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González YR, Kamkar F, Jafar-Nejad P, Wang S, Qu D, Alvarez LS, Hawari D, Sonnenfeld M, Slack RS, Albert PR, Park DS, Joselin A. PFTK1 kinase regulates axogenesis during development via RhoA activation. BMC Biol 2023; 21:240. [PMID: 37907898 PMCID: PMC10617079 DOI: 10.1186/s12915-023-01732-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2022] [Accepted: 10/11/2023] [Indexed: 11/02/2023] Open
Abstract
BACKGROUND PFTK1/Eip63E is a member of the cyclin-dependent kinases (CDKs) family and plays an important role in normal cell cycle progression. Eip63E expresses primarily in postnatal and adult nervous system in Drosophila melanogaster but its role in CNS development remains unknown. We sought to understand the function of Eip63E in the CNS by studying the fly ventral nerve cord during development. RESULTS Our results demonstrate that Eip63E regulates axogenesis in neurons and its deficiency leads to neuronal defects. Functional interaction studies performed using the same system identify an interaction between Eip63E and the small GTPase Rho1. Furthermore, deficiency of Eip63E homolog in mice, PFTK1, in a newly generated PFTK1 knockout mice results in increased axonal outgrowth confirming that the developmental defects observed in the fly model are due to defects in axogenesis. Importantly, RhoA phosphorylation and activity are affected by PFTK1 in primary neuronal cultures. We report that GDP-bound inactive RhoA is a substrate of PFTK1 and PFTK1 phosphorylation is required for RhoA activity. CONCLUSIONS In conclusion, our work establishes an unreported neuronal role of PFTK1 in axon development mediated by phosphorylation and activation of GDP-bound RhoA. The results presented add to our understanding of the role of Cdks in the maintenance of RhoA-mediated axon growth and its impact on CNS development and axonal regeneration.
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Affiliation(s)
| | - Fatemeh Kamkar
- Department of Cellular and Molecular Medicine, University of Ottawa, Ottawa, ON, K1H 8M5, Canada
| | - Paymaan Jafar-Nejad
- Department of Cellular and Molecular Medicine, University of Ottawa, Ottawa, ON, K1H 8M5, Canada
- Present Address: Ionis Pharmaceuticals Inc., Carlsbad, CA, 92010, USA
| | - Suzi Wang
- Department of Cellular and Molecular Medicine, University of Ottawa, Ottawa, ON, K1H 8M5, Canada
| | - Dianbo Qu
- Department of Cellular and Molecular Medicine, University of Ottawa, Ottawa, ON, K1H 8M5, Canada
| | - Leticia Sanchez Alvarez
- Department of Cellular and Molecular Medicine, University of Ottawa, Ottawa, ON, K1H 8M5, Canada
| | - Dina Hawari
- Department of Cellular and Molecular Medicine, University of Ottawa, Ottawa, ON, K1H 8M5, Canada
| | - Margaret Sonnenfeld
- Department of Cellular and Molecular Medicine, University of Ottawa, Ottawa, ON, K1H 8M5, Canada
| | - Ruth S Slack
- Department of Cellular and Molecular Medicine, University of Ottawa, Ottawa, ON, K1H 8M5, Canada
| | - Paul R Albert
- Ottawa Hospital Research Institute and Brain and Mind Research Institute, University of Ottawa, Ottawa, ON, K1H 8M5, Canada
| | - David S Park
- Department of Clinical Neurosciences, Hotchkiss Brain Institute, University of Calgary, Calgary, AB, T2N 4N1, Canada.
| | - Alvin Joselin
- Department of Clinical Neurosciences, Hotchkiss Brain Institute, University of Calgary, Calgary, AB, T2N 4N1, Canada.
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Ghosh A, Kling T, Snaidero N, Sampaio JL, Shevchenko A, Gras H, Geurten B, Göpfert MC, Schulz JB, Voigt A, Simons M. A global in vivo Drosophila RNAi screen identifies a key role of ceramide phosphoethanolamine for glial ensheathment of axons. PLoS Genet 2013; 9:e1003980. [PMID: 24348263 PMCID: PMC3861124 DOI: 10.1371/journal.pgen.1003980] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2013] [Accepted: 10/12/2013] [Indexed: 01/08/2023] Open
Abstract
Glia are of vital importance for all complex nervous system. One of the many functions of glia is to insulate and provide trophic and metabolic support to axons. Here, using glial-specific RNAi knockdown in Drosophila, we silenced 6930 conserved genes in adult flies to identify essential genes and pathways. Among our screening hits, metabolic processes were highly represented, and genes involved in carbohydrate and lipid metabolic pathways appeared to be essential in glia. One critical pathway identified was de novo ceramide synthesis. Glial knockdown of lace, a subunit of the serine palmitoyltransferase associated with hereditary sensory and autonomic neuropathies in humans, resulted in ensheathment defects of peripheral nerves in Drosophila. A genetic dissection study combined with shotgun high-resolution mass spectrometry of lipids showed that levels of ceramide phosphoethanolamine are crucial for axonal ensheathment by glia. A detailed morphological and functional analysis demonstrated that the depletion of ceramide phosphoethanolamine resulted in axonal defasciculation, slowed spike propagation, and failure of wrapping glia to enwrap peripheral axons. Supplementing sphingosine into the diet rescued the neuropathy in flies. Thus, our RNAi study in Drosophila identifies a key role of ceramide phosphoethanolamine in wrapping of axons by glia.
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Affiliation(s)
- Aniket Ghosh
- Max Planck Institute for Experimental Medicine, Göttingen, Germany
- Department of Neurology, University of Göttingen, Göttingen, Germany
| | - Tina Kling
- Max Planck Institute for Experimental Medicine, Göttingen, Germany
- Department of Neurology, University of Göttingen, Göttingen, Germany
| | - Nicolas Snaidero
- Max Planck Institute for Experimental Medicine, Göttingen, Germany
- Department of Neurology, University of Göttingen, Göttingen, Germany
| | - Julio L. Sampaio
- Max Planck Institute of Molecular Cell Biology and Genetics, Dresden, Germany
| | - Andrej Shevchenko
- Max Planck Institute of Molecular Cell Biology and Genetics, Dresden, Germany
| | - Heribert Gras
- Department of Cellular Neurobiology, University of Göttingen, Göttingen, Germany
| | - Bart Geurten
- Department of Cellular Neurobiology, University of Göttingen, Göttingen, Germany
| | - Martin C. Göpfert
- Department of Cellular Neurobiology, University of Göttingen, Göttingen, Germany
| | - Jörg B. Schulz
- Department of Neurology, University Medical Center, RWTH Aachen, Aachen, Germany
| | - Aaron Voigt
- Department of Neurology, University Medical Center, RWTH Aachen, Aachen, Germany
| | - Mikael Simons
- Max Planck Institute for Experimental Medicine, Göttingen, Germany
- Department of Neurology, University of Göttingen, Göttingen, Germany
- * E-mail:
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3
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Enriched pathways for major depressive disorder identified from a genome-wide association study. Int J Neuropsychopharmacol 2012; 15:1401-11. [PMID: 22243633 DOI: 10.1017/s1461145711001891] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
Major depressive disorder (MDD) has caused a substantial burden of disease worldwide with moderate heritability. Despite efforts through conducting numerous association studies and now, genome-wide association (GWA) studies, the success of identifying susceptibility loci for MDD has been limited, which is partially attributed to the complex nature of depression pathogenesis. A pathway-based analytic strategy to investigate the joint effects of various genes within specific biological pathways has emerged as a powerful tool for complex traits. The present study aimed to identify enriched pathways for depression using a GWA dataset for MDD. For each gene, we estimated its gene-wise p value using combined and minimum p value, separately. Canonical pathways from the Kyoto Encyclopedia of Genes and Genomes (KEGG) and BioCarta were used. We employed four pathway-based analytic approaches (gene set enrichment analysis, hypergeometric test, sum-square statistic, sum-statistic). We adjusted for multiple testing using Benjamini & Hochberg's method to report significant pathways. We found 17 significantly enriched pathways for depression, which presented low-to-intermediate crosstalk. The top four pathways were long-term depression (p⩽1×10-5), calcium signalling (p⩽6×10-5), arrhythmogenic right ventricular cardiomyopathy (p⩽1.6×10-4) and cell adhesion molecules (p⩽2.2×10-4). In conclusion, our comprehensive pathway analyses identified promising pathways for depression that are related to neurotransmitter and neuronal systems, immune system and inflammatory response, which may be involved in the pathophysiological mechanisms underlying depression. We demonstrated that pathway enrichment analysis is promising to facilitate our understanding of complex traits through a deeper interpretation of GWA data. Application of this comprehensive analytic strategy in upcoming GWA data for depression could validate the findings reported in this study.
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4
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The fundamental role of subcellular topography in peripheral nerve repair therapies. Biomaterials 2012; 33:4264-76. [DOI: 10.1016/j.biomaterials.2012.02.043] [Citation(s) in RCA: 92] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2012] [Accepted: 02/24/2012] [Indexed: 12/17/2022]
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6
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Hartenstein V. Morphological diversity and development of glia in Drosophila. Glia 2011; 59:1237-52. [PMID: 21438012 DOI: 10.1002/glia.21162] [Citation(s) in RCA: 93] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2010] [Accepted: 01/25/2011] [Indexed: 12/31/2022]
Abstract
Insect glia represents a conspicuous and diverse population of cells and plays a role in controlling neuronal progenitor proliferation, axonal growth, neuronal differentiation and maintenance, and neuronal function. Genetic studies in Drosophila have elucidated many aspects of glial structure, function, and development. Just as in vertebrates, it appears as if different classes of glial cells are specialized for different functions. On the basis of topology and cell shape, glial cells of the central nervous system fall into three classes (Fig. 1A-C): (i) surface glia that extend sheath-like processes to wrap around the entire brain; (ii) cortex glia (also called cell body-associated glia) that encapsulate neuronal somata and neuroblasts which form the outer layer (cortex) of the central nervous system; (iii) neuropile glia that are located at the interface between the cortex and the neuropile, the central domain of the nervous system formed by the highly branched neuronal processes and their synaptic contacts. Surface glia is further subdivided into an outer, perineurial layer, and an inner, subperineurial layer. Likewise, neuropile glia comprises a class of cells that remain at the surface of the neuropile (ensheathing glia), and a second class that forms profuse lamellar processes around nerve fibers within the neuropile (astrocyte-like or reticular glia). Glia also surrounds the peripheral nerves and sensory organs; here, one also recognizes perineurial and subperineurial glia, and a third type called "wrapping glia" that most likely corresponds to the ensheathing glia of the central nervous system. Much more experimental work is needed to determine how fundamental these differences between classes of glial cells are, or how and when during development they are specified. To aid in this work the following review will briefly summarize our knowledge of the classes of glial cells encountered in the Drosophila nervous system, and then survey their development from the embryo to adult.
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Affiliation(s)
- Volker Hartenstein
- Department of Molecular Cell and Developmental Biology, University of California Los Angeles, Los Angeles, California 90095, USA.
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7
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von Hilchen CM, Hein I, Technau GM, Altenhein B. Netrins guide migration of distinct glial cells in the Drosophila embryo. Development 2010; 137:1251-62. [DOI: 10.1242/dev.042853] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Development of the nervous system and establishment of complex neuronal networks require the concerted activity of different signalling events and guidance cues, which include Netrins and their receptors. In Drosophila, two Netrins are expressed during embryogenesis by cells of the ventral midline and serve as attractant or repellent cues for navigating axons. We asked whether glial cells, which are also motile, are guided by similar cues to axons, and analysed the influence of Netrins and their receptors on glial cell migration during embryonic development. We show that in Netrin mutants, two distinct populations of glial cells are affected: longitudinal glia (LG) fail to migrate medially in the early stages of neurogenesis, whereas distinct embryonic peripheral glia (ePG) do not properly migrate laterally into the periphery. We further show that early Netrin-dependent guidance of LG requires expression of the receptor Frazzled (Fra) already in the precursor cell. At these early stages, Netrins are not yet expressed by cells of the ventral midline and we provide evidence for a novel Netrin source within the neurogenic region that includes neuroblasts. Later in development, most ePG transiently express uncoordinated 5 (unc5) during their migratory phase. In unc5 mutants, however, two of these cells in particular exhibit defective migration and stall in, or close to, the central nervous system. Both phenotypes are reversible in cell-specific rescue experiments, indicating that Netrin-mediated signalling via Fra (in LG) or Unc5 (in ePG) is a cell-autonomous effect.
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Affiliation(s)
| | - Irina Hein
- Institute of Genetics, University of Mainz, Saarstrasse 21, D-55122 Mainz, Germany
| | - Gerhard M. Technau
- Institute of Genetics, University of Mainz, Saarstrasse 21, D-55122 Mainz, Germany
| | - Benjamin Altenhein
- Institute of Genetics, University of Mainz, Saarstrasse 21, D-55122 Mainz, Germany
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8
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Gibson NJ, Tolbert LP, Oland LA. Roles of specific membrane lipid domains in EGF receptor activation and cell adhesion molecule stabilization in a developing olfactory system. PLoS One 2009; 4:e7222. [PMID: 19787046 PMCID: PMC2746287 DOI: 10.1371/journal.pone.0007222] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2009] [Accepted: 09/06/2009] [Indexed: 11/18/2022] Open
Abstract
Background Reciprocal interactions between glial cells and olfactory receptor neurons (ORNs) cause ORN axons entering the brain to sort, to fasciculate into bundles destined for specific glomeruli, and to form stable protoglomeruli in the developing olfactory system of an experimentally advantageous animal species, the moth Manduca sexta. Epidermal growth factor receptors (EGFRs) and the cell adhesion molecules (IgCAMs) neuroglian and fasciclin II are known to be important players in these processes. Methodology/Principal Findings We report in situ and cell-culture studies that suggest a role for glycosphingolipid-rich membrane subdomains in neuron-glia interactions. Disruption of these subdomains by the use of methyl-β-cyclodextrin results in loss of EGFR activation, depletion of fasciclin II in ORN axons, and loss of neuroglian stabilization in the membrane. At the cellular level, disruption leads to aberrant ORN axon trajectories, small antennal lobes, abnormal arrays of olfactory glomerul, and loss of normal glial cell migration. Conclusions/Significance We propose that glycosphingolipid-rich membrane subdomains (possible membrane rafts or platforms) are essential for IgCAM-mediated EGFR activation and for anchoring of neuroglian to the cytoskeleton, both required for normal extension and sorting of ORN axons.
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Affiliation(s)
- Nicholas J Gibson
- Arizona Research Laboratories Division of Neurobiology, University of Arizona, Tucson, Arizona, United States of America.
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9
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PTEN attenuates PIP3/Akt signaling in the cochlea of the aging CBA/J mouse. Hear Res 2009; 264:86-92. [PMID: 19761823 DOI: 10.1016/j.heares.2009.09.002] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/12/2009] [Revised: 09/09/2009] [Accepted: 09/10/2009] [Indexed: 11/22/2022]
Abstract
We have previously reported the activation of cell death pathways in the sensory cells of the aging cochlea. Here we investigate age-associated changes in survival mechanisms focusing on phosphatidylinositol 3,4,5-trisphosphate (PIP(3))/Akt signaling. The animal model is the CBA/J mouse of 18 months of age prior to the onset of major functional loss (ABR thresholds, 26+/-8 dB SPL) which is compared to young animals of 3 months of age (ABR thresholds, 19+/-7 dB SPL). Immunostaining on cochlear cryosections revealed a wide-spread distribution of PIP(3) in the cochlea which was markedly attenuated in old animals in inner and outer hair cells, Deiters cells and pillar cells. Protein levels of the lipid phosphatase PTEN which regulates PIP(3) increased in those cells with aging while its mRNA did not, suggesting an age-related reduction of PTEN degradation. Furthermore, staining intensity of phosphorylated PTEN (ser380) and its nuclear localization increased. Consistent with a reduction of PIP(3), the phosphorylation of the downstream target Akt at threonine 308 significantly decreased in outer hair cells. The results suggest a decline of the survival capacity of aging outer hair cells due to a decrease in PIP(3)/Akt signaling caused by an increase of PTEN.
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Gocht D, Wagner S, Heinrich R. Recognition, presence, and survival of locust central nervous glia in situ and in vitro. Microsc Res Tech 2009; 72:385-97. [PMID: 19115332 DOI: 10.1002/jemt.20683] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Insect glial cells serve functions for the formation, maintenance, and performance of the central nervous system in ways similar to their vertebrate counterparts. Characterization of physiological mechanisms that underlie the roles of glia in invertebrates is largely incomplete, partly due to the lack of markers that universally label all types of glia throughout all developmental stages in various species. Studies on primary cell cultures from brains of Locusta migratoria demonstrated that the absence of anti-HRP immunoreactivity, which has previously been used to identify glial cells in undissociated brains, can also serve as a reliable glial marker in vitro, but only in combination with a viability test. As cytoplasmic membranes of cultured cells are prone to degradation when they lose viability, only cells that are both anti-HRP immunonegative and viable should be regarded as glial cells, whereas the lack of anti-HRP immunoreactivity alone is not sufficient. Cell viability can be assessed by the pattern of nuclear staining with DAPI (4',6-diamidino-2-phenylindole), a convenient, sensitive labeling method that can be used in combination with other immunocytochemical cellular markers. We determined the glia-to-neuron ratio in central brains of fourth nymphal stage of Locusta migratoria to be 1:2 both in situ and in dissociated primary cell cultures. Analysis of primary cell cultures revealed a progressive reduction of glial cells and indicated that dead cells detach from the substrate and vanish from the analysis. Such changes in the composition of cell cultures should be considered in future physiological studies on cell cultures from insect nervous systems.
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Affiliation(s)
- Daniela Gocht
- Department of Neurobiology, Institute for Zoology, University of Göttingen, Berliner Strasse 28, Göttingen, Germany
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11
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Seid MA, Wehner R. Delayed axonal pruning in the ant brain: A study of developmental trajectories. Dev Neurobiol 2009; 69:350-64. [DOI: 10.1002/dneu.20709] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
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Abstract
The ensheathment of neurons and their axons creates an ion-sensitive microenvironment that allows rapid conduction of nerve impulses. One of the fundamental questions about axonal ensheathment is how insulating glial cells wrap around axons. The mechanisms that underlie insulation of axons in invertebrates and vertebrates are not fully understood. In the present article we address cellular aspects of axonal ensheathment in Drosophila by taking advantage of glial mutants that illustrate a range of phenotypic defects including ensheathment of axons. From the findings of these mutant studies, we summarize that loss of glial cells, defects in glial membrane wrapping, failure of glial migration, and loss of specialized ladderlike septate junctions between ensheathing glial membranes result in axon-glial functional defects. These studies provide a broad perspective on glial ensheathment of axons in Drosophila and key insights into the anatomical and cellular aspects of axonal insulation. Given the powerful genetic approaches available in Drosophila, the axonal ensheathment process can be dissected in great detail to reveal the fundamental principles of ensheathment. These observations will be relevant to understanding the very similar processes in vertebrates, where defects in glial cell functions lead to devastating neurological diseases.
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Affiliation(s)
- Swati Banerjee
- Department of Cell and Molecular Physiology, Neurodevelopmental Disorders Research Center, University of North Carolina School of Medicine, Chapel Hill, North Carolina 27599-7545, USA
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von Hilchen CM, Beckervordersandforth RM, Rickert C, Technau GM, Altenhein B. Identity, origin, and migration of peripheral glial cells in the Drosophila embryo. Mech Dev 2007; 125:337-52. [PMID: 18077143 DOI: 10.1016/j.mod.2007.10.010] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2007] [Revised: 10/19/2007] [Accepted: 10/24/2007] [Indexed: 10/22/2022]
Abstract
Glial cells are crucial for the proper development and function of the nervous system. In the Drosophila embryo, the glial cells of the peripheral nervous system are generated both by central neuroblasts and sensory organ precursors. Most peripheral glial cells need to migrate along axonal projections of motor and sensory neurons to reach their final positions in the periphery. Here we studied the spatial and temporal pattern, the identity, the migration, and the origin of all peripheral glial cells in the truncal segments of wildtype embryos. The establishment of individual identities among these cells is reflected by the expression of a combinatorial code of molecular markers. This allows the identification of individual cells in various genetic backgrounds. Furthermore, mutant analysis of two of these marker genes, spalt major and castor, reveal their implication in peripheral glial development. Using confocal 4D microscopy to monitor and follow peripheral glia migration in living embryos, we show that the positioning of most of these cells is predetermined with minor variations, and that the order in which cells migrate into the periphery is almost fixed. By studying their lineages, we uncovered the origin of each of the peripheral glial cells and linked them to identified central and peripheral neural stem cells.
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Loesel R, Weigel S, Bräunig P. A simple fluorescent double staining method for distinguishing neuronal from non-neuronal cells in the insect central nervous system. J Neurosci Methods 2006; 155:202-6. [PMID: 16481042 DOI: 10.1016/j.jneumeth.2006.01.006] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2005] [Revised: 01/04/2006] [Accepted: 01/08/2006] [Indexed: 01/15/2023]
Abstract
Being able to discriminate between neurons and non-neuronal cells such as glia and tracheal cells has been a major problem in insect neuroscience, because glia-specific antisera are available for only a small number of species such as Drosophila melanogaster and Manduca sexta. Especially developmental or comparative studies often require an estimate of neuron numbers. Since neuronal and glial cell bodies are in many cases indiscernible in situ, a method to distinguish neurons from non-neuronal cells that works in any given species is wanting. Another application is cell culturing. Cultured cells usually change their outward shape dramatically after being isolated so that it is frequently impossible to tell neurons and glia apart. Here, we present a simple method that uses a commercially available antiserum directed against horseradish peroxidase, which specifically stains neurons but no other cell type in every insect species investigated. Counterstaining with DAPI, a fluorescent chromophore that binds to double-stranded DNA in the nuclei of all cells, yields the total number of cells in a given sample. Thus, double labeled cells can be identified as neurons, cells that carry only DAPI staining are non-neuronal.
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Affiliation(s)
- Rudi Loesel
- Institute of Biology II (Zoology), Unit of Developmental Biology and Morphology of Animals, Kopernikusstrasse 16, RWTH Aachen University, D-52074 Aachen, Germany.
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Abstract
Glial cells have diverse functions that are necessary for the proper development and function of complex nervous systems. Various insects, primarily the fruit fly Drosophila melanogaster and the moth Manduca sexta, have provided useful models of glial function during development. The present review will outline evidence of glial contributions to embryonic, visual, olfactory and wing development. We will also outline evidence for non-developmental functions of insect glia including blood-brain-barrier formation, homeostatic functions and potential contributions to synaptic function. Where relevant, we will also point out similarities between the functions of insect glia and their vertebrate counterparts.
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Affiliation(s)
- Robert J Parker
- Department of Zoology, University of British Columbia, 6270 University Blvd. Vancouver, BC, Canada V6T 1Z4
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