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Leier HC, Foden AJ, Jindal DA, Wilkov AJ, Van der Linden Costello P, Vanderzalm PJ, Coutinho-Budd JC, Tabuchi M, Broihier HT. Glia control experience-dependent plasticity in an olfactory critical period. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.07.05.602232. [PMID: 39005309 PMCID: PMC11245089 DOI: 10.1101/2024.07.05.602232] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/16/2024]
Abstract
Sensory experience during developmental critical periods has lifelong consequences for circuit function and behavior, but the molecular and cellular mechanisms through which experience causes these changes are not well understood. The Drosophila antennal lobe houses synapses between olfactory sensory neurons (OSNs) and downstream projection neurons (PNs) in stereotyped glomeruli. Many glomeruli exhibit structural plasticity in response to early-life odor exposure, indicating a general sensitivity of the fly olfactory circuitry to early sensory experience. We recently found that glia regulate the development of the antennal lobe in young adult flies, leading us to ask if glia also drive experience-dependent plasticity. Here we define a critical period for structural and functional plasticity of OSN-PN synapses in the ethyl butyrate (EB)-sensitive glomerulus VM7. EB exposure for the first two days post-eclosion drives large-scale reductions in glomerular volume, presynapse number, and post-synaptic activity. The highly conserved engulfment receptor Draper is required for this critical period plasticity. Specifically, ensheathing glia upregulate Draper expression, invade the VM7 glomerulus, and phagocytose OSN presynaptic terminals in response to critical-period EB exposure. Crucially, synapse pruning during the critical period has long-term consequences for circuit function since both OSN-PN synapse number and spontaneous activity of PNs remain persistently decreased. These data demonstrate experience-dependent pruning of synapses in olfactory circuitry and argue that the Drosophila antennal lobe will be a powerful model for defining the function of glia in critical period plasticity.
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2
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Contreras EG, Kautzmann S, Klämbt C. The Drosophila blood-brain barrier invades the nervous system in a GPCR-dependent manner. Front Cell Neurosci 2024; 18:1397627. [PMID: 38846639 PMCID: PMC11153769 DOI: 10.3389/fncel.2024.1397627] [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: 03/07/2024] [Accepted: 05/07/2024] [Indexed: 06/09/2024] Open
Abstract
The blood-brain barrier (BBB) represents a crucial interface between the circulatory system and the brain. In Drosophila melanogaster, the BBB is composed of perineurial and subperineurial glial cells. The perineurial glial cells are small mitotically active cells forming the outermost layer of the nervous system and are engaged in nutrient uptake. The subperineurial glial cells form occluding septate junctions to prevent paracellular diffusion of macromolecules into the nervous system. To address whether the subperineurial glia just form a simple barrier or whether they establish specific contacts with both the perineurial glial cells and inner central nervous system (CNS) cells, we undertook a detailed morphological analysis. Using genetically encoded markers alongside with high-resolution laser scanning confocal microscopy and transmission electron microscopy, we identified thin cell processes extending into the perineurial layer and into the CNS cortex. Interestingly, long cell processes were observed reaching the glia ensheathing the neuropil of the central brain. GFP reconstitution experiments highlighted multiple regions of membrane contacts between subperineurial and ensheathing glia. Furthermore, we identify the G-protein-coupled receptor (GPCR) Moody as negative regulator of the growth of subperineurial cell processes. Loss of moody triggered a massive overgrowth of subperineurial cell processes into the CNS cortex and, moreover, affected the polarized localization of the xenobiotic transporter Mdr65. Finally, we found that GPCR signaling, but not septate junction formation, is responsible for controlling membrane overgrowth. Our findings support the notion that the Drosophila BBB is able to bridge the communication gap between circulation and synaptic regions of the brain by long cell processes.
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Affiliation(s)
| | | | - Christian Klämbt
- Multiscale Imaging Center, Institute of Neuro- and Behavioral Biology, University of Münster, Münster, Germany
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3
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Yin J, Chen HL, Grigsby-Brown A, He Y, Cotten ML, Short J, Dermady A, Lei J, Gibbs M, Cheng ES, Zhang D, Long C, Xu L, Zhong T, Abzalimov R, Haider M, Sun R, He Y, Zhou Q, Tjandra N, Yuan Q. Glia-derived secretory fatty acid binding protein Obp44a regulates lipid storage and efflux in the developing Drosophila brain. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.04.10.588417. [PMID: 38645138 PMCID: PMC11030299 DOI: 10.1101/2024.04.10.588417] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/23/2024]
Abstract
Glia derived secretory factors play diverse roles in supporting the development, physiology, and stress responses of the central nervous system (CNS). Through transcriptomics and imaging analyses, we have identified Obp44a as one of the most abundantly produced secretory proteins from Drosophila CNS glia. Protein structure homology modeling and Nuclear Magnetic Resonance (NMR) experiments reveal Obp44a as a fatty acid binding protein (FABP) with a high affinity towards long-chain fatty acids in both native and oxidized forms. Further analyses demonstrate that Obp44a effectively infiltrates the neuropil, traffics between neuron and glia, and is secreted into hemolymph, acting as a lipid chaperone and scavenger to regulate lipid and redox homeostasis in the developing brain. In agreement with this essential role, deficiency of Obp44a leads to anatomical and behavioral deficits in adult animals and elevated oxidized lipid levels. Collectively, our findings unveil the crucial involvement of a noncanonical lipid chaperone to shuttle fatty acids within and outside the brain, as needed to maintain a healthy brain lipid environment. These findings could inspire the design of novel approaches to restore lipid homeostasis that is dysregulated in CNS diseases.
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Affiliation(s)
- Jun Yin
- Dendrite Morphogenesis and Plasticity Unit, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD
| | - Hsueh-Ling Chen
- Dendrite Morphogenesis and Plasticity Unit, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD
| | - Anna Grigsby-Brown
- Dendrite Morphogenesis and Plasticity Unit, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD
| | - Yi He
- Fermentation Facility, Biochemistry and Biophysics Center, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD
| | - Myriam L Cotten
- Department of Biochemistry and Biophysics, Oregon State University, Corvallis, OR
| | - Jacob Short
- Dendrite Morphogenesis and Plasticity Unit, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD
| | - Aidan Dermady
- Dendrite Morphogenesis and Plasticity Unit, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD
| | - Jingce Lei
- Dendrite Morphogenesis and Plasticity Unit, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD
| | - Mary Gibbs
- Dendrite Morphogenesis and Plasticity Unit, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD
| | - Ethan S Cheng
- Dendrite Morphogenesis and Plasticity Unit, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD
| | - Dean Zhang
- Dendrite Morphogenesis and Plasticity Unit, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD
| | - Caixia Long
- Dendrite Morphogenesis and Plasticity Unit, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD
| | - Lele Xu
- Advanced Science Research Center, The City University of New York, New York, NY
- Ph.D. Program in Biology, The Graduate Center of the City University of New York, New York, NY
| | - Tiffany Zhong
- Neuroscience Program, Princeton University, Princeton, NJ
| | - Rinat Abzalimov
- Advanced Science Research Center, The City University of New York, New York, NY
| | - Mariam Haider
- Department of Cell and Developmental Biology, Vanderbilt Brain Institute, Center for Structural Biology, Vanderbilt Kennedy Center, Vanderbilt University, Nashville, TN
| | - Rong Sun
- Department of Cell and Developmental Biology, Vanderbilt Brain Institute, Center for Structural Biology, Vanderbilt Kennedy Center, Vanderbilt University, Nashville, TN
| | - Ye He
- Advanced Science Research Center, The City University of New York, New York, NY
- Ph.D. Program in Biology, The Graduate Center of the City University of New York, New York, NY
| | - Qiangjun Zhou
- Department of Cell and Developmental Biology, Vanderbilt Brain Institute, Center for Structural Biology, Vanderbilt Kennedy Center, Vanderbilt University, Nashville, TN
| | - Nico Tjandra
- Laboratory of Molecular Biophysics, Biochemistry and Biophysics Center, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD
| | - Quan Yuan
- Dendrite Morphogenesis and Plasticity Unit, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD
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4
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Hewson L, Choo A, Webber DL, Trim PJ, Snel MF, Fedele AO, Hopwood JJ, Hemsley KM, O'Keefe LV. Drosophila melanogaster models of MPS IIIC (Hgsnat-deficiency) highlight the role of glia in disease presentation. J Inherit Metab Dis 2024; 47:340-354. [PMID: 38238109 DOI: 10.1002/jimd.12712] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/03/2023] [Revised: 12/18/2023] [Accepted: 12/21/2023] [Indexed: 03/16/2024]
Abstract
Sanfilippo syndrome (Mucopolysaccharidosis type III or MPS III) is a recessively inherited neurodegenerative lysosomal storage disorder. Mutations in genes encoding enzymes in the heparan sulphate degradation pathway lead to the accumulation of partially degraded heparan sulphate, resulting ultimately in the development of neurological deficits. Mutations in the gene encoding the membrane protein heparan-α-glucosaminide N-acetyltransferase (HGSNAT; EC2.3.1.78) cause MPS IIIC (OMIM#252930), typified by impaired cognition, sleep-wake cycle changes, hyperactivity and early death, often before adulthood. The precise disease mechanism that causes symptom emergence remains unknown, posing a significant challenge in the development of effective therapeutics. As HGSNAT is conserved in Drosophila melanogaster, we now describe the creation and characterisation of the first Drosophila models of MPS IIIC. Flies with either an endogenous insertion mutation or RNAi-mediated knockdown of hgsnat were confirmed to have a reduced level of HGSNAT transcripts and age-dependent accumulation of heparan sulphate leading to engorgement of the endo/lysosomal compartment. This resulted in abnormalities at the pre-synapse, defective climbing and reduced overall activity. Altered circadian rhythms (shift in peak morning activity) were seen in hgsnat neuronal knockdown lines. Further, when hgsnat was knocked down in specific glial subsets (wrapping, cortical, astrocytes or subperineural glia), impaired climbing or reduced activity was noted, implying that hgsnat function in these specific glial subtypes contributes significantly to this behaviour and targeting treatments to these cell groups may be necessary to ameliorate or prevent symptom onset. These novel models of MPS IIIC provide critical research tools for delineating the key cellular pathways causal in the onset of neurodegeneration in this presently untreatable disorder.
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Affiliation(s)
- Laura Hewson
- Department of Molecular and Biomedical Science, School of Biological Sciences, The University of Adelaide, Adelaide, South Australia, Australia
| | - Amanda Choo
- Department of Molecular and Biomedical Science, School of Biological Sciences, The University of Adelaide, Adelaide, South Australia, Australia
| | - Dani L Webber
- Department of Molecular and Biomedical Science, School of Biological Sciences, The University of Adelaide, Adelaide, South Australia, Australia
| | - Paul J Trim
- Proteomics, Metabolomics & MS-Imaging Core, South Australian Health and Medical Research Institute, Adelaide, South Australia, Australia
| | - Marten F Snel
- Proteomics, Metabolomics & MS-Imaging Core, South Australian Health and Medical Research Institute, Adelaide, South Australia, Australia
| | - Anthony O Fedele
- Hopwood Centre for Neurobiology, South Australian Health and Medical Research Institute, Adelaide, South Australia, Australia
| | - John J Hopwood
- Hopwood Centre for Neurobiology, South Australian Health and Medical Research Institute, Adelaide, South Australia, Australia
| | - Kim M Hemsley
- Childhood Dementia Research Group, Flinders Health and Medical Research Institute, Flinders University, Bedford Park, South Australia, Australia
| | - Louise V O'Keefe
- Department of Molecular and Biomedical Science, School of Biological Sciences, The University of Adelaide, Adelaide, South Australia, Australia
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5
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Chen J, Stork T, Kang Y, Nardone KAM, Auer F, Farrell RJ, Jay TR, Heo D, Sheehan A, Paton C, Nagel KI, Schoppik D, Monk KR, Freeman MR. Astrocyte growth is driven by the Tre1/S1pr1 phospholipid-binding G protein-coupled receptor. Neuron 2024; 112:93-112.e10. [PMID: 38096817 PMCID: PMC11073822 DOI: 10.1016/j.neuron.2023.11.008] [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: 01/10/2023] [Revised: 07/31/2023] [Accepted: 11/08/2023] [Indexed: 01/06/2024]
Abstract
Astrocytes play crucial roles in regulating neural circuit function by forming a dense network of synapse-associated membrane specializations, but signaling pathways regulating astrocyte morphogenesis remain poorly defined. Here, we show the Drosophila lipid-binding G protein-coupled receptor (GPCR) Tre1 is required for astrocytes to establish their intricate morphology in vivo. The lipid phosphate phosphatases Wunen/Wunen2 also regulate astrocyte morphology and, via Tre1, mediate astrocyte-astrocyte competition for growth-promoting lipids. Loss of s1pr1, the functional analog of Tre1 in zebrafish, disrupts astrocyte process elaboration, and live imaging and pharmacology demonstrate that S1pr1 balances proper astrocyte process extension/retraction dynamics during growth. Loss of Tre1 in flies or S1pr1 in zebrafish results in defects in simple assays of motor behavior. Tre1 and S1pr1 are thus potent evolutionarily conserved regulators of the elaboration of astrocyte morphological complexity and, ultimately, astrocyte control of behavior.
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Affiliation(s)
- Jiakun Chen
- Vollum Institute, Oregon Health & Science University, Portland, OR 97239, USA.
| | - Tobias Stork
- Vollum Institute, Oregon Health & Science University, Portland, OR 97239, USA
| | - Yunsik Kang
- Vollum Institute, Oregon Health & Science University, Portland, OR 97239, USA
| | - Katherine A M Nardone
- Departments of Otolaryngology and Neuroscience and Physiology, Neuroscience Institute, New York University Grossman School of Medicine, New York, NY 10016, USA
| | - Franziska Auer
- Departments of Otolaryngology and Neuroscience and Physiology, Neuroscience Institute, New York University Grossman School of Medicine, New York, NY 10016, USA
| | - Ryan J Farrell
- Neuroscience Institute, NYU Medical Center, New York, NY 10016, USA
| | - Taylor R Jay
- Vollum Institute, Oregon Health & Science University, Portland, OR 97239, USA
| | - Dongeun Heo
- Vollum Institute, Oregon Health & Science University, Portland, OR 97239, USA
| | - Amy Sheehan
- Vollum Institute, Oregon Health & Science University, Portland, OR 97239, USA
| | - Cameron Paton
- Vollum Institute, Oregon Health & Science University, Portland, OR 97239, USA
| | | | - David Schoppik
- Departments of Otolaryngology and Neuroscience and Physiology, Neuroscience Institute, New York University Grossman School of Medicine, New York, NY 10016, USA
| | - Kelly R Monk
- Vollum Institute, Oregon Health & Science University, Portland, OR 97239, USA.
| | - Marc R Freeman
- Vollum Institute, Oregon Health & Science University, Portland, OR 97239, USA.
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6
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Yadav V, Mishra R, Das P, Arya R. Cut homeodomain transcription factor is a novel regulator of growth and morphogenesis of cortex glia niche around neural cells. Genetics 2024; 226:iyad173. [PMID: 37751321 DOI: 10.1093/genetics/iyad173] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2023] [Revised: 09/12/2023] [Accepted: 09/13/2023] [Indexed: 09/28/2023] Open
Abstract
Cortex glia in Drosophila central nervous system form a niche around neural cells for necessary signals to establish cross talk with their surroundings. These cells grow and expand their thin processes around neural cell bodies. Although essential for the development and function of the nervous system, how these cells make extensive and intricate connected networks remains largely unknown. In this study, we show that Cut, a homeodomain transcription factor, directly regulates the fate of the cortex glia, impacting neural stem cell (NSC) homeostasis. Focusing on the thoracic ventral nerve cord, we found that Cut is required for the normal growth and development of cortex glia and timely increase in DNA content through endocycle to later divide via acytokinetic mitosis. Knockdown of Cut in cortex glia significantly reduces the growth of cellular processes, the network around NSCs, and their progeny's cell bodies. Conversely, overexpression of Cut induces overall growth of the main processes at the expense of side ones. Whereas the Cut knockdown slows down the timely increase of DNA, the Cut overexpression results in a significant increase in nuclear size and volume and a 3-fold increase in DNA content of cortex glia. Further, we note that constitutively high Cut also interfered with nuclei separation during acytokinetic mitosis. Since the cortex glia form syncytial networks around neural cells, the finding identifies Cut as a novel regulator of glial growth and variant cell cycles to support a functional nervous system.
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Affiliation(s)
- Vaishali Yadav
- Cytogenetics Laboratory, Department of Zoology, Institute of Science, Banaras Hindu University, Varanasi 221005, India
| | - Ramkrishna Mishra
- Cytogenetics Laboratory, Department of Zoology, Institute of Science, Banaras Hindu University, Varanasi 221005, India
| | - Papri Das
- Cytogenetics Laboratory, Department of Zoology, Institute of Science, Banaras Hindu University, Varanasi 221005, India
| | - Richa Arya
- Cytogenetics Laboratory, Department of Zoology, Institute of Science, Banaras Hindu University, Varanasi 221005, India
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7
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Valamparamban GF, Spéder P. Homemade: building the structure of the neurogenic niche. Front Cell Dev Biol 2023; 11:1275963. [PMID: 38107074 PMCID: PMC10722289 DOI: 10.3389/fcell.2023.1275963] [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: 08/10/2023] [Accepted: 11/16/2023] [Indexed: 12/19/2023] Open
Abstract
Neural stem/progenitor cells live in an intricate cellular environment, the neurogenic niche, which supports their function and enables neurogenesis. The niche is made of a diversity of cell types, including neurons, glia and the vasculature, which are able to signal to and are structurally organised around neural stem/progenitor cells. While the focus has been on how individual cell types signal to and influence the behaviour of neural stem/progenitor cells, very little is actually known on how the niche is assembled during development from multiple cellular origins, and on the role of the resulting topology on these cells. This review proposes to draw a state-of-the art picture of this emerging field of research, with the aim to expose our knowledge on niche architecture and formation from different animal models (mouse, zebrafish and fruit fly). We will span its multiple aspects, from the existence and importance of local, adhesive interactions to the potential emergence of larger-scale topological properties through the careful assembly of diverse cellular and acellular components.
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Affiliation(s)
| | - Pauline Spéder
- Institut Pasteur, Université Paris Cité, CNRS UMR3738, Structure and Signals in the Neurogenic Niche, Paris, France
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8
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Banach-Latapy A, Rincheval V, Briand D, Guénal I, Spéder P. Differential adhesion during development establishes individual neural stem cell niches and shapes adult behaviour in Drosophila. PLoS Biol 2023; 21:e3002352. [PMID: 37943883 PMCID: PMC10635556 DOI: 10.1371/journal.pbio.3002352] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2023] [Accepted: 09/28/2023] [Indexed: 11/12/2023] Open
Abstract
Neural stem cells (NSCs) reside in a defined cellular microenvironment, the niche, which supports the generation and integration of newborn neurons. The mechanisms building a sophisticated niche structure around NSCs and their functional relevance for neurogenesis are yet to be understood. In the Drosophila larval brain, the cortex glia (CG) encase individual NSC lineages in membranous chambers, organising the stem cell population and newborn neurons into a stereotypic structure. We first found that CG wrap around lineage-related cells regardless of their identity, showing that lineage information builds CG architecture. We then discovered that a mechanism of temporally controlled differential adhesion using conserved complexes supports the individual encasing of NSC lineages. An intralineage adhesion through homophilic Neuroglian interactions provides strong binding between cells of a same lineage, while a weaker interaction through Neurexin-IV and Wrapper exists between NSC lineages and CG. Loss of Neuroglian results in NSC lineages clumped together and in an altered CG network, while loss of Neurexin-IV/Wrapper generates larger yet defined CG chamber grouping several lineages together. Axonal projections of newborn neurons are also altered in these conditions. Further, we link the loss of these 2 adhesion complexes specifically during development to locomotor hyperactivity in the resulting adults. Altogether, our findings identify a belt of adhesions building a neurogenic niche at the scale of individual stem cell and provide the proof of concept that niche properties during development shape adult behaviour.
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Affiliation(s)
- Agata Banach-Latapy
- Institut Pasteur, Université Paris Cité, CNRS UMR3738, Structure and Signals in the Neurogenic Niche, Paris, France
| | | | - David Briand
- Institut Pasteur, Université Paris Cité, CNRS UMR3738, Structure and Signals in the Neurogenic Niche, Paris, France
| | - Isabelle Guénal
- Université Paris-Saclay, UVSQ, LGBC, 78000, Versailles, France
| | - Pauline Spéder
- Institut Pasteur, Université Paris Cité, CNRS UMR3738, Structure and Signals in the Neurogenic Niche, Paris, France
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9
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Baldenius M, Kautzmann S, Nanda S, Klämbt C. Signaling Pathways Controlling Axonal Wrapping in Drosophila. Cells 2023; 12:2553. [PMID: 37947631 PMCID: PMC10647682 DOI: 10.3390/cells12212553] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2023] [Revised: 10/24/2023] [Accepted: 10/27/2023] [Indexed: 11/12/2023] Open
Abstract
The rapid transmission of action potentials is an important ability that enables efficient communication within the nervous system. Glial cells influence conduction velocity along axons by regulating the radial axonal diameter, providing electrical insulation as well as affecting the distribution of voltage-gated ion channels. Differentiation of these wrapping glial cells requires a complex set of neuron-glia interactions involving three basic mechanistic features. The glia must recognize the axon, grow around it, and eventually arrest its growth to form single or multiple axon wraps. This likely depends on the integration of numerous evolutionary conserved signaling and adhesion systems. Here, we summarize the mechanisms and underlying signaling pathways that control glial wrapping in Drosophila and compare those to the mechanisms that control glial differentiation in mammals. This analysis shows that Drosophila is a beneficial model to study the development of even complex structures like myelin.
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Affiliation(s)
| | | | | | - Christian Klämbt
- Institute for Neuro- and Behavioral Biology, Faculty of Biology, University of Münster, Röntgenstraße 16, D-48149 Münster, Germany; (M.B.)
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10
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Merighi A, Lossi L. Co-cultures of cerebellar slices from mice with different reelin genetic backgrounds as a model to study cortical lamination. F1000Res 2023; 11:1183. [PMID: 37881513 PMCID: PMC10594056 DOI: 10.12688/f1000research.126787.1] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 09/07/2023] [Indexed: 10/27/2023] Open
Abstract
Background: Reelin has fundamental functions in the developing and mature brain. Its absence gives rise to the Reeler phenotype in mice, the first described cerebellar mutation. In homozygous mutants missing the Reelin gene ( reln -/-), neurons are incapable of correctly positioning themselves in layered brain areas such as the cerebral and cerebellar cortices. We here demonstrate that by employing ex vivo cultured cerebellar slices one can reduce the number of animals and use a non-recovery procedure to analyze the effects of Reelin on the migration of Purkinje neurons (PNs). Methods: We generated mouse hybrids (L7-GFP relnF1/) with green fluorescent protein (GFP)-tagged PNs, directly visible under fluorescence microscopy. We then cultured the slices obtained from mice with different reln genotypes and demonstrated that when the slices from reln -/- mutants were co-cultured with those from reln +/- mice, the Reelin produced by the latter induced migration of the PNs to partially rescue the normal layered cortical histology. We have confirmed this observation with Voronoi tessellation to analyze PN dispersion. Results: In images of the co-cultured slices from reln -/- mice, Voronoi polygons were larger than in single-cultured slices of the same genetic background but smaller than those generated from slices of reln +/- animals. The mean roundness factor, area disorder, and roundness factor homogeneity were different when slices from reln -/- mice were cultivated singularly or co-cultivated, supporting mathematically the transition from the clustered organization of the PNs in the absence of Reelin to a layered structure when the protein is supplied ex vivo. Conclusions: Neurobiologists are the primary target users of this 3Rs approach. They should adopt it for the possibility to study and manipulate ex vivo the activity of a brain-secreted or genetically engineered protein (scientific perspective), the potential reduction (up to 20%) of the animals used, and the total avoidance of severe surgery (3Rs perspective).
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Affiliation(s)
- Adalberto Merighi
- Department of Veterinary Sciences, University of Turin, Grugliasco, 10095, Italy
| | - Laura Lossi
- Department of Veterinary Sciences, University of Turin, Grugliasco, 10095, Italy
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11
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Lago-Baldaia I, Cooper M, Seroka A, Trivedi C, Powell GT, Wilson SW, Ackerman SD, Fernandes VM. A Drosophila glial cell atlas reveals a mismatch between transcriptional and morphological diversity. PLoS Biol 2023; 21:e3002328. [PMID: 37862379 PMCID: PMC10619882 DOI: 10.1371/journal.pbio.3002328] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2023] [Revised: 11/01/2023] [Accepted: 09/08/2023] [Indexed: 10/22/2023] Open
Abstract
Morphology is a defining feature of neuronal identity. Like neurons, glia display diverse morphologies, both across and within glial classes, but are also known to be morphologically plastic. Here, we explored the relationship between glial morphology and transcriptional signature using the Drosophila central nervous system (CNS), where glia are categorised into 5 main classes (outer and inner surface glia, cortex glia, ensheathing glia, and astrocytes), which show within-class morphological diversity. We analysed and validated single-cell RNA sequencing data of Drosophila glia in 2 well-characterised tissues from distinct developmental stages, containing distinct circuit types: the embryonic ventral nerve cord (VNC) (motor) and the adult optic lobes (sensory). Our analysis identified a new morphologically and transcriptionally distinct surface glial population in the VNC. However, many glial morphological categories could not be distinguished transcriptionally, and indeed, embryonic and adult astrocytes were transcriptionally analogous despite differences in developmental stage and circuit type. While we did detect extensive within-class transcriptomic diversity for optic lobe glia, this could be explained entirely by glial residence in the most superficial neuropil (lamina) and an associated enrichment for immune-related gene expression. In summary, we generated a single-cell transcriptomic atlas of glia in Drosophila, and our extensive in vivo validation revealed that glia exhibit more diversity at the morphological level than was detectable at the transcriptional level. This atlas will serve as a resource for the community to probe glial diversity and function.
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Affiliation(s)
- Inês Lago-Baldaia
- Department of Cell and Developmental Biology, University College London, London, United Kingdom
| | - Maia Cooper
- Department of Cell and Developmental Biology, University College London, London, United Kingdom
| | - Austin Seroka
- Institute of Neuroscience, Howard Hughes Medical Institute, University of Oregon, Eugene, Oregon, United States of America
| | - Chintan Trivedi
- Department of Cell and Developmental Biology, University College London, London, United Kingdom
| | - Gareth T. Powell
- Department of Cell and Developmental Biology, University College London, London, United Kingdom
| | - Stephen W. Wilson
- Department of Cell and Developmental Biology, University College London, London, United Kingdom
| | - Sarah D. Ackerman
- Department of Pathology and Immunology, Brain Immunology and Glia Center, Washington University School of Medicine, Saint Louis, Missouri, United States of America
- Department of Developmental Biology, Washington University School of Medicine, Saint Louis, Missouri, United States of America
| | - Vilaiwan M. Fernandes
- Department of Cell and Developmental Biology, University College London, London, United Kingdom
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12
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Chandra B, Voas MG, Davies EL, Roberts-Galbraith RH. Ets-1 transcription factor regulates glial cell regeneration and function in planarians. Development 2023; 150:dev201666. [PMID: 37665145 PMCID: PMC10508700 DOI: 10.1242/dev.201666] [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: 02/01/2023] [Accepted: 08/15/2023] [Indexed: 09/05/2023]
Abstract
Glia play multifaceted roles in nervous systems in response to injury. Depending on the species, extent of injury and glial cell type in question, glia can help or hinder the regeneration of neurons. Studying glia in the context of successful regeneration could reveal features of pro-regenerative glia that could be exploited for new human therapies. Planarian flatworms completely regenerate their nervous systems after injury - including glia - and thus provide a strong model system for exploring glia in the context of regeneration. Here, we report that planarian glia regenerate after neurons, and that neurons are required for correct glial numbers and localization during regeneration. We also identify the planarian transcription factor-encoding gene ets-1 as a key regulator of glial cell maintenance and regeneration. Using ets-1 (RNAi) to perturb glia, we show that glial loss is associated with altered neuronal gene expression, impeded animal movement and impaired nervous system architecture - particularly within the neuropil. Importantly, our work reveals the inter-relationships of glia and neurons in the context of robust neural regeneration.
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Affiliation(s)
- Bidushi Chandra
- Department of Cellular Biology, University of Georgia, Athens, GA 30602, USA
| | - Matthew G. Voas
- Center for Cancer Research, National Cancer Institute, National Institutes of Health, Frederick, MD 21702, USA
| | - Erin L. Davies
- Center for Cancer Research, National Cancer Institute, National Institutes of Health, Frederick, MD 21702, USA
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13
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Corty MM, Coutinho-Budd J. Drosophila glia take shape to sculpt the nervous system. Curr Opin Neurobiol 2023; 79:102689. [PMID: 36822142 PMCID: PMC10023329 DOI: 10.1016/j.conb.2023.102689] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2022] [Revised: 12/19/2022] [Accepted: 01/10/2023] [Indexed: 02/23/2023]
Abstract
The importance of glial cells has become increasingly apparent over the past 20 years, yet compared to neurons we still know relatively little about these essential cells. Most critical glial cell functions are conserved in Drosophila glia, often using the same key molecular players as their vertebrate counterparts. The relative simplicity of the Drosophila nervous system, combined with a vast array of powerful genetic tools, allows us to further dissect the molecular composition and functional roles of glia in ways that would be much more cumbersome or not possible in higher vertebrate systems. Importantly, Drosophila genetics allow for in vivo manipulation, and their transparent body wall enables in vivo imaging of glia in intact animals throughout early development. Here we discuss recent advances in Drosophila glial development detailing how these cells take on their mature morphologies and interact with neurons to perform their important functional roles in the nervous system.
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Affiliation(s)
- Megan M Corty
- Vollum Institute, Oregon Health & Science University, Portland, OR, USA. https://twitter.com/@megancphd
| | - Jaeda Coutinho-Budd
- Department of Neuroscience, University of Virginia, Charlottesville, VA, USA.
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14
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Markey KM, Saunders JC, Smuts J, von Reyn CR, Garcia ADR. Astrocyte development—More questions than answers. Front Cell Dev Biol 2023; 11:1063843. [PMID: 37051466 PMCID: PMC10083403 DOI: 10.3389/fcell.2023.1063843] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2022] [Accepted: 03/14/2023] [Indexed: 03/28/2023] Open
Abstract
The past 15–20 years has seen a remarkable shift in our understanding of astrocyte contributions to central nervous system (CNS) function. Astrocytes have emerged from the shadows of neuroscience and are now recognized as key elements in a broad array of CNS functions. Astrocytes comprise a substantial fraction of cells in the human CNS. Nevertheless, fundamental questions surrounding their basic biology remain poorly understood. While recent studies have revealed a diversity of essential roles in CNS function, from synapse formation and function to blood brain barrier maintenance, fundamental mechanisms of astrocyte development, including their expansion, migration, and maturation, remain to be elucidated. The coincident development of astrocytes and synapses highlights the need to better understand astrocyte development and will facilitate novel strategies for addressing neurodevelopmental and neurological dysfunction. In this review, we provide an overview of the current understanding of astrocyte development, focusing primarily on mammalian astrocytes and highlight outstanding questions that remain to be addressed. We also include an overview of Drosophila glial development, emphasizing astrocyte-like glia given their close anatomical and functional association with synapses. Drosophila offer an array of sophisticated molecular genetic tools and they remain a powerful model for elucidating fundamental cellular and molecular mechanisms governing astrocyte development. Understanding the parallels and distinctions between astrocyte development in Drosophila and vertebrates will enable investigators to leverage the strengths of each model system to gain new insights into astrocyte function.
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Affiliation(s)
- Kathryn M. Markey
- Department of Biology, Drexel University, Philadelphia, PA, United States
| | | | - Jana Smuts
- Department of Neurobiology and Anatomy, Drexel University, Philadelphia, PA, United States
| | - Catherine R. von Reyn
- Department of Neurobiology and Anatomy, Drexel University, Philadelphia, PA, United States
- School of Biomedical Engineering, Science and Health Systems, Drexel University, Philadelphia, PA, United States
| | - A. Denise R. Garcia
- Department of Biology, Drexel University, Philadelphia, PA, United States
- Department of Neurobiology and Anatomy, Drexel University, Philadelphia, PA, United States
- *Correspondence: A. Denise R. Garcia,
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15
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Ma M, Zhang X, Zheng Y, Lu S, Pan X, Mao X, Pan H, Chung HL, Wang H, Guo H, Bellen HJ. The fly homolog of SUPT16H, a gene associated with neurodevelopmental disorders, is required in a cell-autonomous fashion for cell survival. Hum Mol Genet 2023; 32:984-997. [PMID: 36255738 PMCID: PMC9991001 DOI: 10.1093/hmg/ddac259] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2022] [Revised: 09/22/2022] [Accepted: 10/14/2022] [Indexed: 11/14/2022] Open
Abstract
SUPT16H encodes the large subunit of the FAcilitate Chromatin Transcription (FACT) complex, which functions as a nucleosome organizer during transcription. We identified two individuals from unrelated families carrying de novo missense variants in SUPT16H. The probands exhibit global developmental delay, intellectual disability, epilepsy, facial dysmorphism and brain structural abnormalities. We used Drosophila to characterize two variants: p.T171I and p.G808R. Loss of the fly ortholog, dre4, causes lethality at an early developmental stage. RNAi-mediated knockdown of dre4 in either glia or neurons causes severely reduced eclosion and longevity. Tissue-specific knockdown of dre4 in the eye or wing leads to the loss of these tissues, whereas overexpression of SUPT16H has no dominant effect. Moreover, expression of the reference SUPT16H significantly rescues the loss-of-function phenotypes in the nervous system as well as wing and eye. In contrast, expression of SUPT16H p.T171I or p.G808R rescues the phenotypes poorly, indicating that the variants are partial loss-of-function alleles. While previous studies argued that the developmental arrest caused by loss of dre4 is due to impaired ecdysone production in the prothoracic gland, our data show that dre4 is required for proper cell growth and survival in multiple tissues in a cell-autonomous manner. Altogether, our data indicate that the de novo loss-of-function variants in SUPT16H are indeed associated with developmental and neurological defects observed in the probands.
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Affiliation(s)
- Mengqi Ma
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA
- Jan and Dan Duncan Neurological Research Institute, Texas Children's Hospital, Houston, TX 77030, USA
| | - Xi Zhang
- National Health Commission Key Laboratory of Birth Defects Research, Prevention and Treatment, Hunan Provincial Maternal and Child Health Care Hospital, Changsha, Hunan 410008, China
- Department of Neurology, Xiangya Hospital, Central South University, Changsha, Hunan 410008, China
| | - Yiming Zheng
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA
- Jan and Dan Duncan Neurological Research Institute, Texas Children's Hospital, Houston, TX 77030, USA
| | - Shenzhao Lu
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA
- Jan and Dan Duncan Neurological Research Institute, Texas Children's Hospital, Houston, TX 77030, USA
| | - Xueyang Pan
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA
- Jan and Dan Duncan Neurological Research Institute, Texas Children's Hospital, Houston, TX 77030, USA
| | - Xiao Mao
- National Health Commission Key Laboratory of Birth Defects Research, Prevention and Treatment, Hunan Provincial Maternal and Child Health Care Hospital, Changsha, Hunan 410008, China
- Department of Medical Genetics, Maternal and Child Health Hospital of Hunan Province, Changsha, Hunan 410008, China
| | - Hongling Pan
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA
- Jan and Dan Duncan Neurological Research Institute, Texas Children's Hospital, Houston, TX 77030, USA
| | - Hyung-lok Chung
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA
- Jan and Dan Duncan Neurological Research Institute, Texas Children's Hospital, Houston, TX 77030, USA
| | - Hua Wang
- National Health Commission Key Laboratory of Birth Defects Research, Prevention and Treatment, Hunan Provincial Maternal and Child Health Care Hospital, Changsha, Hunan 410008, China
- Department of Medical Genetics, Hunan Children’s Hospital, Changsha, Hunan 410007, China
| | - Hong Guo
- Department of Medical Genetics, Army Medical University, Chongqing 400038, China
| | - Hugo J Bellen
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA
- Jan and Dan Duncan Neurological Research Institute, Texas Children's Hospital, Houston, TX 77030, USA
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16
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Lassetter AP, Corty MM, Barria R, Sheehan AE, Hill JQ, Aicher SA, Fox AN, Freeman MR. Glial TGFβ activity promotes neuron survival in peripheral nerves. J Cell Biol 2023; 222:e202111053. [PMID: 36399182 PMCID: PMC9679965 DOI: 10.1083/jcb.202111053] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2021] [Revised: 09/06/2022] [Accepted: 10/26/2022] [Indexed: 11/19/2022] Open
Abstract
Maintaining long, energetically demanding axons throughout the life of an animal is a major challenge for the nervous system. Specialized glia ensheathe axons and support their function and integrity throughout life, but glial support mechanisms remain poorly defined. Here, we identified a collection of secreted and transmembrane molecules required in glia for long-term axon survival in vivo. We showed that the majority of components of the TGFβ superfamily are required in glia for sensory neuron maintenance but not glial ensheathment of axons. In the absence of glial TGFβ signaling, neurons undergo age-dependent degeneration that can be rescued either by genetic blockade of Wallerian degeneration or caspase-dependent death. Blockade of glial TGFβ signaling results in increased ATP in glia that can be mimicked by enhancing glial mitochondrial biogenesis or suppressing glial monocarboxylate transporter function. We propose that glial TGFβ signaling supports axon survival and suppresses neurodegeneration through promoting glial metabolic support of neurons.
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Affiliation(s)
| | - Megan M. Corty
- Vollum Institute, Oregon Health & Science University, Portland, OR
| | - Romina Barria
- Vollum Institute, Oregon Health & Science University, Portland, OR
| | - Amy E. Sheehan
- Vollum Institute, Oregon Health & Science University, Portland, OR
| | - Jo Q. Hill
- Department of Chemical Physiology & Biochemistry, Oregon Health & Science University, Portland, OR
| | - Sue A. Aicher
- Department of Chemical Physiology & Biochemistry, Oregon Health & Science University, Portland, OR
| | - A. Nicole Fox
- University of Massachusetts Medical School, Worcester, MA
| | - Marc R. Freeman
- Vollum Institute, Oregon Health & Science University, Portland, OR
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17
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Dillon ST, Otu HH, Ngo LH, Fong TG, Vasunilashorn SM, Xie Z, Kunze LJ, Vlassakov KV, Abdeen A, Lange JK, Earp BE, Cooper ZR, Schmitt E, Arnold SE, Hshieh T, Jones RN, Inouye SK, Marcantonio ER, Libermann TA. Patterns and Persistence of Perioperative Plasma and Cerebrospinal Fluid Neuroinflammatory Protein Biomarkers After Elective Orthopedic Surgery Using SOMAscan. Anesth Analg 2023; 136:163-175. [PMID: 35389379 PMCID: PMC9537343 DOI: 10.1213/ane.0000000000005991] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
BACKGROUND The neuroinflammatory response to surgery can be characterized by peripheral acute plasma protein changes in blood, but corresponding, persisting alterations in cerebrospinal fluid (CSF) proteins remain mostly unknown. Using the SOMAscan assay, we define acute and longer-term proteome changes associated with surgery in plasma and CSF. We hypothesized that biological pathways identified by these proteins would be in the categories of neuroinflammation and neuronal function and define neuroinflammatory proteome changes associated with surgery in older patients. METHODS SOMAscan analyzed 1305 proteins in blood plasma (n = 14) and CSF (n = 15) samples from older patients enrolled in the Role of Inflammation after Surgery for Elders (RISE) study undergoing elective hip and knee replacement surgery with spinal anesthesia. Systems biology analysis identified biological pathways enriched among the surgery-associated differentially expressed proteins in plasma and CSF. RESULTS Comparison of postoperative day 1 (POD1) to preoperative (PREOP) plasma protein levels identified 343 proteins with postsurgical changes ( P < .05; absolute value of the fold change [|FC|] > 1.2). Comparing postoperative 1-month (PO1MO) plasma and CSF with PREOP identified 67 proteins in plasma and 79 proteins in CSF with altered levels ( P < .05; |FC| > 1.2). In plasma, 21 proteins, primarily linked to immune response and inflammation, were similarly changed at POD1 and PO1MO. Comparison of plasma to CSF at PO1MO identified 8 shared proteins. Comparison of plasma at POD1 to CSF at PO1MO identified a larger number, 15 proteins in common, most of which are regulated by interleukin-6 (IL-6) or transforming growth factor beta-1 (TGFB1) and linked to the inflammatory response. Of the 79 CSF PO1MO-specific proteins, many are involved in neuronal function and neuroinflammation. CONCLUSIONS SOMAscan can characterize both short- and long-term surgery-induced protein alterations in plasma and CSF. Acute plasma protein changes at POD1 parallel changes in PO1MO CSF and suggest 15 potential biomarkers for longer-term neuroinflammation that warrant further investigation.
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Affiliation(s)
- Simon T. Dillon
- Division of Interdisciplinary Medicine and Biotechnology, Beth Israel Deaconess Medical Center, Boston, MA
- Beth Israel Deaconess Medical Center Genomics, Proteomics, Bioinformatics and Systems Biology Center, Boston, MA
- Harvard Medical School, Boston, MA
| | | | - Long H. Ngo
- Harvard Medical School, Boston, MA
- Divisions of General Medicine, Beth Israel Deaconess Medical Center, Boston, MA
| | - Tamara G. Fong
- Harvard Medical School, Boston, MA
- Department of Neurology, Beth Israel Deaconess Medical Center, Boston, MA
- Aging Brain Center, Marcus Institute for Aging Research, Hebrew SeniorLife, Boston, MA
| | - Sarinnapha M. Vasunilashorn
- Harvard Medical School, Boston, MA
- Divisions of General Medicine, Beth Israel Deaconess Medical Center, Boston, MA
- Departments of Epidemiology and Biostatistics, Harvard T.H. Chan School of Public Health, Boston, MA
| | - Zhongcong Xie
- Harvard Medical School, Boston, MA
- Department of Anesthesia, Critical Care and Pain Medicine, Massachusetts General Hospital, Boston, MA
| | - Lisa J. Kunze
- Harvard Medical School, Boston, MA
- Department of Anesthesia, Critical Care and Pain Medicine, Beth Israel Deaconess Medical Center, Boston, MA
| | - Kamen V. Vlassakov
- Harvard Medical School, Boston, MA
- Department of Anesthesiology, Perioperative and Pain Medicine, Brigham and Women’s Hospital, Boston, MA
| | - Ayesha Abdeen
- Harvard Medical School, Boston, MA
- Department of Orthopedic Surgery, Beth Israel Deaconess Medical Center, Boston, MA
| | - Jeffrey K. Lange
- Harvard Medical School, Boston, MA
- Department of Orthopedic Surgery, Brigham and Women’s Hospital, Boston, MA
| | - Brandon E. Earp
- Harvard Medical School, Boston, MA
- Department of Orthopedic Surgery, Brigham and Women’s Faulkner Hospital, Boston, MA
| | - Zara R. Cooper
- Harvard Medical School, Boston, MA
- Department of Surgery, Brigham and Women’s Hospital, Boston, MA
| | - Eva Schmitt
- Aging Brain Center, Marcus Institute for Aging Research, Hebrew SeniorLife, Boston, MA
| | - Steven E. Arnold
- MGH Institute for Neurodegenerative Disease, Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA
| | - Tammy Hshieh
- Harvard Medical School, Boston, MA
- Aging Brain Center, Marcus Institute for Aging Research, Hebrew SeniorLife, Boston, MA
- Divisions of General Medicine, Beth Israel Deaconess Medical Center, Boston, MA
| | - Richard N. Jones
- Departments of Psychiatry and Human Behavior and Neurology, Warren Alpert Medical School, Brown University, Providence, RI, USA
| | - Sharon K. Inouye
- Harvard Medical School, Boston, MA
- Aging Brain Center, Marcus Institute for Aging Research, Hebrew SeniorLife, Boston, MA
- Gerontology, Department of Medicine, Beth Israel Deaconess Medical Center, Boston, MA
| | - Edward R. Marcantonio
- Harvard Medical School, Boston, MA
- Divisions of General Medicine, Beth Israel Deaconess Medical Center, Boston, MA
- Gerontology, Department of Medicine, Beth Israel Deaconess Medical Center, Boston, MA
| | - Towia A. Libermann
- Division of Interdisciplinary Medicine and Biotechnology, Beth Israel Deaconess Medical Center, Boston, MA
- Beth Israel Deaconess Medical Center Genomics, Proteomics, Bioinformatics and Systems Biology Center, Boston, MA
- Harvard Medical School, Boston, MA
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18
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Corty MM, Hulegaard AL, Hill JQ, Sheehan AE, Aicher SA, Freeman MR. Discoidin domain receptor regulates ensheathment, survival and caliber of peripheral axons. Development 2022; 149:281293. [PMID: 36355066 PMCID: PMC10112903 DOI: 10.1242/dev.200636] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2022] [Accepted: 10/27/2022] [Indexed: 11/12/2022]
Abstract
Most invertebrate axons and small-caliber axons in mammalian peripheral nerves are unmyelinated but still ensheathed by glia. Here, we use Drosophila wrapping glia to study the development and function of non-myelinating axon ensheathment, which is poorly understood. Selective ablation of these glia from peripheral nerves severely impaired larval locomotor behavior. In an in vivo RNA interference screen to identify glial genes required for axon ensheathment, we identified the conserved receptor tyrosine kinase Discoidin domain receptor (Ddr). In larval peripheral nerves, loss of Ddr resulted in severely reduced ensheathment of axons and reduced axon caliber, and we found a strong dominant genetic interaction between Ddr and the type XV/XVIII collagen Multiplexin (Mp), suggesting that Ddr functions as a collagen receptor to drive axon wrapping. In adult nerves, loss of Ddr decreased long-term survival of sensory neurons and significantly reduced axon caliber without overtly affecting ensheathment. Our data establish essential roles for non-myelinating glia in nerve development, maintenance and function, and identify Ddr as a key regulator of axon-glia interactions during ensheathment and establishment of axon caliber.
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Affiliation(s)
- Megan M Corty
- Vollum Institute, Oregon Health & Science University, Portland, OR 97239, USA
| | | | - Jo Q Hill
- Department of Chemical Physiology & Biochemistry, Oregon Health & Science University, Portland, OR 97239, USA
| | - Amy E Sheehan
- Vollum Institute, Oregon Health & Science University, Portland, OR 97239, USA
| | - Sue A Aicher
- Department of Chemical Physiology & Biochemistry, Oregon Health & Science University, Portland, OR 97239, USA
| | - Marc R Freeman
- Vollum Institute, Oregon Health & Science University, Portland, OR 97239, USA
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19
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De Backer JF, Grunwald Kadow IC. A role for glia in cellular and systemic metabolism: insights from the fly. CURRENT OPINION IN INSECT SCIENCE 2022; 53:100947. [PMID: 35772690 DOI: 10.1016/j.cois.2022.100947] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/15/2022] [Revised: 06/18/2022] [Accepted: 06/20/2022] [Indexed: 06/15/2023]
Abstract
Excitability and synaptic transmission make neurons high-energy consumers. However, neurons do not store carbohydrates or lipids. Instead, they need support cells to fuel their metabolic demands. This role is assumed by glia, both in vertebrates and invertebrates. Many questions remain regarding the coupling between neuronal activity and energy demand on the one hand, and nutrient supply by glia on the other hand. Here, we review recent advances showing that fly glia, similar to their role in vertebrates, fuel neurons in times of high energetic demand, such as during memory formation and long-term storage. Vertebrate glia also play a role in the modulation of neurons, their communication, and behavior, including food search and feeding. We discuss recent literature pointing to similar roles of fly glia in behavior and metabolism.
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Affiliation(s)
- Jean-François De Backer
- Technical University of Munich, School of Life Sciences, Liesel-Beckmann-Str. 4, 85354 Freising, Germany; University of Bonn, Faculty of Medicine, UKB, Institute of Physiology II, Nussallee 11, 53115 Bonn, Germany
| | - Ilona C Grunwald Kadow
- Technical University of Munich, School of Life Sciences, Liesel-Beckmann-Str. 4, 85354 Freising, Germany; University of Bonn, Faculty of Medicine, UKB, Institute of Physiology II, Nussallee 11, 53115 Bonn, Germany.
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20
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An interplay between cellular growth and atypical fusion defines morphogenesis of a modular glial niche in Drosophila. Nat Commun 2022; 13:4999. [PMID: 36008397 PMCID: PMC9411534 DOI: 10.1038/s41467-022-32685-3] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2021] [Accepted: 08/10/2022] [Indexed: 11/16/2022] Open
Abstract
Neural stem cells (NSCs) live in an intricate cellular microenvironment supporting their activity, the niche. Whilst shape and function are inseparable, the morphogenetic aspects of niche development are poorly understood. Here, we use the formation of a glial niche to investigate acquisition of architectural complexity. Cortex glia (CG) in Drosophila regulate neurogenesis and build a reticular structure around NSCs. We first show that individual CG cells grow tremendously to ensheath several NSC lineages, employing elaborate proliferative mechanisms which convert these cells into syncytia rich in cytoplasmic bridges. CG syncytia further undergo homotypic cell–cell fusion, using defined cell surface receptors and actin regulators. Cellular exchange is however dynamic in space and time. This atypical cell fusion remodels cellular borders, restructuring the CG syncytia. Ultimately, combined growth and fusion builds the multi-level architecture of the niche, and creates a modular, spatial partition of the NSC population. Our findings provide insights into how a niche forms and organises while developing intimate contacts with a stem cell population. Little is known of how the architectural complexity of the neural stem cell niche is achieved. Rujano et al. show that the morphogenesis of a glial niche in Drosophila involves complex proliferative strategies and atypical cell–cell fusion.
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21
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Rey S, Ohm H, Klämbt C. Axonal ion homeostasis and glial differentiation. FEBS J 2022. [PMID: 35943294 DOI: 10.1111/febs.16594] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2022] [Revised: 07/26/2022] [Accepted: 08/08/2022] [Indexed: 11/27/2022]
Abstract
The brain is the ultimate control unit of the body. It conducts accurate, fast and reproducible calculations to control motor actions affecting mating, foraging and flight or fight decisions. Therefore, during evolution, better and more efficient brains have emerged. However, even simple brains are complex organs. They are formed by glial cells and neurons that establish highly intricate networks to enable information collection, processing and eventually, a precise motor control. Here, we review and connect some well-established and some hidden pieces of information to set the focus on ion homeostasis as a driving force in glial differentiation promoting signalling speed and accuracy.
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Affiliation(s)
- Simone Rey
- Institut für Neuro‐ und Verhaltensbiologie Münster Germany
| | - Henrike Ohm
- Institut für Neuro‐ und Verhaltensbiologie Münster Germany
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22
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Herrmann KA, Liu Y, Llobet-Rosell A, McLaughlin CN, Neukomm LJ, Coutinho-Budd JC, Broihier HT. Divergent signaling requirements of dSARM in injury-induced degeneration and developmental glial phagocytosis. PLoS Genet 2022; 18:e1010257. [PMID: 35737721 PMCID: PMC9223396 DOI: 10.1371/journal.pgen.1010257] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2022] [Accepted: 05/13/2022] [Indexed: 02/06/2023] Open
Abstract
Elucidating signal transduction mechanisms of innate immune pathways is essential to defining how they elicit distinct cellular responses. Toll-like receptors (TLR) signal through their cytoplasmic TIR domains which bind other TIR domain-containing adaptors. dSARM/SARM1 is one such TIR domain adaptor best known for its role as the central axon degeneration trigger after injury. In degeneration, SARM1's domains have been assigned unique functions: the ARM domain is auto-inhibitory, SAM-SAM domain interactions mediate multimerization, and the TIR domain has intrinsic NAD+ hydrolase activity that precipitates axonal demise. Whether and how these distinct functions contribute to TLR signaling is unknown. Here we show divergent signaling requirements for dSARM in injury-induced axon degeneration and TLR-mediated developmental glial phagocytosis through analysis of new knock-in domain and point mutations. We demonstrate intragenic complementation between reciprocal pairs of domain mutants during development, providing evidence for separability of dSARM functional domains in TLR signaling. Surprisingly, dSARM's NAD+ hydrolase activity is strictly required for both degenerative and developmental signaling, demonstrating that TLR signal transduction requires dSARM's enzymatic activity. In contrast, while SAM domain-mediated dSARM multimerization is important for axon degeneration, it is dispensable for TLR signaling. Finally, dSARM functions in a linear genetic pathway with the MAP3K Ask1 during development but not in degenerating axons. Thus, we propose that dSARM exists in distinct signaling states in developmental and pathological contexts.
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Affiliation(s)
- Kelsey A. Herrmann
- Department of Neurosciences, Case Western Reserve University School of Medicine, Cleveland, Ohio, United States of America
| | - Yizhou Liu
- Department of Neurosciences, Case Western Reserve University School of Medicine, Cleveland, Ohio, United States of America
| | - Arnau Llobet-Rosell
- Department of Fundamental Neurosciences, University of Lausanne, Lausanne, Switzerland
| | - Colleen N. McLaughlin
- Department of Neurosciences, Case Western Reserve University School of Medicine, Cleveland, Ohio, United States of America
| | - Lukas J. Neukomm
- Department of Fundamental Neurosciences, University of Lausanne, Lausanne, Switzerland
| | - Jaeda C. Coutinho-Budd
- Department of Neuroscience, University of Virginia, Charlottesville, Virginia, United States of America
| | - Heather T. Broihier
- Department of Neurosciences, Case Western Reserve University School of Medicine, Cleveland, Ohio, United States of America
- * E-mail:
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23
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Nguyen PK, Cheng LY. Non-autonomous regulation of neurogenesis by extrinsic cues: a Drosophila perspective. OXFORD OPEN NEUROSCIENCE 2022; 1:kvac004. [PMID: 38596708 PMCID: PMC10913833 DOI: 10.1093/oons/kvac004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/14/2022] [Revised: 03/20/2022] [Accepted: 03/23/2022] [Indexed: 04/11/2024]
Abstract
The formation of a functional circuitry in the central nervous system (CNS) requires the correct number and subtypes of neural cells. In the developing brain, neural stem cells (NSCs) self-renew while giving rise to progenitors that in turn generate differentiated progeny. As such, the size and the diversity of cells that make up the functional CNS depend on the proliferative properties of NSCs. In the fruit fly Drosophila, where the process of neurogenesis has been extensively investigated, extrinsic factors such as the microenvironment of NSCs, nutrients, oxygen levels and systemic signals have been identified as regulators of NSC proliferation. Here, we review decades of work that explores how extrinsic signals non-autonomously regulate key NSC characteristics such as quiescence, proliferation and termination in the fly.
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Affiliation(s)
- Phuong-Khanh Nguyen
- Peter MacCallum Cancer Centre, Melbourne, Victoria 3000, Australia
- Department of Anatomy and Physiology, The University of Melbourne, Victoria 3010, Australia
| | - Louise Y Cheng
- Peter MacCallum Cancer Centre, Melbourne, Victoria 3000, Australia
- Sir Peter MacCallum Department of Oncology, The University of Melbourne, Victoria 3010, Australia
- Department of Anatomy and Physiology, The University of Melbourne, Victoria 3010, Australia
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24
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Salazar G, Ross G, Maserejian AE, Coutinho-Budd J. Quantifying Glial-Glial Tiling Using Automated Image Analysis in Drosophila. Front Cell Neurosci 2022; 16:826483. [PMID: 35401121 PMCID: PMC8987577 DOI: 10.3389/fncel.2022.826483] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2021] [Accepted: 01/31/2022] [Indexed: 11/20/2022] Open
Abstract
Not only do glia form close associations with neurons throughout the central nervous system (CNS), but glial cells also interact closely with other glial cells. As these cells mature, they undergo a phenomenon known as glial tiling, where they grow to abut one another, often without invading each other’s boundaries. Glial tiling occurs throughout the animal kingdom, from fruit flies to humans; however, not much is known about the glial-glial interactions that lead to and maintain this tiling. Drosophila provide a strong model to investigate glial-glial tiling, where tiling occurs both among individual glial cells of the same subtype, as well as between those of different subtypes. Furthermore, the spatial segregation of the CNS allows for the unique ability to visualize and manipulate inter-subtype interactions. Previous work in Drosophila has suggested an interaction between cortex glia and astrocytes, where astrocytes cross the normal neuropil-cortex boundary in response to dysfunctional cortex glia. Here, we further explore this interaction by implementing an automated pipeline to more fully characterize this astrocyte-cortex glial relationship. By quantifying and correlating the extent of cortex glial dysfunction and aberrant astrocyte infiltration using automated analysis, we maximize the size of the quantified dataset to reveal subtle patterns in astrocyte-cortex glial interactions. We provide a guide for creating and validating a fully-automated image analysis pipeline for exploring these interactions, and implement this pipeline to describe a significant correlation between cortex glial dysfunction and aberrant astrocyte infiltration, as well as demonstrate variations in their relationship across different regions of the CNS.
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Affiliation(s)
- Gabriela Salazar
- Department of Biology, The University of Vermont, Burlington, VT, United States.,Vermont Complex Systems Center, The University of Vermont, Burlington, VT, United States
| | - Grace Ross
- Department of Biology, The University of Vermont, Burlington, VT, United States
| | - Ariana E Maserejian
- Department of Biology, The University of Vermont, Burlington, VT, United States
| | - Jaeda Coutinho-Budd
- Department of Biology, The University of Vermont, Burlington, VT, United States
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25
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Bajar BT, Phi NT, Randhawa H, Akin O. Developmental neural activity requires neuron-astrocyte interactions. Dev Neurobiol 2022; 82:235-244. [PMID: 35225404 PMCID: PMC9018619 DOI: 10.1002/dneu.22870] [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: 05/19/2021] [Revised: 12/06/2021] [Accepted: 01/12/2022] [Indexed: 11/10/2022]
Abstract
Developmental neural activity is a common feature of neural circuit assembly. Although glia have established roles in synapse development, the contribution of neuron-glia interactions to developmental activity remains largely unexplored. Here we show that astrocytes are necessary for developmental activity during synaptogenesis in Drosophila. Using wide-field epifluorescence and two-photon imaging, we show that the glia of the central nervous system participate in developmental activity with type-specific patterns of intracellular calcium dynamics. Genetic ablation of astrocytes, but not of cortex or ensheathing glia, leads to severe attenuation of neuronal activity. Similarly, inhibition of neuronal activity results in the loss of astrocyte calcium dynamics. By altering these dynamics, we show that astrocytic calcium cycles can influence neuronal activity but are not necessary per se. Taken together, our results indicate that, in addition to their recognized role in the structural maturation of synapses, astrocytes are also necessary for the function of synapses during development.
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Affiliation(s)
- Bryce T. Bajar
- Department of Biological Chemistry, Medical Scientist Training Program, Neuroscience Interdepartmental Program, David Geffen School of Medicine at UCLA, Los Angeles, CA, 90095
| | - Nguyen T. Phi
- Department of Neurobiology, David Geffen School of Medicine at UCLA, Los Angeles, CA, 90095
| | - Harpreet Randhawa
- Department of Neurobiology, David Geffen School of Medicine at UCLA, Los Angeles, CA, 90095
| | - Orkun Akin
- Department of Neurobiology, David Geffen School of Medicine at UCLA, Los Angeles, CA, 90095
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26
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Arkov AL. Looking at the Pretty "Phase" of Membraneless Organelles: A View From Drosophila Glia. Front Cell Dev Biol 2022; 10:801953. [PMID: 35198559 PMCID: PMC8859445 DOI: 10.3389/fcell.2022.801953] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2021] [Accepted: 01/19/2022] [Indexed: 11/13/2022] Open
Abstract
Membraneless granules assemble in different cell types and cellular loci and are the focus of intense research due to their fundamental importance for cellular organization. These dynamic organelles are commonly assembled from RNA and protein components and exhibit soft matter characteristics of molecular condensates currently characterized with biophysical approaches and super-resolution microscopy imaging. In addition, research on the molecular mechanisms of the RNA-protein granules assembly provided insights into the formation of abnormal granules and molecular aggregates, which takes place during many neurodegenerative disorders including Parkinson's diseases (PD), Alzheimer's disease (AD), amyotrophic lateral sclerosis (ALS), and frontotemporal dementia (FTD). While these disorders are associated with formation of abnormal granules, membraneless organelles are normally assembled in neurons and contribute to translational control and affect stability of neuronal RNAs. More recently, a new subtype of membraneless granules was identified in Drosophila glia (glial granules). Interestingly, glial granules were found to contain proteins which are the principal components of the membraneless granules in germ cells (germ granules), indicating some similarity in the functional assembly of these structures in glia and germline. This mini review highlights recent research on glial granules in the context of other membraneless organelles, including their assembly mechanisms and potential functions in the nervous system.
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Affiliation(s)
- Alexey L Arkov
- Department of Biological Sciences, Murray State University, Murray, KY, United States
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27
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Pogodalla N, Winkler B, Klämbt C. Glial Tiling in the Insect Nervous System. Front Cell Neurosci 2022; 16:825695. [PMID: 35250488 PMCID: PMC8891220 DOI: 10.3389/fncel.2022.825695] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2021] [Accepted: 01/06/2022] [Indexed: 11/30/2022] Open
Abstract
The Drosophila nervous system comprises a small number of well characterized glial cell classes. The outer surface of the central nervous system (CNS) is protected by a glial derived blood-brain barrier generated by perineurial and subperineurial glia. All neural stem cells and all neurons are engulfed by cortex glial cells. The inner neuropil region, that harbors all synapses and dendrites, is covered by ensheathing glia and infiltrated by astrocyte-like glial cells. All these glial cells show a tiled organization with an often remarkable plasticity where glial cells of one cell type invade the territory of the neighboring glial cell type upon its ablation. Here, we summarize the different glial tiling patterns and based on the different modes of cell-cell contacts we hypothesize that different molecular mechanisms underlie tiling of the different glial cell types.
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28
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Yildirim K, Winkler B, Pogodalla N, Mackensen S, Baldenius M, Garcia L, Naffin E, Rodrigues S, Klämbt C. Redundant functions of the SLC5A transporters Rumpel, Bumpel, and Kumpel in ensheathing glial cells. Biol Open 2021; 11:274028. [PMID: 34897385 PMCID: PMC8790523 DOI: 10.1242/bio.059128] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2021] [Accepted: 11/26/2021] [Indexed: 11/20/2022] Open
Abstract
Neuronal processing is energy demanding, and relies on sugar metabolism. To nurture the Drosophila nervous system, the blood-brain barrier forming glial cells take up trehalose from the hemolymph and then distribute the metabolic products further to all neurons. This function is provided by glucose and lactate transporters of the solute carrier (SLC) 5A family. Here we identified three SLC5A genes that are specifically expressed in overlapping sets of CNS glial cells, rumpel, bumpel and kumpel. We generated mutants in all genes and all mutants are viable and fertile, lacking discernible phenotypes. Loss of rumpel causes subtle locomotor phenotypes and flies display increased daytime sleep. In addition, in bumpel kumpel double mutants, and to an even greater extent in rumpel bumpel kumpel triple mutants, oogenesis is disrupted at the onset of the vitollegenic phase. This indicates a partially redundant functions between these genes. Rescue experiments exploring this effect indicate that oogenesis can be affected by CNS glial cells. Moreover, expression of heterologous mammalian SLC5A transporters, with known transport properties, suggest that Bumpel and/or Kumpel transport glucose or lactate. Overall, our results imply a redundancy in SLC5A nutrient sensing functions in Drosophila glial cells, affecting ovarian development and behavior.
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Affiliation(s)
- Kerem Yildirim
- Institute for Neuro- and Behavioral Biology, University of Münster, Badestr. 9, 48149 Münster, Germany.,Centre for Organismal Studies (COS) Heidelberg, University of Heidelberg, Im Neuenheimer Feld 230, 9120 Heidelberg, Germany
| | - Bente Winkler
- Institute for Neuro- and Behavioral Biology, University of Münster, Badestr. 9, 48149 Münster, Germany
| | - Nicole Pogodalla
- Institute for Neuro- and Behavioral Biology, University of Münster, Badestr. 9, 48149 Münster, Germany
| | - Steffi Mackensen
- Institute for Neuro- and Behavioral Biology, University of Münster, Badestr. 9, 48149 Münster, Germany
| | - Marie Baldenius
- Institute for Neuro- and Behavioral Biology, University of Münster, Badestr. 9, 48149 Münster, Germany
| | - Luis Garcia
- Institute for Neuro- and Behavioral Biology, University of Münster, Badestr. 9, 48149 Münster, Germany
| | - Elke Naffin
- Institute for Neuro- and Behavioral Biology, University of Münster, Badestr. 9, 48149 Münster, Germany
| | - Silke Rodrigues
- Institute for Neuro- and Behavioral Biology, University of Münster, Badestr. 9, 48149 Münster, Germany
| | - Christian Klämbt
- Institute for Neuro- and Behavioral Biology, University of Münster, Badestr. 9, 48149 Münster, Germany
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29
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Drosophila ß Heavy-Spectrin is required in polarized ensheathing glia that form a diffusion-barrier around the neuropil. Nat Commun 2021; 12:6357. [PMID: 34737284 PMCID: PMC8569210 DOI: 10.1038/s41467-021-26462-x] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2020] [Accepted: 10/06/2021] [Indexed: 01/03/2023] Open
Abstract
In 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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30
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Glial glucose fuels the neuronal pentose phosphate pathway for long-term memory. Cell Rep 2021; 36:109620. [PMID: 34433052 PMCID: PMC8411112 DOI: 10.1016/j.celrep.2021.109620] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2020] [Revised: 07/22/2021] [Accepted: 08/05/2021] [Indexed: 01/10/2023] Open
Abstract
Brain function relies almost solely on glucose as an energy substrate. The main model of brain metabolism proposes that glucose is taken up and converted into lactate by astrocytes to fuel the energy-demanding neuronal activity underlying plasticity and memory. Whether direct neuronal glucose uptake is required for memory formation remains elusive. We uncover, in Drosophila, a mechanism of glucose shuttling to neurons from cortex glia, an exclusively perisomatic glial subtype, upon formation of olfactory long-term memory (LTM). In vivo imaging reveals that, downstream of cholinergic activation of cortex glia, autocrine insulin signaling increases glucose concentration in glia. Glucose is then transferred from glia to the neuronal somata in the olfactory memory center to fuel the pentose phosphate pathway and allow LTM formation. In contrast, our results indicate that the increase in neuronal glucose metabolism, although crucial for LTM formation, is not routed to glycolysis. Neuronal glucose metabolism is increased upon long-term memory formation Glial cells shuttle glucose to neurons following insulin signaling activation Glucose fuels the neuronal pentose phosphate pathway
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31
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Dong Q, Zavortink M, Froldi F, Golenkina S, Lam T, Cheng LY. Glial Hedgehog signalling and lipid metabolism regulate neural stem cell proliferation in Drosophila. EMBO Rep 2021; 22:e52130. [PMID: 33751817 DOI: 10.15252/embr.202052130] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2020] [Revised: 02/11/2021] [Accepted: 02/12/2021] [Indexed: 01/07/2023] Open
Abstract
The final size and function of the adult central nervous system (CNS) are determined by neuronal lineages generated by neural stem cells (NSCs) in the developing brain. In Drosophila, NSCs called neuroblasts (NBs) reside within a specialised microenvironment called the glial niche. Here, we explore non-autonomous glial regulation of NB proliferation. We show that lipid droplets (LDs) which reside within the glial niche are closely associated with the signalling molecule Hedgehog (Hh). Under physiological conditions, cortex glial Hh is autonomously required to sustain niche chamber formation. Upon FGF-mediated cortex glial overgrowth, glial Hh non-autonomously activates Hh signalling in the NBs, which in turn disrupts NB cell cycle progression and its ability to produce neurons. Glial Hh's ability to signal to NB is further modulated by lipid storage regulator lipid storage droplet-2 (Lsd-2) and de novo lipogenesis gene fatty acid synthase 1 (Fasn1). Together, our data suggest that glial-derived Hh modified by lipid metabolism mechanisms can affect the neighbouring NB's ability to proliferate and produce neurons.
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Affiliation(s)
- Qian Dong
- Peter MacCallum Cancer Centre, Parkville, Vic., Australia.,Sir Peter MacCallum Department of Oncology, University of Melbourne, Parkville, Vic., Australia
| | - Michael Zavortink
- Peter MacCallum Cancer Centre, Parkville, Vic., Australia.,Sir Peter MacCallum Department of Oncology, University of Melbourne, Parkville, Vic., Australia
| | - Francesca Froldi
- Peter MacCallum Cancer Centre, Parkville, Vic., Australia.,Sir Peter MacCallum Department of Oncology, University of Melbourne, Parkville, Vic., Australia
| | - Sofya Golenkina
- Peter MacCallum Cancer Centre, Parkville, Vic., Australia.,Sir Peter MacCallum Department of Oncology, University of Melbourne, Parkville, Vic., Australia
| | - Tammy Lam
- Peter MacCallum Cancer Centre, Parkville, Vic., Australia.,Sir Peter MacCallum Department of Oncology, University of Melbourne, Parkville, Vic., Australia
| | - Louise Y Cheng
- Peter MacCallum Cancer Centre, Parkville, Vic., Australia.,Sir Peter MacCallum Department of Oncology, University of Melbourne, Parkville, Vic., Australia.,The Department of Anatomy and Neuroscience, University of Melbourne, Parkville, Vic., Australia
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32
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Morpho-Functional Consequences of Swiss Cheese Knockdown in Glia of Drosophila melanogaster. Cells 2021; 10:cells10030529. [PMID: 33801404 PMCID: PMC7998100 DOI: 10.3390/cells10030529] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2021] [Revised: 02/18/2021] [Accepted: 02/24/2021] [Indexed: 01/15/2023] Open
Abstract
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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33
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Lago-Baldaia I, Fernandes VM, Ackerman SD. More Than Mortar: Glia as Architects of Nervous System Development and Disease. Front Cell Dev Biol 2020; 8:611269. [PMID: 33381506 PMCID: PMC7767919 DOI: 10.3389/fcell.2020.611269] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2020] [Accepted: 11/17/2020] [Indexed: 12/12/2022] Open
Abstract
Glial cells are an essential component of the nervous system of vertebrates and invertebrates. In the human brain, glia are as numerous as neurons, yet the importance of glia to nearly every aspect of nervous system development has only been expounded over the last several decades. Glia are now known to regulate neural specification, synaptogenesis, synapse function, and even broad circuit function. Given their ubiquity, it is not surprising that the contribution of glia to neuronal disease pathogenesis is a growing area of research. In this review, we will summarize the accumulated evidence of glial participation in several distinct phases of nervous system development and organization-neural specification, circuit wiring, and circuit function. Finally, we will highlight how these early developmental roles of glia contribute to nervous system dysfunction in neurodevelopmental and neurodegenerative disorders.
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Affiliation(s)
- Inês Lago-Baldaia
- Department of Cell and Developmental Biology, University College London, London, United Kingdom
| | - Vilaiwan M. Fernandes
- Department of Cell and Developmental Biology, University College London, London, United Kingdom
| | - Sarah D. Ackerman
- Institute of Neuroscience, Howard Hughes Medical Institute, University of Oregon, Eugene, OR, United States
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34
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Luan H, Diao F, Scott RL, White BH. The Drosophila Split Gal4 System for Neural Circuit Mapping. Front Neural Circuits 2020; 14:603397. [PMID: 33240047 PMCID: PMC7680822 DOI: 10.3389/fncir.2020.603397] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2020] [Accepted: 10/06/2020] [Indexed: 12/22/2022] Open
Abstract
The diversity and dense interconnectivity of cells in the nervous system present a huge challenge to understanding how brains work. Recent progress toward such understanding, however, has been fuelled by the development of techniques for selectively monitoring and manipulating the function of distinct cell types-and even individual neurons-in the brains of living animals. These sophisticated techniques are fundamentally genetic and have found their greatest application in genetic model organisms, such as the fruit fly Drosophila melanogaster. Drosophila combines genetic tractability with a compact, but cell-type rich, nervous system and has been the incubator for a variety of methods of neuronal targeting. One such method, called Split Gal4, is playing an increasingly important role in mapping neural circuits in the fly. In conjunction with functional perturbations and behavioral screens, Split Gal4 has been used to characterize circuits governing such activities as grooming, aggression, and mating. It has also been leveraged to comprehensively map and functionally characterize cells composing important brain regions, such as the central complex, lateral horn, and the mushroom body-the latter being the insect seat of learning and memory. With connectomics data emerging for both the larval and adult brains of Drosophila, Split Gal4 is also poised to play an important role in characterizing neurons of interest based on their connectivity. We summarize the history and current state of the Split Gal4 method and indicate promising areas for further development or future application.
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Affiliation(s)
| | | | | | - Benjamin H. White
- Laboratory of Molecular Biology, National Institute of Mental Health, NIH, Bethesda, MD, United States
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35
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The Fate of Transplanted Olfactory Progenitors Is Conditioned by the Cell Phenotypes of the Receiver Brain Tissue in Cocultures. Int J Mol Sci 2020; 21:ijms21197249. [PMID: 33008128 PMCID: PMC7582579 DOI: 10.3390/ijms21197249] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2020] [Revised: 09/13/2020] [Accepted: 09/25/2020] [Indexed: 02/07/2023] Open
Abstract
Among the numerous candidates for cell therapy of the central nervous system (CNS), olfactory progenitors (OPs) represent an interesting alternative because they are free of ethical concerns, are easy to collect, and allow autologous transplantation. In the present study, we focused on the optimization of neuron production and maturation. It is known that plated OPs respond to various trophic factors, and we also showed that the use of Nerve Growth Factor (NGF) allowed switching from a 60/40 neuron/glia ratio to an 80/20 one. Nevertheless, in order to focus on the integration of OPs in mature neural circuits, we cocultured OPs in primary cultures obtained from the cortex and hippocampus of newborn mice. When dissociated OPs were plated, they differentiated into both glial and neuronal phenotypes, but we obtained a 1.5-fold higher viability in cortex/OP cocultures than in hippocampus/OP ones. The fate of OPs in cocultures was characterized with different markers such as BrdU, Map-2, and Synapsin, indicating a healthy integration. These results suggest that the integration of transplanted OPs might by affected by trophic factors and the environmental conditions/cell phenotypes of the host tissue. Thus, a model of coculture could provide useful information on key cell events for the use of progenitors in cell therapy.
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36
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Sheng L, Shields EJ, Gospocic J, Glastad KM, Ratchasanmuang P, Berger SL, Raj A, Little S, Bonasio R. Social reprogramming in ants induces longevity-associated glia remodeling. SCIENCE ADVANCES 2020; 6:eaba9869. [PMID: 32875108 PMCID: PMC7438095 DOI: 10.1126/sciadv.aba9869] [Citation(s) in RCA: 40] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/05/2020] [Accepted: 07/09/2020] [Indexed: 05/16/2023]
Abstract
In social insects, workers and queens arise from the same genome but display profound differences in behavior and longevity. In Harpegnathos saltator ants, adult workers can transition to a queen-like state called gamergate, which results in reprogramming of social behavior and life-span extension. Using single-cell RNA sequencing, we compared the distribution of neuronal and glial populations before and after the social transition. We found that the conversion of workers into gamergates resulted in the expansion of neuroprotective ensheathing glia. Brain injury assays revealed that activation of the damage response gene Mmp1 was weaker in old workers, where the relative frequency of ensheathing glia also declined. On the other hand, long-lived gamergates retained a larger fraction of ensheathing glia and the ability to mount a strong Mmp1 response to brain injury into old age. We also observed molecular and cellular changes suggestive of age-associated decline in ensheathing glia in Drosophila.
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Affiliation(s)
- Lihong Sheng
- Epigenetics Institute, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, USA
- Department of Cell and Developmental Biology, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, USA
| | - Emily J. Shields
- Epigenetics Institute, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, USA
- Graduate Group in Genomics and Computational Biology, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, USA
| | - Janko Gospocic
- Epigenetics Institute, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, USA
- Department of Cell and Developmental Biology, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, USA
| | - Karl M. Glastad
- Epigenetics Institute, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, USA
- Department of Cell and Developmental Biology, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, USA
| | - Puttachai Ratchasanmuang
- Department of Cell and Developmental Biology, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, USA
| | - Shelley L. Berger
- Epigenetics Institute, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, USA
- Department of Cell and Developmental Biology, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, USA
- Department of Genetics, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, USA
| | - Arjun Raj
- Epigenetics Institute, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, USA
- Department of Genetics, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, USA
- Department of Bioengineering, University of Pennsylvania, Philadelphia, PA, USA
| | - Shawn Little
- Department of Cell and Developmental Biology, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, USA
| | - Roberto Bonasio
- Epigenetics Institute, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, USA
- Department of Cell and Developmental Biology, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, USA
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37
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Kim T, Song B, Lee IS. Drosophila Glia: Models for Human Neurodevelopmental and Neurodegenerative Disorders. Int J Mol Sci 2020; 21:E4859. [PMID: 32660023 PMCID: PMC7402321 DOI: 10.3390/ijms21144859] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2020] [Revised: 06/27/2020] [Accepted: 07/07/2020] [Indexed: 12/12/2022] Open
Abstract
Glial cells are key players in the proper formation and maintenance of the nervous system, thus contributing to neuronal health and disease in humans. However, little is known about the molecular pathways that govern glia-neuron communications in the diseased brain. Drosophila provides a useful in vivo model to explore the conserved molecular details of glial cell biology and their contributions to brain function and disease susceptibility. Herein, we review recent studies that explore glial functions in normal neuronal development, along with Drosophila models that seek to identify the pathological implications of glial defects in the context of various central nervous system disorders.
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Affiliation(s)
| | | | - Im-Soon Lee
- Department of Biological Sciences, Center for CHANS, Konkuk University, Seoul 05029, Korea; (T.K.); (B.S.)
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38
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Bittern J, Pogodalla N, Ohm H, Brüser L, Kottmeier R, Schirmeier S, Klämbt C. Neuron-glia interaction in the Drosophila nervous system. Dev Neurobiol 2020; 81:438-452. [PMID: 32096904 DOI: 10.1002/dneu.22737] [Citation(s) in RCA: 40] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2019] [Revised: 02/11/2020] [Accepted: 02/24/2020] [Indexed: 12/14/2022]
Abstract
Animals are able to move and react in manifold ways to external stimuli. Thus, environmental stimuli need to be detected, information must be processed, and, finally, an output decision must be transmitted to the musculature to get the animal moving. All these processes depend on the nervous system which comprises an intricate neuronal network and many glial cells. Glial cells have an equally important contribution in nervous system function as their neuronal counterpart. Manifold roles are attributed to glia ranging from controlling neuronal cell number and axonal pathfinding to regulation of synapse formation, function, and plasticity. Glial cells metabolically support neurons and contribute to the blood-brain barrier. All of the aforementioned aspects require extensive cell-cell interactions between neurons and glial cells. Not surprisingly, many of these processes are found in all phyla executed by evolutionarily conserved molecules. Here, we review the recent advance in understanding neuron-glia interaction in Drosophila melanogaster to suggest that work in simple model organisms will shed light on the function of mammalian glial cells, too.
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Affiliation(s)
- Jonas Bittern
- Institut für Neuro- und Verhaltensbiologie, Universität Münster, Münster, Germany
| | - Nicole Pogodalla
- Institut für Neuro- und Verhaltensbiologie, Universität Münster, Münster, Germany
| | - Henrike Ohm
- Institut für Neuro- und Verhaltensbiologie, Universität Münster, Münster, Germany
| | - Lena Brüser
- Institut für Neuro- und Verhaltensbiologie, Universität Münster, Münster, Germany
| | - Rita Kottmeier
- Institut für Neuro- und Verhaltensbiologie, Universität Münster, Münster, Germany
| | - Stefanie Schirmeier
- Institut für Neuro- und Verhaltensbiologie, Universität Münster, Münster, Germany
| | - Christian Klämbt
- Institut für Neuro- und Verhaltensbiologie, Universität Münster, Münster, Germany
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39
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Plazaola-Sasieta H, Zhu Q, Gaitán-Peñas H, Rios M, Estévez R, Morey M. Drosophila ClC-a is required in glia of the stem cell niche for proper neurogenesis and wiring of neural circuits. Glia 2019; 67:2374-2398. [PMID: 31479171 PMCID: PMC6851788 DOI: 10.1002/glia.23691] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2019] [Revised: 07/10/2019] [Accepted: 07/15/2019] [Indexed: 01/01/2023]
Abstract
Glial cells form part of the neural stem cell niche and express a wide variety of ion channels; however, the contribution of these channels to nervous system development is poorly understood. We explored the function of the Drosophila ClC‐a chloride channel, since its mammalian ortholog CLCN2 is expressed in glial cells, and defective channel function results in leukodystrophies, which in humans are accompanied by cognitive impairment. We found that ClC‐a was expressed in the niche in cortex glia, which are closely associated with neurogenic tissues. Characterization of loss‐of‐function ClC‐a mutants revealed that these animals had smaller brains and widespread wiring defects. We showed that ClC‐a is required in cortex glia for neurogenesis in neuroepithelia and neuroblasts, and identified defects in a neuroblast lineage that generates guidepost glial cells essential for photoreceptor axon guidance. We propose that glia‐mediated ionic homeostasis could nonautonomously affect neurogenesis, and consequently, the correct assembly of neural circuits.
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Affiliation(s)
- Haritz Plazaola-Sasieta
- Departament de Genètica, Microbiologia i Estadística, Facultat de Biologia, Universitat de Barcelona, Barcelona, Spain
| | - Qi Zhu
- Departament de Genètica, Microbiologia i Estadística, Facultat de Biologia, Universitat de Barcelona, Barcelona, Spain
| | - Héctor Gaitán-Peñas
- Departament de Ciencies Fisiològiques, Genes, Disease and Therapy Program IDIBELL-Institute of Neurosciences, Universitat de Barcelona, L'Hospitalet de Llobregat, Barcelona, Spain.,Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), Instituto de Salud Carlos III, Madrid, Spain
| | - Martín Rios
- Departament de Genètica, Microbiologia i Estadística, Facultat de Biologia, Universitat de Barcelona, Barcelona, Spain
| | - Raúl Estévez
- Departament de Ciencies Fisiològiques, Genes, Disease and Therapy Program IDIBELL-Institute of Neurosciences, Universitat de Barcelona, L'Hospitalet de Llobregat, Barcelona, Spain.,Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), Instituto de Salud Carlos III, Madrid, Spain
| | - Marta Morey
- Departament de Genètica, Microbiologia i Estadística, Facultat de Biologia, Universitat de Barcelona, Barcelona, Spain.,Institut de Biomedicina de la Universitat de Barcelona (IBUB), Programa de Biologia Integrativa, Barcelona, Spain
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40
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Lee KM, Mathies LD, Grotewiel M. Alcohol sedation in adult Drosophila is regulated by Cysteine proteinase-1 in cortex glia. Commun Biol 2019; 2:252. [PMID: 31286069 PMCID: PMC6610072 DOI: 10.1038/s42003-019-0492-5] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2018] [Accepted: 05/30/2019] [Indexed: 02/06/2023] Open
Abstract
Although numerous studies have demonstrated that neuronal mechanisms regulate alcohol-related behaviors, very few have investigated the direct role of glia in behavioral responses to alcohol. The results described here begin to fill this gap in the alcohol behavior and gliobiology fields. Since Drosophila exhibit conserved behavioral responses to alcohol and their CNS glia are similar to mammalian CNS glia, we used Drosophila to begin exploring the role of glia in alcohol behavior. We found that knockdown of Cysteine proteinase-1 (Cp1) in glia increased Drosophila alcohol sedation and that this effect was specific to cortex glia and adulthood. These data implicate Cp1 and cortex glia in alcohol-related behaviors. Cortex glia are functionally homologous to mammalian astrocytes and Cp1 is orthologous to mammalian Cathepsin L. Our studies raise the possibility that cathepsins may influence behavioral responses to alcohol in mammals via roles in astrocytes.
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Affiliation(s)
- Kristen M. Lee
- Neuroscience Graduate Program, Virginia Commonwealth University, Richmond, VA 23298 USA
| | - Laura D. Mathies
- Department of Pharmacology and Toxicology, Virginia Commonwealth University, Richmond, VA 23298 USA
- Virginia Commonwealth University Alcohol Research Center, Virginia Commonwealth University, Richmond, VA 23298 USA
| | - Mike Grotewiel
- Neuroscience Graduate Program, Virginia Commonwealth University, Richmond, VA 23298 USA
- Virginia Commonwealth University Alcohol Research Center, Virginia Commonwealth University, Richmond, VA 23298 USA
- Department of Human and Molecular Genetics, Virginia Commonwealth University, Richmond, VA 23298 USA
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41
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Li XQ, Yu Q, Fang B, Zhang ZL, Ma H. Knockdown of the AIM2 molecule attenuates ischemia-reperfusion-induced spinal neuronal pyroptosis by inhibiting AIM2 inflammasome activation and subsequent release of cleaved caspase-1 and IL-1β. Neuropharmacology 2019; 160:107661. [PMID: 31181224 DOI: 10.1016/j.neuropharm.2019.05.038] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2019] [Revised: 05/23/2019] [Accepted: 05/31/2019] [Indexed: 01/05/2023]
Abstract
Ischemia-reperfusion (IR) injury induces activation of several inflammasomes that widely affect neuroinflammation and, subsequently, neuronal viability. The absent in melanoma 2 (AIM2) inflammasome is highly expressed in neurons after traumatic injury. This study was performed to investigate whether the AIM2 molecule acts as an initiator to trigger AIM2 inflammasome activation and regulate neuronal pyroptosis in a mouse IR model. The early motor dysfunction that occurred within the first 8 h post-IR injury was closely associated with a massive increase in dsDNA in serum and cerebrospinal fluid (CSF) at the same observed timepoints. However, the subsequent persistent dysfunction was consistent with the continuously increasing protein levels of apoptosis-associated speck-like protein containing a caspase-recruitment domain (ASC), cleaved caspase-1 and IL-1β with time. Upregulated AIM2 immunoreactivity was primarily visualized in neurons. The si-AIM2 treatment in vivo preserved part of motor function, accompanied by decreased protein levels of AIM2, ASC, cleaved caspase-1 and IL-1β. In vitro, the direct interactions between the AIM2 molecule and caspase-1 were demonstrated by immunofluorescence staining and coimmunoprecipitation. In this context, both si-AIM2 and Ac-YVAD-CMK treatments effectively maintained neuronal viability, as demonstrated by the decreased percentage of cells with pyroptosis and release of lactate dehydrogenase (LDH), accompanied by weak immunoreactivity and a decreased number of AIM2-caspase-1 positive neurons. By contrast, poly(dA-dT) treatment exacerbated neuronal pyroptosis by reversing the above-mentioned effects. However, no significant differences were observed after si-Con treatment. These results suggest AIM2 molecule played an important role in initiating AIM2 inflammasome activation through IR-induced release of ectopic dsDNA.
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Affiliation(s)
- Xiao-Qian Li
- Department of Anesthesiology, First Affiliated Hospital, China Medical University, Shenyang, 110001, Liaoning, China.
| | - Qian Yu
- Department of Thoracic Surgery, Fourth Affiliated Hospital, China Medical University, Shenyang, 110032, Liaoning, China.
| | - Bo Fang
- Department of Anesthesiology, First Affiliated Hospital, China Medical University, Shenyang, 110001, Liaoning, China.
| | - Zai-Li Zhang
- Department of Anesthesiology, First Affiliated Hospital, China Medical University, Shenyang, 110001, Liaoning, China.
| | - Hong Ma
- Department of Anesthesiology, First Affiliated Hospital, China Medical University, Shenyang, 110001, Liaoning, China.
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42
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Weiss S, Melom JE, Ormerod KG, Zhang YV, Littleton JT. Glial Ca 2+signaling links endocytosis to K + buffering around neuronal somas to regulate excitability. eLife 2019; 8:44186. [PMID: 31025939 PMCID: PMC6510531 DOI: 10.7554/elife.44186] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2018] [Accepted: 04/25/2019] [Indexed: 12/30/2022] Open
Abstract
Glial-neuronal signaling at synapses is widely studied, but how glia interact with neuronal somas to regulate their activity is unclear. Drosophila cortex glia are restricted to brain regions devoid of synapses, providing an opportunity to characterize interactions with neuronal somas. Mutations in the cortex glial NCKXzydeco elevate basal Ca2+, predisposing animals to seizure-like behavior. To determine how cortex glial Ca2+ signaling controls neuronal excitability, we performed an in vivo modifier screen of the NCKXzydeco seizure phenotype. We show that elevation of glial Ca2+ causes hyperactivation of calcineurin-dependent endocytosis and accumulation of early endosomes. Knockdown of sandman, a K2P channel, recapitulates NCKXzydeco seizures. Indeed, sandman expression on cortex glial membranes is substantially reduced in NCKXzydeco mutants, indicating enhanced internalization of sandman predisposes animals to seizures. These data provide an unexpected link between glial Ca2+ signaling and the well-known role of glia in K+ buffering as a key mechanism for regulating neuronal excitability.
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Affiliation(s)
- Shirley Weiss
- The Picower Institute for Learning and Memory, Massachusetts Institute of Technology, Cambridge, United States.,Department of Biology, Massachusetts Institute of Technology, Cambridge, United States.,Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, United States
| | - Jan E Melom
- The Picower Institute for Learning and Memory, Massachusetts Institute of Technology, Cambridge, United States.,Department of Biology, Massachusetts Institute of Technology, Cambridge, United States.,Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, United States
| | - Kiel G Ormerod
- The Picower Institute for Learning and Memory, Massachusetts Institute of Technology, Cambridge, United States.,Department of Biology, Massachusetts Institute of Technology, Cambridge, United States.,Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, United States
| | - Yao V Zhang
- The Picower Institute for Learning and Memory, Massachusetts Institute of Technology, Cambridge, United States.,Department of Biology, Massachusetts Institute of Technology, Cambridge, United States.,Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, United States
| | - J Troy Littleton
- Department of Biology, Massachusetts Institute of Technology, Cambridge, United States
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43
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Glial ensheathment of the somatodendritic compartment regulates sensory neuron structure and activity. Proc Natl Acad Sci U S A 2019; 116:5126-5134. [PMID: 30804200 DOI: 10.1073/pnas.1814456116] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Sensory neurons perceive environmental cues and are important of organismal survival. Peripheral sensory neurons interact intimately with glial cells. While the function of axonal ensheathment by glia is well studied, less is known about the functional significance of glial interaction with the somatodendritic compartment of neurons. Herein, we show that three distinct glia cell types differentially wrap around the axonal and somatodendritic surface of the polymodal dendritic arborization (da) neuron of the Drosophila peripheral nervous system for detection of thermal, mechanical, and light stimuli. We find that glial cell-specific loss of the chromatin modifier gene dATRX in the subperineurial glial layer leads to selective elimination of somatodendritic glial ensheathment, thus allowing us to investigate the function of such ensheathment. We find that somatodendritic glial ensheathment regulates the morphology of the dendritic arbor, as well as the activity of the sensory neuron, in response to sensory stimuli. Additionally, glial ensheathment of the neuronal soma influences dendritic regeneration after injury.
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44
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Green LA, Nebiolo JC, Smith CJ. Microglia exit the CNS in spinal root avulsion. PLoS Biol 2019; 17:e3000159. [PMID: 30794533 PMCID: PMC6402705 DOI: 10.1371/journal.pbio.3000159] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2018] [Revised: 03/06/2019] [Accepted: 02/06/2019] [Indexed: 12/31/2022] Open
Abstract
Microglia are central nervous system (CNS)-resident cells. Their ability to migrate outside of the CNS, however, is not understood. Using time-lapse imaging in an obstetrical brachial plexus injury (OBPI) model, we show that microglia squeeze through the spinal boundary and emigrate to peripheral spinal roots. Although both macrophages and microglia respond, microglia are the debris-clearing cell. Once outside the CNS, microglia re-enter the spinal cord in an altered state. These peripheral nervous system (PNS)-experienced microglia can travel to distal CNS areas from the injury site, including the brain, with debris. This emigration is balanced by two mechanisms—induced emigration via N-methyl-D-aspartate receptor (NMDA) dependence and restriction via contact-dependent cellular repulsion with macrophages. These discoveries open the possibility that microglia can migrate outside of their textbook-defined regions in disease states. Microglia are normally assumed to be confined to the central nervous system (CNS), but this study shows show that after spinal root injury, microglia can exit the CNS to clear debris. Upon re-entry, the emigrated microglia are altered and can travel to distal areas such as the brain. Cells are precisely organized in specific anatomical domains to ensure normal functioning of the nervous system. One such cell type, microglia, is usually considered to be confined to the central nervous system (CNS). Using time-lapse imaging to capture microglia as they migrate, we show that their characteristic CNS-residency can be altered after spinal root injury. After such injury, the microglia exit the spinal root to the periphery, where they clear debris at the injury site and then carry that debris back into the CNS. In addition, microglia that leave the CNS after spinal root injury become distinct from those that remain within the CNS. This emigration event of microglia after injury is driven by two mechanisms—dependence on glutamatergic signaling that induces their emigration to the injury and interactions with macrophages that prevent their ectopic exit from the spinal cord. Together, these discoveries raise the possibility that microglia could override their CNS-residency in certain disease contexts.
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Affiliation(s)
- Lauren A Green
- Department of Biological Sciences, University of Notre Dame, Notre Dame, Indiana, United States of America.,Center for Stem Cells and Regenerative Medicine, University of Notre Dame, Notre Dame, Indiana, United States of America
| | - Julia C Nebiolo
- Department of Biological Sciences, University of Notre Dame, Notre Dame, Indiana, United States of America
| | - Cody J Smith
- Department of Biological Sciences, University of Notre Dame, Notre Dame, Indiana, United States of America.,Center for Stem Cells and Regenerative Medicine, University of Notre Dame, Notre Dame, Indiana, United States of America
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45
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McLaughlin CN, Perry-Richardson JJ, Coutinho-Budd JC, Broihier HT. Dying Neurons Utilize Innate Immune Signaling to Prime Glia for Phagocytosis during Development. Dev Cell 2019; 48:506-522.e6. [PMID: 30745142 DOI: 10.1016/j.devcel.2018.12.019] [Citation(s) in RCA: 39] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2018] [Revised: 11/19/2018] [Accepted: 12/21/2018] [Indexed: 02/06/2023]
Abstract
Glia continuously survey neuronal health during development, providing trophic support to healthy neurons while rapidly engulfing dying ones. These diametrically opposed functions necessitate a foolproof mechanism enabling glia to unambiguously identify those neurons to support versus those to engulf. To ensure specificity, glia are proposed to interact with dying neurons via a series of carefully choreographed steps. However, these crucial interactions are largely obscure. Here we show that dying neurons and glia communicate via Toll-receptor-regulated innate immune signaling. Neuronal apoptosis drives processing and activation of the Toll-6 ligand, Spätzle5. This cue activates a dSARM-mediated Toll-6 transcriptional pathway in glia, which controls the expression of the Draper engulfment receptor. Pathway loss drives early-onset neurodegeneration, underscoring its functional importance. Our results identify an upstream priming signal that prepares glia for phagocytosis. Thus, a core innate immune pathway plays an unprecedented role setting the valence of neuron-glia interactions during development.
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Affiliation(s)
- Colleen N McLaughlin
- Department of Neurosciences, Case Western Reserve University School of Medicine, Cleveland, OH 44106, USA.
| | - Jahci J Perry-Richardson
- Department of Neurosciences, Case Western Reserve University School of Medicine, Cleveland, OH 44106, USA
| | | | - Heather T Broihier
- Department of Neurosciences, Case Western Reserve University School of Medicine, Cleveland, OH 44106, USA.
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46
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Chen AS, Read RD. Drosophila melanogaster as a Model System for Human Glioblastomas. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2019; 1167:207-224. [PMID: 31520357 DOI: 10.1007/978-3-030-23629-8_12] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Glioblastoma multiforme (GBM) is the most common primary malignant adult brain tumor. Genomic amplifications, activating mutations, and overexpression of receptor tyrosine kinases (RTKs) such as EGFR, and genes in core RTK signaling transduction pathways such as PI3K are common in GBM. However, efforts to target these pathways have been largely unsuccessful in the clinic, and the median survival of GBM patients remains poor at 14-15 months. Therefore, to improve patient outcomes, there must be a concerted effort to elucidate the underlying biology involved in GBM tumorigenesis. Drosophila melanogaster has been a highly effective model for furthering our understanding of GBM tumorigenesis due to a number of experimental advantages it has over traditional mouse models. For example, there exists extensive cellular and genetic homology between humans and Drosophila, and 75% of genes associated with human disease have functional fly orthologs. To take advantage of these traits, we developed a Drosophila GBM model with constitutively active variants of EGFR and PI3K that effectively recapitulated key aspects of GBM disease. Researchers have utilized this model in forward genetic screens and have expanded on its functionality to make a number of important discoveries regarding requirements for key components in GBM tumorigenesis, including genes and pathways involved in extracellular matrix signaling, glycolytic metabolism, invasion/migration, stem cell fate and differentiation, and asymmetric cell division. Drosophila will continue to reveal novel biological pathways and mechanisms involved in gliomagenesis, and this knowledge may contribute to the development of effective treatment strategies to improve patient outcomes.
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Affiliation(s)
- Alexander S Chen
- Department of Pharmacology and Chemical Biology, Emory University School of Medicine, Atlanta, GA, USA
| | - Renee D Read
- Department of Pharmacology and Chemical Biology, Emory University School of Medicine, Atlanta, GA, USA. .,Department of Hematology and Medical Oncology, Emory University School of Medicine, Atlanta, GA, USA. .,Winship Cancer Center, Emory University School of Medicine, Atlanta, GA, USA.
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47
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Read RD. Pvr receptor tyrosine kinase signaling promotes post-embryonic morphogenesis, and survival of glia and neural progenitor cells in Drosophila. Development 2018; 145:dev.164285. [PMID: 30327326 DOI: 10.1242/dev.164285] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2018] [Accepted: 10/10/2018] [Indexed: 12/30/2022]
Abstract
Stem cells reside in specialized microenvironments, called niches, that regulate their development and the development of their progeny. However, the development and maintenance of niches are poorly understood. In the Drosophila brain, cortex glial cells provide a niche that promotes self-renewal and proliferation of neural stem cell-like cells (neuroblasts). In the central brain, neuroblasts and their progeny control post-embryonic morphogenesis of cortex glia through PDGF-like ligands, and this PDGFR receptor tyrosine kinase (RTK) signaling in cortex glia is required for expression of DE-cadherin, which sustains neuroblasts. Thus, through an RTK-dependent feed-forward loop, neuroblasts and their glial niche actively maintain each other. When the EGFR RTK is constitutively activated in cortex glia, they overexpress PDGF orthologs to stimulate autocrine PDGFR signaling, which uncouples their growth and survival from neuroblasts, and drives neoplastic glial transformation and elimination of neuroblasts. These results provide fundamental insights into glial development and niche regulation, and show that niche-neural stem cell feed-forward signaling becomes hijacked to drive neural tumorigenesis.
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Affiliation(s)
- Renee D Read
- Department of Pharmacology, Emory University School of Medicine, Atlanta, GA 30322, USA
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48
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Yildirim K, Petri J, Kottmeier R, Klämbt C. Drosophila glia: Few cell types and many conserved functions. Glia 2018; 67:5-26. [DOI: 10.1002/glia.23459] [Citation(s) in RCA: 75] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2018] [Revised: 04/25/2018] [Accepted: 05/04/2018] [Indexed: 12/20/2022]
Affiliation(s)
- Kerem Yildirim
- Institute for Neuro and Behavioral Biology; University of Münster; Badestraße 9, 48149 Münster Germany
| | - Johanna Petri
- Institute for Neuro and Behavioral Biology; University of Münster; Badestraße 9, 48149 Münster Germany
| | - Rita Kottmeier
- Institute for Neuro and Behavioral Biology; University of Münster; Badestraße 9, 48149 Münster Germany
| | - Christian Klämbt
- Institute for Neuro and Behavioral Biology; University of Münster; Badestraße 9, 48149 Münster Germany
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49
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Kunduri G, Turner-Evans D, Konya Y, Izumi Y, Nagashima K, Lockett S, Holthuis J, Bamba T, Acharya U, Acharya JK. Defective cortex glia plasma membrane structure underlies light-induced epilepsy in cpes mutants. Proc Natl Acad Sci U S A 2018; 115:E8919-E8928. [PMID: 30185559 PMCID: PMC6156639 DOI: 10.1073/pnas.1808463115] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Seizures induced by visual stimulation (photosensitive epilepsy; PSE) represent a common type of epilepsy in humans, but the molecular mechanisms and genetic drivers underlying PSE remain unknown, and no good genetic animal models have been identified as yet. Here, we show an animal model of PSE, in Drosophila, owing to defective cortex glia. The cortex glial membranes are severely compromised in ceramide phosphoethanolamine synthase (cpes)-null mutants and fail to encapsulate the neuronal cell bodies in the Drosophila neuronal cortex. Expression of human sphingomyelin synthase 1, which synthesizes the closely related ceramide phosphocholine (sphingomyelin), rescues the cortex glial abnormalities and PSE, underscoring the evolutionarily conserved role of these lipids in glial membranes. Further, we show the compromise in plasma membrane structure that underlies the glial cell membrane collapse in cpes mutants and leads to the PSE phenotype.
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Affiliation(s)
- Govind Kunduri
- Cancer and Developmental Biology Laboratory, National Cancer Institute, Frederick, MD 21702
| | | | - Yutaka Konya
- Department of Metabolomics, Kyushu University, Fukuoka 812-8582, Japan
| | - Yoshihiro Izumi
- Department of Metabolomics, Kyushu University, Fukuoka 812-8582, Japan
| | - Kunio Nagashima
- Electron Microscopy Laboratory, National Cancer Institute, Frederick, MD 21702
| | - Stephen Lockett
- Optical Microscopy and Analysis Laboratory, Frederick National Laboratory for Cancer Research, Frederick, MD 21702
| | - Joost Holthuis
- Molecular Cell Biology Division, University of Osnabrück, 49074 Osnabrück, Germany
| | - Takeshi Bamba
- Department of Metabolomics, Kyushu University, Fukuoka 812-8582, Japan
| | - Usha Acharya
- Department of Molecular, Cell and Cancer Biology, University of Massachusetts Medical School, Worcester, MA 01605
| | - Jairaj K Acharya
- Cancer and Developmental Biology Laboratory, National Cancer Institute, Frederick, MD 21702;
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50
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Li XQ, Yu Q, Chen FS, Tan WF, Zhang ZL, Ma H. Inhibiting aberrant p53-PUMA feedback loop activation attenuates ischaemia reperfusion-induced neuroapoptosis and neuroinflammation in rats by downregulating caspase 3 and the NF-κB cytokine pathway. J Neuroinflammation 2018; 15:250. [PMID: 30172256 PMCID: PMC6119253 DOI: 10.1186/s12974-018-1271-9] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2018] [Accepted: 08/05/2018] [Indexed: 12/31/2022] Open
Abstract
Background Ischaemia reperfusion (IR) induces multiple pathophysiological changes. In addition to its classical role in regulating tumourigenesis, the feedback loop formed by p53 and its driven target p53-upregulated modulator of apoptosis (PUMA) was recently demonstrated to be the common node tightly controlling various cellular responses during myocardial IR. However, the roles of the p53-PUMA feedback loop in the spinal cord remain unclear. This study aimed to elucidate the roles of p53-PUMA feedback interactions in the spinal cord after IR, specifically investigating their regulation of caspase 3-mediated apoptosis and nuclear factor (NF)-κB-mediated cytokine release. Methods SD rats subjected to 12 min of aortic arch occlusion served as IR models. Neurological assessment as well as p53 and PUMA mRNA and protein expression analyses were performed at 12-h intervals during a 48-h reperfusion period. The cellular distributions of p53 and PUMA were determined via double immunofluorescence staining. The effects of the p53-PUMA feedback loop on modulating hind-limb function; the number of TUNEL-positive cells; and protein levels of caspase 3, NF-κB and cytokines interleukin (IL)-1β and tumour necrosis factor (TNF)-α, were evaluated by intrathecal treatment with PUMA-specific or scramble siRNA and pifithrin (PFT)-α. Blood-spinal cord barrier (BSCB) breakdown was examined by Evans blue (EB) extravasation and water content analyses. Results IR induced significant behavioural deficits as demonstrated by deceased Tarlov scores, which displayed trends opposite those of PUMA and p53 protein and mRNA expression. Upregulated PUMA and p53 fluorescent labels were widely distributed in neurons, astrocytes and microglia. Injecting si-PUMA and PFT-α exerted significant anti-apoptosis effects as shown by the reduced number of TUNEL-positive cells, nuclear abnormalities and cleaved caspase 3 levels at 48 h post-IR. Additionally, p53 colocalized with NF-κB within the cell. Similarly, injecting si-PUMA and PFT-α exerted anti-inflammatory effects as shown by the decreased NF-κB translocation and release of IL-1β and TNF-α. Additionally, injecting si-PUMA and PFT-α preserved the BSCB integrity as determined by decreased EB extravasation and spinal water content. However, injecting si-Con did not induce any of the abovementioned effects. Conclusions Inhibition of aberrant p53-PUMA feedback loop activation by intrathecal treatment with si-PUMA and PFT-α prevented IR-induced neuroapoptosis, inflammatory responses and BSCB breakdown by inactivating caspase 3-mediated apoptosis and NF-κB-mediated cytokine release.
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Affiliation(s)
- Xiao-Qian Li
- Department of Anesthesiology, First Affiliated Hospital, China Medical University, Shenyang, 110001, Liaoning, China
| | - Qian Yu
- Department of Thoracic Surgery, Fourth Affiliated Hospital, China Medical University, Shenyang, 110032, Liaoning, China
| | - Feng-Shou Chen
- Department of Anesthesiology, First Affiliated Hospital, China Medical University, Shenyang, 110001, Liaoning, China
| | - Wen-Fei Tan
- Department of Anesthesiology, First Affiliated Hospital, China Medical University, Shenyang, 110001, Liaoning, China
| | - Zai-Li Zhang
- Department of Anesthesiology, First Affiliated Hospital, China Medical University, Shenyang, 110001, Liaoning, China
| | - Hong Ma
- Department of Anesthesiology, First Affiliated Hospital, China Medical University, Shenyang, 110001, Liaoning, China.
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