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Kraoua I, Bouyacoub Y, Drissi C, Chargui M, Rebai I, Chebil A, Klaa H, Benrhouma H, Hassen A, Gouider-Khouja N, Abdelhak S, Boespflug-Tanguy O, Youssef-Turki IB, Dorboz I. Hypomyelination and Congenital Cataract: Clinical, Imaging, and Genetic Findings in Three Tunisian Families and Literature Review. Neuropediatrics 2021; 52:302-309. [PMID: 34192786 DOI: 10.1055/s-0041-1728654] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
Hypomyelination and congenital cataract (HCC) is characterized by congenital cataract, progressive neurologic impairment, and diffuse myelin deficiency. This autosomal recessive disorder is caused by homozygous variant in the FAM126A gene. Five consanguineous Tunisian patients, belonging to three unrelated families, underwent routine blood tests, electroneuromyography, and magnetic resonance imaging of the brain. The direct sequencing of FAM126A exons was performed for the patients and their relatives. We summarized the 30 previously published HCC cases. All of our patients were carriers of a previously reported c.414 + 1G > T (IVS5 + 1G > T) variant, but the clinical spectrum was variable. Despite the absence of a phenotype-genotype correlation in HCC disease, screening of this splice site variant should be performed in family members at risk.
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Affiliation(s)
- Ichraf Kraoua
- LR18SP04, Department of Child and Adolescent Neurology, National Institute Mongi Ben Hmida of Neurology, University of Tunis El Manar, Tunis, Tunisia
| | - Yosra Bouyacoub
- LR11IPT05, Laboratory of Biomedical Genomics and Oncogenetics, Pasteur Institute of Tunis, University of Tunis El Manar, Tunis, Tunisia
| | - Cyrine Drissi
- Department of Neuroradiology, National Institute Mongi Ben Hmida of Neurology, Tunis, Tunisia
| | - Mariem Chargui
- LR11IPT05, Laboratory of Biomedical Genomics and Oncogenetics, Pasteur Institute of Tunis, University of Tunis El Manar, Tunis, Tunisia
| | - Ibtihel Rebai
- LR18SP04, Department of Child and Adolescent Neurology, National Institute Mongi Ben Hmida of Neurology, University of Tunis El Manar, Tunis, Tunisia
| | - Ahmed Chebil
- Department B of Ophthalmology, Hedi Rais Institute of Ophthalmology, Faculty of Medicine of Tunis, University of Tunis El Manar, Tunis, Tunisia
| | - Hédia Klaa
- LR18SP04, Department of Child and Adolescent Neurology, National Institute Mongi Ben Hmida of Neurology, University of Tunis El Manar, Tunis, Tunisia
| | - Hanene Benrhouma
- LR18SP04, Department of Child and Adolescent Neurology, National Institute Mongi Ben Hmida of Neurology, University of Tunis El Manar, Tunis, Tunisia
| | - Aida Hassen
- LR18SP04, Department of Child and Adolescent Neurology, National Institute Mongi Ben Hmida of Neurology, University of Tunis El Manar, Tunis, Tunisia
| | - Neziha Gouider-Khouja
- LR18SP04, Department of Child and Adolescent Neurology, National Institute Mongi Ben Hmida of Neurology, University of Tunis El Manar, Tunis, Tunisia
| | - Sonia Abdelhak
- LR11IPT05, Laboratory of Biomedical Genomics and Oncogenetics, Pasteur Institute of Tunis, University of Tunis El Manar, Tunis, Tunisia
| | - Odile Boespflug-Tanguy
- Université de Paris, NeuroDiderot, UMR 1141, INSERM, Neuropédiatrie, LEUKOFRANCE, APHP, Hôpital Robert Debré, France
| | - Ilhem Ben Youssef-Turki
- LR18SP04, Department of Child and Adolescent Neurology, National Institute Mongi Ben Hmida of Neurology, University of Tunis El Manar, Tunis, Tunisia
| | - Imen Dorboz
- Université de Paris, NeuroDiderot, UMR 1141, INSERM, Neuropédiatrie, LEUKOFRANCE, APHP, Hôpital Robert Debré, France
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Karalok ZS, Gurkasb E, Aydinc K, Ceylaner S. Hypomyelination and Congenital Cataract: Three Siblings Presentation. J Pediatr Neurosci 2021; 15:270-273. [PMID: 33531944 PMCID: PMC7847105 DOI: 10.4103/jpn.jpn_161_18] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2018] [Revised: 11/18/2019] [Accepted: 05/24/2020] [Indexed: 11/25/2022] Open
Abstract
Hypomyelination and congenital cataract (HCC) is a condition, which is caused by mutations in the FAM126A gene and is characterized by congenital cataract, progressive neurologic impairment, and myelin deficiency in both the central and peripheral nervous system. We present the findings of three siblings who applied to us with the same clinical features. These patients were referred to our clinic due to the presence of bilateral congenital cataract and progressive neurological impairment with peripheral neuropathy. Brain magnetic resonance imaging (MRI) showed diffuse hypomyelination, whereas neurophysiological studies showed sensorimotor peripheral polyneuropathy. Cases with hypomyelination in MRI represent the largest group of undiagnosed diseases among patients with leukoencephalopathies. To diagnose cases with peripheral neuropathy, their clinical and neuroradiological findings must be identified. These findings can guide clinicians to appropriate molecular investigations.
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Affiliation(s)
- Zeynep Selen Karalok
- Department of Pediatric Neurology, Akdeniz University School of Medicine, Antalya, Turkey
| | - Esra Gurkasb
- Department of Pediatric Neurology, Ankara Children's Hospital Hematology-Oncology Research and Training Hospital, Ankara, Turkey
| | - Kursad Aydinc
- Department of Pediatric Neurology, Medipol University, İstanbul, Turkey
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Matsumoto N, Watanabe N, Iibe N, Tatsumi Y, Hattori K, Takeuchi Y, Oizumi H, Ohbuchi K, Torii T, Miyamoto Y, Yamauchi J. Hypomyelinating leukodystrophy-associated mutation of RARS leads it to the lysosome, inhibiting oligodendroglial morphological differentiation. Biochem Biophys Rep 2019; 20:100705. [PMID: 31737794 PMCID: PMC6849085 DOI: 10.1016/j.bbrep.2019.100705] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2019] [Revised: 06/16/2019] [Accepted: 10/30/2019] [Indexed: 01/25/2023] Open
Abstract
Pelizaeus-Merzbacher disease (PMD) is a central nervous system (CNS) demyelinating disease in human, currently known as prototypic hypomyelinating leukodystrophy 1 (HLD1). The gene responsible for HLD1 encodes proteolipid protein 1 (PLP1), which is the major myelin protein produced by oligodendrocytes. HLD9 is an autosomal recessive disorder responsible for the gene differing from the plp1 gene. The hld9 gene encodes arginyl-tRNA synthetase (RARS), which belongs to a family of cytoplasmic aminoacyl-tRNA synthetases. Herein we show that HLD9-associated missense mutation of Ser456-to-Leu (S456L) localizes RARS proteins as aggregates into the lysosome but not into the endoplasmic reticulum (ER) and the Golgi body. In contrast, wild-type proteins indeed distribute throughout the cytoplasm. Expression of S456L mutant constructs in cells decreases lysosome-related signaling through ribosomal S6 protein phosphorylation, which is known to be required for myelin formation. Cells harboring the S456L mutant constructs fail to exhibit phenotypes with myelin web-like structures following differentiation in FBD-102b cells, as part of the mammalian oligodendroglial cell model, whereas parental cells exhibit them. Collectively, HLD9-associated RARS mutant proteins are specifically localized in the lysosome with downregulation of S6 phosphorylation involved in myelin formation, inhibiting differentiation in FBD-102b cells. These results present some of the molecular and cellular pathological mechanisms for defect in myelin formation underlying HLD9.
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Affiliation(s)
- Naoto Matsumoto
- Laboratory of Molecular Neuroscience and Neurology, Tokyo University of Pharmacy and Life Sciences, Hachioji, Tokyo, 192-0392, Japan
| | - Natsumi Watanabe
- Laboratory of Molecular Neuroscience and Neurology, Tokyo University of Pharmacy and Life Sciences, Hachioji, Tokyo, 192-0392, Japan
| | - Noriko Iibe
- Laboratory of Molecular Neuroscience and Neurology, Tokyo University of Pharmacy and Life Sciences, Hachioji, Tokyo, 192-0392, Japan
| | - Yuriko Tatsumi
- Laboratory of Molecular Neuroscience and Neurology, Tokyo University of Pharmacy and Life Sciences, Hachioji, Tokyo, 192-0392, Japan
| | - Kohei Hattori
- Laboratory of Molecular Neuroscience and Neurology, Tokyo University of Pharmacy and Life Sciences, Hachioji, Tokyo, 192-0392, Japan
| | - Yu Takeuchi
- Laboratory of Molecular Neuroscience and Neurology, Tokyo University of Pharmacy and Life Sciences, Hachioji, Tokyo, 192-0392, Japan
| | - Hiroaki Oizumi
- Tsumura Research Laboratories, Tsumura & Co., Inashiki, Ibaraki, 200-1192, Japan
| | - Katsuya Ohbuchi
- Tsumura Research Laboratories, Tsumura & Co., Inashiki, Ibaraki, 200-1192, Japan
| | - Tomohiro Torii
- Department of Neuroscience, Baylor College of Medicine, Houston, TX, 77030, USA
| | - Yuki Miyamoto
- Laboratory of Molecular Neuroscience and Neurology, Tokyo University of Pharmacy and Life Sciences, Hachioji, Tokyo, 192-0392, Japan.,Department of Pharmacology, National Research Institute for Child Health and Development, Setagaya, Tokyo, 157-8535, Japan
| | - Junji Yamauchi
- Laboratory of Molecular Neuroscience and Neurology, Tokyo University of Pharmacy and Life Sciences, Hachioji, Tokyo, 192-0392, Japan.,Department of Pharmacology, National Research Institute for Child Health and Development, Setagaya, Tokyo, 157-8535, Japan
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Charzewska A, Wierzba J, Iżycka-Świeszewska E, Bekiesińska-Figatowska M, Jurek M, Gintowt A, Kłosowska A, Bal J, Hoffman-Zacharska D. Hypomyelinating leukodystrophies - a molecular insight into the white matter pathology. Clin Genet 2016; 90:293-304. [DOI: 10.1111/cge.12811] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2016] [Revised: 05/24/2016] [Accepted: 05/25/2016] [Indexed: 12/23/2022]
Affiliation(s)
- A. Charzewska
- Institute of Mother and Child, Department of Medical Genetics; Warsaw Poland
| | - J. Wierzba
- Medical University of Gdańsk; Department of Paediatrics, Haemathology & Oncology, Department of General Nursery; Gdańsk Poland
| | - E. Iżycka-Świeszewska
- Medical University of Gdańsk; Department of Pathology & Neuropathology; Copernicus Hospital, Department of Patomorphology; Gdańsk Poland
| | | | - M. Jurek
- Institute of Mother and Child, Department of Medical Genetics; Warsaw Poland
| | - A. Gintowt
- Medical University of Gdańsk; Department of Biology and Genetics; Gdańsk Poland
| | - A. Kłosowska
- Medical University of Gdańsk; Department of Paediatrics, Haemathology & Oncology, Department of General Nursery; Gdańsk Poland
| | - J. Bal
- Institute of Mother and Child, Department of Medical Genetics; Warsaw Poland
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Barkovich AJ, Deon S. Reprint of "Hypomyelinating disorders: An MRI approach. Neurobiol Dis 2016; 92:46-54. [PMID: 27235001 DOI: 10.1016/j.nbd.2015.10.022] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2015] [Revised: 10/10/2015] [Accepted: 10/14/2015] [Indexed: 12/19/2022] Open
Abstract
In recent years, the concept of hypomyelinating disorders has been proposed as a group of disorders with varying systemic manifestations that are identified by MR findings of absence or near absence of the T2 hypointensity that develops in white matter as a result of myelination. Initially proposed as a separate group because they were the largest single category of undiagnosed leukodystrophies, their separation as a distinct group that can be recognized by looking for a specific MRI feature has resulted in a marked increase in their diagnosis and a better understanding of the different causes of hypomyelination. This review will discuss the clinical presentations, imaging findings on standard MRI, and new MRI-related techniques that allow a better understanding of these disorders and proposed methods for quantifying the myelination as a potential means of assessing disease course and the effects of proposed treatments. Disorders with hypomyelination of white matter, or hypomyelinating disorders (HMDs), represent the single largest category among undiagnosed genetic leukoencephalopathies (Schiffmann and van der Knaap, 2009; Steenweg et al., 2010). This group of inborn errors of metabolism is characterized by a magnetic resonance imaging (MRI) appearance of reduced or absent myelin development: delay in the development of T2 hypointensity and, often, T1 hyperintensity in the white matter of the brain. The concept of hypomyelination was first conceptualized by (Schiffmann and van der Knaap, 2009; Steenweg et al., 2010; Schiffmann et al., 1994) in a series of papers that showed that these MRI characteristics were easily recognized, were different from the MRI characteristics of dysmyelinating and demyelinating disorders, and that the combination of these imaging findings with specific other clinical and imaging features could be used to make diagnoses with some confidence. In this manuscript, we will discuss the physiologic and genetic bases of hypomyelinating disorders, as well as their classification, clinical manifestations and imaging characteristics.
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Affiliation(s)
- A James Barkovich
- Neuroradiology Section, Department of Radiology and Biomedical Imaging, UCSF-Benioff Children's Hospital, San Francisco, Q6 CA, United States.
| | - Sean Deon
- University of Colorado Medical Center and Prof. Petra Pouwels, University of Amsterdam
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Barkovich AJ, Deon S. Hypomyelinating disorders: An MRI approach. Neurobiol Dis 2015; 87:50-8. [PMID: 26477299 DOI: 10.1016/j.nbd.2015.10.015] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2015] [Revised: 10/10/2015] [Accepted: 10/14/2015] [Indexed: 12/31/2022] Open
Abstract
In recent years, the concept of hypomyelinating disorders has been proposed as a group of disorders with varying systemic manifestations that are identified by MR findings of absence or near absence of the T2 hypointensity that develops in white matter as a result of myelination. Initially proposed as a separate group because they were the largest single category of undiagnosed leukodystrophies, their separation as a distinct group that can be recognized by looking for a specific MRI feature has resulted in a marked increase in their diagnosis and a better understanding of the different causes of hypomyelination. This review will discuss the clinical presentations, imaging findings on standard MRI, and new MRI-related techniques that allow a better understanding of these disorders and proposed methods for quantifying the myelination as a potential means of assessing disease course and the effects of proposed treatments. Disorders with hypomyelination of white matter, or hypomyelinating disorders (HMDs), represent the single largest category among undiagnosed genetic leukoencephalopathies (Schiffmann and van der Knaap, 2009; Steenweg et al., 2010). This group of inborn errors of metabolism is characterized by a magnetic resonance imaging (MRI) appearance of reduced or absent myelin development: delay in the development of T2 hypointensity and, often, T1 hyperintensity in the white matter of the brain. The concept of hypomyelination was first conceptualized by (Schiffmann and van der Knaap, 2009; Steenweg et al., 2010; Schiffmann et al., 1994) in a series of papers that showed that these MRI characteristics were easily recognized, were different from the MRI characteristics of dysmyelinating and demyelinating disorders, and that the combination of these imaging findings with specific other clinical and imaging features could be used to make diagnoses with some confidence. In this manuscript, we will discuss the physiologic and genetic bases of hypomyelinating disorders, as well as their classification, clinical manifestations and imaging characteristics.
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Affiliation(s)
- A James Barkovich
- Neuroradiology Section, Department of Radiology and Biomedical Imaging, UCSF-Benioff Children's Hospital, San Francisco, Q6 CA, United States.
| | - Sean Deon
- University of Colorado Medical Center and Prof. Petra Pouwels, University of Amsterdam
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Miyamoto Y, Torii T, Eguchi T, Nakamura K, Tanoue A, Yamauchi J. Hypomyelinating leukodystrophy-associated missense mutant of FAM126A/hyccin/DRCTNNB1A aggregates in the endoplasmic reticulum. J Clin Neurosci 2013; 21:1033-9. [PMID: 24417797 DOI: 10.1016/j.jocn.2013.09.014] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2013] [Revised: 08/07/2013] [Accepted: 09/22/2013] [Indexed: 11/25/2022]
Abstract
Hypomyelinating leukodystrophies (HLD) are hereditary central nervous system diseases in which the myelin sheath does not form properly. The disease prototype is the X-linked recessive Pelizaeus-Merzbacher disease (also now known as HLD1), which is caused by the mutation, multiplication, or deletion of the plp1 gene. PLP1 missense mutations lead to protein aggregation and accumulation in subcellular compartments such as the endoplasmic reticulum (ER). The gene responsible for an autosomal recessive Pelizaeus-Merzbacher-like disease called HLD5 is named fam126a (also known as hyccin or drctnnb1a). While the gene mutations often cause FAM126A protein deficiency, one known missense mutation, Leu-53-to-Pro (L53P), allows some protein to be produced. Here, we show that the L53P mutant aggregates in cells, accumulating primarily in the ER. This is in contrast to the wild type FAM126A, which distributes throughout the cytoplasm. In addition, the L53P mutant expression promotes the activities of kinases involved in unfolded protein response. These results suggest that a disease-associated FAM126A missense mutation causes protein accumulation in subcellular compartments, possibly to mediate a disease-associated phenotype, which is similar to what is seen with PLP1.
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Affiliation(s)
- Yuki Miyamoto
- Department of Pharmacology, National Research Institute for Child Health and Development, 2-10-1 Okura, Setagaya, Tokyo 157-8535, Japan
| | - Tomohiro Torii
- Department of Pharmacology, National Research Institute for Child Health and Development, 2-10-1 Okura, Setagaya, Tokyo 157-8535, Japan
| | - Takahiro Eguchi
- The Institute of Medical Science, The University of Tokyo, Minato, Tokyo, Japan
| | - Kazuaki Nakamura
- Department of Pharmacology, National Research Institute for Child Health and Development, 2-10-1 Okura, Setagaya, Tokyo 157-8535, Japan
| | - Akito Tanoue
- Department of Pharmacology, National Research Institute for Child Health and Development, 2-10-1 Okura, Setagaya, Tokyo 157-8535, Japan
| | - Junji Yamauchi
- Department of Pharmacology, National Research Institute for Child Health and Development, 2-10-1 Okura, Setagaya, Tokyo 157-8535, Japan; Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Bunkyo, Tokyo, Japan; Japan Health Sciences Foundation, Chuo, Tokyo, Japan.
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Boespflug-Tanguy O. Inborn errors of brain myelin formation. HANDBOOK OF CLINICAL NEUROLOGY 2013; 113:1581-92. [PMID: 23622380 DOI: 10.1016/b978-0-444-59565-2.00027-7] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Inborn errors of brain myelin formation or hypomyelinating leukodystrophies (HLD) represent a heterogeneous group of white matter diseases related to a primitive impairment of oligodendrocytes to produce myelin in the central nervous system (CNS). Cerebral magnetic resonance imaging (MRI) allows an assessment of the myelination pattern. The clinical presentation is related to the degree of hypomyelination and its consequences on axonal functions. When the gene defect interferes with the active infantile phase of myelination, the consequences might be severe, with delayed and loss of psychomotor development, absence of myelin signal on cerebral MRI and of identifiable waves on cerebral evoked potentials, as described by Pelizaeus and Merzbacher (PMD). When the pathophysiological mechanism is less severe, myelin production is maintained, although signs of progressive axonopathy are observed, related to progressive spastic paraplegia (SPG) associated with cognitive or behavioral disturbances. HLDs have been classified according to gene defects or associated signs. The X-linked HDL1 (PMD and SPG2) is related to the gene that controls the production of the major CNS myelin proteins, the proteolipid proteins (PLP). The gap junction protein, gamma 2 gene (GJC2) encoding oligodendrocyte-specific connexin, has been shown to be involved in the autosomal recessive HLD2 (PMLD1 and SPG44).
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Affiliation(s)
- Odile Boespflug-Tanguy
- National Reference Center for Rare Diseases "leukodystrophies", INSERM U676, Université Paris Diderot, Sorbonne Paris Cité Université and Pediatric Neurology and Metabolic Disease Service, Hôpital Robert Debré, Paris, France.
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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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Gazzerro E, Baldassari S, Giacomini C, Musante V, Fruscione F, La Padula V, Biancheri R, Scarfì S, Prada V, Sotgia F, Duncan ID, Zara F, Werner HB, Lisanti MP, Nobbio L, Corradi A, Minetti C. Hyccin, the molecule mutated in the leukodystrophy hypomyelination and congenital cataract (HCC), is a neuronal protein. PLoS One 2012; 7:e32180. [PMID: 22461884 PMCID: PMC3312879 DOI: 10.1371/journal.pone.0032180] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2011] [Accepted: 01/23/2012] [Indexed: 12/24/2022] Open
Abstract
“Hypomyelination and Congenital Cataract”, HCC (MIM #610532), is an autosomal recessive disorder characterized by congenital cataract and diffuse cerebral and peripheral hypomyelination. HCC is caused by deficiency of Hyccin, a protein whose biological role has not been clarified yet. Since the identification of the cell types expressing a protein of unknown function can contribute to define the physiological context in which the molecule is explicating its function, we analyzed the pattern of Hyccin expression in the central and peripheral nervous system (CNS and PNS). Using heterozygous mice expressing the b-galactosidase (LacZ) gene under control of the Hyccin gene regulatory elements, we show that the gene is primarily expressed in neuronal cells. Indeed, Hyccin-LacZ signal was identified in CA1 hippocampal pyramidal neurons, olfactory bulb, and cortical pyramidal neurons, while it did not colocalize with oligodendroglial or astrocytic markers. In the PNS, Hyccin was detectable only in axons isolated from newborn mice. In the brain, Hyccin transcript levels were higher in early postnatal development (postnatal days 2 and 10) and then declined in adult mice. In a model of active myelinogenesis, organotypic cultures of rat Schwann cells (SC)/Dorsal Root Ganglion (DRG) sensory neurons, Hyccin was detected along the neurites, while it was absent from SC. Intriguingly, the abundance of the molecule was upregulated at postnatal days 10 and 15, in the initial steps of myelinogenesis and then declined at 30 days when the process is complete. As Hyccin is primarily expressed in neurons and its mutation leads to hypomyelination in human patients, we suggest that the protein is involved in neuron-to-glia signalling to initiate or maintain myelination.
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Affiliation(s)
- Elisabetta Gazzerro
- Muscular and Neurodegenerative Disease Unit, G. Gaslini Institute, University of Genoa, Genoa, Italy.
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Blugeon C, Le Crom S, Richard L, Vallat JM, Charnay P, Decker L. Dok4 is involved in Schwann cell myelination and axonal interaction in vitro. Glia 2010; 59:351-62. [DOI: 10.1002/glia.21106] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2010] [Revised: 09/20/2010] [Accepted: 10/12/2010] [Indexed: 12/22/2022]
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