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Zhang X, Sun D, Wong K, Salkini A, Najafi H, Kim WJ. The astrocyte-enriched gene deathstar plays a crucial role in the development, locomotion, and lifespan of D. melanogaster. Fly (Austin) 2024; 18:2368336. [PMID: 38884422 PMCID: PMC11185185 DOI: 10.1080/19336934.2024.2368336] [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: 10/22/2023] [Accepted: 06/11/2024] [Indexed: 06/18/2024] Open
Abstract
The Drosophila melanogaster brain is a complex organ with various cell types, orchestrating the development, physiology, and behaviors of the fly. While each cell type in Drosophila brain is known to express a unique gene set, their complete genetic profile is still unknown. Advances in the RNA sequencing techniques at single-cell resolution facilitate identifying novel cell type markers and/or re-examining the specificity of the available ones. In this study, exploiting a single-cell RNA sequencing data of Drosophila optic lobe, we categorized the cells based on their expression pattern for known markers, then the genes with enriched expression in astrocytes were identified. CG11000 was identified as a gene with a comparable expression profile to the Eaat1 gene, an astrocyte marker, in every individual cell inside the Drosophila optic lobe and midbrain, as well as in the entire Drosophila brain throughout its development. Consistent with our bioinformatics data, immunostaining of the brains dissected from transgenic adult flies showed co-expression of CG11000 with Eaat1 in a set of single cells corresponding to the astrocytes in the Drosophila brain. Physiologically, inhibiting CG11000 through RNA interference disrupted the normal development of male D. melanogaster, while having no impact on females. Expression suppression of CG11000 in adult flies led to decreased locomotion activity and also shortened lifespan specifically in astrocytes, indicating the gene's significance in astrocytes. We designated this gene as 'deathstar' due to its crucial role in maintaining the star-like shape of glial cells, astrocytes, throughout their development into adult stage.
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Affiliation(s)
- Xiaoli Zhang
- The HIT Center for Life Sciences, Harbin Institute of Technology, Harbin, China
| | - Dongyu Sun
- The HIT Center for Life Sciences, Harbin Institute of Technology, Harbin, China
| | - Kyle Wong
- Department of Cellular and Molecular Medicine, Faculty of Medicine, University of Ottawa, Ottawa, ON, Canada
| | - Ammar Salkini
- Department of Cellular and Molecular Medicine, Faculty of Medicine, University of Ottawa, Ottawa, ON, Canada
| | - Hadi Najafi
- Department of Cellular and Molecular Medicine, Faculty of Medicine, University of Ottawa, Ottawa, ON, Canada
- Department of Molecular, Cell and Cancer Biology, University of Massachusetts Chan Medical School, Worcester, MA, USA
| | - Woo Jae Kim
- The HIT Center for Life Sciences, Harbin Institute of Technology, Harbin, China
- Department of Cellular and Molecular Medicine, Faculty of Medicine, University of Ottawa, Ottawa, ON, Canada
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2
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Beachum AN, Salazar G, Nachbar A, Krause K, Klose H, Meyer K, Maserejian A, Ross G, Boyd H, Weigel T, Ambaye L, Miller H, Coutinho-Budd J. Glia multitask to compensate for neighboring glial cell dysfunction. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.09.06.611719. [PMID: 39314422 PMCID: PMC11418964 DOI: 10.1101/2024.09.06.611719] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 09/25/2024]
Abstract
As glia mature, they undergo glial tiling to abut one another without invading each other's boundaries. Upon the loss of the secreted neurotrophin Spätzle3 (Spz3), Drosophila cortex glia transform morphologically and lose their intricate interactions with neurons and surrounding glial subtypes. Here, we reveal that all neighboring glial cell types (astrocytes, ensheathing glia, and subperineurial glia) react by extending processes into the previous cortex glial territory to compensate for lost cortex glial function and reduce the buildup of neuronal debris. However, the loss of Spz3 alone is not sufficient for glia to cross their natural borders, as blocking CNS growth via nutrient-restriction blocks the aberrant infiltration induced by the loss of Spz3. Surprisingly, even when these neighboring glia divert their cellular resources beyond their typical borders to take on new compensatory roles, they are able to multitask to continue to preserve their own normal functions to maintain CNS homeostasis.
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Affiliation(s)
- Allison N Beachum
- Department of Neuroscience, University of Virginia, Charlottesville, VA 22903
| | - Gabriela Salazar
- Department of Neuroscience, University of Virginia, Charlottesville, VA 22903
| | - Amelia Nachbar
- Department of Neuroscience, University of Virginia, Charlottesville, VA 22903
| | - Kevin Krause
- Department of Neuroscience, University of Virginia, Charlottesville, VA 22903
| | - Hannah Klose
- Department of Neuroscience, University of Virginia, Charlottesville, VA 22903
| | - Kate Meyer
- Department of Neuroscience, University of Virginia, Charlottesville, VA 22903
| | | | - Grace Ross
- Department of Biology, University of Vermont, Burlington, VT 05405
| | - Hannah Boyd
- Department of Biology, University of Vermont, Burlington, VT 05405
| | - Thaddeus Weigel
- Department of Neuroscience, University of Virginia, Charlottesville, VA 22903
| | - Lydia Ambaye
- Department of Biology, University of Vermont, Burlington, VT 05405
| | - Hayes Miller
- Department of Neuroscience, University of Virginia, Charlottesville, VA 22903
| | - Jaeda Coutinho-Budd
- Department of Neuroscience, University of Virginia, Charlottesville, VA 22903
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3
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Oka M, Nakajima S, Suzuki E, Yamamoto S, Ando K. Glucose uptake in pigment glia suppresses tau-induced inflammation and photoreceptor degeneration in Drosophila. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.08.14.607919. [PMID: 39229232 PMCID: PMC11370381 DOI: 10.1101/2024.08.14.607919] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/05/2024]
Abstract
Brain inflammation contributes to the pathogenesis of neurodegenerative diseases such as Alzheimer's disease (AD). Glucose hypometabolism and glial activation are pathological features seen in AD brains; however, the connection between the two is not fully understood. Using a Drosophila model of AD, we identified that glucose metabolism in glia plays a critical role in neuroinflammation under disease conditions. Expression of human tau in the retinal cells, including photoreceptor neurons and pigment glia, causes photoreceptor degeneration accompanied by inclusion formation and swelling of lamina glial cells. We found that inclusions are formed by glial phagocytosis, and swelling of the laminal cortex correlates with the expression of antimicrobial peptides (AMPs). Co-expression of human glucose transporter 3 ( GLUT3 ) with tau in the retina does not affect tau levels but suppresses these inflammatory responses and photoreceptor degeneration. We also found that expression of GLUT3 , specifically in the pigment glia, is sufficient to suppress inflammatory phenotypes and mitigate photoreceptor degeneration in the tau-expressing retina. Our results suggest that glial glucose metabolism contributes to inflammatory responses and neurodegeneration in tauopathy. Highlights Tau expression in the fly retina induces glial activationPigment glial cells mediate inflammatory phenotypes in the degenerating retinaEnhanced glucose uptake in the pigment glia suppresses inflammation and photoreceptor neurodegeneration caused by tau expression.
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4
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Ichinose T, Kondo S, Kanno M, Shichino Y, Mito M, Iwasaki S, Tanimoto H. Translational regulation enhances distinction of cell types in the nervous system. eLife 2024; 12:RP90713. [PMID: 39010741 PMCID: PMC11251722 DOI: 10.7554/elife.90713] [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] [Indexed: 07/17/2024] Open
Abstract
Multicellular organisms are composed of specialized cell types with distinct proteomes. While recent advances in single-cell transcriptome analyses have revealed differential expression of mRNAs, cellular diversity in translational profiles remains underinvestigated. By performing RNA-seq and Ribo-seq in genetically defined cells in the Drosophila brain, we here revealed substantial post-transcriptional regulations that augment the cell-type distinctions at the level of protein expression. Specifically, we found that translational efficiency of proteins fundamental to neuronal functions, such as ion channels and neurotransmitter receptors, was maintained low in glia, leading to their preferential translation in neurons. Notably, distribution of ribosome footprints on these mRNAs exhibited a remarkable bias toward the 5' leaders in glia. Using transgenic reporter strains, we provide evidence that the small upstream open-reading frames in the 5' leader confer selective translational suppression in glia. Overall, these findings underscore the profound impact of translational regulation in shaping the proteomics for cell-type distinction and provide new insights into the molecular mechanisms driving cell-type diversity.
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Grants
- 21K06369 Ministry of Education, Culture, Sports, Science and Technology
- 21H05713 Ministry of Education, Culture, Sports, Science and Technology
- JP20H05784 Ministry of Education, Culture, Sports, Science and Technology
- JP21K15023 Ministry of Education, Culture, Sports, Science and Technology
- 22H05481 Ministry of Education, Culture, Sports, Science and Technology
- 22KK0106 Ministry of Education, Culture, Sports, Science and Technology
- 20H00519 Ministry of Education, Culture, Sports, Science and Technology
- JP20gm1410001 Japan Agency for Medical Research and Development
- Biology of Intracellular Environments RIKEN
- Special Postdoctoral Researchers RIKEN
- Incentive Research Projects RIKEN
- Takeda Science Foundation
- Tohoku University Research Program "Frontier Research in Duo"
- The Uehara Memorial Foundation
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Affiliation(s)
- Toshiharu Ichinose
- Frontier Research Institute for Interdisciplinary Sciences, Tohoku UniversitySendaiJapan
- Graduate School of Life Sciences, Tohoku UniversitySendaiJapan
| | - Shu Kondo
- Faculty of Advanced Engineering, Tokyo University of SciencesTokyoJapan
| | - Mai Kanno
- Frontier Research Institute for Interdisciplinary Sciences, Tohoku UniversitySendaiJapan
- Graduate School of Life Sciences, Tohoku UniversitySendaiJapan
| | - Yuichi Shichino
- RNA Systems Biochemistry Laboratory, RIKEN Cluster for Pioneering Research, WakoSaitamaJapan
| | - Mari Mito
- RNA Systems Biochemistry Laboratory, RIKEN Cluster for Pioneering Research, WakoSaitamaJapan
| | - Shintaro Iwasaki
- RNA Systems Biochemistry Laboratory, RIKEN Cluster for Pioneering Research, WakoSaitamaJapan
- Department of Computational Biology and Medical Sciences, Graduate School of Frontier Sciences, The University of TokyoKashiwaJapan
| | - Hiromu Tanimoto
- Graduate School of Life Sciences, Tohoku UniversitySendaiJapan
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5
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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] [Grants] [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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Affiliation(s)
- Hans C Leier
- Department of Neurosciences, Case Western Reserve University School of Medicine, Cleveland, United States
| | - Alexander J Foden
- Department of Neurosciences, Case Western Reserve University School of Medicine, Cleveland, United States
| | - Darren A Jindal
- Department of Neurosciences, Case Western Reserve University School of Medicine, Cleveland, United States
| | - Abigail J Wilkov
- Department of Neurosciences, Case Western Reserve University School of Medicine, Cleveland, United States
| | | | - Pamela J Vanderzalm
- Department of Biology, John Carroll University, University Heights, United States
| | - Jaeda C Coutinho-Budd
- Department of Neuroscience, University of Virginia School of Medicine, Charlottesville, United States
| | - Masashi Tabuchi
- Department of Neurosciences, Case Western Reserve University School of Medicine, Cleveland, United States
| | - Heather T Broihier
- Department of Neurosciences, Case Western Reserve University School of Medicine, Cleveland, United States
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6
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Fioriti F, Rifflet A, Gomperts Boneca I, Zugasti O, Royet J. Bacterial peptidoglycan serves as a critical modulator of the gut-immune-brain axis in Drosophila. Brain Behav Immun 2024; 119:878-897. [PMID: 38710338 DOI: 10.1016/j.bbi.2024.05.009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/08/2023] [Revised: 04/26/2024] [Accepted: 05/03/2024] [Indexed: 05/08/2024] Open
Abstract
Metabolites and compounds derived from gut-associated bacteria can modulate numerous physiological processes in the host, including immunity and behavior. Using a model of oral bacterial infection, we previously demonstrated that gut-derived peptidoglycan (PGN), an essential constituent of the bacterial cell envelope, influences female fruit fly egg-laying behavior by activating the NF-κB cascade in a subset of brain neurons. These findings underscore PGN as a potential mediator of communication between gut bacteria and the brain in Drosophila, prompting further investigation into its impact on all brain cells. Through high-resolution mass spectrometry, we now show that PGN fragments produced by gut bacteria can rapidly reach the central nervous system. In Addition, by employing a combination of whole-genome transcriptome analyses, comprehensive genetic assays, and reporter gene systems, we reveal that gut bacterial infection triggers a PGN dose-dependent NF-κB immune response in perineurial glia, forming the continuous outer cell layer of the blood-brain barrier. Furthermore, we demonstrate that persistent PGN-dependent NF-κB activation in perineurial glial cells correlates with a reduction in lifespan and early neurological decline. Overall, our findings establish gut-derived PGN as a critical mediator of the gut-immune-brain axis in Drosophila.
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Affiliation(s)
- Florent Fioriti
- Institut de Biologie du Développement de Marseille, Aix-Marseille Université, CNRS UMR 7288 Marseille, France
| | - Aline Rifflet
- Institut Pasteur, Université Paris Cité, CNRS UMR6047, INSERM U1306, 75015 Paris, France
| | - Ivo Gomperts Boneca
- Institut Pasteur, Université Paris Cité, CNRS UMR6047, INSERM U1306, 75015 Paris, France
| | - Olivier Zugasti
- Institut de Biologie du Développement de Marseille, Aix-Marseille Université, CNRS UMR 7288 Marseille, France.
| | - Julien Royet
- Institut de Biologie du Développement de Marseille, Aix-Marseille Université, CNRS UMR 7288 Marseille, France.
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7
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Liguori F, Alberti F, Amadio S, Angelini DF, Pilesi E, Vitale G, Tesoriere G, Borsellino G, Vernì F, Volonté C. Pan-neuronal expression of human mutant SOD1 in Drosophila impairs survival and motor performance, induces early neuroinflammation and chromosome aberrations. Biochim Biophys Acta Mol Basis Dis 2024; 1870:167192. [PMID: 38657911 DOI: 10.1016/j.bbadis.2024.167192] [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: 11/01/2023] [Revised: 04/04/2024] [Accepted: 04/15/2024] [Indexed: 04/26/2024]
Abstract
Several mutations in the SOD1 gene encoding for the antioxidant enzyme Superoxide Dismutase 1, are associated with amyotrophic lateral sclerosis, a rare and devastating disease characterized by motor neuron degeneration and patients' death within 2-5 years from diagnosis. Motor neuron loss and related symptomatology manifest mostly in adult life and, to date, there is still a gap of knowledge on the precise cellular and molecular events preceding neurodegeneration. To deepen our awareness of the early phases of the disease, we leveraged two Drosophila melanogaster models pan-neuronally expressing either the mutation A4V or G85R of the human gene SOD1 (hSOD1A4V or hSOD1G85R). We demonstrate that pan-neuronal expression of the hSOD1A4V or hSOD1G85R pathogenic construct impairs survival and motor performance in transgenic flies. Moreover, protein and transcript analysis on fly heads indicates that mutant hSOD1 induction stimulates the glial marker Repo, up-regulates the IMD/Toll immune pathways through antimicrobial peptides and interferes with oxidative metabolism. Finally, cytological analysis of larval brains demonstrates hSOD1-induced chromosome aberrations. Of note, these parameters are found modulated in a timeframe when neurodegeneration is not detected. The novelty of our work is twofold: we have expressed for the first time hSOD1 mutations in all neurons of Drosophila and confirmed some ALS-related pathological phenotypes in these flies, confirming the power of SOD1 mutations in generating ALS-like phenotypes. Moreover, we have related SOD1 pathogenesis to chromosome aberrations and antimicrobial peptides up-regulation. These findings were unexplored in the SOD1-ALS field.
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Affiliation(s)
- Francesco Liguori
- Experimental Neuroscience and Neurological Disease Models, IRCCS Fondazione Santa Lucia, Via del Fosso di Fiorano 65, 00143 Rome, Italy; Institute for Systems Analysis and Computer Science "Antonio Ruberti" (IASI), National Research Council (CNR), Via dei Taurini 19, 00185 Rome, Italy.
| | - Francesca Alberti
- Experimental Neuroscience and Neurological Disease Models, IRCCS Fondazione Santa Lucia, Via del Fosso di Fiorano 65, 00143 Rome, Italy
| | - Susanna Amadio
- Experimental Neuroscience and Neurological Disease Models, IRCCS Fondazione Santa Lucia, Via del Fosso di Fiorano 65, 00143 Rome, Italy
| | - Daniela Francesca Angelini
- Experimental Neuroscience and Neurological Disease Models, IRCCS Fondazione Santa Lucia, Via del Fosso di Fiorano 65, 00143 Rome, Italy
| | - Eleonora Pilesi
- Department of Biology and Biotechnology "Charles Darwin", Sapienza University of Rome, Piazzale Aldo Moro 5, 00185 Rome, Italy
| | - Giuseppe Vitale
- Experimental Neuroscience and Neurological Disease Models, IRCCS Fondazione Santa Lucia, Via del Fosso di Fiorano 65, 00143 Rome, Italy
| | - Giulia Tesoriere
- Department of Biology and Biotechnology "Charles Darwin", Sapienza University of Rome, Piazzale Aldo Moro 5, 00185 Rome, Italy
| | - Giovanna Borsellino
- Experimental Neuroscience and Neurological Disease Models, IRCCS Fondazione Santa Lucia, Via del Fosso di Fiorano 65, 00143 Rome, Italy
| | - Fiammetta Vernì
- Department of Biology and Biotechnology "Charles Darwin", Sapienza University of Rome, Piazzale Aldo Moro 5, 00185 Rome, Italy
| | - Cinzia Volonté
- Experimental Neuroscience and Neurological Disease Models, IRCCS Fondazione Santa Lucia, Via del Fosso di Fiorano 65, 00143 Rome, Italy; Institute for Systems Analysis and Computer Science "Antonio Ruberti" (IASI), National Research Council (CNR), Via dei Taurini 19, 00185 Rome, Italy.
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8
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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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9
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Zhu Y, Cho K, Lacin H, Zhu Y, DiPaola JT, Wilson BA, Patti GJ, Skeath JB. Loss of dihydroceramide desaturase drives neurodegeneration by disrupting endoplasmic reticulum and lipid droplet homeostasis in glial cells. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.01.01.573836. [PMID: 38260379 PMCID: PMC10802327 DOI: 10.1101/2024.01.01.573836] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/24/2024]
Abstract
Dihydroceramide desaturases convert dihydroceramides to ceramides, the precursors of all complex sphingolipids. Reduction of DEGS1 dihydroceramide desaturase function causes pediatric neurodegenerative disorder hypomyelinating leukodystrophy-18 (HLD-18). We discovered that infertile crescent (ifc), the Drosophila DEGS1 homolog, is expressed primarily in glial cells to promote CNS development by guarding against neurodegeneration. Loss of ifc causes massive dihydroceramide accumulation and severe morphological defects in cortex glia, including endoplasmic reticulum (ER) expansion, failure of neuronal ensheathment, and lipid droplet depletion. RNAi knockdown of the upstream ceramide synthase schlank in glia of ifc mutants rescues ER expansion, suggesting dihydroceramide accumulation in the ER drives this phenotype. RNAi knockdown of ifc in glia but not neurons drives neuronal cell death, suggesting that ifc function in glia promotes neuronal survival. Our work identifies glia as the primary site of disease progression in HLD-18 and may inform on juvenile forms of ALS, which also feature elevated dihydroceramide levels.
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Affiliation(s)
- Yuqing Zhu
- Department of Genetics, Washington University School of Medicine, 4523 Clayton Avenue, St. Louis, MO 63110, USA
| | - Kevin Cho
- Department of Chemistry, Washington University in St. Louis, One Brookings Drive, St. Louis, MO 63130, USA
- Department of Medicine, Washington University School of Medicine, St. Louis, MO 63110, USA
- Center for Mass Spectrometry and Metabolic Tracing, Washington University in St. Louis, One Brookings Drive, St. Louis, MO 63130, USA
| | - Haluk Lacin
- Division of Biological and Biomedical Systems, University of Missouri-Kansas City, Kansas City, MO 64110, USA
| | - Yi Zhu
- Department of Genetics, Washington University School of Medicine, 4523 Clayton Avenue, St. Louis, MO 63110, USA
| | - Jose T DiPaola
- Department of Genetics, Washington University School of Medicine, 4523 Clayton Avenue, St. Louis, MO 63110, USA
| | - Beth A Wilson
- Department of Genetics, Washington University School of Medicine, 4523 Clayton Avenue, St. Louis, MO 63110, USA
| | - Gary J Patti
- Department of Chemistry, Washington University in St. Louis, One Brookings Drive, St. Louis, MO 63130, USA
- Department of Medicine, Washington University School of Medicine, St. Louis, MO 63110, USA
- Center for Mass Spectrometry and Metabolic Tracing, Washington University in St. Louis, One Brookings Drive, St. Louis, MO 63130, USA
| | - James B Skeath
- Department of Genetics, Washington University School of Medicine, 4523 Clayton Avenue, St. Louis, MO 63110, USA
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10
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Park K, Choi H, Han IJ, Asefa WR, Jeong C, Yu S, Jeong H, Choi M, Yoon SE, Kim YJ, Choi MS, Kwon JY. Molecular and cellular organization of odorant binding protein genes in Drosophila. Heliyon 2024; 10:e29358. [PMID: 38694054 PMCID: PMC11058302 DOI: 10.1016/j.heliyon.2024.e29358] [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: 02/22/2024] [Revised: 04/01/2024] [Accepted: 04/05/2024] [Indexed: 05/03/2024] Open
Abstract
Chemosensation is important for the survival and reproduction of animals. The odorant binding proteins (OBPs) are thought to be involved in chemosensation together with chemosensory receptors. While OBPs were initially considered to deliver hydrophobic odorants to olfactory receptors in the aqueous lymph solution, recent studies suggest more complex roles in various organs. Here, we use GAL4 transgenes to systematically analyze the expression patterns of all 52 members of the Obp gene family and 3 related chemosensory protein genes in adult Drosophila, focusing on chemosensory organs such as the antenna, maxillary palp, pharynx, and labellum, and other organs such as the brain, ventral nerve cord, leg, wing, and intestine. The OBPs were observed to express in diverse organs and in multiple cell types, suggesting that these proteins can indeed carry out diverse functional roles. Also, we constructed 10 labellar-expressing Obp mutants, and obtained behavioral evidence that these OBPs may be involved in bitter sensing. The resources we constructed should be useful for future Drosophila OBP gene family research.
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Affiliation(s)
- Keehyun Park
- Department of Biological Sciences, Sungkyunkwan University, Suwon, 16419, Republic of Korea
| | - Hyungjun Choi
- Department of Biological Sciences, Sungkyunkwan University, Suwon, 16419, Republic of Korea
| | - I Joon Han
- Sungkyunkwan University School of Medicine, Seoul, 06351, Republic of Korea
| | - Wayessa Rahel Asefa
- Department of Biological Sciences, Sungkyunkwan University, Suwon, 16419, Republic of Korea
| | - Chaiyoung Jeong
- Department of Biological Sciences, Sungkyunkwan University, Suwon, 16419, Republic of Korea
| | - Seungyun Yu
- Department of Biological Sciences, Sungkyunkwan University, Suwon, 16419, Republic of Korea
| | - Hanhee Jeong
- Department of Biological Sciences, Sungkyunkwan University, Suwon, 16419, Republic of Korea
| | - Minkook Choi
- Department of Oral Biology, Yonsei University College of Dentistry, Seoul, 03722, Republic of Korea
| | - Sung-Eun Yoon
- Korea Drosophila Resource Center, Gwangju, 61005, Republic of Korea
| | - Young-Joon Kim
- Korea Drosophila Resource Center, Gwangju, 61005, Republic of Korea
- School of Life Sciences, Gwangju Institute of Science and Technology (GIST), Gwangju, 61005, Republic of Korea
| | - Min Sung Choi
- Department of Biological Sciences, Sungkyunkwan University, Suwon, 16419, Republic of Korea
| | - Jae Young Kwon
- Department of Biological Sciences, Sungkyunkwan University, Suwon, 16419, Republic of Korea
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11
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Goodman LD, Moulton MJ, Lin G, Bellen HJ. Does glial lipid dysregulation alter sleep in Alzheimer's and Parkinson's disease? Trends Mol Med 2024:S1471-4914(24)00098-4. [PMID: 38755043 DOI: 10.1016/j.molmed.2024.04.010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2024] [Revised: 03/28/2024] [Accepted: 04/10/2024] [Indexed: 05/18/2024]
Abstract
In this opinion article, we discuss potential connections between sleep disturbances observed in Alzheimer's disease (AD) and Parkinson's disease (PD) and the dysregulation of lipids in the brain. Research using Drosophila has highlighted the role of glial-mediated lipid metabolism in sleep and diurnal rhythms. Relevant to AD, the formation of lipid droplets in glia, which occurs in response to elevated neuronal reactive oxygen species (ROS), is required for sleep. In disease models, this process is disrupted, arguing a connection to sleep dysregulation. Relevant to PD, the degradation of neuronally synthesized glucosylceramides by glia requires glucocerebrosidase (GBA, a PD-associated risk factor) and this regulates sleep. Loss of GBA in glia causes an accumulation of glucosylceramides and neurodegeneration. Overall, research primarily using Drosophila has highlighted how dysregulation of glial lipid metabolism may underlie sleep disturbances in neurodegenerative diseases.
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Affiliation(s)
- Lindsey D Goodman
- 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
| | - Matthew J Moulton
- 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
| | - Guang Lin
- 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
| | - 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; Program in Developmental Biology, Baylor College of Medicine, Houston, TX 77030, USA; Department of Neuroscience, Baylor College of Medicine, Houston, TX 77030, USA.
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12
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Nguyen TH, Vicidomini R, Choudhury SD, Han TH, Maric D, Brody T, Serpe M. scRNA-seq data from the larval Drosophila ventral cord provides a resource for studying motor systems function and development. Dev Cell 2024; 59:1210-1230.e9. [PMID: 38569548 PMCID: PMC11078614 DOI: 10.1016/j.devcel.2024.03.016] [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: 06/27/2023] [Revised: 12/05/2023] [Accepted: 03/06/2024] [Indexed: 04/05/2024]
Abstract
The Drosophila larval ventral nerve cord (VNC) shares many similarities with the spinal cord of vertebrates and has emerged as a major model for understanding the development and function of motor systems. Here, we use high-quality scRNA-seq, validated by anatomical identification, to create a comprehensive census of larval VNC cell types. We show that the neural lineages that comprise the adult VNC are already defined, but quiescent, at the larval stage. Using fluorescence-activated cell sorting (FACS)-enriched populations, we separate all motor neuron bundles and link individual neuron clusters to morphologically characterized known subtypes. We discovered a glutamate receptor subunit required for basal neurotransmission and homeostasis at the larval neuromuscular junction. We describe larval glia and endorse the general view that glia perform consistent activities throughout development. This census represents an extensive resource and a powerful platform for future discoveries of cellular and molecular mechanisms in repair, regeneration, plasticity, homeostasis, and behavioral coordination.
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Affiliation(s)
| | | | | | | | - Dragan Maric
- Flow and Imaging Cytometry Core, NINDS, NIH, Bethesda, MD 20892, USA
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13
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Basu R, Preat T, Plaçais PY. Glial metabolism versatility regulates mushroom body-driven behavioral output in Drosophila. Learn Mem 2024; 31:a053823. [PMID: 38862167 PMCID: PMC11199944 DOI: 10.1101/lm.053823.123] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2024] [Accepted: 04/23/2024] [Indexed: 06/13/2024]
Abstract
Providing metabolic support to neurons is now recognized as a major function of glial cells that is conserved from invertebrates to vertebrates. However, research in this field has focused for more than two decades on the relevance of lactate and glial glycolysis for neuronal energy metabolism, while overlooking many other facets of glial metabolism and their impact on neuronal physiology, circuit activity, and behavior. Here, we review recent work that has unveiled new features of glial metabolism, especially in Drosophila, in the modulation of behavioral traits involving the mushroom bodies (MBs). These recent findings reveal that spatially and biochemically distinct modes of glucose-derived neuronal fueling are implemented within the MB in a memory type-specific manner. In addition, cortex glia are endowed with several antioxidant functions, whereas astrocytes can serve as pro-oxidant agents that are beneficial to redox signaling underlying long-term memory. Finally, glial fatty acid oxidation seems to play a dual fail-safe role: first, as a mode of energy production upon glucose shortage, and, second, as a factor underlying the clearance of excessive oxidative load during sleep. Altogether, these integrated studies performed in Drosophila indicate that glial metabolism has a deterministic role on behavior.
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Affiliation(s)
- Ruchira Basu
- Energy & Memory, Brain Plasticity (UMR 8249), CNRS, ESPCI Paris, PSL Research University, 75005 Paris, France
| | - Thomas Preat
- Energy & Memory, Brain Plasticity (UMR 8249), CNRS, ESPCI Paris, PSL Research University, 75005 Paris, France
| | - Pierre-Yves Plaçais
- Energy & Memory, Brain Plasticity (UMR 8249), CNRS, ESPCI Paris, PSL Research University, 75005 Paris, France
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14
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Tsap MI, Yatsenko AS, Hegermann J, Beckmann B, Tsikas D, Shcherbata HR. Unraveling the link between neuropathy target esterase NTE/SWS, lysosomal storage diseases, inflammation, abnormal fatty acid metabolism, and leaky brain barrier. eLife 2024; 13:e98020. [PMID: 38660940 PMCID: PMC11090517 DOI: 10.7554/elife.98020] [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: 03/21/2024] [Accepted: 04/12/2024] [Indexed: 04/26/2024] Open
Abstract
Mutations in Drosophila Swiss cheese (SWS) gene or its vertebrate orthologue neuropathy target esterase (NTE) lead to progressive neuronal degeneration in flies and humans. Despite its enzymatic function as a phospholipase is well established, the molecular mechanism responsible for maintaining nervous system integrity remains unclear. In this study, we found that NTE/SWS is present in surface glia that forms the blood-brain barrier (BBB) and that NTE/SWS is important to maintain its structure and permeability. Importantly, BBB glia-specific expression of Drosophila NTE/SWS or human NTE in the sws mutant background fully rescues surface glial organization and partially restores BBB integrity, suggesting a conserved function of NTE/SWS. Interestingly, sws mutant glia showed abnormal organization of plasma membrane domains and tight junction rafts accompanied by the accumulation of lipid droplets, lysosomes, and multilamellar bodies. Since the observed cellular phenotypes closely resemble the characteristics described in a group of metabolic disorders known as lysosomal storage diseases (LSDs), our data established a novel connection between NTE/SWS and these conditions. We found that mutants with defective BBB exhibit elevated levels of fatty acids, which are precursors of eicosanoids and are involved in the inflammatory response. Also, as a consequence of a permeable BBB, several innate immunity factors are upregulated in an age-dependent manner, while BBB glia-specific expression of NTE/SWS normalizes inflammatory response. Treatment with anti-inflammatory agents prevents the abnormal architecture of the BBB, suggesting that inflammation contributes to the maintenance of a healthy brain barrier. Considering the link between a malfunctioning BBB and various neurodegenerative diseases, gaining a deeper understanding of the molecular mechanisms causing inflammation due to a defective BBB could help to promote the use of anti-inflammatory therapies for age-related neurodegeneration.
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Affiliation(s)
- Mariana I Tsap
- Institute of Cell Biochemistry, Hannover Medical School, Hannover, Germany
| | - Andriy S Yatsenko
- Institute of Cell Biochemistry, Hannover Medical School, Hannover, Germany
| | - Jan Hegermann
- Institute of Functional and Applied Anatomy, Research Core Unit Electron Microscopy, Hannover Medical School, Hannover, Germany
| | - Bibiana Beckmann
- Institute of Toxicology, Hannover Medical School, Hannover, Germany
| | - Dimitrios Tsikas
- Institute of Toxicology, Hannover Medical School, Hannover, Germany
| | - Halyna R Shcherbata
- Institute of Cell Biochemistry, Hannover Medical School, Hannover, Germany
- Mount Desert Island Biological Laboratory, Bar Harbor, United States
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15
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Nelson N, Vita DJ, Broadie K. Experience-dependent glial pruning of synaptic glomeruli during the critical period. Sci Rep 2024; 14:9110. [PMID: 38643298 PMCID: PMC11032375 DOI: 10.1038/s41598-024-59942-3] [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: 02/14/2024] [Accepted: 04/16/2024] [Indexed: 04/22/2024] Open
Abstract
Critical periods are temporally-restricted, early-life windows when sensory experience remodels synaptic connectivity to optimize environmental input. In the Drosophila juvenile brain, critical period experience drives synapse elimination, which is transiently reversible. Within olfactory sensory neuron (OSN) classes synapsing onto single projection neurons extending to brain learning/memory centers, we find glia mediate experience-dependent pruning of OSN synaptic glomeruli downstream of critical period odorant exposure. We find glial projections infiltrate brain neuropil in response to critical period experience, and use Draper (MEGF10) engulfment receptors to prune synaptic glomeruli. Downstream, we find antagonistic Basket (JNK) and Puckered (DUSP) signaling is required for the experience-dependent translocation of activated Basket into glial nuclei. Dependent on this signaling, we find critical period experience drives expression of the F-actin linking signaling scaffold Cheerio (FLNA), which is absolutely essential for the synaptic glomeruli pruning. We find Cheerio mediates experience-dependent regulation of the glial F-actin cytoskeleton for critical period remodeling. These results define a sequential pathway for experience-dependent brain synaptic glomeruli pruning in a strictly-defined critical period; input experience drives neuropil infiltration of glial projections, Draper/MEGF10 receptors activate a Basket/JNK signaling cascade for transcriptional activation, and Cheerio/FLNA induction regulates the glial actin cytoskeleton to mediate targeted synapse phagocytosis.
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Affiliation(s)
- Nichalas Nelson
- Department of Biological Sciences, Vanderbilt University and Medical Center, Nashville, TN, 37235, USA
| | - Dominic J Vita
- Department of Biological Sciences, Vanderbilt University and Medical Center, Nashville, TN, 37235, USA
| | - Kendal Broadie
- Department of Biological Sciences, Vanderbilt University and Medical Center, Nashville, TN, 37235, USA.
- Department of Cell and Developmental Biology, Vanderbilt University and Medical Center, Nashville, TN, 37235, USA.
- Kennedy Center for Research on Human Development, Vanderbilt University and Medical Center, Nashville, TN, 37235, USA.
- Vanderbilt Brain Institute, Vanderbilt University and Medical Center, Nashville, TN, 37235, USA.
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16
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Wang X, Zhai Y, Zheng H. Deciphering the cellular heterogeneity of the insect brain with single-cell RNA sequencing. INSECT SCIENCE 2024; 31:314-327. [PMID: 37702319 DOI: 10.1111/1744-7917.13270] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/24/2023] [Revised: 07/27/2023] [Accepted: 07/31/2023] [Indexed: 09/14/2023]
Abstract
Insects show highly complicated adaptive and sophisticated behaviors, including spatial orientation skills, learning ability, and social interaction. These behaviors are controlled by the insect brain, the central part of the nervous system. The tiny insect brain consists of millions of highly differentiated and interconnected cells forming a complex network. Decades of research has gone into an understanding of which parts of the insect brain possess particular behaviors, but exactly how they modulate these functional consequences needs to be clarified. Detailed description of the brain and behavior is required to decipher the complexity of cell types, as well as their connectivity and function. Single-cell RNA-sequencing (scRNA-seq) has emerged recently as a breakthrough technology to understand the transcriptome at cellular resolution. With scRNA-seq, it is possible to uncover the cellular heterogeneity of brain cells and elucidate their specific functions and state. In this review, we first review the basic structure of insect brains and the links to insect behaviors mainly focusing on learning and memory. Then the scRNA applications on insect brains are introduced by representative studies. Single-cell RNA-seq has allowed researchers to classify cell subpopulations within different insect brain regions, pinpoint single-cell developmental trajectories, and identify gene regulatory networks. These developments empower the advances in neuroscience and shed light on the intricate problems in understanding insect brain functions and behaviors.
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Affiliation(s)
- Xiaofei Wang
- Institute of Plant Protection, Shandong Academy of Agricultural Sciences, Jinan, China
- College of Food Science and Nutritional Engineering, China Agricultural University, Beijing, China
| | - Yifan Zhai
- Institute of Plant Protection, Shandong Academy of Agricultural Sciences, Jinan, China
- Key Laboratory of Natural Enemies Insects, Ministry of Agriculture and Rural Affairs, Jinan, China
- Shandong Provincial Engineering Technology Research Center on Biocontrol of Crops Diseases and In-sect Pests, Jinan, China
| | - Hao Zheng
- Institute of Plant Protection, Shandong Academy of Agricultural Sciences, Jinan, China
- College of Food Science and Nutritional Engineering, China Agricultural University, Beijing, China
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17
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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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18
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Fernandes VM, Auld V, Klämbt C. Glia as Functional Barriers and Signaling Intermediaries. Cold Spring Harb Perspect Biol 2024; 16:a041423. [PMID: 38167424 PMCID: PMC10759988 DOI: 10.1101/cshperspect.a041423] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2024]
Abstract
Glia play a crucial role in providing metabolic support to neurons across different species. To do so, glial cells isolate distinct neuronal compartments from systemic signals and selectively transport specific metabolites and ions to support neuronal development and facilitate neuronal function. Because of their function as barriers, glial cells occupy privileged positions within the nervous system and have also evolved to serve as signaling intermediaries in various contexts. The fruit fly, Drosophila melanogaster, has significantly contributed to our understanding of glial barrier development and function. In this review, we will explore the formation of the glial sheath, blood-brain barrier, and nerve barrier, as well as the significance of glia-extracellular matrix interactions in barrier formation. Additionally, we will delve into the role of glia as signaling intermediaries in regulating nervous system development, function, and response to injury.
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Affiliation(s)
- Vilaiwan M Fernandes
- Department of Cell and Developmental Biology, University College London, London UC1E 6DE, United Kingdom
| | - Vanessa Auld
- Department of Zoology, University of British Columbia, Vancouver, British Columbia V6T 1Z4, Canada
| | - Christian Klämbt
- Institute for Neuro- and Behavioral Biology, University of Münster, Münster 48149, Germany
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19
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Kefi M, Konstantinos P, Balabanidou V, Sarafoglou C, Tsakireli D, Douris V, Monastirioti M, Maréchal JD, Feyereisen R, Vontas J. Insights into unique features of Drosophila CYP4G enzymes. INSECT BIOCHEMISTRY AND MOLECULAR BIOLOGY 2024; 164:104041. [PMID: 38008364 DOI: 10.1016/j.ibmb.2023.104041] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/19/2023] [Revised: 11/12/2023] [Accepted: 11/19/2023] [Indexed: 11/28/2023]
Abstract
The cytochrome P450 enzymes of the CYP4G subfamily are some of the most intriguing insect P450s in terms of structure and function. In Drosophila, CYP4G1 is highly expressed in the oenocytes and is the last enzyme in the biosynthesis of cuticular hydrocarbons, while CYP4G15 is expressed in the brain and is of unknown function. Both proteins have a CYP4G-specific and characteristic amino acid sequence insertion corresponding to a loop between the G and H helices whose function is unclear. Here we address these enigmatic structural and functional features of Drosophila CYP4Gs. First, we used reverse genetics to generate D. melanogaster strains in which all or part of the CYP4G-specific loop was removed from CYP4G1. We showed that the full loop was not needed for proper folding of the P450, but it is essential for function, and that just a short stretch of six amino acids is required for the enzyme's ability to make hydrocarbons. Second, we confirmed by immunocytochemistry that CYP4G15 is expressed in the brain and showed that it is specifically associated with the cortex glia cell subtype. We then expressed CYP4G15 ectopically in oenocytes, revealing that it can produce of a blend of hydrocarbons, albeit to quantitatively lower levels resulting in only a partial rescue of CYP4G1 knockdown flies. The CYP4G1 structural variants studied here should facilitate the biochemical characterization of CYP4G enzymes. Our results also raise the question of the putative role of hydrocarbons and their synthesis by cortex glial cells.
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Affiliation(s)
- Mary Kefi
- Department of Biology, University of Crete, Vassilika Vouton, 70013, Heraklion, Greece; Institute of Molecular Biology and Biotechnology, Foundation for Research and Technology-Hellas, Nikolaou Plastira Street 100, 70013, Heraklion, Greece
| | - Parasyris Konstantinos
- Department of Biology, University of Crete, Vassilika Vouton, 70013, Heraklion, Greece; Institute of Molecular Biology and Biotechnology, Foundation for Research and Technology-Hellas, Nikolaou Plastira Street 100, 70013, Heraklion, Greece
| | - Vasileia Balabanidou
- Institute of Molecular Biology and Biotechnology, Foundation for Research and Technology-Hellas, Nikolaou Plastira Street 100, 70013, Heraklion, Greece
| | - Chara Sarafoglou
- Department of Biology, University of Crete, Vassilika Vouton, 70013, Heraklion, Greece; Institute of Molecular Biology and Biotechnology, Foundation for Research and Technology-Hellas, Nikolaou Plastira Street 100, 70013, Heraklion, Greece
| | - Dimitra Tsakireli
- Institute of Molecular Biology and Biotechnology, Foundation for Research and Technology-Hellas, Nikolaou Plastira Street 100, 70013, Heraklion, Greece; Pesticide Science Laboratory, Department of Crop Science, Agricultural University of Athens, Greece
| | - Vassilis Douris
- Department of Biological Applications and Technology, University of Ioannina, 45110, Ioannina, Greece; Biomedical Research Institute (BRI), Foundation for Research and Technology (FORTH), University Campus, 451 10, Ioannina, Greece
| | - Maria Monastirioti
- Institute of Molecular Biology and Biotechnology, Foundation for Research and Technology-Hellas, Nikolaou Plastira Street 100, 70013, Heraklion, Greece
| | - Jean-Didier Maréchal
- Departament de Química, Universitat Autònoma de Barcelona, Edifici C.n., Cerdanyola del Vallès, 08193, Barcelona, Spain
| | - René Feyereisen
- Laboratory of Agrozoology, Department of Plants and Crops, Faculty of Bioscience Engineering, Ghent University, Belgium.
| | - John Vontas
- Institute of Molecular Biology and Biotechnology, Foundation for Research and Technology-Hellas, Nikolaou Plastira Street 100, 70013, Heraklion, Greece; Pesticide Science Laboratory, Department of Crop Science, Agricultural University of Athens, Greece.
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20
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Miao H, Wei Y, Lee SG, Wu Z, Kaur J, Kim WJ. Glia-specific expression of neuropeptide receptor Lgr4 regulates development and adult physiology in Drosophila. J Neurosci Res 2024; 102:e25271. [PMID: 38284837 DOI: 10.1002/jnr.25271] [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: 02/08/2023] [Revised: 10/10/2023] [Accepted: 10/28/2023] [Indexed: 01/30/2024]
Abstract
Similar to the human brain, Drosophila glia may well be divided into several subtypes that each carries out specific functions. Glial GPCRs play key roles in crosstalk between neurons and glia. Drosophila Lgr4 (dLgr4) is a human relaxin receptor homolog involved in angiogenesis, cardiovascular regulation, collagen remodeling, and wound healing. A recent study suggests that ilp7 might be the ligand for Lgr4 and regulates escape behavior of Drosophila larvae. Here we demonstrate that Drosophila Lgr4 expression in glial cells, not neurons, is necessary for early development, adult behavior, and lifespan. Reducing the Lgr4 level in glial cells disrupts Drosophila development, while knocking down other LGR family members in glia has no impact. Adult-specific knockdown of Lgr4 in glia but not neurons reduce locomotion, male reproductive success, and animal longevity. The investigation of how glial expression of Lgr4 contributes to this behavioral alteration will increase our understanding of how insulin signaling via glia selectively modulates neuronal activity and behavior.
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Affiliation(s)
- Hongyu Miao
- The HIT Center for Life Sciences, Harbin Institute of Technology, Harbin, China
| | - Yanan Wei
- The HIT Center for Life Sciences, Harbin Institute of Technology, Harbin, China
| | - Seung Gee Lee
- Department of Cellular and Molecular Medicine, University of Ottawa, Ottawa, Ontario, Canada
| | - Zekun Wu
- The HIT Center for Life Sciences, Harbin Institute of Technology, Harbin, China
| | - Jasdeep Kaur
- Department of Cellular and Molecular Medicine, University of Ottawa, Ottawa, Ontario, Canada
| | - Woo Jae Kim
- The HIT Center for Life Sciences, Harbin Institute of Technology, Harbin, China
- Department of Cellular and Molecular Medicine, University of Ottawa, Ottawa, Ontario, Canada
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21
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Son W, Jeong HS, Nam DE, Lee AJ, Nam SH, Lee JE, Choi BO, Chung KW. Peripheral Neuropathy and Decreased Locomotion of a RAB40B Mutation in Human and Model Animals. Exp Neurobiol 2023; 32:410-422. [PMID: 38196136 PMCID: PMC10789172 DOI: 10.5607/en23027] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2023] [Revised: 12/13/2023] [Accepted: 12/15/2023] [Indexed: 01/11/2024] Open
Abstract
Rab40 proteins are an atypical subgroup of Rab GTPases containing a unique suppressor of the cytokine signaling (SOCS) domain that is recruited to assemble the CRL5 E3 ligase complex for proteolytic regulation in various biological processes. A nonsense mutation deleting the C-terminal SOCS box in the RAB40B gene was identified in a family with axonal peripheral neuropathy (Charcot-Marie-Tooth disease type 2), and pathogenicity of the mutation was assessed in model organisms of zebrafish and Drosophila. Compared to control fish, zebrafish larvae transformed by the human mutant hRAB40B-Y83X showed a defective swimming pattern of stalling with restricted localization and slower motility. We were consistently able to observe reduced labeling of synaptic markers along neuromuscular junctions of the transformed larvae. In addition to the neurodevelopmental phenotypes, compared to normal hRAB40B expression, we further examined ectopic expression of hRAB40B-Y83X in Drosophila to show a progressive decline of locomotion ability. Decreased ability of locomotion by ubiquitous expression of the human mutation was reproduced not with GAL4 drivers for neuron-specific expression but only when a pan-glial GAL4 driver was applied. Using the ectopic expression model of Drosophila, we identified a genetic interaction in which Cul5 down regulation exacerbated the defective motor performance, showing a consistent loss of SOCS box of the pathogenic RAB40B. Taken together, we could assess the possible gain-of-function of the human RAB40B mutation by comparing behavioral phenotypes in animal models; our results suggest that the mutant phenotypes may be associated with CRL5-mediated proteolytic regulation.
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Affiliation(s)
- Wonseok Son
- Department of Biological Sciences and BK21 Team for Field-oriented BioCore Human Resources Development, Kongju National University, Gongju 32588, Korea
| | - Hui Su Jeong
- Department of Health Sciences and Technology, Samsung Advanced Institute for Health Sciences & Technology, Sungkyunkwan University, Seoul 06351, Korea
| | - Da Eun Nam
- Department of Biological Sciences and BK21 Team for Field-oriented BioCore Human Resources Development, Kongju National University, Gongju 32588, Korea
| | - Ah Jin Lee
- Department of Biological Sciences and BK21 Team for Field-oriented BioCore Human Resources Development, Kongju National University, Gongju 32588, Korea
| | - Soo Hyun Nam
- Cell and Gene Therapy Institute, Samsung Medical Center, Seoul 06351, Korea
| | - Ji Eun Lee
- Department of Health Sciences and Technology, Samsung Advanced Institute for Health Sciences & Technology, Sungkyunkwan University, Seoul 06351, Korea
- Samsung Biomedical Research Institute, Samsung Medical Center, Seoul 06351, Korea
| | - Byung-Ok Choi
- Department of Health Sciences and Technology, Samsung Advanced Institute for Health Sciences & Technology, Sungkyunkwan University, Seoul 06351, Korea
- Cell and Gene Therapy Institute, Samsung Medical Center, Seoul 06351, Korea
- Department of Neurology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul 06351, Korea
| | - Ki Wha Chung
- Department of Biological Sciences and BK21 Team for Field-oriented BioCore Human Resources Development, Kongju National University, Gongju 32588, Korea
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22
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Miyashita T, Murakami K, Kikuchi E, Ofusa K, Mikami K, Endo K, Miyaji T, Moriyama S, Konno K, Muratani H, Moriyama Y, Watanabe M, Horiuchi J, Saitoe M. Glia transmit negative valence information during aversive learning in Drosophila. Science 2023; 382:eadf7429. [PMID: 38127757 DOI: 10.1126/science.adf7429] [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: 11/10/2022] [Accepted: 10/20/2023] [Indexed: 12/23/2023]
Abstract
During Drosophila aversive olfactory conditioning, aversive shock information needs to be transmitted to the mushroom bodies (MBs) to associate with odor information. We report that aversive information is transmitted by ensheathing glia (EG) that surround the MBs. Shock induces vesicular exocytosis of glutamate from EG. Blocking exocytosis impairs aversive learning, whereas activation of EG can replace aversive stimuli during conditioning. Glutamate released from EG binds to N-methyl-d-aspartate receptors in the MBs, but because of Mg2+ block, Ca2+ influx occurs only when flies are simultaneously exposed to an odor. Vesicular exocytosis from EG also induces shock-associated dopamine release, which plays a role in preventing formation of inappropriate associations. These results demonstrate that vesicular glutamate released from EG transmits negative valence information required for associative learning.
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Affiliation(s)
- Tomoyuki Miyashita
- Learning and Memory Project, Tokyo Metropolitan Institute of Medical Science, Tokyo 156-8506, Japan
| | - Kanako Murakami
- Learning and Memory Project, Tokyo Metropolitan Institute of Medical Science, Tokyo 156-8506, Japan
- Department of Biological Science, Graduate School of Science, Tokyo Metropolitan University, Tokyo 192-0397, Japan
| | - Emi Kikuchi
- Learning and Memory Project, Tokyo Metropolitan Institute of Medical Science, Tokyo 156-8506, Japan
| | - Kyouko Ofusa
- Learning and Memory Project, Tokyo Metropolitan Institute of Medical Science, Tokyo 156-8506, Japan
| | - Kyohei Mikami
- Center for Basic Technology Research, Tokyo Metropolitan Institute of Medical Science, Tokyo 156-8506, Japan
| | - Kentaro Endo
- Center for Basic Technology Research, Tokyo Metropolitan Institute of Medical Science, Tokyo 156-8506, Japan
| | - Takaaki Miyaji
- Department of Molecular Membrane Biology, Faculty of Pharmaceutical Sciences, Okayama University, Okayama 700-8530, Japan
- Department of Genomics and Proteomics, Advanced Science Research Center, Okayama University, Okayama 700-8530, Japan
| | - Sawako Moriyama
- Division of Endocrinology and Metabolism, Department of Internal Medicine, School of Medicine, Kurume University, Fukuoka 830-0011, Japan
| | - Kotaro Konno
- Department of Anatomy, Faculty of Medicine, Hokkaido University, Hokkaido 060-8368, Japan
| | - Hinako Muratani
- Learning and Memory Project, Tokyo Metropolitan Institute of Medical Science, Tokyo 156-8506, Japan
- Department of Engineering Science, Graduate School of Informatics and Engineering, The University of Electro-Communications, Tokyo 182-8585, Japan
| | - Yoshinori Moriyama
- Division of Endocrinology and Metabolism, Department of Internal Medicine, School of Medicine, Kurume University, Fukuoka 830-0011, Japan
| | - Masahiko Watanabe
- Department of Anatomy, Faculty of Medicine, Hokkaido University, Hokkaido 060-8368, Japan
| | - Junjiro Horiuchi
- Center for Basic Technology Research, Tokyo Metropolitan Institute of Medical Science, Tokyo 156-8506, Japan
| | - Minoru Saitoe
- Learning and Memory Project, Tokyo Metropolitan Institute of Medical Science, Tokyo 156-8506, Japan
- Center for Basic Technology Research, Tokyo Metropolitan Institute of Medical Science, Tokyo 156-8506, Japan
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23
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Catterson JH, Minkley L, Aspe S, Judd-Mole S, Moura S, Dyson MC, Rajasingam A, Woodling NS, Atilano ML, Ahmad M, Durrant CS, Spires-Jones TL, Partridge L. Protein retention in the endoplasmic reticulum rescues Aβ toxicity in Drosophila. Neurobiol Aging 2023; 132:154-174. [PMID: 37837732 PMCID: PMC10940166 DOI: 10.1016/j.neurobiolaging.2023.09.008] [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: 02/09/2022] [Revised: 09/18/2023] [Accepted: 09/18/2023] [Indexed: 10/16/2023]
Abstract
Amyloid β (Aβ) accumulation is a hallmark of Alzheimer's disease. In adult Drosophila brains, human Aβ overexpression harms climbing and lifespan. It's uncertain whether Aβ is intrinsically toxic or activates downstream neurodegeneration pathways. Our study uncovers a novel protective role against Aβ toxicity: intra-endoplasmic reticulum (ER) protein accumulation with a focus on laminin and collagen subunits. Despite high Aβ, laminin B1 (LanB1) overexpression robustly counters toxicity, suggesting a potential Aβ resistance mechanism. Other laminin subunits and collagen IV also alleviate Aβ toxicity; combining them with LanB1 augments the effect. Imaging reveals ER retention of LanB1 without altering Aβ secretion. LanB1's rescue function operates independently of the IRE1α/XBP1 ER stress response. ER-targeted GFP overexpression also mitigates Aβ toxicity, highlighting broader ER protein retention advantages. Proof-of-principle tests in murine hippocampal slices using mouse Lamb1 demonstrate ER retention in transduced cells, indicating a conserved mechanism. Though ER protein retention generally harms, it could paradoxically counter neuronal Aβ toxicity, offering a new therapeutic avenue for Alzheimer's disease.
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Affiliation(s)
- James H Catterson
- Institute of Healthy Ageing, Genetics, Evolution and Environment, University College London, Darwin Building, Gower Street, London WC1E 6BT, UK; Centre for Discovery Brain Sciences, UK Dementia Research Institute, The University of Edinburgh, 1 George Square, Edinburgh EH8 9JZ, Scotland, UK
| | - Lucy Minkley
- Institute of Healthy Ageing, Genetics, Evolution and Environment, University College London, Darwin Building, Gower Street, London WC1E 6BT, UK
| | - Salomé Aspe
- Institute of Healthy Ageing, Genetics, Evolution and Environment, University College London, Darwin Building, Gower Street, London WC1E 6BT, UK
| | - Sebastian Judd-Mole
- Institute of Healthy Ageing, Genetics, Evolution and Environment, University College London, Darwin Building, Gower Street, London WC1E 6BT, UK
| | - Sofia Moura
- Institute of Healthy Ageing, Genetics, Evolution and Environment, University College London, Darwin Building, Gower Street, London WC1E 6BT, UK
| | - Miranda C Dyson
- Institute of Healthy Ageing, Genetics, Evolution and Environment, University College London, Darwin Building, Gower Street, London WC1E 6BT, UK
| | - Arjunan Rajasingam
- Institute of Healthy Ageing, Genetics, Evolution and Environment, University College London, Darwin Building, Gower Street, London WC1E 6BT, UK
| | - Nathaniel S Woodling
- Institute of Healthy Ageing, Genetics, Evolution and Environment, University College London, Darwin Building, Gower Street, London WC1E 6BT, UK
| | - Magda L Atilano
- Institute of Healthy Ageing, Genetics, Evolution and Environment, University College London, Darwin Building, Gower Street, London WC1E 6BT, UK
| | - Mumtaz Ahmad
- Institute of Healthy Ageing, Genetics, Evolution and Environment, University College London, Darwin Building, Gower Street, London WC1E 6BT, UK
| | - Claire S Durrant
- Centre for Discovery Brain Sciences, UK Dementia Research Institute, The University of Edinburgh, 1 George Square, Edinburgh EH8 9JZ, Scotland, UK
| | - Tara L Spires-Jones
- Centre for Discovery Brain Sciences, UK Dementia Research Institute, The University of Edinburgh, 1 George Square, Edinburgh EH8 9JZ, Scotland, UK
| | - Linda Partridge
- Institute of Healthy Ageing, Genetics, Evolution and Environment, University College London, Darwin Building, Gower Street, London WC1E 6BT, UK; Max Planck Institute for Biology of Ageing, Joseph-Stelzmann-Strasse 9b, 50931 Cologne, Germany.
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24
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Rabah Y, Francés R, Minatchy J, Guédon L, Desnous C, Plaçais PY, Preat T. Glycolysis-derived alanine from glia fuels neuronal mitochondria for memory in Drosophila. Nat Metab 2023; 5:2002-2019. [PMID: 37932430 PMCID: PMC10663161 DOI: 10.1038/s42255-023-00910-y] [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] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/30/2022] [Accepted: 09/20/2023] [Indexed: 11/08/2023]
Abstract
Glucose is the primary source of energy for the brain; however, it remains controversial whether, upon neuronal activation, glucose is primarily used by neurons for ATP production or if it is partially oxidized in astrocytes, as proposed by the astrocyte-neuron lactate shuttle model for glutamatergic neurons. Thus, an in vivo picture of glucose metabolism during cognitive processes is missing. Here, we uncover in Drosophila melanogaster a glia-to-neuron alanine transfer involving alanine aminotransferase that sustains memory formation. Following associative conditioning, glycolysis in glial cells produces alanine, which is back-converted into pyruvate in cholinergic neurons of the olfactory memory center to uphold their increased mitochondrial needs. Alanine, as a mediator of glia-neuron coupling, could be an alternative to lactate in cholinergic systems. In parallel, a dedicated glial glucose transporter imports glucose specifically for long-term memory, by directly transferring it to neurons for use by the pentose phosphate pathway. Our results demonstrate in vivo the compartmentalization of glucose metabolism between neurons and glial cells during memory formation.
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Affiliation(s)
- Yasmine Rabah
- Energy & Memory, Brain Plasticity Unit, CNRS, ESPCI Paris, PSL Research University, Paris, France
| | - Raquel Francés
- Energy & Memory, Brain Plasticity Unit, CNRS, ESPCI Paris, PSL Research University, Paris, France
| | - Julia Minatchy
- Energy & Memory, Brain Plasticity Unit, CNRS, ESPCI Paris, PSL Research University, Paris, France
| | - Laura Guédon
- Energy & Memory, Brain Plasticity Unit, CNRS, ESPCI Paris, PSL Research University, Paris, France
| | - Coraline Desnous
- Energy & Memory, Brain Plasticity Unit, CNRS, ESPCI Paris, PSL Research University, Paris, France
| | - Pierre-Yves Plaçais
- Energy & Memory, Brain Plasticity Unit, CNRS, ESPCI Paris, PSL Research University, Paris, France.
| | - Thomas Preat
- Energy & Memory, Brain Plasticity Unit, CNRS, ESPCI Paris, PSL Research University, Paris, France.
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25
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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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26
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Shu S, Jiang M, Deng X, Yue W, Cao X, Zhang K, Wang Z, He H, Cui J, Wang Q, Qu K, Fang Y. Heterochromatic silencing of immune-related genes in glia is required for BBB integrity and normal lifespan in drosophila. Aging Cell 2023; 22:e13947. [PMID: 37594178 PMCID: PMC10577565 DOI: 10.1111/acel.13947] [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: 02/11/2023] [Revised: 06/21/2023] [Accepted: 07/16/2023] [Indexed: 08/19/2023] Open
Abstract
Glia and neurons face different challenges in aging and may engage different mechanisms to maintain their morphology and functionality. Here, we report that adult-onset downregulation of a Drosophila gene CG32529/GLAD led to shortened lifespan and age-dependent brain degeneration. This regulation exhibited cell type and subtype-specificity, involving mainly surface glia (comprising the BBB) and cortex glia (wrapping neuronal soma) in flies. In accordance, pan-glial knockdown of GLAD disrupted BBB integrity and the glial meshwork. GLAD expression in fly heads decreased with age, and the RNA-seq analysis revealed that the most affected transcriptional changes by RNAi-GLAD were associated with upregulation of immune-related genes. Furthermore, we conducted a series of lifespan rescue experiments and the results indicated that the profound upregulation of immune and related pathways was not the consequence but cause of the degenerative phenotypes of the RNAi-GLAD flies. Finally, we showed that GLAD encoded a heterochromatin-associating protein that bound to the promoters of an array of immune-related genes and kept them silenced during the cell cycle. Together, our findings demonstrate a previously unappreciated role of heterochromatic gene silencing in repressing immunity in fly glia, which is required for maintaining BBB and brain integrity as well as normal lifespan.
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Affiliation(s)
- Shunpan Shu
- Interdisciplinary Research Center on Biology and Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of SciencesShanghaiChina
- University of Chinese Academy of SciencesBeijingChina
| | - Mingsheng Jiang
- Interdisciplinary Research Center on Biology and Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of SciencesShanghaiChina
- University of Chinese Academy of SciencesBeijingChina
| | - Xue Deng
- Interdisciplinary Research Center on Biology and Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of SciencesShanghaiChina
- University of Chinese Academy of SciencesBeijingChina
| | - Wenkai Yue
- Interdisciplinary Research Center on Biology and Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of SciencesShanghaiChina
- University of Chinese Academy of SciencesBeijingChina
| | - Xu Cao
- Interdisciplinary Research Center on Biology and Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of SciencesShanghaiChina
- University of Chinese Academy of SciencesBeijingChina
| | - Kai Zhang
- Interdisciplinary Research Center on Biology and Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of SciencesShanghaiChina
- University of Chinese Academy of SciencesBeijingChina
| | - Zeqing Wang
- Interdisciplinary Research Center on Biology and Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of SciencesShanghaiChina
- University of Chinese Academy of SciencesBeijingChina
| | - Hao He
- Interdisciplinary Research Center on Biology and Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of SciencesShanghaiChina
- University of Chinese Academy of SciencesBeijingChina
| | - Jihong Cui
- Interdisciplinary Research Center on Biology and Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of SciencesShanghaiChina
| | - Qiangqiang Wang
- Interdisciplinary Research Center on Biology and Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of SciencesShanghaiChina
| | - Kun Qu
- Division of Life Sciences and MedicineUniversity of Science and Technology of ChinaHefeiChina
| | - Yanshan Fang
- Interdisciplinary Research Center on Biology and Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of SciencesShanghaiChina
- University of Chinese Academy of SciencesBeijingChina
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27
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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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28
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Ju L, Glastad KM, Sheng L, Gospocic J, Kingwell CJ, Davidson SM, Kocher SD, Bonasio R, Berger SL. Hormonal gatekeeping via the blood-brain barrier governs caste-specific behavior in ants. Cell 2023; 186:4289-4309.e23. [PMID: 37683635 PMCID: PMC10807403 DOI: 10.1016/j.cell.2023.08.002] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2022] [Revised: 05/10/2023] [Accepted: 08/01/2023] [Indexed: 09/10/2023]
Abstract
Here, we reveal an unanticipated role of the blood-brain barrier (BBB) in regulating complex social behavior in ants. Using scRNA-seq, we find localization in the BBB of a key hormone-degrading enzyme called juvenile hormone esterase (Jhe), and we show that this localization governs the level of juvenile hormone (JH3) entering the brain. Manipulation of the Jhe level reprograms the brain transcriptome between ant castes. Although ant Jhe is retained and functions intracellularly within the BBB, we show that Drosophila Jhe is naturally extracellular. Heterologous expression of ant Jhe into the Drosophila BBB alters behavior in fly to mimic what is seen in ants. Most strikingly, manipulation of Jhe levels in ants reprograms complex behavior between worker castes. Our study thus uncovers a remarkable, potentially conserved role of the BBB serving as a molecular gatekeeper for a neurohormonal pathway that regulates social behavior.
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Affiliation(s)
- Linyang Ju
- Department of Biology, School of Arts and Sciences, University of Pennsylvania, Philadelphia, PA 19104, USA; Epigenetics Institute, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104, USA; Department of Cell and Developmental Biology, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104, USA
| | - Karl M Glastad
- Epigenetics Institute, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104, USA; Department of Cell and Developmental Biology, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104, USA.
| | - Lihong Sheng
- Epigenetics Institute, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104, USA; Department of Cell and Developmental Biology, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104, USA
| | - Janko Gospocic
- Epigenetics Institute, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104, USA; Department of Cell and Developmental Biology, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104, USA; Department of Urology and Institute of Neuropathology, Medical Center-University of Freiburg, Freiburg, Germany
| | - Callum J Kingwell
- Department of Ecology and Evolutionary Biology, Princeton University, Princeton, NJ 08544, USA
| | - Shawn M Davidson
- Lewis-Sigler Institute for Genomics, Princeton University, Princeton, NJ 08544, USA
| | - Sarah D Kocher
- Department of Ecology and Evolutionary Biology, Princeton University, Princeton, NJ 08544, USA; Lewis-Sigler Institute for Genomics, Princeton University, Princeton, NJ 08544, USA
| | - Roberto Bonasio
- Epigenetics Institute, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104, USA; Department of Cell and Developmental Biology, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104, USA
| | - Shelley L Berger
- Department of Biology, School of Arts and Sciences, University of Pennsylvania, Philadelphia, PA 19104, USA; Epigenetics Institute, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104, USA; Department of Cell and Developmental Biology, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104, USA; Department of Genetics, Perelman School of Medicine, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104, USA.
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29
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Li H, Aboudhiaf S, Parrot S, Scote-Blachon C, Benetollo C, Lin JS, Seugnet L. Pallidin function in Drosophila surface glia regulates sleep and is dependent on amino acid availability. Cell Rep 2023; 42:113025. [PMID: 37682712 DOI: 10.1016/j.celrep.2023.113025] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2022] [Revised: 06/16/2023] [Accepted: 08/09/2023] [Indexed: 09/10/2023] Open
Abstract
The Pallidin protein is a central subunit of a multimeric complex called biogenesis of lysosome-related organelles complex 1 (BLOC1) that regulates specific endosomal functions and has been linked to schizophrenia. We show here that downregulation of Pallidin and other members of BLOC1 in the surface glia, the Drosophila equivalent of the blood-brain barrier, reduces and delays nighttime sleep in a circadian-clock-dependent manner. In agreement with BLOC1 involvement in amino acid transport, downregulation of the large neutral amino acid transporter 1 (LAT1)-like transporters JhI-21 and mnd, as well as of TOR (target of rapamycin) amino acid signaling, phenocopy Pallidin knockdown. Furthermore, supplementing food with leucine normalizes the sleep/wake phenotypes of Pallidin downregulation, and we identify a role for Pallidin in the subcellular trafficking of JhI-21. Finally, we provide evidence that Pallidin in surface glia is required for GABAergic neuronal activity. These data identify a BLOC1 function linking essential amino acid availability and GABAergic sleep/wake regulation.
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Affiliation(s)
- Hui Li
- Centre de Recherche en Neurosciences de Lyon, Team WAKING, Université Claude Bernard Lyon 1, INSERM U1028, CNRS UMR 5292, 69675 Bron, France
| | - Sami Aboudhiaf
- Centre de Recherche en Neurosciences de Lyon, Team WAKING, Université Claude Bernard Lyon 1, INSERM U1028, CNRS UMR 5292, 69675 Bron, France
| | - Sandrine Parrot
- Centre de Recherche en Neurosciences de Lyon, NeuroDialyTics Facility, Université Claude Bernard Lyon 1, INSERM U1028, CNRS UMR 5292, 69675 Bron, France
| | - Céline Scote-Blachon
- Centre de Recherche en Neurosciences de Lyon, GenCyTi Facility, Université Claude Bernard Lyon 1, INSERM U1028, CNRS UMR 5292, 69675 Bron, France
| | - Claire Benetollo
- Centre de Recherche en Neurosciences de Lyon, GenCyTi Facility, Université Claude Bernard Lyon 1, INSERM U1028, CNRS UMR 5292, 69675 Bron, France
| | - Jian-Sheng Lin
- Centre de Recherche en Neurosciences de Lyon, Team WAKING, Université Claude Bernard Lyon 1, INSERM U1028, CNRS UMR 5292, 69675 Bron, France
| | - Laurent Seugnet
- Centre de Recherche en Neurosciences de Lyon, Team WAKING, Université Claude Bernard Lyon 1, INSERM U1028, CNRS UMR 5292, 69675 Bron, France.
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30
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Krupp S, Hubbard I, Tam O, Hammell GM, Dubnau J. TDP-43 pathology in Drosophila induces glial-cell type specific toxicity that can be ameliorated by knock-down of SF2/SRSF1. PLoS Genet 2023; 19:e1010973. [PMID: 37747929 PMCID: PMC10553832 DOI: 10.1371/journal.pgen.1010973] [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: 05/04/2023] [Revised: 10/05/2023] [Accepted: 09/13/2023] [Indexed: 09/27/2023] Open
Abstract
Accumulation of cytoplasmic inclusions of TAR-DNA binding protein 43 (TDP-43) is seen in both neurons and glia in a range of neurodegenerative disorders, including amyotrophic lateral sclerosis (ALS), frontotemporal dementia (FTD) and Alzheimer's disease (AD). Disease progression involves non-cell autonomous interactions among multiple cell types, including neurons, microglia and astrocytes. We investigated the effects in Drosophila of inducible, glial cell type-specific TDP-43 overexpression, a model that causes TDP-43 protein pathology including loss of nuclear TDP-43 and accumulation of cytoplasmic inclusions. We report that TDP-43 pathology in Drosophila is sufficient to cause progressive loss of each of the 5 glial sub-types. But the effects on organismal survival were most pronounced when TDP-43 pathology was induced in the perineural glia (PNG) or astrocytes. In the case of PNG, this effect is not attributable to loss of the glial population, because ablation of these glia by expression of pro-apoptotic reaper expression has relatively little impact on survival. To uncover underlying mechanisms, we used cell-type-specific nuclear RNA sequencing to characterize the transcriptional changes induced by pathological TDP-43 expression. We identified numerous glial cell-type specific transcriptional changes. Notably, SF2/SRSF1 levels were found to be decreased in both PNG and in astrocytes. We found that further knockdown of SF2/SRSF1 in either PNG or astrocytes lessens the detrimental effects of TDP-43 pathology on lifespan, but extends survival of the glial cells. Thus TDP-43 pathology in astrocytes or PNG causes systemic effects that shorten lifespan and SF2/SRSF1 knockdown rescues the loss of these glia, and also reduces their systemic toxicity to the organism.
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Affiliation(s)
- Sarah Krupp
- Program in Neuroscience, Department of Neurobiology and Behavior, Stony Brook University, New York, United States of America
| | - Isabel Hubbard
- Program in Neuroscience, Department of Neurobiology and Behavior, Stony Brook University, New York, United States of America
| | - Oliver Tam
- Cold Spring Harbor Laboratory, Cold Spring Harbor, New York, United States of America
| | - Gale M. Hammell
- Cold Spring Harbor Laboratory, Cold Spring Harbor, New York, United States of America
| | - Josh Dubnau
- Program in Neuroscience, Department of Neurobiology and Behavior, Stony Brook University, New York, United States of America
- Department of Anesthesiology, Stony Brook School of Medicine, New York, United States of America
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31
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Ferreira AAG, Desplan C. An Atlas of the Developing Drosophila Visual System Glia and Subcellular mRNA Localization of Transcripts in Single Cells. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.08.06.552169. [PMID: 37609218 PMCID: PMC10441313 DOI: 10.1101/2023.08.06.552169] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/24/2023]
Abstract
Glial cells are essential for proper nervous system development and function. To understand glial development and function, we comprehensively annotated glial cells in a single-cell mRNA-sequencing (scRNAseq) atlas of the developing Drosophila visual system. This allowed us to study their developmental trajectories, from larval to adult stages, and to understand how specific types of glia diversify during development. For example, neuropil glia that are initially transcriptionally similar in larvae, split into ensheathing and astrocyte-like glia during pupal stages. Other glial types, such as chiasm glia change gradually during development without splitting into two cell types. The analysis of scRNA-seq allowed us to discover that the transcriptome of glial cell bodies can be distinguished from that of their broken processes. The processes contain distinct enriched mRNAs that were validated in vivo. Therefore, we have identified most glial types in the developing optic lobe and devised a computational approach to identify mRNA species that are localized to cell bodies or cellular processes.
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Affiliation(s)
| | - Claude Desplan
- Department of Biology, New York University, New York, NY, USA
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32
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Dorkenwald S, Matsliah A, Sterling AR, Schlegel P, Yu SC, McKellar CE, Lin A, Costa M, Eichler K, Yin Y, Silversmith W, Schneider-Mizell C, Jordan CS, Brittain D, Halageri A, Kuehner K, Ogedengbe O, Morey R, Gager J, Kruk K, Perlman E, Yang R, Deutsch D, Bland D, Sorek M, Lu R, Macrina T, Lee K, Bae JA, Mu S, Nehoran B, Mitchell E, Popovych S, Wu J, Jia Z, Castro M, Kemnitz N, Ih D, Bates AS, Eckstein N, Funke J, Collman F, Bock DD, Jefferis GS, Seung HS, Murthy M. Neuronal wiring diagram of an adult brain. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.06.27.546656. [PMID: 37425937 PMCID: PMC10327113 DOI: 10.1101/2023.06.27.546656] [Citation(s) in RCA: 33] [Impact Index Per Article: 33.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/11/2023]
Abstract
Connections between neurons can be mapped by acquiring and analyzing electron microscopic (EM) brain images. In recent years, this approach has been applied to chunks of brains to reconstruct local connectivity maps that are highly informative, yet inadequate for understanding brain function more globally. Here, we present the first neuronal wiring diagram of a whole adult brain, containing 5×107 chemical synapses between ~130,000 neurons reconstructed from a female Drosophila melanogaster. The resource also incorporates annotations of cell classes and types, nerves, hemilineages, and predictions of neurotransmitter identities. Data products are available by download, programmatic access, and interactive browsing and made interoperable with other fly data resources. We show how to derive a projectome, a map of projections between regions, from the connectome. We demonstrate the tracing of synaptic pathways and the analysis of information flow from inputs (sensory and ascending neurons) to outputs (motor, endocrine, and descending neurons), across both hemispheres, and between the central brain and the optic lobes. Tracing from a subset of photoreceptors all the way to descending motor pathways illustrates how structure can uncover putative circuit mechanisms underlying sensorimotor behaviors. The technologies and open ecosystem of the FlyWire Consortium set the stage for future large-scale connectome projects in other species.
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Affiliation(s)
- Sven Dorkenwald
- Princeton Neuroscience Institute, Princeton University, Princeton, USA
- Computer Science Department, Princeton University, Princeton, USA
| | - Arie Matsliah
- Princeton Neuroscience Institute, Princeton University, Princeton, USA
| | - Amy R Sterling
- Princeton Neuroscience Institute, Princeton University, Princeton, USA
- Eyewire, Boston, USA
| | - Philipp Schlegel
- Neurobiology Division, MRC Laboratory of Molecular Biology, Cambridge, UK
- Drosophila Connectomics Group, Department of Zoology, University of Cambridge, Cambridge, UK
| | - Szi-chieh Yu
- Princeton Neuroscience Institute, Princeton University, Princeton, USA
| | | | - Albert Lin
- Princeton Neuroscience Institute, Princeton University, Princeton, USA
- Center for the Physics of Biological Function, Princeton University, Princeton, USA
| | - Marta Costa
- Drosophila Connectomics Group, Department of Zoology, University of Cambridge, Cambridge, UK
| | - Katharina Eichler
- Drosophila Connectomics Group, Department of Zoology, University of Cambridge, Cambridge, UK
| | - Yijie Yin
- Drosophila Connectomics Group, Department of Zoology, University of Cambridge, Cambridge, UK
| | - Will Silversmith
- Princeton Neuroscience Institute, Princeton University, Princeton, USA
| | | | - Chris S. Jordan
- Princeton Neuroscience Institute, Princeton University, Princeton, USA
| | | | - Akhilesh Halageri
- Princeton Neuroscience Institute, Princeton University, Princeton, USA
| | - Kai Kuehner
- Princeton Neuroscience Institute, Princeton University, Princeton, USA
| | | | - Ryan Morey
- Princeton Neuroscience Institute, Princeton University, Princeton, USA
| | - Jay Gager
- Princeton Neuroscience Institute, Princeton University, Princeton, USA
| | | | | | - Runzhe Yang
- Princeton Neuroscience Institute, Princeton University, Princeton, USA
- Computer Science Department, Princeton University, Princeton, USA
| | - David Deutsch
- Princeton Neuroscience Institute, Princeton University, Princeton, USA
- Department of Neurobiology, University of Haifa, Haifa, Israel
| | - Doug Bland
- Princeton Neuroscience Institute, Princeton University, Princeton, USA
| | - Marissa Sorek
- Princeton Neuroscience Institute, Princeton University, Princeton, USA
- Eyewire, Boston, USA
| | - Ran Lu
- Princeton Neuroscience Institute, Princeton University, Princeton, USA
| | - Thomas Macrina
- Princeton Neuroscience Institute, Princeton University, Princeton, USA
- Computer Science Department, Princeton University, Princeton, USA
| | - Kisuk Lee
- Princeton Neuroscience Institute, Princeton University, Princeton, USA
- Brain & Cognitive Sciences Department, Massachusetts Institute of Technology, Cambridge, USA
| | - J. Alexander Bae
- Princeton Neuroscience Institute, Princeton University, Princeton, USA
- Electrical and Computer Engineering Department, Princeton University, Princeton, USA
| | - Shang Mu
- Princeton Neuroscience Institute, Princeton University, Princeton, USA
| | - Barak Nehoran
- Princeton Neuroscience Institute, Princeton University, Princeton, USA
- Computer Science Department, Princeton University, Princeton, USA
| | - Eric Mitchell
- Princeton Neuroscience Institute, Princeton University, Princeton, USA
| | - Sergiy Popovych
- Princeton Neuroscience Institute, Princeton University, Princeton, USA
- Computer Science Department, Princeton University, Princeton, USA
| | - Jingpeng Wu
- Princeton Neuroscience Institute, Princeton University, Princeton, USA
| | - Zhen Jia
- Princeton Neuroscience Institute, Princeton University, Princeton, USA
| | - Manuel Castro
- Princeton Neuroscience Institute, Princeton University, Princeton, USA
| | - Nico Kemnitz
- Princeton Neuroscience Institute, Princeton University, Princeton, USA
| | - Dodam Ih
- Princeton Neuroscience Institute, Princeton University, Princeton, USA
| | - Alexander Shakeel Bates
- Neurobiology Division, MRC Laboratory of Molecular Biology, Cambridge, UK
- Drosophila Connectomics Group, Department of Zoology, University of Cambridge, Cambridge, UK
- Harvard Medical School, Boston, USA
- Centre for Neural Circuits and Behaviour, The University of Oxford, Oxford, UK
| | - Nils Eckstein
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, USA
| | - Jan Funke
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, USA
| | | | - Davi D. Bock
- Department of Neurological Sciences, Larner College of Medicine, University of Vermont, Burlington, USA
| | - Gregory S.X.E Jefferis
- Neurobiology Division, MRC Laboratory of Molecular Biology, Cambridge, UK
- Drosophila Connectomics Group, Department of Zoology, University of Cambridge, Cambridge, UK
| | - H. Sebastian Seung
- Princeton Neuroscience Institute, Princeton University, Princeton, USA
- Computer Science Department, Princeton University, Princeton, USA
| | - Mala Murthy
- Princeton Neuroscience Institute, Princeton University, Princeton, USA
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Jindal DA, Leier HC, Salazar G, Foden AJ, Seitz EA, Wilkov AJ, Coutinho-Budd JC, Broihier HT. Early Draper-mediated glial refinement of neuropil architecture and synapse number in the Drosophila antennal lobe. Front Cell Neurosci 2023; 17:1166199. [PMID: 37333889 PMCID: PMC10272751 DOI: 10.3389/fncel.2023.1166199] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2023] [Accepted: 05/15/2023] [Indexed: 06/20/2023] Open
Abstract
Glial phagocytic activity refines connectivity, though molecular mechanisms regulating this exquisitely sensitive process are incompletely defined. We developed the Drosophila antennal lobe as a model for identifying molecular mechanisms underlying glial refinement of neural circuits in the absence of injury. Antennal lobe organization is stereotyped and characterized by individual glomeruli comprised of unique olfactory receptor neuronal (ORN) populations. The antennal lobe interacts extensively with two glial subtypes: ensheathing glia wrap individual glomeruli, while astrocytes ramify considerably within them. Phagocytic roles for glia in the uninjured antennal lobe are largely unknown. Thus, we tested whether Draper regulates ORN terminal arbor size, shape, or presynaptic content in two representative glomeruli: VC1 and VM7. We find that glial Draper limits the size of individual glomeruli and restrains their presynaptic content. Moreover, glial refinement is apparent in young adults, a period of rapid terminal arbor and synapse growth, indicating that synapse addition and elimination occur simultaneously. Draper has been shown to be expressed in ensheathing glia; unexpectedly, we find it expressed at high levels in late pupal antennal lobe astrocytes. Surprisingly, Draper plays differential roles in ensheathing glia and astrocytes in VC1 and VM7. In VC1, ensheathing glial Draper plays a more significant role in shaping glomerular size and presynaptic content; while in VM7, astrocytic Draper plays the larger role. Together, these data indicate that astrocytes and ensheathing glia employ Draper to refine circuitry in the antennal lobe before the terminal arbors reach their mature form and argue for local heterogeneity of neuron-glia interactions.
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Affiliation(s)
- Darren A. Jindal
- Department of Neurosciences, Case Western Reserve University School of Medicine, Cleveland, OH, United States
| | - Hans C. Leier
- Department of Neurosciences, Case Western Reserve University School of Medicine, Cleveland, OH, United States
| | - Gabriela Salazar
- Department of Neuroscience, University of Virginia School of Medicine, Charlottesville, VA, United States
| | - Alexander J. Foden
- Department of Neurosciences, Case Western Reserve University School of Medicine, Cleveland, OH, United States
| | - Elizabeth A. Seitz
- Department of Neurosciences, Case Western Reserve University School of Medicine, Cleveland, OH, United States
| | - Abigail J. Wilkov
- Department of Neurosciences, Case Western Reserve University School of Medicine, Cleveland, OH, United States
| | - Jaeda C. Coutinho-Budd
- Department of Neuroscience, University of Virginia School of Medicine, Charlottesville, VA, United States
| | - Heather T. Broihier
- Department of Neurosciences, Case Western Reserve University School of Medicine, Cleveland, OH, United States
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34
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Wu T, Deger JM, Ye H, Guo C, Dhindsa J, Pekarek BT, Al-Ouran R, Liu Z, Al-Ramahi I, Botas J, Shulman JM. Tau polarizes an aging transcriptional signature to excitatory neurons and glia. eLife 2023; 12:e85251. [PMID: 37219079 PMCID: PMC10259480 DOI: 10.7554/elife.85251] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2022] [Accepted: 05/22/2023] [Indexed: 05/24/2023] Open
Abstract
Aging is a major risk factor for Alzheimer's disease (AD), and cell-type vulnerability underlies its characteristic clinical manifestations. We have performed longitudinal, single-cell RNA-sequencing in Drosophila with pan-neuronal expression of human tau, which forms AD neurofibrillary tangle pathology. Whereas tau- and aging-induced gene expression strongly overlap (93%), they differ in the affected cell types. In contrast to the broad impact of aging, tau-triggered changes are strongly polarized to excitatory neurons and glia. Further, tau can either activate or suppress innate immune gene expression signatures in a cell-type-specific manner. Integration of cellular abundance and gene expression pinpoints nuclear factor kappa B signaling in neurons as a marker for cellular vulnerability. We also highlight the conservation of cell-type-specific transcriptional patterns between Drosophila and human postmortem brain tissue. Overall, our results create a resource for dissection of dynamic, age-dependent gene expression changes at cellular resolution in a genetically tractable model of tauopathy.
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Affiliation(s)
- Timothy Wu
- Jan and Dan Duncan Neurological Research Institute, Texas Children’s HospitalHoustonUnited States
- Medical Scientist Training Program, Baylor College of MedicineHoustonUnited States
| | - Jennifer M Deger
- Jan and Dan Duncan Neurological Research Institute, Texas Children’s HospitalHoustonUnited States
- Medical Scientist Training Program, Baylor College of MedicineHoustonUnited States
- Department of Molecular and Human Genetics, Baylor College of MedicineHoustonUnited States
- Department of Neuroscience, Baylor College of MedicineHoustonUnited States
| | - Hui Ye
- Jan and Dan Duncan Neurological Research Institute, Texas Children’s HospitalHoustonUnited States
- Department of Neurology, Baylor College of MedicineHoustonUnited States
| | - Caiwei Guo
- Jan and Dan Duncan Neurological Research Institute, Texas Children’s HospitalHoustonUnited States
- Department of Molecular and Human Genetics, Baylor College of MedicineHoustonUnited States
- Department of Neuroscience, Baylor College of MedicineHoustonUnited States
| | - Justin Dhindsa
- Jan and Dan Duncan Neurological Research Institute, Texas Children’s HospitalHoustonUnited States
- Medical Scientist Training Program, Baylor College of MedicineHoustonUnited States
| | - Brandon T Pekarek
- Jan and Dan Duncan Neurological Research Institute, Texas Children’s HospitalHoustonUnited States
| | - Rami Al-Ouran
- Jan and Dan Duncan Neurological Research Institute, Texas Children’s HospitalHoustonUnited States
| | - Zhandong Liu
- Jan and Dan Duncan Neurological Research Institute, Texas Children’s HospitalHoustonUnited States
- Department of Pediatrics, Baylor College of MedicineHoustonUnited States
- Center for Alzheimer’s and Neurodegenerative Diseases, Baylor College of MedicineHoustonUnited States
| | - Ismael Al-Ramahi
- Jan and Dan Duncan Neurological Research Institute, Texas Children’s HospitalHoustonUnited States
- Center for Alzheimer’s and Neurodegenerative Diseases, Baylor College of MedicineHoustonUnited States
| | - Juan Botas
- Jan and Dan Duncan Neurological Research Institute, Texas Children’s HospitalHoustonUnited States
- Center for Alzheimer’s and Neurodegenerative Diseases, Baylor College of MedicineHoustonUnited States
| | - Joshua M Shulman
- Jan and Dan Duncan Neurological Research Institute, Texas Children’s HospitalHoustonUnited States
- Department of Molecular and Human Genetics, Baylor College of MedicineHoustonUnited States
- Department of Neuroscience, Baylor College of MedicineHoustonUnited States
- Department of Neurology, Baylor College of MedicineHoustonUnited States
- Center for Alzheimer’s and Neurodegenerative Diseases, Baylor College of MedicineHoustonUnited States
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35
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Krupp S, Tam O, Hammell MG, Dubnau J. TDP-43 pathology in Drosophila induces glial-cell type specific toxicity that can be ameliorated by knock-down of SF2/SRSF1. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.05.04.539439. [PMID: 37205372 PMCID: PMC10187300 DOI: 10.1101/2023.05.04.539439] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
Accumulation of cytoplasmic inclusions of TAR-DNA binding protein 43 (TDP-43) is seen in both neurons and glia in a range of neurodegenerative disorders, including amyotrophic lateral sclerosis (ALS), frontotemporal dementia (FTD) and Alzheimer's disease (AD). Disease progression involves non-cell autonomous interactions among multiple cell types, including neurons, microglia and astrocytes. We investigated the effects in Drosophila of inducible, glial cell type-specific TDP-43 overexpression, a model that causes TDP-43 protein pathology including loss of nuclear TDP-43 and accumulation of cytoplasmic inclusions. We report that TDP-43 pathology in Drosophila is sufficient to cause progressive loss of each of the 5 glial sub-types. But the effects on organismal survival were most pronounced when TDP-43 pathology was induced in the perineural glia (PNG) or astrocytes. In the case of PNG, this effect is not attributable to loss of the glial population, because ablation of these glia by expression of pro-apoptotic reaper expression has relatively little impact on survival. To uncover underlying mechanisms, we used cell-type-specific nuclear RNA sequencing to characterize the transcriptional changes induced by pathological TDP-43 expression. We identified numerous glial cell-type specific transcriptional changes. Notably, SF2/SRSF1 levels were found to be decreased in both PNG and in astrocytes. We found that further knockdown of SF2/SRSF1 in either PNG or astrocytes lessens the detrimental effects of TDP-43 pathology on lifespan, but extends survival of the glial cells. Thus TDP-43 pathology in astrocytes or PNG causes systemic effects that shorten lifespan and SF2/SRSF1 knockdown rescues the loss of these glia, and also reduces their systemic toxicity to the organism.
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Affiliation(s)
- S. Krupp
- Program in Neuroscience, Department of Neurobiology and Behavior, Stony Brook University, NY 11794, USA
| | - O Tam
- Cold Spring Harbor Laboratory, 1 Bungtown road, Cold Spring Harbor, NY.,11794
| | - M Gale Hammell
- Cold Spring Harbor Laboratory, 1 Bungtown road, Cold Spring Harbor, NY.,11794
| | - J Dubnau
- Program in Neuroscience, Department of Neurobiology and Behavior, Stony Brook University, NY 11794, USA
- Department of Anesthesiology, Stony Brook School of Medicine, NY 11794, USA
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36
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Li F, Artiushin G, Sehgal A. Modulation of sleep by trafficking of lipids through the Drosophila blood-brain barrier. eLife 2023; 12:e86336. [PMID: 37140181 PMCID: PMC10205086 DOI: 10.7554/elife.86336] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2023] [Accepted: 04/11/2023] [Indexed: 05/05/2023] Open
Abstract
Endocytosis through Drosophila glia is a significant determinant of sleep amount and occurs preferentially during sleep in glia of the blood-brain barrier (BBB). To identify metabolites whose trafficking is mediated by sleep-dependent endocytosis, we conducted metabolomic analysis of flies that have increased sleep due to a block in glial endocytosis. We report that acylcarnitines, fatty acids conjugated to carnitine to promote their transport, accumulate in heads of these animals. In parallel, to identify transporters and receptors whose loss contributes to the sleep phenotype caused by blocked endocytosis, we screened genes enriched in barrier glia for effects on sleep. We find that knockdown of lipid transporters LRP1&2 or of carnitine transporters ORCT1&2 increases sleep. In support of the idea that the block in endocytosis affects trafficking through specific transporters, knockdown of LRP or ORCT transporters also increases acylcarnitines in heads. We propose that lipid species, such as acylcarnitines, are trafficked through the BBB via sleep-dependent endocytosis, and their accumulation reflects an increased need for sleep.
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Affiliation(s)
- Fu Li
- Howard Hughes Medical Institute and Chronobiology and Sleep Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Perelman School of Medicine, University of PennsylvaniaPhiladelphiaUnited States
| | - Gregory Artiushin
- Howard Hughes Medical Institute and Chronobiology and Sleep Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Perelman School of Medicine, University of PennsylvaniaPhiladelphiaUnited States
| | - Amita Sehgal
- Howard Hughes Medical Institute and Chronobiology and Sleep Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Perelman School of Medicine, University of PennsylvaniaPhiladelphiaUnited States
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37
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Chung HL, Ye Q, Park YJ, Zuo Z, Mok JW, Kanca O, Tattikota SG, Lu S, Perrimon N, Lee HK, Bellen HJ. Very-long-chain fatty acids induce glial-derived sphingosine-1-phosphate synthesis, secretion, and neuroinflammation. Cell Metab 2023; 35:855-874.e5. [PMID: 37084732 PMCID: PMC10160010 DOI: 10.1016/j.cmet.2023.03.022] [Citation(s) in RCA: 17] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/12/2022] [Revised: 01/10/2023] [Accepted: 03/29/2023] [Indexed: 04/23/2023]
Abstract
VLCFAs (very-long-chain fatty acids) are the most abundant fatty acids in myelin. Hence, during demyelination or aging, glia are exposed to higher levels of VLCFA than normal. We report that glia convert these VLCFA into sphingosine-1-phosphate (S1P) via a glial-specific S1P pathway. Excess S1P causes neuroinflammation, NF-κB activation, and macrophage infiltration into the CNS. Suppressing the function of S1P in fly glia or neurons, or administration of Fingolimod, an S1P receptor antagonist, strongly attenuates the phenotypes caused by excess VLCFAs. In contrast, elevating the VLCFA levels in glia and immune cells exacerbates these phenotypes. Elevated VLCFA and S1P are also toxic in vertebrates based on a mouse model of multiple sclerosis (MS), experimental autoimmune encephalomyelitis (EAE). Indeed, reducing VLCFA with bezafibrate ameliorates the phenotypes. Moreover, simultaneous use of bezafibrate and fingolimod synergizes to improve EAE, suggesting that lowering VLCFA and S1P is a treatment avenue for MS.
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Affiliation(s)
- 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; Howard Hughes Medical Institute, Baylor College of Medicine, Houston, TX 77030, USA.
| | - Qi Ye
- Jan and Dan Duncan Neurological Research Institute, Texas Children's Hospital, Houston, TX 77030, USA; Department of Pediatrics, Section of Neurology, Baylor College of Medicine, Houston, TX 77030, USA
| | - Ye-Jin Park
- 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
| | - Zhongyuan Zuo
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA
| | - Jung-Wan Mok
- 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
| | - Oguz Kanca
- 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
| | - Nobert Perrimon
- Department of Genetics, Blavatnik Institute, Harvard Medical School, Boston, MA, USA; Howard Hughes Medical Institute and Department of Genetics, Harvard Medical School, Boston, MA, USA
| | - Hyun Kyoung Lee
- Jan and Dan Duncan Neurological Research Institute, Texas Children's Hospital, Houston, TX 77030, USA; Department of Pediatrics, Section of Neurology, Baylor College of Medicine, Houston, TX 77030, USA.
| | - 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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Sheng L, Shields EJ, Gospocic J, Sorida M, Ju L, Byrns CN, Carranza F, Berger SL, Bonini N, Bonasio R. Ensheathing glia promote increased lifespan and healthy brain aging. Aging Cell 2023; 22:e13803. [PMID: 36840361 PMCID: PMC10186613 DOI: 10.1111/acel.13803] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2022] [Revised: 02/07/2023] [Accepted: 02/08/2023] [Indexed: 02/26/2023] Open
Abstract
Glia have an emergent role in brain aging and disease. In the Drosophila melanogaster brain, ensheathing glia function as phagocytic cells and respond to acute neuronal damage, analogous to mammalian microglia. We previously reported changes in glia composition over the life of ants and fruit flies, including a decline in the relative proportion of ensheathing glia with time. How these changes influence brain health and life expectancy is unknown. Here, we show that ensheathing glia but not astrocytes decrease in number during Drosophila melanogaster brain aging. The remaining ensheathing glia display dysregulated expression of genes involved in lipid metabolism and apoptosis, which may lead to lipid droplet accumulation, cellular dysfunction, and death. Inhibition of apoptosis rescued the decline of ensheathing glia with age, improved the neuromotor performance of aged flies, and extended lifespan. Furthermore, an expanded ensheathing glia population prevented amyloid-beta accumulation in a fly model of Alzheimer's disease and delayed the premature death of the diseased animals. These findings suggest that ensheathing glia play a vital role in regulating brain health and animal longevity.
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Affiliation(s)
- Lihong Sheng
- State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain ScienceInstitutes of Brain Science, Fudan UniversityShanghaiChina
- Epigenetics InstituteUniversity of Pennsylvania Perelman School of MedicinePhiladelphiaPennsylvaniaUSA
- Department of Cell and Developmental BiologyUniversity of Pennsylvania Perelman School of MedicinePhiladelphiaPennsylvaniaUSA
| | - Emily J. Shields
- Epigenetics InstituteUniversity of Pennsylvania Perelman School of MedicinePhiladelphiaPennsylvaniaUSA
- Department of Cell and Developmental BiologyUniversity of Pennsylvania Perelman School of MedicinePhiladelphiaPennsylvaniaUSA
- Department of Urology and Institute of NeuropathologyMedical Center–University of FreiburgFreiburgGermany
| | - Janko Gospocic
- Epigenetics InstituteUniversity of Pennsylvania Perelman School of MedicinePhiladelphiaPennsylvaniaUSA
- Department of Cell and Developmental BiologyUniversity of Pennsylvania Perelman School of MedicinePhiladelphiaPennsylvaniaUSA
- Department of Urology and Institute of NeuropathologyMedical Center–University of FreiburgFreiburgGermany
| | - Masato Sorida
- Epigenetics InstituteUniversity of Pennsylvania Perelman School of MedicinePhiladelphiaPennsylvaniaUSA
- Department of Cell and Developmental BiologyUniversity of Pennsylvania Perelman School of MedicinePhiladelphiaPennsylvaniaUSA
| | - Linyang Ju
- Epigenetics InstituteUniversity of Pennsylvania Perelman School of MedicinePhiladelphiaPennsylvaniaUSA
- Department of Cell and Developmental BiologyUniversity of Pennsylvania Perelman School of MedicinePhiladelphiaPennsylvaniaUSA
| | - China N. Byrns
- Medical Scientist Training ProgramUniversity of Pennsylvania Perelman School of MedicinePhiladelphiaPennsylvaniaUSA
- Neuroscience Graduate GroupUniversity of PennsylvaniaPhiladelphiaPennsylvaniaUSA
| | - Faith Carranza
- Department of BiologyUniversity of PennsylvaniaPhiladelphiaPennsylvaniaUSA
| | - Shelley L. Berger
- Epigenetics InstituteUniversity of Pennsylvania Perelman School of MedicinePhiladelphiaPennsylvaniaUSA
- Department of Cell and Developmental BiologyUniversity of Pennsylvania Perelman School of MedicinePhiladelphiaPennsylvaniaUSA
- Department of BiologyUniversity of PennsylvaniaPhiladelphiaPennsylvaniaUSA
- Department of GeneticsUniversity of Pennsylvania Perelman School of MedicinePhiladelphiaPennsylvaniaUSA
| | - Nancy Bonini
- Neuroscience Graduate GroupUniversity of PennsylvaniaPhiladelphiaPennsylvaniaUSA
- Department of BiologyUniversity of PennsylvaniaPhiladelphiaPennsylvaniaUSA
| | - Roberto Bonasio
- Epigenetics InstituteUniversity of Pennsylvania Perelman School of MedicinePhiladelphiaPennsylvaniaUSA
- Department of Cell and Developmental BiologyUniversity of Pennsylvania Perelman School of MedicinePhiladelphiaPennsylvaniaUSA
- Department of Urology and Institute of NeuropathologyMedical Center–University of FreiburgFreiburgGermany
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39
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Hernandez SJ, Lim RG, Onur T, Dane MA, Smith R, Wang K, Jean GEH, Reyes-Ortiz A, Devlin K, Miramontes R, Wu J, Casale M, Kilburn D, Heiser LM, Korkola JE, Van Vactor D, Botas J, Thompson-Peer KL, Thompson LM. An altered extracellular matrix-integrin interface contributes to Huntington's disease-associated CNS dysfunction in glial and vascular cells. Hum Mol Genet 2023; 32:1483-1496. [PMID: 36547263 PMCID: PMC10117161 DOI: 10.1093/hmg/ddac303] [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: 09/13/2022] [Revised: 11/01/2022] [Accepted: 11/15/2022] [Indexed: 12/24/2022] Open
Abstract
Astrocytes and brain endothelial cells are components of the neurovascular unit that comprises the blood-brain barrier (BBB) and their dysfunction contributes to pathogenesis in Huntington's disease (HD). Defining the contribution of these cells to disease can inform cell-type-specific effects and uncover new disease-modifying therapeutic targets. These cells express integrin (ITG) adhesion receptors that anchor the cells to the extracellular matrix (ECM) to maintain the integrity of the BBB. We used HD patient-derived induced pluripotent stem cell (iPSC) modeling to study the ECM-ITG interface in astrocytes and brain microvascular endothelial cells and found ECM-ITG dysregulation in human iPSC-derived cells that may contribute to the dysfunction of the BBB in HD. This disruption has functional consequences since reducing ITG expression in glia in an HD Drosophila model suppressed disease-associated CNS dysfunction. Since ITGs can be targeted therapeutically and manipulating ITG signaling prevents neurodegeneration in other diseases, defining the role of ITGs in HD may provide a novel strategy of intervention to slow CNS pathophysiology to treat HD.
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Affiliation(s)
- Sarah J Hernandez
- Department of Neurobiology and Behavior, University of California Irvine, Irvine, CA 92697, USA
| | - Ryan G Lim
- Institute for Memory Impairments and Neurological Disorders, University of California Irvine, Irvine, CA 92697, USA
| | - Tarik Onur
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, USA
- Jan and Dan Duncan Neurological Research Institute at Texas Children’s Hospital, Houston, TX, USA
- Genetics & Genomics Graduate Program, Baylor College of Medicine, Houston, TX 77030, USA
| | - Mark A Dane
- Department of Biomedical Engineering, OHSU, Portland, OR 97239, USA
| | - Rebecca Smith
- Department of Biomedical Engineering, OHSU, Portland, OR 97239, USA
| | - Keona Wang
- Department of Neurobiology and Behavior, University of California Irvine, Irvine, CA 92697, USA
| | - Grace En-Hway Jean
- Department of Developmental and Cell Biology, University of California, Irvine, CA 92697, USA
| | - Andrea Reyes-Ortiz
- Department of Biological Chemistry, University of California Irvine, Irvine, CA 92697, USA
| | - Kaylyn Devlin
- Department of Biomedical Engineering, OHSU, Portland, OR 97239, USA
| | - Ricardo Miramontes
- Institute for Memory Impairments and Neurological Disorders, University of California Irvine, Irvine, CA 92697, USA
| | - Jie Wu
- Department of Biological Chemistry, University of California Irvine, Irvine, CA 92697, USA
| | - Malcolm Casale
- Department of Neurobiology and Behavior, University of California Irvine, Irvine, CA 92697, USA
| | - David Kilburn
- Department of Biomedical Engineering, OHSU, Portland, OR 97239, USA
| | - Laura M Heiser
- Department of Biomedical Engineering, OHSU, Portland, OR 97239, USA
- OHSU Knight Cancer Institute, Portland, OR 97239, USA
| | - James E Korkola
- Department of Biomedical Engineering, OHSU, Portland, OR 97239, USA
- OHSU Knight Cancer Institute, Portland, OR 97239, USA
| | - David Van Vactor
- Department of Cell Biology, Harvard Medical School, Boston, MA 02115, USA
| | - Juan Botas
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, USA
- Jan and Dan Duncan Neurological Research Institute at Texas Children’s Hospital, Houston, TX, USA
- Genetics & Genomics Graduate Program, Baylor College of Medicine, Houston, TX 77030, USA
- Quantitative & Computational Biosciences, Baylor College of Medicine, Houston, TX 77030, USA
| | - Katherine L Thompson-Peer
- Department of Developmental and Cell Biology, University of California, Irvine, CA 92697, USA
- Reeve-Irvine Research Center, University of California, Irvine, CA 92697, USA
- Center for the Neurobiology of Learning and Memory, University of California, Irvine, CA 92697, USA
- Sue and Bill Gross Stem Cell Research Center, University of California Irvine, Irvine, CA 92697, USA
| | - Leslie M Thompson
- Department of Neurobiology and Behavior, University of California Irvine, Irvine, CA 92697, USA
- Institute for Memory Impairments and Neurological Disorders, University of California Irvine, Irvine, CA 92697, USA
- Department of Biological Chemistry, University of California Irvine, Irvine, CA 92697, USA
- Center for the Neurobiology of Learning and Memory, University of California, Irvine, CA 92697, USA
- Sue and Bill Gross Stem Cell Research Center, University of California Irvine, Irvine, CA 92697, USA
- Department of Psychiatry and Human Behavior, University of California Irvine, Irvine, CA 92697, USA
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Fischer ML, Fabian B, Pauchet Y, Wielsch N, Sachse S, Vilcinskas A, Vogel H. An Assassin's Secret: Multifunctional Cytotoxic Compounds in the Predation Venom of the Assassin Bug Psytalla horrida (Reduviidae, Hemiptera). Toxins (Basel) 2023; 15:toxins15040302. [PMID: 37104240 PMCID: PMC10144120 DOI: 10.3390/toxins15040302] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2023] [Revised: 04/17/2023] [Accepted: 04/18/2023] [Indexed: 04/28/2023] Open
Abstract
Predatory assassin bugs produce venomous saliva that enables them to overwhelm, kill, and pre-digest large prey animals. Venom from the posterior main gland (PMG) of the African assassin bug Psytalla horrida has strong cytotoxic effects, but the responsible compounds are yet unknown. Using cation-exchange chromatography, we fractionated PMG extracts from P. horrida and screened the fractions for toxicity. Two venom fractions strongly affected insect cell viability, bacterial growth, erythrocyte integrity, and intracellular calcium levels in Drosophila melanogaster olfactory sensory neurons. LC-MS/MS analysis revealed that both fractions contained gelsolin, redulysins, S1 family peptidases, and proteins from the uncharacterized venom protein family 2. Synthetic peptides representing the putative lytic domain of redulysins had strong antimicrobial activity against Escherichia coli and/or Bacillus subtilis but only weak toxicity towards insect or mammalian cells, indicating a primary role in preventing the intake of microbial pathogens. In contrast, a recombinant venom protein family 2 protein significantly reduced insect cell viability but exhibited no antibacterial or hemolytic activity, suggesting that it plays a role in prey overwhelming and killing. The results of our study show that P. horrida secretes multiple cytotoxic compounds targeting different organisms to facilitate predation and antimicrobial defense.
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Affiliation(s)
- Maike Laura Fischer
- Department of Insect Symbiosis, Max Planck Institute for Chemical Ecology, 07745 Jena, Germany
| | - Benjamin Fabian
- Research Group Olfactory Coding, Max Planck Institute for Chemical Ecology, 07745 Jena, Germany
| | - Yannick Pauchet
- Department of Insect Symbiosis, Max Planck Institute for Chemical Ecology, 07745 Jena, Germany
| | - Natalie Wielsch
- Research Group Mass Spectrometry/Proteomics, Max Planck Institute for Chemical Ecology, 07745 Jena, Germany
| | - Silke Sachse
- Research Group Olfactory Coding, Max Planck Institute for Chemical Ecology, 07745 Jena, Germany
| | - Andreas Vilcinskas
- Institute for Insect Biotechnology, Justus Liebig University, 35392 Giessen, Germany
- Branch Bioresources of the Fraunhofer Institute for Molecular Biology and Applied Ecology, 35392 Giessen, Germany
| | - Heiko Vogel
- Department of Insect Symbiosis, Max Planck Institute for Chemical Ecology, 07745 Jena, Germany
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41
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Ye C, Behnke JA, Hardin KR, Zheng JQ. Drosophila melanogaster as a model to study age and sex differences in brain injury and neurodegeneration after mild head trauma. Front Neurosci 2023; 17:1150694. [PMID: 37077318 PMCID: PMC10106652 DOI: 10.3389/fnins.2023.1150694] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2023] [Accepted: 03/09/2023] [Indexed: 04/05/2023] Open
Abstract
Repetitive physical insults to the head, including those that elicit mild traumatic brain injury (mTBI), are a known risk factor for a variety of neurodegenerative conditions including Alzheimer's disease (AD), Parkinson's disease (PD), and chronic traumatic encephalopathy (CTE). Although most individuals who sustain mTBI typically achieve a seemingly full recovery within a few weeks, a subset experience delayed-onset symptoms later in life. As most mTBI research has focused on the acute phase of injury, there is an incomplete understanding of mechanisms related to the late-life emergence of neurodegeneration after early exposure to mild head trauma. The recent adoption of Drosophila-based brain injury models provides several unique advantages over existing preclinical animal models, including a tractable framework amenable to high-throughput assays and short relative lifespan conducive to lifelong mechanistic investigation. The use of flies also provides an opportunity to investigate important risk factors associated with neurodegenerative conditions, specifically age and sex. In this review, we survey current literature that examines age and sex as contributing factors to head trauma-mediated neurodegeneration in humans and preclinical models, including mammalian and Drosophila models. We discuss similarities and disparities between human and fly in aging, sex differences, and pathophysiology. Finally, we highlight Drosophila as an effective tool for investigating mechanisms underlying head trauma-induced neurodegeneration and for identifying therapeutic targets for treatment and recovery.
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Affiliation(s)
- Changtian Ye
- Department of Cell Biology, Emory University School of Medicine, Atlanta, GA, United States
| | - Joseph A. Behnke
- Department of Cell Biology, Emory University School of Medicine, Atlanta, GA, United States
| | - Katherine R. Hardin
- Department of Cell Biology, Emory University School of Medicine, Atlanta, GA, United States
| | - James Q. Zheng
- Department of Cell Biology, Emory University School of Medicine, Atlanta, GA, United States
- Department of Neurology, Emory University School of Medicine, Atlanta, GA, United States
- Center for Neurodegenerative Diseases, Emory University School of Medicine, Atlanta, GA, United States
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42
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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: 6] [Impact Index Per Article: 6.0] [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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43
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Scott H, Novikov B, Ugur B, Allen B, Mertsalov I, Monagas-Valentin P, Koff M, Baas Robinson S, Aoki K, Veizaj R, Lefeber DJ, Tiemeyer M, Bellen H, Panin V. Glia-neuron coupling via a bipartite sialylation pathway promotes neural transmission and stress tolerance in Drosophila. eLife 2023; 12:e78280. [PMID: 36946697 PMCID: PMC10110239 DOI: 10.7554/elife.78280] [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: 03/01/2022] [Accepted: 03/16/2023] [Indexed: 03/23/2023] Open
Abstract
Modification by sialylated glycans can affect protein functions, underlying mechanisms that control animal development and physiology. Sialylation relies on a dedicated pathway involving evolutionarily conserved enzymes, including CMP-sialic acid synthetase (CSAS) and sialyltransferase (SiaT) that mediate the activation of sialic acid and its transfer onto glycan termini, respectively. In Drosophila, CSAS and DSiaT genes function in the nervous system, affecting neural transmission and excitability. We found that these genes function in different cells: the function of CSAS is restricted to glia, while DSiaT functions in neurons. This partition of the sialylation pathway allows for regulation of neural functions via a glia-mediated control of neural sialylation. The sialylation genes were shown to be required for tolerance to heat and oxidative stress and for maintenance of the normal level of voltage-gated sodium channels. Our results uncovered a unique bipartite sialylation pathway that mediates glia-neuron coupling and regulates neural excitability and stress tolerance.
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Affiliation(s)
- Hilary Scott
- Department of Biochemistry and Biophysics, Texas A&M UniversityCollege StationUnited States
| | - Boris Novikov
- Department of Biochemistry and Biophysics, Texas A&M UniversityCollege StationUnited States
| | - Berrak Ugur
- Departments of Molecular and Human Genetics and Neuroscience, Baylor College of Medicine, and Jan and Dan Duncan Neurological Research Institute, Texas Children’s HospitalHoustonUnited States
| | - Brooke Allen
- Department of Biochemistry and Biophysics, Texas A&M UniversityCollege StationUnited States
| | - Ilya Mertsalov
- Department of Biochemistry and Biophysics, Texas A&M UniversityCollege StationUnited States
| | - Pedro Monagas-Valentin
- Department of Biochemistry and Biophysics, Texas A&M UniversityCollege StationUnited States
| | - Melissa Koff
- Department of Biochemistry and Biophysics, Texas A&M UniversityCollege StationUnited States
| | - Sarah Baas Robinson
- Complex Carbohydrate Research Center, University of GeorgiaAthensUnited States
| | - Kazuhiro Aoki
- Complex Carbohydrate Research Center, University of GeorgiaAthensUnited States
| | - Raisa Veizaj
- Translational Metabolic Laboratory, Department of Neurology, Donders Institute for Brain, Cognition and Behavior, Radboud University Medical CenterNijmegenNetherlands
| | - Dirk J Lefeber
- Translational Metabolic Laboratory, Department of Neurology, Donders Institute for Brain, Cognition and Behavior, Radboud University Medical CenterNijmegenNetherlands
| | - Michael Tiemeyer
- Complex Carbohydrate Research Center, University of GeorgiaAthensUnited States
| | - Hugo Bellen
- Departments of Molecular and Human Genetics and Neuroscience, Baylor College of Medicine, and Jan and Dan Duncan Neurological Research Institute, Texas Children’s HospitalHoustonUnited States
| | - Vladislav Panin
- Department of Biochemistry and Biophysics, Texas A&M UniversityCollege StationUnited States
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Fabian B, Sachse S. Experience-dependent plasticity in the olfactory system of Drosophila melanogaster and other insects. Front Cell Neurosci 2023; 17:1130091. [PMID: 36923450 PMCID: PMC10010147 DOI: 10.3389/fncel.2023.1130091] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2022] [Accepted: 02/07/2023] [Indexed: 02/24/2023] Open
Abstract
It is long known that the nervous system of vertebrates can be shaped by internal and external factors. On the other hand, the nervous system of insects was long assumed to be stereotypic, although evidence for plasticity effects accumulated for several decades. To cover the topic comprehensively, this review recapitulates the establishment of the term "plasticity" in neuroscience and introduces its original meaning. We describe the basic composition of the insect olfactory system using Drosophila melanogaster as a representative example and outline experience-dependent plasticity effects observed in this part of the brain in a variety of insects, including hymenopterans, lepidopterans, locusts, and flies. In particular, we highlight recent advances in the study of experience-dependent plasticity effects in the olfactory system of D. melanogaster, as it is the most accessible olfactory system of all insect species due to the genetic tools available. The partly contradictory results demonstrate that morphological, physiological and behavioral changes in response to long-term olfactory stimulation are more complex than previously thought. Different molecular mechanisms leading to these changes were unveiled in the past and are likely responsible for this complexity. We discuss common problems in the study of experience-dependent plasticity, ways to overcome them, and future directions in this area of research. In addition, we critically examine the transferability of laboratory data to natural systems to address the topic as holistically as possible. As a mechanism that allows organisms to adapt to new environmental conditions, experience-dependent plasticity contributes to an animal's resilience and is therefore a crucial topic for future research, especially in an era of rapid environmental changes.
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Affiliation(s)
| | - Silke Sachse
- Research Group Olfactory Coding, Max Planck Institute for Chemical Ecology, Jena, Germany
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45
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Endogenous retroviruses and TDP-43 proteinopathy form a sustaining feedback driving intercellular spread of Drosophila neurodegeneration. Nat Commun 2023; 14:966. [PMID: 36810738 PMCID: PMC9944888 DOI: 10.1038/s41467-023-36649-z] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2022] [Accepted: 02/09/2023] [Indexed: 02/23/2023] Open
Abstract
Inter-cellular movement of "prion-like" proteins is thought to explain propagation of neurodegeneration between cells. For example, propagation of abnormally phosphorylated cytoplasmic inclusions of TAR-DNA-Binding protein (TDP-43) is proposed to underlie progression of amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD). But unlike transmissible prion diseases, ALS and FTD are not infectious and injection of aggregated TDP-43 is not sufficient to cause disease. This suggests a missing component of a positive feedback necessary to sustain disease progression. We demonstrate that endogenous retrovirus (ERV) expression and TDP-43 proteinopathy are mutually reinforcing. Expression of either Drosophila mdg4-ERV (gypsy) or the human ERV, HERV-K (HML-2) are each sufficient to stimulate cytoplasmic aggregation of human TDP-43. Viral ERV transmission also triggers TDP-43 pathology in recipient cells that express physiological levels of TDP-43, whether they are in contact or at a distance. This mechanism potentially underlies the TDP-43 proteinopathy-caused neurodegenerative propagation through neuronal tissue.
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46
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Bhasiin K, Heintz O, Colodner KJ. Optimization and Technical Considerations for the Dye-Exclusion Protocol Used to Assess Blood-Brain Barrier Integrity in Adult Drosophila melanogaster. Int J Mol Sci 2023; 24:ijms24031886. [PMID: 36768206 PMCID: PMC9916281 DOI: 10.3390/ijms24031886] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2022] [Revised: 01/05/2023] [Accepted: 01/11/2023] [Indexed: 01/21/2023] Open
Abstract
The blood-brain barrier (BBB) is a multicellular construct that regulates the diffusion and transport of metabolites, ions, toxins, and inflammatory mediators into and out of the central nervous system (CNS). Its integrity is essential for proper brain physiology, and its breakdown has been shown to contribute to neurological dysfunction. The BBB in vertebrates exists primarily through the coordination between endothelial cells, pericytes, and astrocytes, while invertebrates, which lack a vascularized circulatory system, typically have a barrier composed of glial cells that separate the CNS from humoral fluids. Notably, the invertebrate barrier is molecularly and functionally analogous to the vertebrate BBB, and the fruit fly, Drosophila melanogaster, is increasingly recognized as a useful model system in which to investigate barrier function. The most widely used technique to assess barrier function in the fly is the dye-exclusion assay, which involves monitoring the infiltration of a fluorescent-coupled dextran into the brain. In this study, we explore analytical and technical considerations of this procedure that yield a more reliable assessment of barrier function, and we validate our findings using a traumatic injury model. Together, we have identified parameters that optimize the dye-exclusion assay and provide an alternative framework for future studies examining barrier function in Drosophila.
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47
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SIK3 and Wnk converge on Fray to regulate glial K+ buffering and seizure susceptibility. PLoS Genet 2023; 19:e1010581. [PMID: 36626385 PMCID: PMC9870106 DOI: 10.1371/journal.pgen.1010581] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2022] [Revised: 01/23/2023] [Accepted: 12/19/2022] [Indexed: 01/11/2023] Open
Abstract
Glial cells play a critical role in maintaining homeostatic ion concentration gradients. Salt-inducible kinase 3 (SIK3) regulates a gene expression program that controls K+ buffering in glia, and upregulation of this pathway suppresses seizure behavior in the eag, Shaker hyperexcitability mutant. Here we show that boosting the glial SIK3 K+ buffering pathway suppresses seizures in three additional molecularly diverse hyperexcitable mutants, highlighting the therapeutic potential of upregulating glial K+ buffering. We then explore additional mechanisms regulating glial K+ buffering. Fray, a transcriptional target of the SIK3 K+ buffering program, is a kinase that promotes K+ uptake by activating the Na+/K+/Cl- co-transporter, Ncc69. We show that the Wnk kinase phosphorylates Fray in Drosophila glia and that this activity is required to promote K+ buffering. This identifies Fray as a convergence point between the SIK3-dependent transcriptional program and Wnk-dependent post-translational regulation. Bypassing both regulatory mechanisms via overexpression of a constitutively active Fray in glia is sufficient to robustly suppress seizure behavior in multiple Drosophila models of hyperexcitability. Finally, we identify cortex glia as a critical cell type for regulation of seizure susceptibility, as boosting K+ buffering via expression of activated Fray exclusively in these cells is sufficient to suppress seizure behavior. These findings highlight Fray as a key convergence point for distinct K+ buffering regulatory mechanisms and cortex glia as an important locus for control of neuronal excitability.
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48
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De Lazzari F, Agostini F, Plotegher N, Sandre M, Greggio E, Megighian A, Bubacco L, Sandrelli F, Whitworth AJ, Bisaglia M. DJ-1 promotes energy balance by regulating both mitochondrial and autophagic homeostasis. Neurobiol Dis 2023; 176:105941. [PMID: 36473592 DOI: 10.1016/j.nbd.2022.105941] [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: 10/21/2022] [Revised: 11/23/2022] [Accepted: 12/02/2022] [Indexed: 12/12/2022] Open
Abstract
The protein DJ-1 is mutated in rare familial forms of recessive Parkinson's disease and in parkinsonism accompanied by amyotrophic lateral sclerosis symptoms and dementia. DJ-1 is considered a multitasking protein able to confer protection under various conditions of stress. However, the precise cellular function still remains elusive. In the present work, we evaluated fruit flies lacking the expression of the DJ-1 homolog dj-1β as compared to control aged-matched individuals. Behavioral evaluations included lifespan, locomotion in an open field arena, sensitivity to oxidative insults, and resistance to starvation. Molecular analyses were carried out by analyzing the mitochondrial morphology and functionality, and the autophagic response. We demonstrated that dj-1β null mutant flies are hypoactive and display higher sensitivity to oxidative insults and food deprivation. Analysis of mitochondrial homeostasis revealed that loss of dj-1β leads to larger and more circular mitochondria, characterized by impaired complex-I-linked respiration while preserving ATP production capacity. Additionally, dj-1β null mutant flies present an impaired autophagic response, which is suppressed by treatment with the antioxidant molecule N-Acetyl-L-Cysteine. Overall, our data point to a mechanism whereby DJ-1 plays a critical role in the maintenance of energy homeostasis, by sustaining mitochondrial homeostasis and affecting the autophagic flux through the maintenance of the cellular redox state. In light of the involvement of DJ-1 in neurodegenerative diseases and considering that neurons are highly energy-demanding cells, particularly sensitive to redox stress, our study sheds light on a key role of DJ-1 in the maintenance of cellular homeostasis.
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Affiliation(s)
- Federica De Lazzari
- Department of Biology, University of Padua, Padua 35121, Italy; Medical Research Council Mitochondrial Biology Unit, University of Cambridge, Cambridge Biomedical Campus, Cambridge CB2 0XY, UK.
| | | | | | - Michele Sandre
- Department of Neuroscience, University of Padua, Padua 35121, Italy.
| | - Elisa Greggio
- Department of Biology, University of Padua, Padua 35121, Italy; Study Center for Neurodegeneration (CESNE), Padua 35121, Italy.
| | - Aram Megighian
- Department of Biomedical Sciences, University of Padua, Padua 35121, Italy.
| | - Luigi Bubacco
- Department of Biology, University of Padua, Padua 35121, Italy; Study Center for Neurodegeneration (CESNE), Padua 35121, Italy.
| | | | - Alexander J Whitworth
- Medical Research Council Mitochondrial Biology Unit, University of Cambridge, Cambridge Biomedical Campus, Cambridge CB2 0XY, UK.
| | - Marco Bisaglia
- Department of Biology, University of Padua, Padua 35121, Italy; Study Center for Neurodegeneration (CESNE), Padua 35121, Italy.
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49
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Wang H, Xie Y, Wang X, Geng X, Gao L. Characterization of the RACK1 gene of Aips cerana cerana and its role in adverse environmental stresses. Comp Biochem Physiol B Biochem Mol Biol 2023; 263:110796. [PMID: 35973656 DOI: 10.1016/j.cbpb.2022.110796] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2022] [Revised: 08/05/2022] [Accepted: 08/10/2022] [Indexed: 11/23/2022]
Abstract
Receptors for Activated C Kinase 1 (RACK1s) are a kind of multifunction scaffold protein that plays an important role in cell signal transductions and animal development. However, the function of RACK1 in the Chinese honeybee Apis cerana cerana is little known. Here, we isolated and identified a RACK1 gene from Apis cerana cerana, named AccRACK1. By bioinformatic analysis, we revealed a high nucleic acid homology between AccRACK1 and RACK1 of Apis cerana. RT-qPCR analyses demonstrated AccRACK1 was mostly expressed in 3rd instar larvae, darked-eyed pupae and adults (one and thirty days post-emergence), suggesting it might participate in the development of A. cerana cerana. Moreover, the expression of AccRACK1 was highest in the thorax, followed by the venom gland. Compared to the blank control group, AccRACK1 was induced by 24 and 44 °C, HgCl2 and pesticides (paraquat, pyridaben and methomyl) but inhibited by 14 °C, H2O2, UV light and cyhalothrin. Additionally, 0.05, 0.1, 1, 5 and 10 mg/ml PPN (juvenile hormone analogue pyriproxyfen) could promote the expression of AccRACK1, with 1 mg/ml showing the highest upregulation, suggesting it was regulated by hormones. Further study found that after knockdown of AccRACK1 by RNAi, the expression of the eukaryotic initiation factor 6 of A. cerana cerana (AcceIF6), an initiation factor regulating the initiation of translation, was inhibited, indicating AccRACK1 might affect cellular responses by translation. These findings, taken together, suggest AccRACK1 is involved in the development and responses to abiotic stresses of A. cerana cerana, and therefore, it may be of critical importance to the survival of A. cerana cerana.
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Affiliation(s)
- Hongfei Wang
- College of Life Sciences, Shandong First Medical University & Shandong Academy of Medical Sciences, Taian, Shandong, China
| | - Yucai Xie
- College of Life Sciences, Shandong First Medical University & Shandong Academy of Medical Sciences, Taian, Shandong, China
| | - Xiaoqing Wang
- College of Life Sciences, Shandong First Medical University & Shandong Academy of Medical Sciences, Taian, Shandong, China
| | - Xiaoshan Geng
- College of Life Sciences, Shandong First Medical University & Shandong Academy of Medical Sciences, Taian, Shandong, China
| | - Lijun Gao
- College of Life Sciences, Shandong First Medical University & Shandong Academy of Medical Sciences, Taian, Shandong, China.
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50
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Calvin-Cejudo L, Martin F, Mendez LR, Coya R, Castañeda-Sampedro A, Gomez-Diaz C, Alcorta E. Neuron-glia interaction at the receptor level affects olfactory perception in adult Drosophila. iScience 2022; 26:105837. [PMID: 36624835 PMCID: PMC9823236 DOI: 10.1016/j.isci.2022.105837] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2022] [Revised: 11/17/2022] [Accepted: 12/16/2022] [Indexed: 12/23/2022] Open
Abstract
Some types of glia play an active role in neuronal signaling by modifying their activity although little is known about their role in sensory information signaling at the receptor level. In this research, we report a functional role for the glia that surround the soma of the olfactory receptor neurons (OSNs) in adult Drosophila. Specific genetic modifications have been targeted to this cell type to obtain live individuals who are tested for olfactory preference and display changes both increasing and reducing sensitivity. A closer look at the antenna by Ca2+ imaging shows that odor activates the OSNs, which subsequently produce an opposite and smaller effect in the glia that partially counterbalances neuronal activation. Therefore, these glia may play a dual role in preventing excessive activation of the OSNs at high odorant concentrations and tuning the chemosensory window for the individual according to the network structure in the receptor organ.
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Affiliation(s)
- Laura Calvin-Cejudo
- Group of Neurobiology of the Sensory Systems (NEUROSEN), Department of Functional Biology, Faculty of Medicine, University of Oviedo, 33006 Oviedo, Spain
| | - Fernando Martin
- Group of Neurobiology of the Sensory Systems (NEUROSEN), Department of Functional Biology, Faculty of Medicine, University of Oviedo, 33006 Oviedo, Spain
| | - Luis R. Mendez
- Group of Neurobiology of the Sensory Systems (NEUROSEN), Department of Functional Biology, Faculty of Medicine, University of Oviedo, 33006 Oviedo, Spain
| | - Ruth Coya
- Group of Neurobiology of the Sensory Systems (NEUROSEN), Department of Functional Biology, Faculty of Medicine, University of Oviedo, 33006 Oviedo, Spain
| | - Ana Castañeda-Sampedro
- Group of Neurobiology of the Sensory Systems (NEUROSEN), Department of Functional Biology, Faculty of Medicine, University of Oviedo, 33006 Oviedo, Spain
| | - Carolina Gomez-Diaz
- Group of Neurobiology of the Sensory Systems (NEUROSEN), Department of Functional Biology, Faculty of Medicine, University of Oviedo, 33006 Oviedo, Spain
| | - Esther Alcorta
- Group of Neurobiology of the Sensory Systems (NEUROSEN), Department of Functional Biology, Faculty of Medicine, University of Oviedo, 33006 Oviedo, Spain
- Corresponding author
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