β-HEXOSAMINIDASES IN THE NERVOUS SYSTEM: THE QUANTITATIVE HISTOCHEMISTRY OF β-GLUCOSAMINIDASE AND β-GALACTOSAMINIDASE IN THE CEREBELLAR CORTEX AND SUBJACENT WHITE MATTER

A modification of an existing fluorimetric method for the assay of β-glucosaminidase and β-galactosaminidase, based upon the hydrolysis of the corresponding 4-methylumbelliferyl glycosaminides, is described. The method is simple and convenient; its sensitivity is 3 x 10–8 M for the assay of β-glucosaminidase and 1 x 10–8 M for β-galactosaminidase. The results obtained on brain homogenates and dissected sections of cerebellar cortex and subjacent white matter of rat, rabbit and monkey were found to be similar to those obtained with the standard colorimetric procedures using p-nitrophenyl substrates. In each species, in each layer of cerebellar cortex and subjacent white matter, there were only minimal differences in the ratios of β-glucosaminidase to β-galactosaminidase activity, suggesting that a single enzyme possesses both activities. β-Glucosaminidase and β-galactosaminidase in the cerebellum were most active in the cellular granular layer, suggesting an association of β-hexosaminidase activity with neuronal cell bodies as has been found with other lysomal enzymes.

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The Red Neuronal Pigment in the Nervous System of the Mussel, Mytilus Edulis: Localization and Its Effect on Lateral Ciliary Activity with Spectral and Analytical Changes

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100098952 ◽

1981 ◽

Vol 39 ◽

pp. 494-495

Author(s):

Anthony A. Paparo ◽

Judith A. Murphy

Keyword(s):

Nervous System ◽

Mytilus Edulis ◽

Neuronal Cell ◽

Ciliary Activity ◽

Neuronal Cell Bodies ◽

The Central Nervous System ◽

Intracellular Organelles ◽

The Common ◽

The Individual ◽

Cryostat Sections

The purpose of this study was to localize the red neuronal pigment in Mytilus edulis and examine its role in the control of lateral ciliary activity in the gill. The visceral ganglia (Vg) in the central nervous system show an over al red pigmentation. Most red pigments examined in squash preps and cryostat sec tions were localized in the neuronal cell bodies and proximal axon regions. Unstained cryostat sections showed highly localized patches of this pigment scattered throughout the cells in the form of dense granular masses about 5-7 um in diameter, with the individual granules ranging from 0.6-1.3 um in diame ter. Tissue stained with Gomori's method for Fe showed bright blue granular masses of about the same size and structure as previously seen in unstained cryostat sections.Thick section microanalysis (Fig.l) confirmed both the localization and presence of Fe in the nerve cell. These nerve cells of the Vg share with other pigmented photosensitive cells the common cytostructural feature of localization of absorbing molecules in intracellular organelles where they are tightly ordered in fine substructures.

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Transplantation of Fetal CNS Tissue Into the Peripheral Nervous System: A Model to Study Aberrant Changes in the Neuronal Cytoskeleton

Journal of Neural Transplantation and Plasticity ◽

10.1155/np.1991.193 ◽

1991 ◽

Vol 2 (3-4) ◽

pp. 193-205 ◽

Cited By ~ 7

Author(s):

Laurie C. Doering

Keyword(s):

Nervous System ◽

Substantia Nigra ◽

Peripheral Nervous System ◽

Growth Factor Receptor ◽

Morphological Characteristics ◽

Neuronal Cell ◽

Cytoskeletal Proteins ◽

Adult Rats ◽

Neuronal Cell Bodies ◽

Immunocytochemical Techniques

Defined regions (septum, substantia nigra) of the embryonic central nervous system (CNS) were transplanted into the sciatic nerves of young adult rats. Immunocytochemical techniques were used to examine the expression of neurotransmitter related enzymes and neuronal cytoskeletal proteins in the grafts.The origin of the septal grafts was confirmed by immunoreactivity in nenrons to choline acetyltransferase and the β-nerve growth factor receptor (192-IgG). In substantia nigra grafts, neuronal perikarya and processes were identified with an antibody directed against tyrosine hydroxylase. Typical spatial distributions of phosphorylated (Mr200,000) and non phosphorylated (Mr168,000 & 200,000) neurofilaments were observed in the short term (1-2 months) grafts with the monoclonal antibodies RT97 and SMI-32 respectively. Dense dendrite arbors and neuronal cell bodies were immunostained with an antibody that recognizes a high molecular weight microtubule associated protein (MAP2).In the long term (1 year) transplants, prominent cytoskeletal changes in the somata, axons and dendrites of neurons were evident. The cells showed a shift in phosphorylated neurofilament staining from the axon to the soma accompanied by a reduction in axonal immunoreactivity in the adjacent neuropil, Other abnormal features included swollen perikarya, hypertrophied axonal segments and Short segments of kinked axons. Regression of the dendrite trees in the long standing grafts was also apparent when sections were reacted with the MAP2 antibody.These experiments indicate that grafted fetal neurons, isolated in the peripheral nervous system, differentiate and express markers like their counterpartsin situ. After extended time periods under these circumstances, cytoskeletal modifications become apparent in the neurons. These aberrant changes are similar to morphological characteristics associated with aging and neurodegenerative disorders. This experimental paradigm offers a new approach, to study cytoskeletal disturbances in neurons and provides a unique opportunity to examine conditions that may modulate the abnormal changes.

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Drosophila ßHeavy-Spectrin is required in polarized ensheathing glia that form a diffusion-barrier around the neuropil

Nature Communications ◽

10.1038/s41467-021-26462-x ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

Nicole Pogodalla ◽

Holger Kranenburg ◽

Simone Rey ◽

Silke Rodrigues ◽

Albert Cardona ◽

...

Keyword(s):

Nervous System ◽

Plasma Membrane ◽

Diffusion Barrier ◽

Neuronal Cell ◽

Apical Plasma Membrane ◽

Neuronal Cell Bodies ◽

The Central Nervous System ◽

Basolateral Plasma Membrane ◽

Nervous System Function ◽

Spectrin Cytoskeleton

AbstractIn the central nervous system (CNS), functional tasks are often allocated to distinct compartments. This is also evident in the Drosophila CNS where synapses and dendrites are clustered in distinct neuropil regions. The neuropil is separated from neuronal cell bodies by ensheathing glia, which as we show using dye injection experiments, contribute to the formation of an internal diffusion barrier. We find that ensheathing glia are polarized with a basolateral plasma membrane rich in phosphatidylinositol-(3,4,5)-triphosphate (PIP3) and the Na+/K+-ATPase Nervana2 (Nrv2) that abuts an extracellular matrix formed at neuropil-cortex interface. The apical plasma membrane is facing the neuropil and is rich in phosphatidylinositol-(4,5)-bisphosphate (PIP2) that is supported by a sub-membranous ßHeavy-Spectrin cytoskeleton. ßHeavy-spectrin mutant larvae affect ensheathing glial cell polarity with delocalized PIP2 and Nrv2 and exhibit an abnormal locomotion which is similarly shown by ensheathing glia ablated larvae. Thus, polarized glia compartmentalizes the brain and is essential for proper nervous system function.

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faint sausage encodes a novel extracellular protein of the immunoglobulin superfamily required for cell migration and the establishment of normal axonal pathways in the Drosophila nervous system

Development ◽

10.1242/dev.125.14.2747 ◽

1998 ◽

Vol 125 (14) ◽

pp. 2747-2758 ◽

Cited By ~ 2

Author(s):

A.C. Lekven ◽

U. Tepass ◽

M. Keshmeshian ◽

V. Hartenstein

Keyword(s):

Nervous System ◽

Cell Migration ◽

Peripheral Nervous System ◽

Neuronal Cell ◽

Protein Product ◽

Extracellular Protein ◽

Immunoglobulin Superfamily ◽

Neuronal Cell Bodies ◽

The Central Nervous System ◽

High Concentrations

We examined the structure of the nervous system in Drosophila embryos homozygous for a null mutation in the faint sausage (fas) gene. In the peripheral nervous system (PNS) of fas mutants, neurons fail to delaminate from the ectodermal epithelium; in the central nervous system (CNS), the positions of neuronal cell bodies and glial cells are abnormal and normal axonal pathways do not form. Sequence analysis of fas cDNAs revealed that the fas protein product has characteristics of an extracellular protein and that it is a novel member of the immunoglobulin (Ig) superfamily. In situ hybridization demonstrated that fas transcripts are expressed throughout the embryo but they are in relatively high concentrations in the lateral ectoderm, from which the peripheral nervous system delaminates and in the CNS. Antiserum directed against Fas protein was found to stain neurons but not glia in the CNS. We conclude that fas encodes a protein that, in the developing nervous system, is present on the surface of neurons and is essential for nerve cell migration and the establishment of axonal pathways.

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CYTOCHEMICAL LOCALIZATION OF BRAIN NICOTINAMIDE ADENINE DINUCLEOTIDE PHOSPHATE (OXIDIZED)-DEPENDENT DEHYDROGENASES QUALITATIVE AND QUANTITATIVE DISTRIBUTIONS

Journal of Histochemistry & Cytochemistry ◽

10.1177/22.1.7 ◽

1974 ◽

Vol 22 (1) ◽

pp. 7-19 ◽

Cited By ~ 38

Author(s):

K. L. SIMS ◽

F. C. KAUFFMAN ◽

E. C. JOHNSON ◽

V. M. PICKEL

Keyword(s):

Nervous System ◽

Nicotinamide Adenine Dinucleotide ◽

Molecular Layer ◽

Nicotinamide Adenine Dinucleotide Phosphate ◽

Neuronal Cell ◽

Nicotinamide Adenine ◽

Experimental Conditions ◽

Cytochemical Localization ◽

Neuronal Cell Bodies ◽

Neuronal Processes

This study compares the histochemical and microchemical localizations of nicotinamide adenine dinucleotide phosphate (reduced) and nicotinamide adenine dinucleotide (reduced) diaphorases and four nicotinamide adenine dinucleotide phosphate (oxidized)-dependent enzymes (glucose 6-phosphate, 6-phosphogluconate, malate and isocitrate dehydrogenases) in areas of rat metencephalon and spinal cord. For the four nicotinamide adenine dinucleotide phosphate (NADP) enzymes, the pattern of localization following use of a modified tetrazolium procedure was compared with quantitative data obtained by microdissection from the same areas in adjacent sections. Optimal experimental conditions for reaction pH, temperature, substrate, cofactor and divalent cation concentrations were used for both the quantitative analysis following microdissection and the histochemical tetrazolium procedure. Consecutive sections were also examined for isocitrate dehydrogenase (nicotinamide adenine dinucleotide (oxidized)) and nicotinamide adenine dinucleotide (reduced) diaphorase activities in addition to seriatim thionine reference sections. Our results indicate that, within the central nervous system, certain characteristic qualitative differences exist in the distribution of the nicotinamide adenine dinucleotide phosphate (oxidized)- and nicotinamide adenine dinucleotide (oxidized)-dependent dehydrogenase enzymes. Nicotinamide adenine, dinucleotide enzymes are visualized predominantly in neuronal cell bodies or neuropil consisting primarily of neuronal processes; in adjacent sections, NADP enzyme activities are visualized almost exclusively in glial elements with two important exceptions. The first is the cerebellar molecular layer where the results from both micro- and histochemical techniques indicate high levels of the NADP enzymes relative to other dehydrogenases and high activity relative to the levels of these NADP enzymes in other nervous system areas. The second exception occurs in those neuronal groups known to contain high levels of catecholamines; these data are the subject of a companion report.

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Diversity of developing peripheral glia revealed by single cell RNA sequencing

10.1101/2020.12.04.411975 ◽

2020 ◽

Author(s):

OE Tasdemir-Yilmaz ◽

NR Druckenbrod ◽

OO Olukoya ◽

AR Yung ◽

I Bastille ◽

...

Keyword(s):

Nervous System ◽

Single Cell ◽

Rna Sequencing ◽

Neuronal Cell ◽

Neuronal Diversity ◽

Sensory Stimuli ◽

Neuronal Cell Bodies ◽

Single Cell Rna Sequencing ◽

Comprehensive Survey ◽

Peripheral Glia

AbstractThe peripheral nervous system responds to a wide variety of sensory stimuli, a process that requires great neuronal diversity. These diverse peripheral sensory neurons are closely associated with glial cells that originate from the neural crest (NC). However, the molecular nature and origins of diversity among peripheral glia is not understood. Here we used single cell RNA sequencing to profile and compare developing and mature glia from somatosensory lumbar dorsal root ganglia (DRG) and auditory spiral ganglia (SG). We found that the glial precursors (GPs) differ in their transcriptional profile and prevalence in these two systems. Despite their unique features, somatosensory and auditory GPs undergo convergent differentiation to generate myelinating and non-myelinating Schwann cells that are molecularly uniform. By contrast, although satellite glia surround the neuronal cell bodies in both ganglia, we found that those in the SG express multiple myelination-associated genes, while DRG satellite cells express components that suppress myelination. Lastly, we identified a set of glial signature genes that are also expressed by placode-derived supporting cells, providing new insights into commonalities among glia across the nervous system. This comprehensive survey of gene expression in peripheral glia constitutes a valuable resource for understanding how glia acquire specialized functions and how their roles differ across sensory modalities.

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New oligodendrocytes exhibit more abundant and accurate myelin regeneration than those that survive demyelination

10.1101/2020.05.22.110551 ◽

2020 ◽

Cited By ~ 4

Author(s):

Sarah A Neely ◽

Jill M Williamson ◽

Anna Klingseisen ◽

Lida Zoupi ◽

Jason J Early ◽

...

Keyword(s):

Multiple Sclerosis ◽

Central Nervous System ◽

Nervous System ◽

Neuronal Cell ◽

Live Imaging ◽

Therapeutic Strategies ◽

Demyelinating Diseases ◽

Neuronal Cell Bodies ◽

The Central Nervous System

Regeneration of myelin (remyelination) in the central nervous system (CNS) has long been thought to be principally mediated by newly generated oligodendrocytes, a premise underpinning therapeutic strategies for demyelinating diseases, including multiple sclerosis (MS). Recent studies have indicated that oligodendrocytes that survive demyelination can also contribute to remyelination, including in MS, but it is unclear how remyelination by surviving oligodendrocytes compares to that of newly generated oligodendrocytes. Here we studied oligodendrocytes in MS, and also imaged remyelination in vivo by surviving and new oligodendrocytes using zebrafish. We define a previously unappreciated pathology in MS, myelination of neuronal cell bodies, which is recapitulated during remyelination by surviving oligodendrocytes in zebrafish. Live imaging also revealed that surviving oligodendrocytes make very few new sheaths, but can support sheath growth along axons. In comparison, newly made oligodendrocytes make abundant new sheaths, properly targeted to axons, and exhibit a much greater capacity for regeneration.

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Morpho-Functional Consequences of Swiss Cheese Knockdown in Glia of Drosophila melanogaster

Cells ◽

10.3390/cells10030529 ◽

2021 ◽

Vol 10 (3) ◽

pp. 529

Author(s):

Elena V. Ryabova ◽

Pavel A. Melentev ◽

Artem E. Komissarov ◽

Nina V. Surina ◽

Ekaterina A. Ivanova ◽

...

Keyword(s):

Central Nervous System ◽

Nervous System ◽

Drosophila Melanogaster ◽

Peripheral Nervous System ◽

Neuronal Cell ◽

Cortical Region ◽

Swiss Cheese ◽

Neuronal Cell Bodies ◽

Functional Consequences ◽

The Central Nervous System

Glia are crucial for the normal development and functioning of the nervous system in many animals. Insects are widely used for studies of glia genetics and physiology. Drosophila melanogaster surface glia (perineurial and subperineurial) form a blood–brain barrier in the central nervous system and blood–nerve barrier in the peripheral nervous system. Under the subperineurial glia layer, in the cortical region of the central nervous system, cortex glia encapsulate neuronal cell bodies, whilst in the peripheral nervous system, wrapping glia ensheath axons of peripheral nerves. Here, we show that the expression of the evolutionarily conserved swiss cheese gene is important in several types of glia. swiss cheese knockdown in subperineurial glia leads to morphological abnormalities of these cells. We found that the number of subperineurial glia nuclei is reduced under swiss cheese knockdown, possibly due to apoptosis. In addition, the downregulation of swiss cheese in wrapping glia causes a loss of its integrity. We reveal transcriptome changes under swiss cheese knockdown in subperineurial glia and in cortex + wrapping glia and show that the downregulation of swiss cheese in these types of glia provokes reactive oxygen species acceleration. These results are accompanied by a decline in animal mobility measured by the negative geotaxis performance assay.

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IMP-L2: an essential secreted immunoglobulin family member implicated in neural and ectodermal development in Drosophila

Development ◽

10.1242/dev.119.4.1237 ◽

1993 ◽

Vol 119 (4) ◽

pp. 1237-1250 ◽

Cited By ~ 1

Author(s):

J.C. Garbe ◽

E. Yang ◽

J.W. Fristrom

Keyword(s):

Nervous System ◽

Normal Development ◽

Neuronal Cell ◽

Subsequent Development ◽

Immunoglobulin Superfamily ◽

Gene Encoding ◽

Neuronal Cell Bodies ◽

Whole Mount ◽

Membrane Bound ◽

Blastoderm Stage

The Drosophila IMP-L2 gene was identified as a 20-hydroxyecdysone-induced gene encoding a membrane-bound polysomal transcript. IMP-L2 is an apparent secreted member of the immunoglobulin superfamily. We have used deficiencies that remove the IMP-L2 gene to demonstrate that IMP-L2 is essential in Drosophila. The viability of IMP-L2 null zygotes is influenced by maternal IMP-L2. IMP-L2 null progeny from IMP-L2+ mothers exhibit a semilethal phenotype. IMP-L2 null progeny from IMP-L2 null mothers are 100% lethal. An IMP-L2 transgene completely suppresses the zygotic lethal phenotype and partially suppresses the lethality of IMP-L2 null progeny from IMP-L2 null mothers. In embryos, IMP-L2 mRNA is first expressed at the cellular blastoderm stage and continues to be expressed through subsequent development. IMP-L2 mRNA is detected in several sites including the ventral neuroectoderm, the tracheal pits, the pharynx and esophagus, and specific neuronal cell bodies. Staining of whole-mount embryos with anti-IMP-L2 antibodies shows that IMP-L2 protein is localized to specific neuronal structures late in embryogenesis. Expression of IMP-L2 protein in neuronal cells suggests a role in the normal development of the nervous system but no severe morphological abnormalities have been detected in IMP-L2 null embryos.

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Drosophila beta-Heavy-Spectrin is required in polarized ensheathing glia that form a diffusion-barrier around the neuropil

10.1101/2021.07.21.453164 ◽

2021 ◽

Author(s):

Nicole Pogodalla ◽

Holger Kranenburg ◽

Simone Rey ◽

Silke Rodrigues ◽

Albert Cardona ◽

...

Keyword(s):

Nervous System ◽

Plasma Membrane ◽

Diffusion Barrier ◽

Neuronal Cell ◽

Apical Plasma Membrane ◽

Neuronal Cell Bodies ◽

Insect Cns ◽

The Central Nervous System ◽

Nervous System Function ◽

Spectrin Cytoskeleton

In the central nervous system (CNS), functional tasks are often allocated to distinct compartments. This is also evident in the insect CNS where synapses and dendrites are clustered in distinct neuropil regions. The neuropil is separated from neuronal cell bodies by ensheathing glia, which as we show using dye injection experiments forms an internal diffusion barrier. We find that ensheathing glial cells are polarized with a basolateral plasma membrane rich in phosphatidylinositol-(3,4,5)-triphosphate (PIP3) and the Na+/K+-ATPase Nervana2 (Nrv2) that abuts an extracellular matrix formed at neuropil-cortex interface. The apical plasma membrane is facing the neuropil and is rich in phosphatidylinositol-(4,5)-bisphosphate (PIP2) that is supported by a sub-membranous beta-Heavy-Spectrin cytoskeleton. beta-Heavy-spectrin mutant larvae affect ensheathing glial cell polarity with delocalized PIP2 and Nrv2 and exhibit an abnormal locomotion which is similarly shown by ensheathing glia ablated larvae. Thus, polarized glia compartmentalizes the brain and is essential for proper nervous system function.

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