we have generated a complete Pmp2 knockout mouse (Pmp2(-/-) ). Comprehensive characterization of Pmp2(-/-) mice revealed a temporary reduction in their motor nerve conduction velocity (MNCV). While this change was not accompanied by any defects in general myelin structure, we detected transitory alterations in the myelin lipid profile of Pmp2(-/-) mice. It was previously proposed that Pmp2 and Mbp have comparable functions in the PNS suggesting that the presence of Mbp can partially mask the Pmp2(-/-) phenotype. Indeed, we found that Mbp lacking Shi(-/-) mice, similar to Pmp2(-/-) animals, have preserved myelin structure and reduced MNCV, but this phenotype was not aggravated in Pmp2(-/-) /Shi(-/-) mutants indicating that Pmp2 and Mbp do not substitute each other's functions in the PNS. These data, together with our observation that Pmp2 binds and transports fatty acids to membranes, uncover a role for Pmp2 in lipid homeostasis of myelinating Schwann cells.
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Affiliation(s)
- Jennifer Zenker
- Department of Medical Genetics, University of Lausanne, Switzerland; Graduate Program in Neurosciences, University of Lausanne, Switzerland
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58
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Neuropathologic Characterization ofINF2-Related Charcot-Marie-Tooth Disease: Evidence for a Schwann Cell Actinopathy. J Neuropathol Exp Neurol 2014; 73:223-33. [DOI: 10.1097/nen.0000000000000047] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
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59
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Samara C, Poirot O, Domènech-Estévez E, Chrast R. Neuronal activity in the hub of extrasynaptic Schwann cell-axon interactions. Front Cell Neurosci 2013; 7:228. [PMID: 24324401 PMCID: PMC3839048 DOI: 10.3389/fncel.2013.00228] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2013] [Accepted: 11/05/2013] [Indexed: 12/21/2022] Open
Abstract
The integrity and function of neurons depend on their continuous interactions with glial cells. In the peripheral nervous system glial functions are exerted by Schwann cells (SCs). SCs sense synaptic and extrasynaptic manifestations of action potential propagation and adapt their physiology to support neuronal activity. We review here existing literature data on extrasynaptic bidirectional axon-SC communication, focusing particularly on neuronal activity implications. To shed light on underlying mechanisms, we conduct a thorough analysis of microarray data from SC-rich mouse sciatic nerve at different developmental stages and in neuropathic models. We identify molecules that are potentially involved in SC detection of neuronal activity signals inducing subsequent glial responses. We further suggest that alterations in the activity-dependent axon-SC crosstalk impact on peripheral neuropathies. Together with previously reported data, these observations open new perspectives for deciphering glial mechanisms of neuronal function support.
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Affiliation(s)
- Chrysanthi Samara
- Department of Medical Genetics, University of Lausanne Lausanne, Switzerland
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60
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Nicolaou P, Christodoulou K. Advances in the molecular diagnosis of Charcot-Marie-Tooth disease. World J Neurol 2013; 3:42-55. [DOI: 10.5316/wjn.v3.i3.42] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/27/2013] [Revised: 07/23/2013] [Accepted: 08/16/2013] [Indexed: 02/06/2023] Open
Abstract
Charcot-Marie-Tooth (CMT) disease or hereditary motor and sensory neuropathy is the most common inherited neuromuscular disorder affecting at least 1 in 2500. CMT disease is pathologically and genetically heterogeneous and is characterized by a variable age of onset, slowly progressive weakness and muscle atrophy, starting in the lower limbs and subsequently affecting the upper extremities. Symptoms are usually slowly progressive, especially for the classic and late-onset phenotypes, but can be rather severe in early-onset forms. CMT is grouped into demyelinating, axonal and intermediate forms, based on electrophysiological and pathological findings. The demyelinating types are characterized by severely reduced motor nerve conduction velocities (MNCVs) and mainly by myelin abnormalities. The axonal types are characterized by normal or slightly reduced MNCVs and mainly axonal abnormalities. The intermediate types are characterized by MNCVs between 25 m/s and 45 m/s and they have features of both demyelination and axonopathy. Inheritance can be autosomal dominant, X-linked, or autosomal recessive. Mutations in more than 30 genes have been associated with the different forms of CMT, leading to major advancements in molecular diagnostics of the disease, as well as in the understanding of pathogenetic mechanisms. This editorial aims to provide an account that is practicable and efficient on the current molecular diagnostic procedures for CMT, in correlation with the clinical, pathological and electrophysiological findings. The most frequent causative mutations of CMT will also be outlined.
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Tazir M, Bellatache M, Nouioua S, Vallat JM. Autosomal recessive Charcot-Marie-Tooth disease: from genes to phenotypes. J Peripher Nerv Syst 2013; 18:113-29. [DOI: 10.1111/jns5.12026] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2013] [Revised: 03/19/2013] [Accepted: 03/19/2013] [Indexed: 11/27/2022]
Affiliation(s)
- Meriem Tazir
- Service de Neurologie; University Hospital Mustapha Bacha; Alger Algeria
- Laboratoire de NeuroSciences; Université d'Alger 1; Alger Algeria
| | - Mounia Bellatache
- Service de Neurologie; University Hospital Mustapha Bacha; Alger Algeria
- Laboratoire de NeuroSciences; Université d'Alger 1; Alger Algeria
| | - Sonia Nouioua
- Service de Neurologie; University Hospital Mustapha Bacha; Alger Algeria
- Laboratoire de NeuroSciences; Université d'Alger 1; Alger Algeria
| | - Jean-Michel Vallat
- Centre de Référence ⟨Neuropathies Périphériques Rares⟩, Service et Laboratoire de Neurologie; University Hospital; Limoges France
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Gouttenoire EA, Lupo V, Calpena E, Bartesaghi L, Schüpfer F, Médard JJ, Maurer F, Beckmann JS, Senderek J, Palau F, Espinós C, Chrast R. Sh3tc2 deficiency affects neuregulin-1/ErbB signaling. Glia 2013; 61:1041-51. [PMID: 23553667 DOI: 10.1002/glia.22493] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2012] [Accepted: 02/01/2013] [Indexed: 12/19/2022]
Abstract
Mutations in SH3TC2 trigger autosomal recessive demyelinating Charcot-Marie-Tooth type 4C (CMT4C) neuropathy. Sh3tc2 is specifically expressed in Schwann cells and is necessary for proper myelination of peripheral axons. In line with the early onset of neuropathy observed in patients with CMT4C, our analyses of the murine model of CMT4C revealed that the myelinating properties of Sh3tc2-deficient Schwann cells are affected at an early stage. This early phenotype is associated with changes in the canonical Nrg1/ErbB pathway involved in control of myelination. We demonstrated that Sh3tc2 interacts with ErbB2 and plays a role in the regulation of ErbB2 intracellular trafficking from the plasma membrane upon Nrg1 activation. Interestingly, both the loss of Sh3tc2 function in mice and the pathological mutations present in CMT4C patients affect ErbB2 internalization, potentially altering its downstream intracellular signaling pathways. Altogether, our results indicate that the molecular mechanism for the axonal size sensing is disturbed in Sh3tc2-deficient myelinating Schwann cells, thus providing a novel insight into the pathophysiology of CMT4C neuropathy.
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Molecular analysis of the genes causing recessive demyelinating Charcot-Marie-Tooth disease in Japan. J Hum Genet 2013; 58:273-8. [PMID: 23466821 DOI: 10.1038/jhg.2013.15] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Charcot-Marie-Tooth disease (CMT), the most common hereditary neuropathy, has been classified into two types, demyelinating and axonal types. We previously analyzed the genes causing dominant demyelinating CMT in 227 Japanese patients to identify the genetic background, but could not find any mutations in 110 patients. To investigate the frequency of patients with autosomal recessive demyelinating CMT (CMT4) mutations, we analyzed the coding sequence of known causative genes of CMT4 in 103 demyelinating CMT patients, excluding seven patients owing to lack of specimens. We found one patient with a GDAP1 mutation, one patient with an MTMR2 mutation, two patients with SH3TC2/KIAA1985 mutations and three patients with FGD4 mutations. Twelve patients, including five previously detected patients with PRX mutations, were diagnosed as CMT4, accounting for 5.5% of demyelinating CMT. In the patient with GDAP1 mutation, only one mutation inherited from his mother was detected by genomic sequencing. Analysis by reverse transcription polymerase chain reaction using messenger RNA (mRNA) from the patient's leukocytes revealed the absence of transcription from the allele inherited from his father, suggesting the existence of one more mutation leading to a lack or destabilization of mRNA. Most patients carrying CMT4 gene mutations present with early-onset and slowly progressive symptoms, which may be associated with the function of mutants. We could not identify the disease-causing gene in 96 patients (about 45%). Further studies including studies with next-generation sequencers will be required to identify the causative gene in Japanese CMT.
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Lee SM, Sha D, Mohammed AA, Asress S, Glass JD, Chin LS, Li L. Motor and sensory neuropathy due to myelin infolding and paranodal damage in a transgenic mouse model of Charcot-Marie-Tooth disease type 1C. Hum Mol Genet 2013; 22:1755-70. [PMID: 23359569 DOI: 10.1093/hmg/ddt022] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
Charcot-Marie-Tooth disease type 1C (CMT1C) is a dominantly inherited motor and sensory neuropathy. Despite human genetic evidence linking missense mutations in SIMPLE to CMT1C, the in vivo role of CMT1C-linked SIMPLE mutations remains undetermined. To investigate the molecular mechanism underlying CMT1C pathogenesis, we generated transgenic mice expressing either wild-type or CMT1C-linked W116G human SIMPLE. Mice expressing mutant, but not wild type, SIMPLE develop a late-onset motor and sensory neuropathy that recapitulates key clinical features of CMT1C disease. SIMPLE mutant mice exhibit motor and sensory behavioral impairments accompanied by decreased motor and sensory nerve conduction velocity and reduced compound muscle action potential amplitude. This neuropathy phenotype is associated with focally infolded myelin loops that protrude into the axons at paranodal regions and near Schmidt-Lanterman incisures of peripheral nerves. We find that myelin infolding is often linked to constricted axons with signs of impaired axonal transport and to paranodal defects and abnormal organization of the node of Ranvier. Our findings support that SIMPLE mutation disrupts myelin homeostasis and causes peripheral neuropathy via a combination of toxic gain-of-function and dominant-negative mechanisms. The results from this study suggest that myelin infolding and paranodal damage may represent pathogenic precursors preceding demyelination and axonal degeneration in CMT1C patients.
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Affiliation(s)
- Samuel M Lee
- Department of Pharmacology, Emory University School of Medicine, Atlanta, GA 30322, USA
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Parman Y, Battaloğlu E. Recessively transmitted predominantly motor neuropathies. HANDBOOK OF CLINICAL NEUROLOGY 2013; 115:847-861. [PMID: 23931818 DOI: 10.1016/b978-0-444-52902-2.00048-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Recessively transmitted predominantly motor neuropathies are rare and show a severe phenotype. They are frequently observed in populations with a high rate of consanguineous marriages. At least 15 genes and six loci have been found to be associated with autosomal recessive CMT (AR-CMT) and X-linked CMT (AR-CMTX) and also distal hereditary motor neuronopathy (AR-dHMN). These disorders are genetically heterogeneous but the clinical phenotype is relatively homogeneous. Distal muscle weakness and atrophy predominating in the lower extremities, diminished or absent deep tendon reflexes, distal sensory loss, and pes cavus are the main clinical features of this disorder with occasional cranial nerve involvement. Although genetic diagnosis of some of subtypes of AR-CMT are now available, rapid advances in the molecular genetics and cell biology show a great complexity. Animal models for the most common subtypes of human AR-CMT disease provide clues for understanding the pathogenesis of CMT and also help to reveal possible treatment strategies of inherited neuropathies. This chapter highlights the clinical features and the recent genetic and biological findings in these disorders based on the current classification.
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Affiliation(s)
- Yeşim Parman
- Department of Neurology, Istanbul University, Istanbul Medical Faculty, Istanbul, Turkey.
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Iguchi M, Hashiguchi A, Ito E, Toda K, Urano M, Shimizu Y, Takeuchi C, Saito K, Takashima H, Uchiyama S. Charcot-marie-tooth disease type 4C in Japan: Report of a case. Muscle Nerve 2012; 47:283-6. [DOI: 10.1002/mus.23540] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/28/2012] [Indexed: 11/07/2022]
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Azzedine H, Senderek J, Rivolta C, Chrast R. Molecular genetics of charcot-marie-tooth disease: from genes to genomes. Mol Syndromol 2012; 3:204-14. [PMID: 23293578 DOI: 10.1159/000343487] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Charcot-Marie-Tooth disease (CMT) is a heterogeneous group of disorders of the peripheral nervous system, mainly characterized by distal muscle weakness and atrophy leading to motor handicap. With an estimated prevalence of 1 in 2,500, this condition is one of the most commonly inherited neurological disorders. Mutations in more than 30 genes affecting glial and/or neuronal functions have been associated with different forms of CMT leading to a substantial improvement in diagnostics of the disease and in the understanding of implicated pathophysiological mechanisms. However, recent data from systematic genetic screening performed in large cohorts of CMT patients indicated that molecular diagnosis could be established only in ∼50-70% of them, suggesting that additional genes are involved in this disease. In addition to providing an overview of genetic and functional data concerning various CMT forms, this review focuses on recent data generated through the use of highly parallel genetic technologies (SNP chips, sequence capture and next-generation DNA sequencing) in CMT families, and the current and future impact of these technologies on gene discovery and diagnostics of CMTs.
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Affiliation(s)
- H Azzedine
- Department of Medical Genetics, University of Lausanne, Lausanne, Switzerland
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68
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Azzedine H, Senderek J, Rivolta C, Chrast R. Molecular genetics of charcot-marie-tooth disease: from genes to genomes. Mol Syndromol 2012. [PMID: 23293578 DOI: 10.1159/000343487/msy-0003-0204] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Charcot-Marie-Tooth disease (CMT) is a heterogeneous group of disorders of the peripheral nervous system, mainly characterized by distal muscle weakness and atrophy leading to motor handicap. With an estimated prevalence of 1 in 2,500, this condition is one of the most commonly inherited neurological disorders. Mutations in more than 30 genes affecting glial and/or neuronal functions have been associated with different forms of CMT leading to a substantial improvement in diagnostics of the disease and in the understanding of implicated pathophysiological mechanisms. However, recent data from systematic genetic screening performed in large cohorts of CMT patients indicated that molecular diagnosis could be established only in ∼50-70% of them, suggesting that additional genes are involved in this disease. In addition to providing an overview of genetic and functional data concerning various CMT forms, this review focuses on recent data generated through the use of highly parallel genetic technologies (SNP chips, sequence capture and next-generation DNA sequencing) in CMT families, and the current and future impact of these technologies on gene discovery and diagnostics of CMTs.
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Affiliation(s)
- H Azzedine
- Department of Medical Genetics, University of Lausanne, Lausanne, Switzerland
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69
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Lee SM, Chin LS, Li L. Therapeutic implications of protein homeostasis in demyelinating peripheral neuropathies. Expert Rev Neurother 2012; 12:1041-3. [PMID: 23039381 DOI: 10.1586/ern.12.79] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
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Abstract
The prenatal and infantile neuropathies are an uncommon and complex group of conditions, most of which are genetic. Despite advances in diagnostic techniques, approximately half of children presenting in infancy remain without a specific diagnosis. This review focuses on inherited demyelinating neuropathies presenting in the first year of life. We clarify the nomenclature used in these disorders, review the clinical features of demyelinating forms of Charcot-Marie-Tooth disease with early onset, and discuss the demyelinating infantile neuropathies associated with central nervous system involvement. Useful clinical, neurophysiologic, and neuropathologic features in the diagnostic work-up of these conditions are also presented.
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Affiliation(s)
- Eppie M Yiu
- Children's Neuroscience Centre, Royal Children's Hospital, Flemington Road, Parkville, Victoria, Australia
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Altered distribution of juxtaparanodal kv1.2 subunits mediates peripheral nerve hyperexcitability in type 2 diabetes mellitus. J Neurosci 2012; 32:7493-8. [PMID: 22649228 DOI: 10.1523/jneurosci.0719-12.2012] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Peripheral nerve hyperexcitability (PNH) is one of the distal peripheral neuropathy phenotypes often present in patients affected by type 2 diabetes mellitus (T2DM). Through in vivo and ex vivo electrophysiological recordings in db/db mice, a model of T2DM, we observed that, in addition to reduced nerve conduction velocity, db/db mice also develop PNH. By using pharmacological inhibitors, we demonstrated that the PNH is mediated by the decreased activity of K(v)1-channels. In agreement with these data, we observed that the diabetic condition led to a reduced presence of the K(v)1.2-subunits in juxtaparanodal regions of peripheral nerves in db/db mice and in nerve biopsies from T2DM patients. Together, these observations indicate that the T2DM condition leads to potassium channel-mediated PNH, thus identifying them as a potential drug target to treat some of the DPN related symptoms.
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Srinivasan R, Sun G, Keles S, Jones EA, Jang SW, Krueger C, Moran JJ, Svaren J. Genome-wide analysis of EGR2/SOX10 binding in myelinating peripheral nerve. Nucleic Acids Res 2012; 40:6449-60. [PMID: 22492709 PMCID: PMC3413122 DOI: 10.1093/nar/gks313] [Citation(s) in RCA: 72] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2011] [Revised: 03/25/2012] [Accepted: 03/26/2012] [Indexed: 11/17/2022] Open
Abstract
Myelin is essential for the rapidity of saltatory nerve conduction, and also provides trophic support for axons to prevent axonal degeneration. Two critical determinants of myelination are SOX10 and EGR2/KROX20. SOX10 is required for specification of Schwann cells from neural crest, and is required at every stage of Schwann cell development. Egr2/Krox20 expression is activated by axonal signals in myelinating Schwann cells, and is required for cell cycle arrest and myelin formation. To elucidate the integrated function of these two transcription factors during peripheral nerve myelination, we performed in vivo ChIP-Seq analysis of myelinating peripheral nerve. Integration of these binding data with loss-of-function array data identified a range of genes regulated by these factors. In addition, although SOX10 itself regulates Egr2/Krox20 expression, leading to coordinate activation of several major myelin genes by the two factors, there is a large subset of genes that are activated independent of EGR2. Finally, the results identify a set of SOX10-dependent genes that are expressed in early Schwann cell development, but become subsequently repressed by EGR2/KROX20.
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Affiliation(s)
- Rajini Srinivasan
- Waisman Center, Department of Statistics, Department of Biostatistics and Medical Informatics, Program in Cellular and Molecular Biology and, Department of Comparative Biosciences, University of Wisconsin, Madison, WI, USA
| | - Guannan Sun
- Waisman Center, Department of Statistics, Department of Biostatistics and Medical Informatics, Program in Cellular and Molecular Biology and, Department of Comparative Biosciences, University of Wisconsin, Madison, WI, USA
| | - Sunduz Keles
- Waisman Center, Department of Statistics, Department of Biostatistics and Medical Informatics, Program in Cellular and Molecular Biology and, Department of Comparative Biosciences, University of Wisconsin, Madison, WI, USA
| | - Erin A. Jones
- Waisman Center, Department of Statistics, Department of Biostatistics and Medical Informatics, Program in Cellular and Molecular Biology and, Department of Comparative Biosciences, University of Wisconsin, Madison, WI, USA
| | - Sung-Wook Jang
- Waisman Center, Department of Statistics, Department of Biostatistics and Medical Informatics, Program in Cellular and Molecular Biology and, Department of Comparative Biosciences, University of Wisconsin, Madison, WI, USA
| | - Courtney Krueger
- Waisman Center, Department of Statistics, Department of Biostatistics and Medical Informatics, Program in Cellular and Molecular Biology and, Department of Comparative Biosciences, University of Wisconsin, Madison, WI, USA
| | - John J. Moran
- Waisman Center, Department of Statistics, Department of Biostatistics and Medical Informatics, Program in Cellular and Molecular Biology and, Department of Comparative Biosciences, University of Wisconsin, Madison, WI, USA
| | - John Svaren
- Waisman Center, Department of Statistics, Department of Biostatistics and Medical Informatics, Program in Cellular and Molecular Biology and, Department of Comparative Biosciences, University of Wisconsin, Madison, WI, USA
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Neural and molecular features on Charcot-Marie-Tooth disease plasticity and therapy. Neural Plast 2012; 2012:171636. [PMID: 22745917 PMCID: PMC3382403 DOI: 10.1155/2012/171636] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2012] [Accepted: 04/16/2012] [Indexed: 12/21/2022] Open
Abstract
In the peripheral nervous system disorders plasticity is related to changes on the axon and Schwann cell biology, and the synaptic formations and connections, which could be also a focus for therapeutic research. Charcot-Marie-Tooth disease (CMT) represents a large group of inherited peripheral neuropathies that involve mainly both motor and sensory nerves and induce muscular atrophy and weakness. Genetic analysis has identified several pathways and molecular mechanisms involving myelin structure and proper nerve myelination, transcriptional regulation, protein turnover, vesicle trafficking, axonal transport and mitochondrial dynamics. These pathogenic mechanisms affect the continuous signaling and dialogue between the Schwann cell and the axon, having as final result the loss of myelin and nerve maintenance; however, some late onset axonal CMT neuropathies are a consequence of Schwann cell specific changes not affecting myelin. Comprehension of molecular pathways involved in Schwann cell-axonal interactions is likely not only to increase the understanding of nerve biology but also to identify the molecular targets and cell pathways to design novel therapeutic approaches for inherited neuropathies but also for most common peripheral neuropathies. These approaches should improve the plasticity of the synaptic connections at the neuromuscular junction and regenerate cell viability based on improving myelin and axon interaction.
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Yger M, Stojkovic T, Tardieu S, Maisonobe T, Brice A, Echaniz-Laguna A, Alembik Y, Girard S, Cazeneuve C, LeGuern E, Dubourg O. Characteristics of clinical and electrophysiological pattern of Charcot-Marie-Tooth 4C. J Peripher Nerv Syst 2012; 17:112-22. [DOI: 10.1111/j.1529-8027.2012.00382.x] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Bangratz M, Sarrazin N, Devaux J, Zambroni D, Echaniz-Laguna A, René F, Boërio D, Davoine CS, Fontaine B, Feltri ML, Benoit E, Nicole S. A mouse model of Schwartz-Jampel syndrome reveals myelinating Schwann cell dysfunction with persistent axonal depolarization in vitro and distal peripheral nerve hyperexcitability when perlecan is lacking. THE AMERICAN JOURNAL OF PATHOLOGY 2012; 180:2040-55. [PMID: 22449950 DOI: 10.1016/j.ajpath.2012.01.035] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/27/2011] [Revised: 12/22/2011] [Accepted: 01/10/2012] [Indexed: 12/31/2022]
Abstract
Congenital peripheral nerve hyperexcitability (PNH) is usually associated with impaired function of voltage-gated K(+) channels (VGKCs) in neuromyotonia and demyelination in peripheral neuropathies. Schwartz-Jampel syndrome (SJS) is a form of PNH that is due to hypomorphic mutations of perlecan, the major proteoglycan of basement membranes. Schwann cell basement membrane and its cell receptors are critical for the myelination and organization of the nodes of Ranvier. We therefore studied a mouse model of SJS to determine whether a role for perlecan in these functions could account for PNH when perlecan is lacking. We revealed a role for perlecan in the longitudinal elongation and organization of myelinating Schwann cells because perlecan-deficient mice had shorter internodes, more numerous Schmidt-Lanterman incisures, and increased amounts of internodal fast VGKCs. Perlecan-deficient mice did not display demyelination events along the nerve trunk but developed dysmyelination of the preterminal segment associated with denervation processes at the neuromuscular junction. Investigating the excitability properties of the peripheral nerve suggested a persistent axonal depolarization during nerve firing in vitro, most likely due to defective K(+) homeostasis, and excluded the nerve trunk as the original site for PNH. Altogether, our data shed light on perlecan function by revealing critical roles in Schwann cell physiology and suggest that PNH in SJS originates distally from synergistic actions of peripheral nerve and neuromuscular junction changes.
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Affiliation(s)
- Marie Bangratz
- INSERM, U975, Research Center of the Brain and Spinal Cord Institute, U975, Paris, France
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Bucci C, Bakke O, Progida C. Charcot-Marie-Tooth disease and intracellular traffic. Prog Neurobiol 2012; 99:191-225. [PMID: 22465036 PMCID: PMC3514635 DOI: 10.1016/j.pneurobio.2012.03.003] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2011] [Revised: 12/23/2011] [Accepted: 03/13/2012] [Indexed: 12/23/2022]
Abstract
Mutations of genes whose primary function is the regulation of membrane traffic are increasingly being identified as the underlying causes of various important human disorders. Intriguingly, mutations in ubiquitously expressed membrane traffic genes often lead to cell type- or organ-specific disorders. This is particularly true for neuronal diseases, identifying the nervous system as the most sensitive tissue to alterations of membrane traffic. Charcot-Marie-Tooth (CMT) disease is one of the most common inherited peripheral neuropathies. It is also known as hereditary motor and sensory neuropathy (HMSN), which comprises a group of disorders specifically affecting peripheral nerves. This peripheral neuropathy, highly heterogeneous both clinically and genetically, is characterized by a slowly progressive degeneration of the muscle of the foot, lower leg, hand and forearm, accompanied by sensory loss in the toes, fingers and limbs. More than 30 genes have been identified as targets of mutations that cause CMT neuropathy. A number of these genes encode proteins directly or indirectly involved in the regulation of intracellular traffic. Indeed, the list of genes linked to CMT disease includes genes important for vesicle formation, phosphoinositide metabolism, lysosomal degradation, mitochondrial fission and fusion, and also genes encoding endosomal and cytoskeletal proteins. This review focuses on the link between intracellular transport and CMT disease, highlighting the molecular mechanisms that underlie the different forms of this peripheral neuropathy and discussing the pathophysiological impact of membrane transport genetic defects as well as possible future ways to counteract these defects.
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Affiliation(s)
- Cecilia Bucci
- Department of Biological and Environmental Sciences and Technologies (DiSTeBA), University of Salento, Via Provinciale Monteroni, 73100 Lecce, Italy.
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Abstract
Nerve biopsy is a valuable tool in the diagnostic work-up of peripheral neuropathies. Currently, major indications include interstitial pathologies such as suspected vasculitis and amyloidosis, atypical cases of inflammatory neuropathy and the differential diagnosis of hereditary neuropathies that cannot be specified otherwise. However, surgical removal of a piece of nerve causes a sensory deficit and – in some cases – chronic pain. Therefore, a nerve biopsy is usually performed only when other clinical, laboratory and electrophysiological methods have failed to clarify the cause of disease. The neuropathological work-up should include at least paraffin and resin semithin histology using a panel of conventional and immunohistochemical stains. Cryostat section staining, teased fiber preparations, electron microscopy and molecular genetic analyses are potentially useful additional methods in a subset of cases. Being performed, processed and read by experienced physicians and technicians nerve biopsies can provide important information relevant for clinical management.
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Espinós C, Calpena E, Martínez-Rubio D, Lupo V. Autosomal Recessive Charcot-Marie-Tooth Neuropathy. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2012; 724:61-75. [DOI: 10.1007/978-1-4614-0653-2_5] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
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Walsh SK, Kumar R, Grochmal JK, Kemp SWP, Forden J, Midha R. Fate of stem cell transplants in peripheral nerves. Stem Cell Res 2011; 8:226-38. [PMID: 22265742 DOI: 10.1016/j.scr.2011.11.004] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/04/2011] [Revised: 09/27/2011] [Accepted: 11/16/2011] [Indexed: 12/14/2022] Open
Abstract
While damaged peripheral nerves demonstrate some potential to regenerate, complete functional recovery remains infrequent, owing to a functional loss of supportive Schwann cells distal to the injury. An emerging solution to improve upon this intrinsic regenerative capacity is to supplement injured nerves with stem cells derived from various tissues. While many of these strategies have proven successful in animal models, few studies have examined the behavior of transplanted stem cells in vivo, including whether they survive and differentiate. In previous work, we demonstrated that cells derived from neonatal rodent dermis (skin-derived precursor cells, or SKPs) could improve regenerative parameters when transplanted distal to both acute and chronic nerve injuries in Lewis rats. The aim of this work was to track the fate of these cells in various nerve injury paradigms and determine the response of these cells to a known glial growth factor. Here, we report that SKPs survive, respond to local cues, differentiate into myelinating Schwann cells, and avoid complete clearance by the host's immune defenses for a minimum of 10weeks. Moreover, the ultimate fate of SKPs in vivo depends on the nerve environment into which they are injected and can be modified by inclusion of heregulin-1β.
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Affiliation(s)
- Sarah K Walsh
- Hotchkiss Brain Institute and Department of Clinical Neuroscience, Faculty of Medicine, University of Calgary, Canada.
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80
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Li X, DiFiglia M. The recycling endosome and its role in neurological disorders. Prog Neurobiol 2011; 97:127-41. [PMID: 22037413 DOI: 10.1016/j.pneurobio.2011.10.002] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2011] [Revised: 10/14/2011] [Accepted: 10/17/2011] [Indexed: 02/08/2023]
Abstract
The recycling endosome (RE) is an organelle in the endocytic pathway where plasma membranes (proteins and lipids) internalized by endocytosis are processed back to the cell surface for reuse. Endocytic recycling is the primary way for the cell to maintain constituents of the plasma membrane (Griffiths et al., 1989), i.e., to maintain the abundance of receptors and transporters on cell surfaces. Membrane traffic through the RE is crucial for several key cellular processes including cytokinesis and cell migration. In polarized cells, including neurons, the RE is vital for the generation and maintenance of the polarity of the plasma membrane. Many RE dependent cargo molecules are known to be important for neuronal function and there is evidence that improper function of key proteins in RE-associated pathways may contribute to the pathogenesis of neurological disorders, including Huntington's disease. The function of the RE in neurons is poorly understood. Therefore, there is need to understand how membrane dynamics in RE-associated pathways are affected or participate in the development or progression of neurological diseases. This review summarizes advances in understanding endocytic recycling associated with the RE, challenges in elucidating molecular mechanisms underlying RE function, and evidence for RE dysfunction in neurological disorders.
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Affiliation(s)
- Xueyi Li
- Laboratory of Cellular Neurobiology and Department of Neurology, Massachusetts General Hospital, 114 16th Street, Charlestown, MA 02129, USA
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81
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Abstract
Charcot-Marie-Tooth disease (CMT) disease encompasses a genetically heterogeneous group of inherited neuropathies, also known as hereditary motor and sensory neuropathies. CMT results from mutations in more than 40 genes expressed in Schwann cells and neurons causing overlapping phenotypes. The classic CMT phenotype reflects length-dependent axonal degeneration characterized by distal sensory loss and weakness, deep tendon reflex abnormalities, and skeletal deformities. Recent articles have provided insight into the molecular pathogenesis of CMT, which, for the first time, suggest potential therapeutic targets. Although there are currently no effective medications for CMT, multiple clinical trials are ongoing or being planned. This review will focus on the underlying pathomechanisms and diagnostic approaches of CMT and discuss the emerging therapeutic strategies.
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Affiliation(s)
- Agnes Patzkó
- Wayne State University, 421 East Canfield, Elliman Building 3209, Detroit, MI 48201, USA.
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82
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Both Schwann cell and axonal defects cause motor peripheral neuropathy in Ebf2−/− mice. Neurobiol Dis 2011; 42:73-84. [DOI: 10.1016/j.nbd.2011.01.006] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2010] [Revised: 12/23/2010] [Accepted: 01/02/2011] [Indexed: 11/24/2022] Open
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83
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Laššuthová P, Mazanec R, Vondráček P, Sišková D, Haberlová J, Sabová J, Seeman P. High frequency of SH3TC2 mutations in Czech HMSN I patients. Clin Genet 2011; 80:334-45. [PMID: 21291453 DOI: 10.1111/j.1399-0004.2011.01640.x] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Charcot-Marie-Tooth (CMT) neuropathy type 4C (CMT4C) is an autosomal recessive (AR), demyelinating neuropathy with early spine deformities caused by mutations in the SH3TC2 gene. To determine the spectrum of SH3TC2 mutations in the Czech population, the entire coding region of SH3TC2 was sequenced in 60 unrelated Czech patients. The prevalent mutation was shown to be the p.Arg954Stop. Therefore, 412 additional patients referred for CMT testing were tested for the presence of p.Arg954Stop only. Of 60 patients in whom the SH3TC2 gene was sequenced, at least one mutation was detected in 13 (21.7%) patients and biallelic pathogenic mutations were detected in 7 (11.6%) patients. Of the 412 patients tested for p.Arg954Stop, the mutation was found in 8 patients (1.94%), 6 were homozygous and 2 were heterozygous. The second causative mutation was detected by sequencing in one of the patients but not in the other. Nine novel sequence variants were detected. Their pathogenicity was further tested in silico and in control samples. Mutations in the SH3TC2 gene are a frequent cause of demyelinating hereditary neuropathy among Czech patients. In total, at least one mutation was found in 21 unrelated patients. CMT4C seems to be the most frequent type of AR CMT and one of the most frequent of all CMT types. Mutation p.Arg954Stop is highly prevalent in the Czech population. Patients with demyelinating neuropathy along with non-dominant mode of inheritance and negative for CMT1A/hereditary neuropathy with liability to pressure palsy should be tested for the presence of the p.Arg954Stop mutation or other mutations in the SH3TC2 gene.
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Affiliation(s)
- P Laššuthová
- DNA Laboratory, Department of Child Neurology, 2nd Medical School, University Hospital Motol, Prague, Czech Republic.
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84
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Stendel C, Roos A, Kleine H, Arnaud E, Ozçelik M, Sidiropoulos PNM, Zenker J, Schüpfer F, Lehmann U, Sobota RM, Litchfield DW, Lüscher B, Chrast R, Suter U, Senderek J. SH3TC2, a protein mutant in Charcot-Marie-Tooth neuropathy, links peripheral nerve myelination to endosomal recycling. ACTA ACUST UNITED AC 2010; 133:2462-74. [PMID: 20826437 DOI: 10.1093/brain/awq168] [Citation(s) in RCA: 69] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
Patients with Charcot-Marie-Tooth neuropathy and gene targeting in mice revealed an essential role for the SH3TC2 gene in peripheral nerve myelination. SH3TC2 expression is restricted to Schwann cells in the peripheral nervous system, and the gene product, SH3TC2, localizes to the perinuclear recycling compartment. Here, we show that SH3TC2 interacts with the small guanosine triphosphatase Rab11, which is known to regulate the recycling of internalized membranes and receptors back to the cell surface. Results of protein binding studies and transferrin receptor trafficking are in line with a role of SH3TC2 as a Rab11 effector molecule. Consistent with a function of Rab11 in Schwann cell myelination, SH3TC2 mutations that cause neuropathy disrupt the SH3TC2/Rab11 interaction, and forced expression of dominant negative Rab11 strongly impairs myelin formation in vitro. Our data indicate that the SH3TC2/Rab11 interaction is relevant for peripheral nerve pathophysiology and place endosomal recycling on the list of cellular mechanisms involved in Schwann cell myelination.
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Affiliation(s)
- Claudia Stendel
- Institute of Cell Biology, Department of Biology, ETH Zürich, Zürich, Switzerland
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85
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Cartoni R, Arnaud E, Médard JJ, Poirot O, Courvoisier DS, Chrast R, Martinou JC. Expression of mitofusin 2R94Q in a transgenic mouse leads to Charcot–Marie–Tooth neuropathy type 2A. Brain 2010; 133:1460-9. [DOI: 10.1093/brain/awq082] [Citation(s) in RCA: 90] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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86
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Lupski JR, Reid JG, Gonzaga-Jauregui C, Rio Deiros D, Chen DCY, Nazareth L, Bainbridge M, Dinh H, Jing C, Wheeler DA, McGuire AL, Zhang F, Stankiewicz P, Halperin JJ, Yang C, Gehman C, Guo D, Irikat RK, Tom W, Fantin NJ, Muzny DM, Gibbs RA. Whole-genome sequencing in a patient with Charcot-Marie-Tooth neuropathy. N Engl J Med 2010; 362:1181-91. [PMID: 20220177 PMCID: PMC4036802 DOI: 10.1056/nejmoa0908094] [Citation(s) in RCA: 621] [Impact Index Per Article: 44.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
BACKGROUND Whole-genome sequencing may revolutionize medical diagnostics through rapid identification of alleles that cause disease. However, even in cases with simple patterns of inheritance and unambiguous diagnoses, the relationship between disease phenotypes and their corresponding genetic changes can be complicated. Comprehensive diagnostic assays must therefore identify all possible DNA changes in each haplotype and determine which are responsible for the underlying disorder. The high number of rare, heterogeneous mutations present in all humans and the paucity of known functional variants in more than 90% of annotated genes make this challenge particularly difficult. Thus, the identification of the molecular basis of a genetic disease by means of whole-genome sequencing has remained elusive. We therefore aimed to assess the usefulness of human whole-genome sequencing for genetic diagnosis in a patient with Charcot-Marie-Tooth disease. METHODS We identified a family with a recessive form of Charcot-Marie-Tooth disease for which the genetic basis had not been identified. We sequenced the whole genome of the proband, identified all potential functional variants in genes likely to be related to the disease, and genotyped these variants in the affected family members. RESULTS We identified and validated compound, heterozygous, causative alleles in SH3TC2 (the SH3 domain and tetratricopeptide repeats 2 gene), involving two mutations, in the proband and in family members affected by Charcot-Marie-Tooth disease. Separate subclinical phenotypes segregated independently with each of the two mutations; heterozygous mutations confer susceptibility to neuropathy, including the carpal tunnel syndrome. CONCLUSIONS As shown in this study of a family with Charcot-Marie-Tooth disease, whole-genome sequencing can identify clinically relevant variants and provide diagnostic information to inform the care of patients.
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Affiliation(s)
- James R Lupski
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, USA
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87
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Roberts RC, Peden AA, Buss F, Bright NA, Latouche M, Reilly MM, Kendrick-Jones J, Luzio JP. Mistargeting of SH3TC2 away from the recycling endosome causes Charcot-Marie-Tooth disease type 4C. Hum Mol Genet 2010; 19:1009-18. [PMID: 20028792 PMCID: PMC2830826 DOI: 10.1093/hmg/ddp565] [Citation(s) in RCA: 62] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2009] [Accepted: 12/19/2009] [Indexed: 12/26/2022] Open
Abstract
Mutations in the functionally uncharacterized protein SH3TC2 are associated with the severe hereditary peripheral neuropathy, Charcot-Marie-Tooth disease type 4C (CMT4C). Similarly, to other proteins mutated in CMT, a role for SH3TC2 in endocytic membrane traffic has been previously proposed. However, recent descriptions of the intracellular localization of SH3TC2 are conflicting. Furthermore, no clear functional pathogenic mechanisms have so far been proposed to explain why both nonsense and missense mutations in SH3TC2 lead to similar clinical phenotypes. Here, we describe our intracellular localization studies, supported by biochemical and functional data, using wild-type and mutant SH3TC2. We show that wild-type SH3TC2 targets to the intracellular recycling endosome by associating with the small GTPase, Rab11, which is known to regulate the recycling of internalized membrane and receptors back to the plasma membrane. Furthermore, we demonstrate that SH3TC2 interacts preferentially with the GTP-bound form of Rab11, identifying SH3TC2 as a novel Rab11 effector. Of clinical pathological relevance, all SH3TC2 constructs harbouring disease-causing mutations are shown to be unable to associate with Rab11 with consequent loss of recycling endosome localization. Moreover, we show that wild-type SH3TC2, but not mutant SH3TC2, influences transferrin receptor dynamics, consistent with a functional role on the endocytic recycling pathway. Our data therefore implicate mistargeting of SH3TC2 away from the recycling endosome as the fundamental molecular defect that leads to CMT4C.
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Affiliation(s)
- Rhys C Roberts
- Cambridge Institute for Medical Research, University of Cambridge, Cambridge CB2 0XY, UK.
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