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Muñoz de la Torre LP, Trujillo Hernández A, Eguibar JR, Cortés C, Morales-Ledesma L. Characterization of sperm motility and testosterone secretion in the taiep myelin mutant, a model of demyelination. Anim Reprod 2023; 20:e20220102. [PMID: 38026000 PMCID: PMC10681128 DOI: 10.1590/1984-3143-ar2022-0102] [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: 10/24/2022] [Accepted: 09/17/2023] [Indexed: 12/01/2023] Open
Abstract
Presently, demyelinating diseases have been reported to affect the reproductive life of patients who suffer from them, but the progression of the alterations is unknown, especially in men. To better understand these effects, it is necessary to perform studies in animal models, such as the male taiep rat, which exhibits progressive demyelination of the central nervous system, altered kisspeptin expression at the hypothalamic level, and decreased luteinizing hormone, which could alter sperm quality and testicular diameter. Thus, the objective of the present study was to analyze the diameter of the seminiferous tubules, the sperm motility, and the testosterone levels of 90-day-old male taiep rats. The obtained results indicate that male taiep rats show an increase in testicular size accompanied by an increase in the diameter of the seminiferous tubules of the left testicle. There was also a decrease in progressive motility in sperm samples from the left epididymis of male taiep rats compared to the control group, with no changes in serum testosterone concentration. Therefore, we conclude that male taiep rats with central demyelination show altered testicular diameter and decreased motility in sperm from the left side. This type of studies serves as a basis for proposing possible reproductive strategies to improve the fertility and testicular function of men with demyelinating diseases of the central nervous system.
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Affiliation(s)
- Luz Patricia Muñoz de la Torre
- Posgrado en Ciencias Biológicas, Universidad Nacional Autónoma de México, Ciudad de México, México
- Laboratorio de Fisiología Reproductiva, Unidad de Investigación en Biología de la Reproducción, Facultad de Estudios Superiores Zaragoza, Universidad Nacional Autónoma de México, Ciudad de México, México
| | | | - José Ramón Eguibar
- Vicerrectoría de Investigación y Estudios de Posgrado, Benemérita Universidad Autónoma de Puebla, Puebla, México
| | - Carmen Cortés
- Instituto de Fisiología, Benemérita Universidad Autónoma de Puebla, Puebla, México
| | - Leticia Morales-Ledesma
- Laboratorio de Fisiología Reproductiva, Unidad de Investigación en Biología de la Reproducción, Facultad de Estudios Superiores Zaragoza, Universidad Nacional Autónoma de México, Ciudad de México, México
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2
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Sex-specific hypothalamic expression of kisspeptin, gonadotropin releasing hormone, and kisspeptin receptor in progressive demyelination model. J Chem Neuroanat 2022; 123:102120. [PMID: 35718292 DOI: 10.1016/j.jchemneu.2022.102120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2022] [Revised: 05/24/2022] [Accepted: 06/13/2022] [Indexed: 11/21/2022]
Abstract
Demyelinating diseases, such as multiple sclerosis, decrease the quality of life of patients and can affect reproduction. Assisted reproductive therapies are available, which although effective, aggravate motor symptoms. For this reason, it is important to determine how the control of the hypothalamus-pituitary-gonadal axis is affected in order to develop better strategies for these patients. One way to determine this is using animal models such as the taiep rat, which shows progressive demyelination of the central nervous system, and was used in the present study to characterize the expression of gonadotrophin-releasing hormone (GnRH), Kisspeptin, and kisspeptin receptor (Kiss1R) and luteinizing hormone (LH) secretion. The expression of kisspeptin, GnRH, and Kiss1R was determined at the hypothalamic level by immunofluorescence and serum LH levels were determined by ELISA. The expression of kisspeptin at the hypothalamic level showed sexual dimorphism, where there was an increase in males and a decrease in females during oestrus. There was no change in the expression of GnRH or kisspeptin receptor, regardless of sex. However, a decrease in serum LH concentration was observed in both sexes. The taiep rat showed changes in the expression of kisspeptin at the hypothalamic level. These changes are different from those reported in the literature with the use of animals with experimental allergic encephalomyelitis, this is because both animal models represent different degrees of progression of multiple sclerosis. Our results suggest that the effects on the hypothalamus-pituitary-gonadal axis depend on the differences between the demyelinating processes, their progression, and even individual factors, and it is thus important that fertility treatments are individualized to maximize therapeutic effects.
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3
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Vargas-Castro V, Gomez-Diaz R, Blanco-Alvarez VM, Tomas-Sanchez C, Gonzalez-Vazquez A, Aguilar-Peralta AK, Gonzalez-Barrios JA, Martinez-Fong D, Eguibar JR, Vivar C, Ugarte A, Soto-Rodriguez G, Brambila E, Millán-Perez-Peña L, Leon-Chavez BA. Long-term taurine administration improves motor skills in a tubulinopathy rat model by decreasing oxidative stress and promoting myelination. Mol Cell Neurosci 2021; 115:103643. [PMID: 34186187 DOI: 10.1016/j.mcn.2021.103643] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2021] [Revised: 06/16/2021] [Accepted: 06/19/2021] [Indexed: 11/18/2022] Open
Abstract
The taiep rat undergoes hypomyelination and progressive demyelination caused by an abnormal microtubule accumulation in oligodendrocytes, which elicits neuroinflammation and motor behavior dysfunction. Based on taurine antioxidant and proliferative actions, this work explored whether its sustained administration from the embryonic age to adulthood could prevent neuroinflammation, stimulate cell proliferation, promote myelination, and relieve motor impairment. Taurine (50 mg/L of drinking water = 50 ppm) was given to taiep pregnant rats on gestational day 15 and afterward to the male offspring until eight months of age. We measured the levels of nitric oxide (NO), malondialdehyde + 4-hydroxyalkenals (MDA + 4-HDA), CXCL1, CXCR2 receptor, growth factors (BNDF and FGF2), cell proliferation, and myelin content over time. Integral motor behavior was also evaluated. Our results showed that taurine administration significantly decreased NO and MDA + 4-HDA levels, increased cell proliferation, and promoted myelination in an age- and brain region-dependent fashion compared with untreated taiep rats. Taurine effect on chemokines and growth factors was also variable. Taurine improved vestibular reflexes and limb muscular strength in perinatal rats and fine movements and immobility episodes in adult rats. These results show that chronic taurine administration partially alleviates the taiep neuropathology.
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Affiliation(s)
- Viridiana Vargas-Castro
- Facultad de Ciencias Químicas, Benemérita Universidad Autónoma de Puebla, Puebla, Pue. C. P. 72570, Mexico
| | - Ricardo Gomez-Diaz
- Facultad de Ciencias Químicas, Benemérita Universidad Autónoma de Puebla, Puebla, Pue. C. P. 72570, Mexico
| | - Victor M Blanco-Alvarez
- Facultad de Enfermería, Benemérita Universidad Autónoma de Puebla, Puebla, Pue. C. P. 72304, Mexico
| | - Constantino Tomas-Sanchez
- Facultad de Ciencias Químicas, Benemérita Universidad Autónoma de Puebla, Puebla, Pue. C. P. 72570, Mexico
| | - Alejandro Gonzalez-Vazquez
- Facultad de Ciencias Químicas, Benemérita Universidad Autónoma de Puebla, Puebla, Pue. C. P. 72570, Mexico
| | - Ana Karina Aguilar-Peralta
- Facultad de Ciencias Químicas, Benemérita Universidad Autónoma de Puebla, Puebla, Pue. C. P. 72570, Mexico
| | - Juan A Gonzalez-Barrios
- Laboratorio de Medicina Genómica, Hospital Regional 1° de Octubre, ISSSTE, Mexico City C. P. 07760, Mexico
| | - Daniel Martinez-Fong
- Departamento de Fisiología, Biofísica y Neurociencias, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, Apartado Postal 14-740, C. P. 07000 Mexico City, Mexico
| | - Jose R Eguibar
- Instituto de Fisiología, Benemérita Universidad Autónoma de Puebla, Puebla, Pue. C. P. 72590, Mexico
| | - Carmen Vivar
- Departamento de Fisiología, Biofísica y Neurociencias, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, Apartado Postal 14-740, C. P. 07000 Mexico City, Mexico
| | - Araceli Ugarte
- Instituto de Fisiología, Benemérita Universidad Autónoma de Puebla, Puebla, Pue. C. P. 72590, Mexico
| | - Guadalupe Soto-Rodriguez
- Facultad de Medicina, Benemérita Universidad Autónoma de Puebla, Puebla, Pue. C. P. 72304, Mexico
| | - Eduardo Brambila
- Facultad de Ciencias Químicas, Benemérita Universidad Autónoma de Puebla, Puebla, Pue. C. P. 72570, Mexico
| | - Lourdes Millán-Perez-Peña
- Facultad de Ciencias Químicas, Benemérita Universidad Autónoma de Puebla, Puebla, Pue. C. P. 72570, Mexico
| | - Bertha Alicia Leon-Chavez
- Facultad de Ciencias Químicas, Benemérita Universidad Autónoma de Puebla, Puebla, Pue. C. P. 72570, Mexico.
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4
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Gruenenfelder FI, McLaughlin M, Griffiths IR, Garbern J, Thomson G, Kuzman P, Barrie JA, McCulloch ML, Penderis J, Stassart R, Nave KA, Edgar JM. Neural stem cells restore myelin in a demyelinating model of Pelizaeus-Merzbacher disease. Brain 2020; 143:1383-1399. [PMID: 32419025 PMCID: PMC7462093 DOI: 10.1093/brain/awaa080] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2019] [Revised: 01/20/2020] [Accepted: 02/05/2020] [Indexed: 12/13/2022] Open
Abstract
Pelizaeus-Merzbacher disease is a fatal X-linked leukodystrophy caused by mutations in the PLP1 gene, which is expressed in the CNS by oligodendrocytes. Disease onset, symptoms and mortality span a broad spectrum depending on the nature of the mutation and thus the degree of CNS hypomyelination. In the absence of an effective treatment, direct cell transplantation into the CNS to restore myelin has been tested in animal models of severe forms of the disease with failure of developmental myelination, and more recently, in severely affected patients with early disease onset due to point mutations in the PLP1 gene, and absence of myelin by MRI. In patients with a PLP1 duplication mutation, the most common cause of Pelizaeus-Merzbacher disease, the pathology is poorly defined because of a paucity of autopsy material. To address this, we examined two elderly patients with duplication of PLP1 in whom the overall syndrome, including end-stage pathology, indicated a complex disease involving dysmyelination, demyelination and axonal degeneration. Using the corresponding Plp1 transgenic mouse model, we then tested the capacity of transplanted neural stem cells to restore myelin in the context of PLP overexpression. Although developmental myelination and axonal coverage by endogenous oligodendrocytes was extensive, as assessed using electron microscopy (n = 3 at each of four end points) and immunostaining (n = 3 at each of four end points), wild-type neural precursors, transplanted into the brains of the newborn mutants, were able to effectively compete and replace the defective myelin (n = 2 at each of four end points). These data demonstrate the potential of neural stem cell therapies to restore normal myelination and protect axons in patients with PLP1 gene duplication mutation and further, provide proof of principle for the benefits of stem cell transplantation for other fatal leukodystrophies with 'normal' developmental myelination.
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Affiliation(s)
- Fredrik I Gruenenfelder
- School of Veterinary Medicine, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, G12 8TA, UK
| | - Mark McLaughlin
- School of Veterinary Medicine, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, G12 8TA, UK
| | - Ian R Griffiths
- School of Veterinary Medicine, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, G12 8TA, UK
| | - James Garbern
- Department of Neurology and Center for Molecular Medicine and Genetics, Wayne State University, Detroit, MI 48201, USA
| | - Gemma Thomson
- School of Veterinary Medicine, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, G12 8TA, UK
| | - Peter Kuzman
- Department of Neuropathology, University Clinic Leipzig, D-04103 Leipzig, Germany
| | - Jennifer A Barrie
- School of Veterinary Medicine, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, G12 8TA, UK.,Institute of Infection, Immunity and Inflammation, University of Glasgow, Glasgow, G12 8TA, UK
| | - Maj-Lis McCulloch
- School of Veterinary Medicine, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, G12 8TA, UK
| | - Jacques Penderis
- School of Veterinary Medicine, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, G12 8TA, UK
| | - Ruth Stassart
- Department of Neuropathology, University Clinic Leipzig, D-04103 Leipzig, Germany
| | - Klaus-Armin Nave
- Max Planck Institute for Experimental Medicine, D-37075 Goettingen, Germany
| | - Julia M Edgar
- School of Veterinary Medicine, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, G12 8TA, UK.,Institute of Infection, Immunity and Inflammation, University of Glasgow, Glasgow, G12 8TA, UK.,Max Planck Institute for Experimental Medicine, D-37075 Goettingen, Germany
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5
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Sase S, Almad AA, Boecker CA, Guedes-Dias P, Li JJ, Takanohashi A, Patel A, McCaffrey T, Patel H, Sirdeshpande D, Curiel J, Shih-Hwa Liu J, Padiath Q, Holzbaur EL, Scherer SS, Vanderver A. TUBB4A mutations result in both glial and neuronal degeneration in an H-ABC leukodystrophy mouse model. eLife 2020; 9:52986. [PMID: 32463361 PMCID: PMC7255805 DOI: 10.7554/elife.52986] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2019] [Accepted: 04/13/2020] [Indexed: 12/20/2022] Open
Abstract
Mutations in TUBB4A result in a spectrum of leukodystrophy including Hypomyelination with Atrophy of Basal Ganglia and Cerebellum (H-ABC), a rare hypomyelinating leukodystrophy, often associated with a recurring variant p.Asp249Asn (D249N). We have developed a novel knock-in mouse model harboring heterozygous (Tubb4aD249N/+) and the homozygous (Tubb4aD249N/D249N) mutation that recapitulate the progressive motor dysfunction with tremor, dystonia and ataxia seen in H-ABC. Tubb4aD249N/D249N mice have myelination deficits along with dramatic decrease in mature oligodendrocytes and their progenitor cells. Additionally, a significant loss occurs in the cerebellar granular neurons and striatal neurons in Tubb4aD249N/D249N mice. In vitro studies show decreased survival and dysfunction in microtubule dynamics in neurons from Tubb4aD249N/D249N mice. Thus Tubb4aD249N/D249N mice demonstrate the complex cellular physiology of H-ABC, likely due to independent effects on oligodendrocytes, striatal neurons, and cerebellar granule cells in the context of altered microtubule dynamics, with profound neurodevelopmental deficits.
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Affiliation(s)
- Sunetra Sase
- Department of Neurology, The Children's Hospital of Philadelphia, Philadelphia, United States
| | - Akshata A Almad
- Department of Neurology, The Children's Hospital of Philadelphia, Philadelphia, United States
| | - C Alexander Boecker
- Department of Physiology, the Perelman School of Medicine, University of Pennsylvania, Philadelphia, United States
| | - Pedro Guedes-Dias
- Department of Physiology, the Perelman School of Medicine, University of Pennsylvania, Philadelphia, United States
| | - Jian J Li
- Department of Neurology, the Perelman School of Medicine, University of Pennsylvania, Philadelphia, United States
| | - Asako Takanohashi
- Department of Neurology, The Children's Hospital of Philadelphia, Philadelphia, United States
| | - Akshilkumar Patel
- Department of Neurology, The Children's Hospital of Philadelphia, Philadelphia, United States
| | - Tara McCaffrey
- Department of Neurology, The Children's Hospital of Philadelphia, Philadelphia, United States
| | - Heta Patel
- Department of Neurology, The Children's Hospital of Philadelphia, Philadelphia, United States
| | - Divya Sirdeshpande
- Department of Neurology, The Children's Hospital of Philadelphia, Philadelphia, United States
| | - Julian Curiel
- Department of Neurology, The Children's Hospital of Philadelphia, Philadelphia, United States
| | - Judy Shih-Hwa Liu
- Department of Neurology, Department of Molecular Biology, Cell Biology, and Biochemistry, Brown University, Providence, United States
| | - Quasar Padiath
- Department of Human Genetics and Neurobiology, University of Pittsburgh, Pittsburgh, United States
| | - Erika Lf Holzbaur
- Department of Physiology, the Perelman School of Medicine, University of Pennsylvania, Philadelphia, United States
| | - Steven S Scherer
- Department of Neurology, the Perelman School of Medicine, University of Pennsylvania, Philadelphia, United States
| | - Adeline Vanderver
- Department of Neurology, The Children's Hospital of Philadelphia, Philadelphia, United States.,Department of Neurology, the Perelman School of Medicine, University of Pennsylvania, Philadelphia, United States
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6
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Curiel J, Rodríguez Bey G, Takanohashi A, Bugiani M, Fu X, Wolf NI, Nmezi B, Schiffmann R, Bugaighis M, Pierson T, Helman G, Simons C, van der Knaap MS, Liu J, Padiath Q, Vanderver A. TUBB4A mutations result in specific neuronal and oligodendrocytic defects that closely match clinically distinct phenotypes. Hum Mol Genet 2018; 26:4506-4518. [PMID: 28973395 DOI: 10.1093/hmg/ddx338] [Citation(s) in RCA: 51] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2017] [Accepted: 08/24/2017] [Indexed: 12/16/2022] Open
Abstract
Hypomyelinating leukodystrophies are heritable disorders defined by lack of development of brain myelin, but the cellular mechanisms of hypomyelination are often poorly understood. Mutations in TUBB4A, encoding the tubulin isoform tubulin beta class IVA (Tubb4a), result in the symptom complex of hypomyelination with atrophy of basal ganglia and cerebellum (H-ABC). Additionally, TUBB4A mutations are known to result in a broad phenotypic spectrum, ranging from primary dystonia (DYT4), isolated hypomyelination with spastic quadriplegia, and an infantile onset encephalopathy, suggesting multiple cell types may be involved. We present a study of the cellular effects of TUBB4A mutations responsible for H-ABC (p.Asp249Asn), DYT4 (p.Arg2Gly), a severe combined phenotype with hypomyelination and encephalopathy (p.Asn414Lys), as well as milder phenotypes causing isolated hypomyelination (p.Val255Ile and p.Arg282Pro). We used a combination of histopathological, biochemical and cellular approaches to determine how these different mutations may have variable cellular effects in neurons and/or oligodendrocytes. Our results demonstrate that specific mutations lead to either purely neuronal, combined neuronal and oligodendrocytic or purely oligodendrocytic defects that closely match their respective clinical phenotypes. Thus, the DYT4 mutation that leads to phenotypes attributable to neuronal dysfunction results in altered neuronal morphology, but with unchanged tubulin quantity and polymerization, with normal oligodendrocyte morphology and myelin gene expression. Conversely, mutations associated with isolated hypomyelination (p.Val255Ile and p.Arg282Pro) and the severe combined phenotype (p.Asn414Lys) resulted in normal neuronal morphology but were associated with altered oligodendrocyte morphology, myelin gene expression, and microtubule dysfunction. The H-ABC mutation (p.Asp249Asn) that exhibits a combined neuronal and myelin phenotype had overlapping cellular defects involving both neuronal and oligodendrocyte cell types in vitro. Only mutations causing hypomyelination phenotypes showed altered microtubule dynamics and acted through a dominant toxic gain of function mechanism. The DYT4 mutation had no impact on microtubule dynamics suggesting a distinct mechanism of action. In summary, the different clinical phenotypes associated with TUBB4A reflect the selective and specific cellular effects of the causative mutations. Cellular specificity of disease pathogenesis is relevant to developing targeted treatments for this disabling condition.
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Affiliation(s)
- Julian Curiel
- Center for Neuroscience Research, Children's National Health System, Children's Research Institute, Washington, DC 20010, USA
| | | | - Asako Takanohashi
- Center for Genetic Medicine Research, Children's National Health System, Children's Research Institute, Washington, DC 20010, USA.,Division of Neurology, Children's Hospital of Philadelphia, Philadelphia, PA 19104, USA
| | | | - Xiaoqin Fu
- Center for Neuroscience Research, Children's National Health System, Children's Research Institute, Washington, DC 20010, USA
| | - Nicole I Wolf
- VU University Medical Center, Amsterdam, The Netherlands
| | - Bruce Nmezi
- Department of Human Genetics, University of Pittsburgh, Pittsburgh, PA 15260, USA
| | - Raphael Schiffmann
- Institute of Metabolic Disease, Baylor Scott & White Research Institute, Dallas, TX 75204, USA
| | - Mona Bugaighis
- Center for Neuroscience Research, Children's National Health System, Children's Research Institute, Washington, DC 20010, USA
| | - Tyler Pierson
- Departments of Pediatrics and Neurology, Cedar Sinai Medical Center, Board of Governors Regenerative Medicine Institute, Los Angeles, CA 90048, USA
| | - Guy Helman
- Center for Genetic Medicine Research, Children's National Health System, Children's Research Institute, Washington, DC 20010, USA.,Institute for Molecular Bioscience, University of Queensland, Brisbane, Australia.,Department of Neurology, Children's National Health System, Washington, DC 20010, USA
| | - Cas Simons
- Institute for Molecular Bioscience, University of Queensland, Brisbane, Australia
| | | | - Judy Liu
- Center for Neuroscience Research, Children's National Health System, Children's Research Institute, Washington, DC 20010, USA
| | - Quasar Padiath
- Department of Human Genetics, University of Pittsburgh, Pittsburgh, PA 15260, USA
| | - Adeline Vanderver
- Center for Genetic Medicine Research, Children's National Health System, Children's Research Institute, Washington, DC 20010, USA.,Division of Neurology, Children's Hospital of Philadelphia, Philadelphia, PA 19104, USA.,Department of Neurology, Children's National Health System, Washington, DC 20010, USA.,Perlman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
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7
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Silva-Gómez AB, Bravo-Duran DA, Eguibar JR, Cortes C. Juvenile Taiep rats have shorter dendritic trees in the dorsal field of the hippocampus without spatial learning disabilities. Synapse 2018; 72:e22024. [PMID: 29323756 DOI: 10.1002/syn.22024] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2017] [Revised: 12/28/2017] [Accepted: 01/08/2018] [Indexed: 12/12/2022]
Abstract
Myelin mutant taiep rats show a progressive demyelination in the central nervous system due to an abnormal accumulation of microtubules in the cytoplasm and the processes on their oligodendrocytes. Demyelination is associated with electrophysiological alterations and the mutant had a progressive astrocytosis. The illness is associated with change in cytokine levels and in the expression of different nitric oxide synthase and concomitantly lipoperoxidation in several areas of the brain. However, until now there has been no detailed anatomical analysis of neurons in this mutant. The aim of this study was to analyze the dendritic morphology in the hippocampus using Golgi-Cox staining and spatial memory through Morris water maze test in young adult (3 months old) taiep rats and compare them with normal Sprague-Dawley. Our results showed that taiep rats have altered dendritic tree morphology in pyramidal neurons in the CA1 field of the hippocampus, but not in the CA3 region. These morphological changes did not produce a concomitant deficit in spatial memory acquisition or recall at this early stage of the disease. Our results suggest that impairment of dendritic morphology in the CA1 field of the hippocampus is a landmark of the pathology of this progressive multiple sclerosis model.
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Affiliation(s)
| | | | - Jose R Eguibar
- Institute of Physiology, Benemérita Universidad Autónoma de Puebla, México.,Research Office, Vice-rectory of Research and Postgraduate Studies, Benemérita Universidad Autónoma de Puebla, México
| | - Carmen Cortes
- Institute of Physiology, Benemérita Universidad Autónoma de Puebla, México
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8
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Duncan ID, Bugiani M, Radcliff AB, Moran JJ, Lopez-Anido C, Duong P, August BK, Wolf NI, van der Knaap MS, Svaren J. A mutation in the Tubb4a gene leads to microtubule accumulation with hypomyelination and demyelination. Ann Neurol 2017; 81:690-702. [PMID: 28393430 DOI: 10.1002/ana.24930] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2017] [Revised: 04/03/2017] [Accepted: 04/03/2017] [Indexed: 01/08/2023]
Abstract
OBJECTIVE Our goal was to define the genetic cause of the profound hypomyelination in the taiep rat model and determine its relevance to human white matter disease. METHODS Based on previous localization of the taiep mutation to rat chromosome 9, we tested whether the mutation resided within the Tubb4a (β-tubulin 4A) gene, because mutations in the TUBB4A gene have been described in patients with central nervous system hypomyelination. To determine whether accumulation of microtubules led to progressive demyelination, we analyzed the spinal cord and optic nerves of 2-year-old rats by light and electron microscopy. Cerebral white matter from a patient with TUBB4A Asn414Lys mutation and magnetic resonance imaging evidence of severe hypomyelination were studied similarly. RESULTS As the taiep rat ages, there is progressive loss of myelin in the brain and dorsal column of the spinal cord associated with increased oligodendrocyte numbers with accumulation of microtubules. This accumulation involved the entire cell body and distal processes of oligodendrocytes, but there was no accumulation of microtubules in axons. A single point mutation in Tubb4a (p.Ala302Thr) was found in homozygous taiep samples. A similar hypomyelination associated with increased oligodendrocyte numbers and arrays of microtubules in oligodendrocytes was demonstrated in the human patient sample. INTERPRETATION The taiep rat is the first animal model of TUBB4 mutations in humans and a novel system in which to test the mechanism of microtubule accumulation. The finding of microtubule accumulation in a patient with a TUBB4A mutation and leukodystrophy confirms the usefulness of taiep as a model of the human disease. Ann Neurol 2017;81:690-702.
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Affiliation(s)
- Ian D Duncan
- Department of Medical Sciences, University of Wisconsin-Madison, Madison, WI
| | - Marianna Bugiani
- Department of Pathology, VU University Medical Center, Amsterdam, the Netherlands.,Center for Childhood White Matter Disorders, Amsterdam Neuroscience, VU University Medical Center, Amsterdam, the Netherlands
| | - Abigail B Radcliff
- Department of Medical Sciences, University of Wisconsin-Madison, Madison, WI
| | - John J Moran
- Waisman Center, University of Wisconsin-Madison, Madison, WI
| | | | - Phu Duong
- Waisman Center, University of Wisconsin-Madison, Madison, WI
| | - Benjamin K August
- Electron Microscope Facility, School of Medicine and Public Health, University of Wisconsin-Madison, Madison, WI
| | - Nicole I Wolf
- Center for Childhood White Matter Disorders, Amsterdam Neuroscience, VU University Medical Center, Amsterdam, the Netherlands.,Department of Child Neurology, VU University Medical Center, Amsterdam, the Netherlands
| | - Marjo S van der Knaap
- Center for Childhood White Matter Disorders, Amsterdam Neuroscience, VU University Medical Center, Amsterdam, the Netherlands.,Department of Child Neurology, VU University Medical Center, Amsterdam, the Netherlands.,Department of Functional Genomics, Center for Neurogenomics and Cognitive Research, Amsterdam Neuroscience, VU University, Amsterdam, the Netherlands
| | - John Svaren
- Waisman Center, University of Wisconsin-Madison, Madison, WI.,Department of Comparative Biosciences, School of Veterinary Medicine, University of Wisconsin-Madison, Madison, WI
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9
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Maggipinto MJ, Ford J, Le KH, Tutolo JW, Furusho M, Wizeman JW, Bansal R, Barbarese E. Conditional knockout of TOG results in CNS hypomyelination. Glia 2017; 65:489-501. [PMID: 28063167 DOI: 10.1002/glia.23106] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2016] [Revised: 10/29/2016] [Accepted: 11/30/2016] [Indexed: 12/12/2022]
Abstract
The tumor overexpressed gene (TOG) protein is present in RNA granules that transport myelin basic protein (MBP) mRNA in oligodendrocyte processes to the myelin compartment. Its role was investigated by conditionally knocking it out (KO) in myelinating glia in vivo. TOG KO mice have severe motor deficits that are already apparent at the time of weaning. This phenotype correlates with a paucity of myelin in several CNS regions, the most severe being in the spinal cord. In the TOG KO optic nerve <30% of axons are myelinated. The number of oligodendrocytes in the corpus callosum, cerebellum, and cervical spinal cord is normal. In the absence of TOG, the most patent biochemical change is a large reduction in MBP content, yet normal amounts of MBP transcripts are found in the brain of affected animals. MBP transcripts are largely confined to the cell body of the oligodendrocytes in the TOG KO in contrast to the situation in wild type mice where they are found in the processes of the oligodendrocytes and in the myelin compartment. These findings indicate that MBP gene expression involves a post-transcriptional TOG-dependent step. TOG may be necessary for MBP mRNA assembly into translation permissive granules, and/or for transport to preferred sites of translation. GLIA 2017;65:489-501.
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Affiliation(s)
- Michael J Maggipinto
- Department of Neuroscience, University of Connecticut School of Medicine, Farmington, Connecticut
| | - Joshay Ford
- Department of Neuroscience, University of Connecticut School of Medicine, Farmington, Connecticut
| | - Kristine H Le
- Department of Neuroscience, University of Connecticut School of Medicine, Farmington, Connecticut
| | - Jessica W Tutolo
- Department of Neuroscience, University of Connecticut School of Medicine, Farmington, Connecticut
| | - Miki Furusho
- Department of Neuroscience, University of Connecticut School of Medicine, Farmington, Connecticut
| | - John W Wizeman
- Department of Neuroscience, University of Connecticut School of Medicine, Farmington, Connecticut
| | - Rashmi Bansal
- Department of Neuroscience, University of Connecticut School of Medicine, Farmington, Connecticut
| | - Elisa Barbarese
- Department of Neuroscience, University of Connecticut School of Medicine, Farmington, Connecticut
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10
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Thakurela S, Garding A, Jung RB, Müller C, Goebbels S, White R, Werner HB, Tiwari VK. The transcriptome of mouse central nervous system myelin. Sci Rep 2016; 6:25828. [PMID: 27173133 PMCID: PMC4865983 DOI: 10.1038/srep25828] [Citation(s) in RCA: 53] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2016] [Accepted: 04/21/2016] [Indexed: 01/03/2023] Open
Abstract
Rapid nerve conduction in the CNS is facilitated by insulation of axons with myelin, a specialized oligodendroglial compartment distant from the cell body. Myelin is turned over and adapted throughout life; however, the molecular and cellular basis of myelin dynamics remains elusive. Here we performed a comprehensive transcriptome analysis (RNA-seq) of myelin biochemically purified from mouse brains at various ages and find a surprisingly large pool of transcripts enriched in myelin. Further computational analysis showed that the myelin transcriptome is closely related to the myelin proteome but clearly distinct from the transcriptomes of oligodendrocytes and brain tissues, suggesting a highly selective incorporation of mRNAs into the myelin compartment. The mRNA-pool in myelin displays maturation-dependent dynamic changes of composition, abundance, and functional associations; however ageing-dependent changes after 6 months were minor. We suggest that this transcript pool enables myelin turnover and the local adaptation of individual pre-existing myelin sheaths.
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Affiliation(s)
| | - Angela Garding
- Institute of Molecular Biology (IMB), 55128 Mainz, Germany
| | - Ramona B. Jung
- Department of Neurogenetics, Max Planck Institute of Experimental Medicine, 37075 Göttingen, Germany
| | - Christina Müller
- Institute of Physiology, University Medical Center of the Johannes Gutenberg-University, 55128 Mainz, Germany
| | - Sandra Goebbels
- Department of Neurogenetics, Max Planck Institute of Experimental Medicine, 37075 Göttingen, Germany
| | - Robin White
- Institute of Physiology, University Medical Center of the Johannes Gutenberg-University, 55128 Mainz, Germany
| | - Hauke B. Werner
- Department of Neurogenetics, Max Planck Institute of Experimental Medicine, 37075 Göttingen, Germany
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11
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Duncan ID, Radcliff AB. Inherited and acquired disorders of myelin: The underlying myelin pathology. Exp Neurol 2016; 283:452-75. [PMID: 27068622 PMCID: PMC5010953 DOI: 10.1016/j.expneurol.2016.04.002] [Citation(s) in RCA: 77] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2016] [Revised: 04/01/2016] [Accepted: 04/04/2016] [Indexed: 01/26/2023]
Abstract
Remyelination is a major therapeutic goal in human myelin disorders, serving to restore function to demyelinated axons and providing neuroprotection. The target disorders that might be amenable to the promotion of this repair process are diverse and increasing in number. They range primarily from those of genetic, inflammatory to toxic origin. In order to apply remyelinating strategies to these disorders, it is essential to know whether the myelin damage results from a primary attack on myelin or the oligodendrocyte or both, and whether indeed these lead to myelin breakdown and demyelination. In some disorders, myelin sheath abnormalities are prominent but demyelination does not occur. This review explores the range of human and animal disorders where myelin pathology exists and focusses on defining the myelin changes in each and their cause, to help define whether they are targets for myelin repair therapy. We reviewed myelin disorders of the CNS in humans and animals. Myelin damage results from primary attack on the oligodendrocyte or myelin sheath. All major categories of disease can affect CNS myelin. Myelin vacuolation is common, yet does not always result in demyelination.
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Affiliation(s)
- Ian D Duncan
- Department of Medical Sciences, School of Veterinary Medicine, University of Wisconsin-Madison, Madison, WI, United States.
| | - Abigail B Radcliff
- Department of Medical Sciences, School of Veterinary Medicine, University of Wisconsin-Madison, Madison, WI, United States
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12
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Pemberton TJ, Choi S, Mayer JA, Li FY, Gokey N, Svaren J, Safra N, Bannasch DL, Sullivan K, Breuhaus B, Patel PI, Duncan ID. A mutation in the canine gene encoding folliculin-interacting protein 2 (FNIP2) associated with a unique disruption in spinal cord myelination. Glia 2014; 62:39-51. [PMID: 24272703 DOI: 10.1002/glia.22582] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2013] [Revised: 08/29/2013] [Accepted: 09/17/2013] [Indexed: 12/12/2022]
Abstract
Novel mutations in myelin and myelin-associated genes have provided important information on oligodendrocytes and myelin and the effects of their disruption on the normal developmental process of myelination of the central nervous system (CNS). We report here a mutation in the folliculin-interacting protein 2 (FNIP2) gene in the Weimaraner dog that results in hypomyelination of the brain and a tract-specific myelin defect in the spinal cord. This myelination disruption results in a notable tremor syndrome from which affected dogs recover with time. In the peripheral tracts of the lateral and ventral columns of the spinal cord, there is a lack of mature oligodendrocytes. A genome-wide association study of DNA from three groups of dogs mapped the gene to canine chromosome 15. Sequencing of all the genes in the candidate region identified a frameshift mutation in the FNIP2 gene that segregated with the phenotype. While the functional role of FNIP2 is not known, our data would suggest that production of truncated protein results in a delay or failure of maturation of a subpopulation of oligodendrocytes.
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Affiliation(s)
- Trevor J Pemberton
- Institute for Genetic Medicine, Keck School of Medicine of USC, University of Southern California, Los Angeles, California.,Department of Biochemistry and Medical Genetics, University of Manitoba, Winnipeg, Manitoba, Canada
| | - Sunju Choi
- Institute for Genetic Medicine, Keck School of Medicine of USC, University of Southern California, Los Angeles, California
| | - Joshua A Mayer
- Department of Medical Sciences, School of Veterinary Medicine, University of Wisconsin-Madison, Madison, Wisconsin
| | - Fang-Yuan Li
- Institute for Genetic Medicine, Keck School of Medicine of USC, University of Southern California, Los Angeles, California.,Department of Medical Sciences, School of Veterinary Medicine, University of Wisconsin-Madison, Madison, Wisconsin
| | - Nolan Gokey
- Department of Comparative Biosciences, School of Veterinary Medicine, University of Wisconsin-Madison, Madison, Wisconsin
| | - John Svaren
- Department of Comparative Biosciences, School of Veterinary Medicine, University of Wisconsin-Madison, Madison, Wisconsin
| | - Noa Safra
- Department of Population Health and Reproduction, School of Veterinary Medicine, University of California Davis, Davis, California
| | - Danika L Bannasch
- Department of Population Health and Reproduction, School of Veterinary Medicine, University of California Davis, Davis, California
| | - Katrina Sullivan
- Department of Medicine, University of Washington, Seattle, Washington
| | - Babetta Breuhaus
- College of Veterinary Science, North Carolina State University, Raleigh, North Carolina
| | - Pragna I Patel
- Institute for Genetic Medicine, Keck School of Medicine of USC, University of Southern California, Los Angeles, California.,Division of Biomedical Sciences, Herman Ostrow School of Dentistry of USC, University of Southern California, Los Angeles, California
| | - Ian D Duncan
- Department of Medical Sciences, School of Veterinary Medicine, University of Wisconsin-Madison, Madison, Wisconsin
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13
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Tanaka M, Izawa T, Yamate J, Franklin RJM, Kuramoto T, Serikawa T, Kuwamura M. The VF rat with abnormal myelinogenesis has a mutation in Dopey1. Glia 2014; 62:1530-42. [PMID: 24863653 DOI: 10.1002/glia.22698] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2014] [Revised: 04/30/2014] [Accepted: 05/07/2014] [Indexed: 11/09/2022]
Abstract
The vacuole formation (VF) rat is an autosomal recessive myelin mutant characterized by generalized tremor, hypomyelination, and periaxonal vacuole formation of the central nervous system (CNS). Here, we report the most likely causative gene for neurological disease in the VF rat and pursue its roles in the development and maintenance of the CNS myelin. We identified a nonsense mutation in the dopey family member 1 (Dopey1) located on rat chromosome 8. Expression level of Dopey1 mRNA was decreased and DOPEY1 protein was undetectable both in the white and gray matter of the spinal cords in the VF rats. Double immunohistochemistry demonstrated that DOPEY1 was mainly expressed in neurons and oligodendrocytes in the wild-type rats, whereas no positive cells were detected in the VF rats. We also demonstrated a marked reduction in myelin components both at mRNA and protein levels during myelinogenesis in the VF rats. In addition, proteolipid protein and myelin-associated glycoprotein accumulated in oligodendrocyte cell body, suggesting that Dopey1 is likely to be involved in the traffic of myelin components. Our results highlighted the importance of Dopey1 for the development and maintenance of the CNS myelin.
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Affiliation(s)
- Miyuu Tanaka
- Laboratory of Veterinary Pathology, Osaka Prefecture University, Izumisano, Osaka, 598-8531, Japan
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14
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Espinosa-Jeffrey A, Paez PM, Cheli VT, Spreuer V, Wanner I, de Vellis J. Impact of simulated microgravity on oligodendrocyte development: implications for central nervous system repair. PLoS One 2013; 8:e76963. [PMID: 24324574 PMCID: PMC3850904 DOI: 10.1371/journal.pone.0076963] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2013] [Accepted: 08/28/2013] [Indexed: 01/11/2023] Open
Abstract
We have recently established a culture system to study the impact of simulated microgravity on oligodendrocyte progenitor cells (OPCs) development. We subjected mouse and human OPCs to a short exposure of simulated microgravity produced by a 3D-Clinostat robot. Our results demonstrate that rodent and human OPCs display enhanced and sustained proliferation when exposed to simulated microgravity as assessed by several parameters, including a decrease in the cell cycle time. Additionally, OPC migration was examined in vitro using time-lapse imaging of cultured OPCs. Our results indicated that OPCs migrate to a greater extent after stimulated microgravity than in normal conditions, and this enhanced motility was associated with OPC morphological changes. The lack of normal gravity resulted in a significant increase in the migration speed of mouse and human OPCs and we found that the average leading process in migrating bipolar OPCs was significantly longer in microgravity treated cells than in controls, demonstrating that during OPC migration the lack of gravity promotes leading process extension, an essential step in the process of OPC migration. Finally, we tested the effect of simulated microgravity on OPC differentiation. Our data showed that the expression of mature oligodendrocyte markers was significantly delayed in microgravity treated OPCs. Under conditions where OPCs were allowed to progress in the lineage, simulated microgravity decreased the proportion of cells that expressed mature markers, such as CC1 and MBP, with a concomitant increased number of cells that retained immature oligodendrocyte markers such as Sox2 and NG2. Development of methodologies aimed at enhancing the number of OPCs and their ability to progress on the oligodendrocyte lineage is of great value for treatment of demyelinating disorders. To our knowledge, this is the first report on the gravitational modulation of oligodendrocyte intrinsic plasticity to increase their progenies.
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Affiliation(s)
- Araceli Espinosa-Jeffrey
- Semel Institute for Neuroscience and Human Behavior, David Geffen School of Medicine at UCLA, Intellectual and Developmental Disabilities Research Center, Los Angeles, California, United States of America
- * E-mail:
| | - Pablo M. Paez
- Hunter James Kelly Research Institute, Department of Pharmacology and Toxicology, School of Medicine and Biomedical Sciences, SUNY at Buffalo, NYS Center of Excellence, Buffalo, New York, United States of America
| | - Veronica T. Cheli
- Hunter James Kelly Research Institute, Department of Pharmacology and Toxicology, School of Medicine and Biomedical Sciences, SUNY at Buffalo, NYS Center of Excellence, Buffalo, New York, United States of America
| | - Vilma Spreuer
- Hunter James Kelly Research Institute, Department of Pharmacology and Toxicology, School of Medicine and Biomedical Sciences, SUNY at Buffalo, NYS Center of Excellence, Buffalo, New York, United States of America
| | - Ina Wanner
- Semel Institute for Neuroscience and Human Behavior, David Geffen School of Medicine at UCLA, Intellectual and Developmental Disabilities Research Center, Los Angeles, California, United States of America
| | - Jean de Vellis
- Semel Institute for Neuroscience and Human Behavior, David Geffen School of Medicine at UCLA, Intellectual and Developmental Disabilities Research Center, Los Angeles, California, United States of America
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15
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Myelin Proteome Analysis: Methods and Implications for the Myelin Cytoskeleton. THE CYTOSKELETON 2013. [DOI: 10.1007/978-1-62703-266-7_15] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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16
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Eguibar JR, del Carmen Cortes M, Lara-Lozano M, Mendiola DM. Dopaminergic D2-like agonists produce yawning in the myelin mutant taiep and Sprague–Dawley rats. Pharmacol Biochem Behav 2012; 102:118-23. [DOI: 10.1016/j.pbb.2012.03.020] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/23/2011] [Revised: 03/01/2012] [Accepted: 03/25/2012] [Indexed: 11/29/2022]
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17
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Duncan ID, Kondo Y, Zhang SC. The myelin mutants as models to study myelin repair in the leukodystrophies. Neurotherapeutics 2011; 8:607-24. [PMID: 21979830 PMCID: PMC3250297 DOI: 10.1007/s13311-011-0080-y] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
The leukodystrophies are rare and serious genetic disorders of the central nervous system that primarily affect children who frequently die early in life or have significantly delayed motor and mental milestones that result in long-term disability. Although with some of these disorders, early intervention with bone marrow or cord blood transplantation has been proven useful, it has not yet been determined that such therapies promote myelin repair of the central nervous system. Research on experimental therapies aimed at myelin repair is aided by the ability to test cell replacement strategies in genetic models in which the mutations and neuropathology match the human disorder. Thus, models exist of Pelizaeus-Merzbacher disease and the lysosomal storage disorder, Krabbe disease, which reflect the clinical and pathological course of the human disorders. Collectively, animals with mutations in myelin genes are called the myelin mutants, and they include rodent models such as the shiverer mouse that have been extensively used to study myelination by exogenous cell transplantation. These studies have encompassed many permutations of the age of the recipient, type of transplanted cell, site of engraftment, and so forth, and they offer hope that the scaling up of myelin produced by transplanted cells will have clinical significance in treating patients. Here we review these models and discuss their relative importance and use in such translational approaches. We discuss how grafts are identified and functional outcomes are measured. Finally, we briefly discuss the cells that have been successfully transplanted, which may be used in future clinical trials.
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Affiliation(s)
- Ian D Duncan
- Department of Medical Sciences, School of Veterinary Medicine, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA.
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18
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Slowly Progressive Axonal Degeneration in a Rat Model of Chronic, Nonimmune-Mediated Demyelination. J Neuropathol Exp Neurol 2010; 69:1256-69. [DOI: 10.1097/nen.0b013e3181ffc317] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
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19
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Eguibar JR, Cortés MDC, Lara-Lozano M. Presynaptic dopaminergic agonists increased gripping-generated immobility episodes in the myelin-mutant taiep rat. Neurosci Lett 2010; 483:189-92. [DOI: 10.1016/j.neulet.2010.07.086] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2010] [Revised: 07/29/2010] [Accepted: 07/31/2010] [Indexed: 11/26/2022]
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20
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Bauer NG, Richter-Landsberg C, Ffrench-Constant C. Role of the oligodendroglial cytoskeleton in differentiation and myelination. Glia 2010; 57:1691-705. [PMID: 19455583 DOI: 10.1002/glia.20885] [Citation(s) in RCA: 141] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Oligodendrocytes, the myelin-forming cells of the central nervous system, are in culture characterized by an elaborate process network, terminating in flat membranous sheets that are rich in myelin-specific proteins and lipids, and spirally wrap axons forming a compact insulating layer in vivo. By analogy with other cell types, maintenance and stability of these processes, as well as the formation of the myelin sheath, likely rely on a pronounced cytoskeleton consisting of microtubules and microfilaments. While the specialized process of wrapping and compaction forming the myelin sheath is not well understood, considerably more is known about how cytoskeletal organization is mediated by extracellular and intracellular signals and other interaction partners during oligodendrocyte differentiation and myelination. Here, we review the current state of knowledge on the role of the oligodendrocyte cytoskeleton in differentiation with an emphasis on signal transduction mechanisms and will attempt to draw out implications for its significance in myelination.
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Affiliation(s)
- Nina G Bauer
- MRC Centre for Regenerative Medicine, Centre for Multiple Sclerosis Research, The University of Edinburgh, Queen's Medical Research Institute, Edinburgh EH16 4TJ, United Kingdom.
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21
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Eguibar JR, Cortés M, Ita M. Serotonergic-postsynaptic receptors modulate gripping-induced immobility episodes in maletaieprats. Synapse 2009; 63:737-44. [DOI: 10.1002/syn.20655] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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22
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Ita ML, Cortés MDC, Valencia J, Eguibar JR. Activation of serotonin 5-HT1-receptors decreased gripping-induced immobility episodes in taiep rats. Neurosci Lett 2009; 449:147-50. [DOI: 10.1016/j.neulet.2008.10.088] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2008] [Revised: 10/21/2008] [Accepted: 10/28/2008] [Indexed: 10/21/2022]
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23
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Belkadi A, LoPresti P. Truncated Tau with the Fyn-binding domain and without the microtubule-binding domain hinders the myelinating capacity of an oligodendrocyte cell line. J Neurochem 2008; 107:351-60. [PMID: 18680553 DOI: 10.1111/j.1471-4159.2008.05600.x] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
The mechanisms underlying developmental myelination have therapeutic potential following CNS injury and degeneration. We report that transplanted central glial (CG)-4 cells had a diminished myelinating capacity in myelin-deficient (md) rats when cells express a mutated form of Tau (Tau [688]), which binds Fyn but not the microtubules. In the brain of the md rats, Tau [688]-transfected CG-4 cells displayed a decrease in cellular process outgrowth and myelination; in the spinal cord the extent of myelination rostral and caudal to the injection site was decreased. In contrast, control Tau [605]-transfected CG-4 cells formed long cellular processes and substantial areas of myelin both in the brain and spinal cord. In culture, Tau [688]-transfected CG-4 cells displayed a decrease in cellular process outgrowth, and Fyn localized largely in the cell body, not the processes. Thus, Tau in oligodendrocytes plays a key role in myelination, and a functional Tau-Fyn interaction might have therapeutic potential during demyelination and myelin repair following CNS injury and degeneration.
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Affiliation(s)
- Abdelmadjid Belkadi
- Department of Medical Science, School of Veterinary Medicine, University of Wisconsin, Madison, Wisconsin, USA
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24
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Izawa T, Takenaka S, Ihara H, Kotani T, Yamate J, Franklin RJ, Kuwamura M. Cellular responses in the spinal cord during development of hypomyelination in the mv rat. Brain Res 2008; 1195:120-9. [DOI: 10.1016/j.brainres.2007.12.022] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2007] [Revised: 12/10/2007] [Accepted: 12/12/2007] [Indexed: 10/22/2022]
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25
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Abstract
The myelin-associated glycoprotein (MAG) is a type I transmembrane glycoprotein localized in periaxonal Schwann cell and oligodendroglial membranes of myelin sheaths where it functions in glia-axon interactions. It contains five immunoglobulin (Ig)-like domains and is in the sialic acid-binding subgroup of the Ig superfamily. It appears to function both as a ligand for an axonal receptor that is needed for the maintenance of myelinated axons and as a receptor for an axonal signal that promotes the differentiation, maintenance and survival of oligodendrocytes. Its function in the maintenance of myelinated axons may be related to its role as one of the white matter inhibitors of neurite outgrowth acting through a receptor complex involving the Nogo receptor and/or gangliosides containing 2,3-linked sialic acid. MAG is expressed as two developmentally regulated isoforms with different cytoplasmic domains that may activate different signal transduction pathways in myelin-forming cells. MAG contains a carbohydrate epitope shared with other glycoconjugates that is a target antigen in autoimmune peripheral neuropathy associated with IgM gammopathy and has been implicated in a dying back oligodendrogliopathy in multiple sclerosis.
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Affiliation(s)
- Richard H Quarles
- Myelin and Brain Development Section, National Institute of Neurological Disorders and Stroke, NIH, Bethesda, Maryland 20892, USA.
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26
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Cortés MDC, Arias-Montaño JA, Eguibar JR. Prazosin increases immobility episodes in taiep rats without changes in the properties of α1 receptors. Neurosci Lett 2007; 412:159-62. [PMID: 17194536 DOI: 10.1016/j.neulet.2006.10.048] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2006] [Revised: 10/31/2006] [Accepted: 10/31/2006] [Indexed: 11/24/2022]
Abstract
The taiep rat is a myelin mutant in which immobility episodes (IEs) can be induced in adult males by gripping. EEG recordings during gripping-induced IEs show a rapid eye movement (REM) sleep-like pattern, similar to that reported for narcolepsy-cataplexy suggesting that IEs represent a disorder of REM-sleep. An alpha(2) adrenoceptor agonist increases gripping-induced IEs, whereas alpha(2) antagonists decrease these. We have studied the effect of prazosin on IEs and the levels of alpha(1) adrenoceptors were evaluated in cerebro-cortical homogenates of taiep and control rats. Systemic administration of prazosin results in a significant increase in both the frequency and duration of gripping-induced IEs. Our results show that cerebro-cortical tissue is not an adequate candidate for the expression of cataplexy-like symptoms, but prazosin, an alpha(1) antagonist, is a potent inducer of gripping-induced immobility episodes in taiep rats.
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Affiliation(s)
- Ma-del-Carmen Cortés
- Instituto de Fisiología and Secretaría General, Benemérita Universidad Autónoma de Puebla, Apdo. Postal 5-66, C.P. 72430 Puebla, Pue., México
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27
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Leon-Chavez BA, Aguilar-Alonso P, Gonzalez-Barrios JA, Eguibar JR, Ugarte A, Brambila E, Ruiz-Arguelles A, Martinez-Fong D. Increased nitric oxide levels and nitric oxide synthase isoform expression in the cerebellum of the taiep rat during its severe demyelination stage. Brain Res 2006; 1121:221-30. [PMID: 17022950 DOI: 10.1016/j.brainres.2006.08.097] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2006] [Revised: 08/23/2006] [Accepted: 08/25/2006] [Indexed: 11/21/2022]
Abstract
We have previously reported progressive reactive astrocytes in the cerebellum of taiep rats, one of the most regions affected by demyelination, and activation of cerebellar glial cells in vitro. Based on the hypothesis that activated glial cells produce high levels of reactive nitrogen intermediates, we assessed the production of nitric oxide (NO) and the expression of the three NO synthases (NOS) in the cerebellum of 6-month-old taiep rats. A significant 40% increase of NO levels was measured in taiep rats when compared with controls. The protein and mRNA levels of the three NOS isoforms were also significantly increased. In contrast to controls, immunostaining assays against nNOS or iNOS showed an increased number of immunoreactive glial cells in the granular layer (nNOS) and Purkinje layer (iNOS) of cerebellum of taiep rats. Microglia-macrophages and both CD4- and CD8-immunoreactive cells were observed in cerebellar white matter of taiep rats only, thus suggesting other possible cell sources of those NOSs. Differences in the cellular location for eNOS immunoreactivity were not observed. The enhanced levels of NO, NOS proteins, mRNAs, and NOS immunoreactivities in glial cells and microglia strongly suggest glial activation together with the professional immune cells can aggravate the demyelination of aged taiep rats.
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Affiliation(s)
- Bertha Alicia Leon-Chavez
- Facultad de Ciencias Químicas, BUAP, 14 sur y Av. San Claudio, Edif. 138, San Claudio, 72570 Puebla, Pue., México
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28
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Franco-Pons N, Virgos C, Vogel WF, Ureña JM, Soriano E, del Rio JA, Vilella E. Expression of discoidin domain receptor 1 during mouse brain development follows the progress of myelination. Neuroscience 2006; 140:463-75. [PMID: 16603319 DOI: 10.1016/j.neuroscience.2006.02.033] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2005] [Revised: 02/06/2006] [Accepted: 02/10/2006] [Indexed: 11/27/2022]
Abstract
Discoidin domain receptor 1 is a tyrosine kinase receptor expressed in a variety of tissues including the brain. This study describes mRNA and protein expression of discoidin domain receptor 1 in mouse brain during development and provides new insights into its role during gliogenesis and neurogenesis. We performed in situ hybridization for discoidin domain receptor 1 in mouse brains at embryonic day 18, postnatal days 5, 9, 15, 21 and adulthood and observed a diffuse pattern in the proliferative areas during embryogenesis. From postnatal day 5 onwards, a defined cellular expression pattern of discoidin domain receptor 1 was observed, mainly located in white matter tracts and following a spatio-temporal pattern that overlapped the progress of myelination. Next, we performed double-labeling reactions (in situ hybridization followed by immunohistochemistry) that confirmed that discoidin domain receptor 1 was expressed by mature oligodendrocytes. We observed that cells positive for discoidin domain receptor 1 also expressed carnosine and anti-adenomatous polyposis coli, two mature oligodendrocyte markers. Based on the localization of discoidin domain receptor 1 specifically in the white matter fiber tracts during postnatal development, we suggest that discoidin domain receptor 1 participates in the development and maintenance of the myelin sheath.
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Affiliation(s)
- N Franco-Pons
- Unitat de Psiquiatria i Psicologia Mèdica, Facultat de Medicina i Ciències de la Salut, Universitat Rovira i Virgili, and Departament de Formació i Investigació, Hospital Psiquiàtric Universitari Institut Pere Mata, Reus, Spain
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Eguibar JR, Cortés MDC, Valencia J, Arias-Montaño JA. α2 Adrenoceptors are involved in the regulation of the gripping-induced immobility episodes intaiep rats. Synapse 2006; 60:362-70. [PMID: 16838363 DOI: 10.1002/syn.20305] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
In 1989 Holmgren et al. (Holmgren et al. 1989 Lab Anim Sci 39:226-228) described a new mutant rat that developed a progressive motor disturbance during its lifespan. The syndrome is characterized by a tremor in the hind limbs followed by ataxia, episodes of tonic immobility, epilepsy, and paralysis. The acronym of these symptoms (taiep) became the name of this autosomic, recessive mutant rat. The taiep rats are neurological mutant animals with a hypomyelination, followed by a progressive demyelination process. At 7-8 months of age, taiep rats develop immobility episodes (IEs) characterized by a cortical desynchronization, associated with the theta rhythm in the hippocampus and changes of the nucal electromyogram (EMG), whose pattern is like rapid-eye-movement (REM) sleep. These rats also show an altered sleep pattern with an equal REM sleep distribution. This study analyzed therole of alpha(2) adrenoceptors in the expression of gripping-induced IEs in 8-month-old male taiep rats. The alpha(2) adrenoceptor agonists clonidine and xylacine increased the frequency of gripping-induced IEs whereas the alpha(2) antagonists yohimbine and idazoxandecreased or prevented such episodes. These findings correlate with the pharmacological observations in narcoleptic dogs and humans in which alpha(2) adrenergic mechanisms are involved in the modulation of cataplexy. Unexpectedly, the repetitive administration of clonidine resulted in jumping behavior, indicative of phasic activation of extensor musculature. Taken together, our results show that alpha(2) adrenoceptors are involved in the modulation in gripping-induced IEs and after the administration of several doses of clonidine produced phasic motor activation.
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MESH Headings
- Adrenergic alpha-2 Receptor Agonists
- Adrenergic alpha-2 Receptor Antagonists
- Adrenergic alpha-Agonists/pharmacology
- Adrenergic alpha-Antagonists/pharmacology
- Animals
- Behavior, Animal/drug effects
- Behavior, Animal/physiology
- Binding, Competitive/physiology
- Brain/drug effects
- Brain/metabolism
- Brain/physiopathology
- Cataplexy/genetics
- Cataplexy/metabolism
- Cataplexy/physiopathology
- Cerebral Cortex/drug effects
- Cerebral Cortex/metabolism
- Cerebral Cortex/physiopathology
- Demyelinating Diseases/complications
- Demyelinating Diseases/genetics
- Demyelinating Diseases/physiopathology
- Disease Models, Animal
- Movement Disorders/genetics
- Movement Disorders/metabolism
- Movement Disorders/physiopathology
- Norepinephrine/metabolism
- Radioligand Assay
- Rats
- Rats, Mutant Strains
- Rats, Sprague-Dawley
- Receptors, Adrenergic, alpha-2/genetics
- Sleep, REM/drug effects
- Sleep, REM/genetics
- Wakefulness/drug effects
- Wakefulness/genetics
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Affiliation(s)
- José R Eguibar
- Instituto de Fisiología, Benemérita Universidad Autónoma de Puebla, México.
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Roncagliolo M, Schlageter C, León C, Couve E, Bonansco C, Eguibar JR. Developmental impairment of compound action potential in the optic nerve of myelin mutant taiep rats. Brain Res 2005; 1067:78-84. [PMID: 16360123 DOI: 10.1016/j.brainres.2005.10.010] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2005] [Revised: 09/30/2005] [Accepted: 10/04/2005] [Indexed: 10/25/2022]
Abstract
The taiep rat is a myelin mutant with an initial hypomyelination, followed by a progressive demyelination of the CNS. The neurological correlates start with tremor, followed by ataxia, immobility episodes, epilepsy and paralysis. The optic nerve, an easily-isolable central tract fully myelinated by oligodendrocytes, is a suitable preparation to evaluate the developmental impairment of central myelin. We examined the ontogenic development of optic nerve compound action potentials (CAP) throughout the first 6 months of life of control and taiep rats. Control optic nerves (ON) develop CAPs characterized by three waves. Along the first month, the CAPs of taiep rats showed a delayed maturation, with lower amplitudes and longer latencies than controls; at P30, the conduction velocity has only a third of the normal value. Later, as demyelination proceeds, the conduction velocity of taiep ONs begins to decrease and CAPs undergo a gradual temporal dispersion. CAPs of control and taiep showed differences in their pharmacological sensitivity to TEA and 4-AP, two voltage dependent K+ channel-blockers. As compared with TEA, 4-AP induced a significant increase of the amplitudes and a remarkable broadening of CAPs. After P20, unlike controls, the greater sensitivity to 4-AP exhibited by taiep ONs correlates with the detachment and retraction of paranodal loops suggesting that potassium conductances could regulate the excitability as demyelination of CNS axons progresses. It is concluded that the taiep rat, a long-lived mutant, provides a useful model to study the consequences of partial demyelination and the mechanisms by which glial cells regulate the molecular organization and excitability of axonal membranes during development and disease.
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Affiliation(s)
- Manuel Roncagliolo
- Departamento de Fisiología, Facultad de Ciencias, Universidad de Valparaíso, Casilla 5030, Valparaíso, Chile.
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Song J, Goetz BD, Duncan ID. His36Pro point-mutated proteolipid protein retained in the endoplasmic reticulum of oligodendrocytes in theShaking pup. Glia 2005; 53:257-65. [PMID: 16265668 DOI: 10.1002/glia.20279] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The shaking pup (shp) is a canine mutation that affects the myelin protein proteolipid protein (PLP) and its smaller and less abundant isoform, DM20, with proline replacing histidine(36), resulting in a severe myelin deficiency in the central nervous system. We present evidence that the mutation leads to disrupted trafficking of the shp PLP/DM20 within oligodendrocytes. Immunohistochemical studies revealed significantly reduced levels of PLP/DM20 and other major myelin components such as myelin basic protein (MBP), myelin associated glycoprotein (MAG), and 2',3'-cyclic nucleotide 3'-phosphodiesterase (CNP) in shp myelin. The distribution of shp PLP/DM20 proteins were altered and mostly retained in perinuclear cytoplasm and proximal processes, which co-localized with distended rough endoplasmic reticulum (RER) within oligodendrocytes. No abnormal accumulation of MAG, MBP, or CNP in the cell body was found. These results suggest that mutated PLP/DM20 in the shp could be selectively retained in RER, causing disruption of their translocation to the periphery to myelinate axons.
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Affiliation(s)
- Jonathan Song
- Department of Medical Sciences, School of Veterinary Medicine, University of Wisconsin, Madison, Wisconsin 53706, USA.
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Cortés MDC, Gavito B, Ita ML, Valencia J, Eguibar JR. Characterization of the spontaneous and gripping-induced immobility episodes ontaiep rats. Synapse 2005; 58:95-101. [PMID: 16088950 DOI: 10.1002/syn.20188] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
In 1989, we described a new autosomic-recessive myelin-mutant rat that develops a progressive motor syndrome characterized by tremor, ataxia, immobility episodes (IEs), epilepsy, and paralysis. taiep is the acronym of these symptoms. The rat developed a hypomyelination, followed by demyelination. At an age of 7-8 months, taiep rats developed IEs, characterized electroencephalographically by REM sleep-like cortical activity. In our study, we analyzed the ontogeny of gripping-induced IEs between 5 and 18 months, their dependence to light-dark changes, sexual dimorphism, and susceptibility to mild stress. Our results showed that IEs start at an age of 6.5 months, with a peak frequency between 8.5 and 9.5 months. IEs have two peaks, one in the morning (0800-1000 h) and a second peak in the middle of the night (2300-0100 h). Spontaneous IEs showed an even distribution with a mean of 3 IEs every 2 h. IEs are sexually dimorphic being more common in male rats. The IEs can be induced by gripping the rat by the tail or the thorax, but most of the IEs were produced by gripping the tail. Mild stress produced by i.p. injection of physiological saline significantly decreased IEs. These results suggested that IEs are dependent on several biological variables, which are caused by hypomyelination, followed by demyelization, which causes alterations in the brainstem and hypothalamic mechanisms responsible for the sleep-wake cycle regulation, producing emergence of REM sleep-like behavior during awake periods.
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Affiliation(s)
- Ma Del Carmen Cortés
- Instituto de Fisiología, Benemérita Universidad Autónoma de Puebla; Apdo. Postal 406. Puebla, Pue. C.P. 72000, Mexico
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Song J, Carson JH, Barbarese E, Li FY, Duncan ID. RNA transport in oligodendrocytes from the taiep mutant rat. Mol Cell Neurosci 2003; 24:926-38. [PMID: 14697659 DOI: 10.1016/s1044-7431(03)00254-9] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
The results presented here identify a new RNA trafficking phenotype in taiep oligodendrocytes that increases the frequency of reversals and restricts the extent of transport of RNA containing the A2RE transport signal from MBP mRNA. The taiep rat is a myelin mutant characterized by excessive accumulation of microtubules in oligodendrocytes and myelin deficiency in the central nervous system. The taiep RNA trafficking is developmentally correlated with the microtubule accumulation in oligodendrocytes and can be partially suppressed by reducing microtubule density with nocodazole or inhibiting dynein activity by coinjecting anti-dynein antibodies. These results suggest that RNA trafficking in taiep oligodendrocytes is inhibited by enhanced dynein activity that neutralizes or lessens the normal overriding power of the plus-end directed motor kinesin. Altered orientation of microtubules in oligodendrocyte fine processes and a physical barrier created by densely packed microtubules may also contribute to the inhibition of RNA trafficking in taiep oligodendrocytes.
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Affiliation(s)
- Jonathan Song
- Department of Medical Sciences, School of Veterinary Medicine, University of Wisconsin, Madison, WI 53706, USA.
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Uschkureit T, Spörkel O, Büssow H, Stoffel W. Rumpshaker-like proteolipid protein (PLP) ratio in a mouse model with unperturbed structural and functional integrity of the myelin sheath and axons in the central nervous system. Glia 2001; 35:63-71. [PMID: 11424193 DOI: 10.1002/glia.1071] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
The gene plp on the X chromosome encodes the isoforms proteolipid protein (PLP) and DM(20), two dominant integral membrane proteins of central nervous system (CNS) myelin. DM(20) results from the activation of the cryptic splice site in exon III of the PLP gene. We inserted a sense-orientated loxP flanked neomycin-gene into intron III of the plp sequence, using homologous recombination in embryonic stem cells and generated the homozygous neoS mouse line. Unlike the previously described complete PLP/DM(20) ablation (plp(-/-)), which has been obtained by introducing a neo-gene in antisense-orientation in the same position of intron III, the plp expression surprisingly revealed reduced mRNA levels. The PLP isoform was reduced to 50%, but DM(20) expression was unaffected. This protein pattern resembles the expression profile of the PLP isoforms in the natural occurring rumpshaker mutant. Electron microscopic examination revealed a normal compaction of CNS-myelin and maintenance of axon integrity. PLP expression levels of the wt control were recovered by Cre excision of the neo-selection gene after intercrossing neoS mice and oligodendrocyte-specific Cre-mice. These data strongly hint at different functions of intron III in PLP/DM(20)-specific splicing and mRNA stability. Furthermore evidence is provided for functionally affected translation products of the PLP gene in the rumpshaker mutant, whereas no PLP-isoform occur in plp(-/-) mice generated by introducing a selectable marker into intron III in antisense orientation.
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MESH Headings
- Alternative Splicing/genetics
- Animals
- Axons/metabolism
- Central Nervous System/abnormalities
- Central Nervous System/growth & development
- Central Nervous System/ultrastructure
- Disease Models, Animal
- Gene Expression Regulation, Developmental
- Gene Targeting/methods
- Introns/genetics
- Mice
- Mice, Knockout/abnormalities
- Mice, Knockout/genetics
- Mice, Knockout/growth & development
- Mice, Neurologic Mutants/abnormalities
- Mice, Neurologic Mutants/genetics
- Mice, Neurologic Mutants/growth & development
- Myelin Proteolipid Protein/genetics
- Myelin Proteolipid Protein/metabolism
- Myelin Sheath/metabolism
- Myelin Sheath/ultrastructure
- Neomycin
- Nerve Tissue Proteins
- Phenotype
- RNA, Messenger/genetics
- RNA, Messenger/metabolism
- Stem Cells/cytology
- Stem Cells/metabolism
- Transcription, Genetic/genetics
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Affiliation(s)
- T Uschkureit
- Laboratory for Molecular Neuroscience, University of Cologne, Cologne, Germany
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