1
|
Metcalf MG, Monshietehadi S, Sahay A, Durieux J, Frakes AE, Velichkovska M, Mena C, Farinas A, Sanchez M, Dillin A. Cell non-autonomous control of autophagy and metabolism by glial cells. iScience 2024; 27:109354. [PMID: 38500817 PMCID: PMC10946330 DOI: 10.1016/j.isci.2024.109354] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2022] [Revised: 11/01/2023] [Accepted: 02/23/2024] [Indexed: 03/20/2024] Open
Abstract
Glia are the protectors of the nervous system, providing neurons with support and protection from cytotoxic insults. We previously discovered that four astrocyte-like glia can regulate organismal proteostasis and longevity in C. elegans. Expression of the UPRER transcription factor, XBP-1s, in these glia increases stress resistance, and longevity, and activates the UPRER in intestinal cells via neuropeptides. Autophagy, a key regulator of metabolism and aging, has been described as a cell autonomous process. Surprisingly, we find that glial XBP-1s enhances proteostasis and longevity by cell non-autonomously reprogramming organismal lipid metabolism and activating autophagy. Glial XBP-1s regulates the activation of another transcription factor, HLH-30/TFEB, in the intestine. HLH-30 activates intestinal autophagy, increases intestinal lipid catabolism, and upregulates a robust transcriptional program. Our study reveals a novel role for glia in regulating peripheral lipid metabolism, autophagy, and organellar health through peripheral activation of HLH-30 and autophagy.
Collapse
Affiliation(s)
- Melissa G. Metcalf
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, CA 94720, USA
- Howard Hughes Medical Institute, University of California, Berkeley, Berkeley, CA 94720, USA
| | - Samira Monshietehadi
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, CA 94720, USA
- Howard Hughes Medical Institute, University of California, Berkeley, Berkeley, CA 94720, USA
| | - Arushi Sahay
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, CA 94720, USA
- Howard Hughes Medical Institute, University of California, Berkeley, Berkeley, CA 94720, USA
| | - Jenni Durieux
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, CA 94720, USA
- Howard Hughes Medical Institute, University of California, Berkeley, Berkeley, CA 94720, USA
| | - Ashley E. Frakes
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, CA 94720, USA
- Howard Hughes Medical Institute, University of California, Berkeley, Berkeley, CA 94720, USA
| | - Martina Velichkovska
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, CA 94720, USA
- Howard Hughes Medical Institute, University of California, Berkeley, Berkeley, CA 94720, USA
| | - Cesar Mena
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, CA 94720, USA
- Howard Hughes Medical Institute, University of California, Berkeley, Berkeley, CA 94720, USA
| | - Amelia Farinas
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, CA 94720, USA
- Howard Hughes Medical Institute, University of California, Berkeley, Berkeley, CA 94720, USA
| | - Melissa Sanchez
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, CA 94720, USA
- Howard Hughes Medical Institute, University of California, Berkeley, Berkeley, CA 94720, USA
| | - Andrew Dillin
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, CA 94720, USA
- Howard Hughes Medical Institute, University of California, Berkeley, Berkeley, CA 94720, USA
| |
Collapse
|
2
|
Coraggio F, Bhushan M, Roumeliotis S, Caroti F, Bevilacqua C, Prevedel R, Rapti G. Age-progressive interplay of HSP-proteostasis, ECM-cell junctions and biomechanics ensures C. elegans astroglial architecture. Nat Commun 2024; 15:2861. [PMID: 38570505 PMCID: PMC10991496 DOI: 10.1038/s41467-024-46827-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2023] [Accepted: 03/12/2024] [Indexed: 04/05/2024] Open
Abstract
Tissue integrity is sensitive to temperature, tension, age, and is sustained throughout life by adaptive cell-autonomous or extrinsic mechanisms. Safeguarding the remarkably-complex architectures of neurons and glia ensures age-dependent integrity of functional circuits. Here, we report mechanisms sustaining the integrity of C. elegans CEPsh astrocyte-like glia. We combine large-scale genetics with manipulation of genes, cells, and their environment, quantitative imaging of cellular/ subcellular features, tissue material properties and extracellular matrix (ECM). We identify mutants with age-progressive, environment-dependent defects in glial architecture, consequent disruption of neuronal architecture, and abnormal aging. Functional loss of epithelial Hsp70/Hsc70-cochaperone BAG2 causes ECM disruption, altered tissue biomechanics, and hypersensitivity of glia to environmental temperature and mechanics. Glial-cell junctions ensure epithelia-ECM-CEPsh glia association. Modifying glial junctions or ECM mechanics safeguards glial integrity against disrupted BAG2-proteostasis. Overall, we present a finely-regulated interplay of proteostasis-ECM and cell junctions with conserved components that ensures age-progressive robustness of glial architecture.
Collapse
Affiliation(s)
- Francesca Coraggio
- Developmental Biology Unit, European Molecular Biology Laboratory, Heidelberg, Germany
| | - Mahak Bhushan
- Developmental Biology Unit, European Molecular Biology Laboratory, Heidelberg, Germany
| | - Spyridon Roumeliotis
- Developmental Biology Unit, European Molecular Biology Laboratory, Heidelberg, Germany
| | - Francesca Caroti
- Developmental Biology Unit, European Molecular Biology Laboratory, Heidelberg, Germany
| | - Carlo Bevilacqua
- Cell Biology and Biophysics Unit, European Molecular Biology Laboratory, Heidelberg, Germany
| | - Robert Prevedel
- Developmental Biology Unit, European Molecular Biology Laboratory, Heidelberg, Germany
- Cell Biology and Biophysics Unit, European Molecular Biology Laboratory, Heidelberg, Germany
- Epigenetics and Neurobiology Unit, European Molecular Biology Laboratory, Rome, Italy
- Interdisciplinary Center of Neurosciences, Heidelberg University, Heidelberg, Germany
- German Center for Lung Research (DZL), Heidelberg, Germany
| | - Georgia Rapti
- Developmental Biology Unit, European Molecular Biology Laboratory, Heidelberg, Germany.
- Epigenetics and Neurobiology Unit, European Molecular Biology Laboratory, Rome, Italy.
- Interdisciplinary Center of Neurosciences, Heidelberg University, Heidelberg, Germany.
| |
Collapse
|
3
|
Xu W, Liu J, Qi H, Si R, Zhao Z, Tao Z, Bai Y, Hu S, Sun X, Cong Y, Zhang H, Fan D, Xiao L, Wang Y, Li Y, Du Z. A lineage-resolved cartography of microRNA promoter activity in C. elegans empowers multidimensional developmental analysis. Nat Commun 2024; 15:2783. [PMID: 38555276 PMCID: PMC10981687 DOI: 10.1038/s41467-024-47055-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2024] [Accepted: 03/13/2024] [Indexed: 04/02/2024] Open
Abstract
Elucidating the expression of microRNAs in developing single cells is critical for functional discovery. Here, we construct scCAMERA (single-cell cartography of microRNA expression based on reporter assay), utilizing promoter-driven fluorescent reporters in conjunction with imaging and lineage tracing. The cartography delineates the transcriptional activity of 54 conserved microRNAs in lineage-resolved single cells throughout C. elegans embryogenesis. The combinatorial expression of microRNAs partitions cells into fine clusters reflecting their function and anatomy. Notably, the expression of individual microRNAs exhibits high cell specificity and divergence among family members. Guided by cellular expression patterns, we identify developmental functions of specific microRNAs, including miR-1 in pharynx development and physiology, miR-232 in excretory canal morphogenesis by repressing NHR-25/NR5A, and a functional synergy between miR-232 and miR-234 in canal development, demonstrating the broad utility of scCAMERA. Furthermore, integrative analysis reveals that tissue-specific fate determinants activate microRNAs to repress protein production from leaky transcripts associated with alternative, especially neuronal, fates, thereby enhancing the fidelity of developmental fate differentiation. Collectively, our study offers rich opportunities for multidimensional expression-informed analysis of microRNA biology in metazoans.
Collapse
Affiliation(s)
- Weina Xu
- State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Jinyi Liu
- State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Huan Qi
- State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, China
| | - Ruolin Si
- College of Life Sciences, Capital Normal University, Beijing, China
| | - Zhiguang Zhao
- State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Zhiju Tao
- College of Life Sciences, Capital Normal University, Beijing, China
| | - Yuchuan Bai
- College of Life Sciences, Capital Normal University, Beijing, China
| | - Shipeng Hu
- College of Life Sciences, Capital Normal University, Beijing, China
| | - Xiaohan Sun
- State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Yulin Cong
- State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Haoye Zhang
- State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Duchangjiang Fan
- State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Long Xiao
- State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, China
| | - Yangyang Wang
- State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, China
| | - Yongbin Li
- College of Life Sciences, Capital Normal University, Beijing, China.
| | - Zhuo Du
- State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, China.
- University of Chinese Academy of Sciences, Beijing, China.
| |
Collapse
|
4
|
Yang F, Bevilacqua C, Hambura S, Neves A, Gopalan A, Watanabe K, Govendir M, Bernabeu M, Ellenberg J, Diz-Muñoz A, Köhler S, Rapti G, Jechlinger M, Prevedel R. Pulsed stimulated Brillouin microscopy enables high-sensitivity mechanical imaging of live and fragile biological specimens. Nat Methods 2023; 20:1971-1979. [PMID: 37884795 PMCID: PMC10703689 DOI: 10.1038/s41592-023-02054-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2023] [Accepted: 09/20/2023] [Indexed: 10/28/2023]
Abstract
Brillouin microscopy is an emerging optical elastography technique capable of assessing mechanical properties of biological samples in a three-dimensional, all-optical and noncontact fashion. The typically weak Brillouin scattering signal can be substantially enhanced via a stimulated Brillouin scattering (SBS) process; however, current implementations require high pump powers, which prohibit applications to photosensitive or live imaging of biological samples. Here we present a pulsed SBS scheme that takes advantage of the nonlinearity of the pump-probe interaction. In particular, we show that the required pump laser power can be decreased ~20-fold without affecting the signal levels or spectral precision. We demonstrate the low phototoxicity and high specificity of our pulsed SBS approach by imaging, with subcellular detail, sensitive single cells, zebrafish larvae, mouse embryos and adult Caenorhabditis elegans. Furthermore, our method permits observing the mechanics of organoids and C. elegans embryos over time, opening up further possibilities for the field of mechanobiology.
Collapse
Affiliation(s)
- Fan Yang
- Cell Biology and Biophysics Unit, European Molecular Biology Laboratory, Heidelberg, Germany.
- Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai, China.
| | - Carlo Bevilacqua
- Cell Biology and Biophysics Unit, European Molecular Biology Laboratory, Heidelberg, Germany
- Collaboration for joint PhD degree between EMBL and Heidelberg University, Faculty of Biosciences, Heidelberg, Germany
| | - Sebastian Hambura
- Cell Biology and Biophysics Unit, European Molecular Biology Laboratory, Heidelberg, Germany
| | - Ana Neves
- Cell Biology and Biophysics Unit, European Molecular Biology Laboratory, Heidelberg, Germany
- Collaboration for joint PhD degree between EMBL and Heidelberg University, Faculty of Biosciences, Heidelberg, Germany
| | - Anusha Gopalan
- Cell Biology and Biophysics Unit, European Molecular Biology Laboratory, Heidelberg, Germany
- Collaboration for joint PhD degree between EMBL and Heidelberg University, Faculty of Biosciences, Heidelberg, Germany
| | - Koki Watanabe
- Cell Biology and Biophysics Unit, European Molecular Biology Laboratory, Heidelberg, Germany
| | - Matt Govendir
- Cell Biology and Biophysics Unit, European Molecular Biology Laboratory, Heidelberg, Germany
- European Molecular Biology Laboratory Barcelona, Barcelona, Spain
| | - Maria Bernabeu
- European Molecular Biology Laboratory Barcelona, Barcelona, Spain
| | - Jan Ellenberg
- Cell Biology and Biophysics Unit, European Molecular Biology Laboratory, Heidelberg, Germany
| | - Alba Diz-Muñoz
- Cell Biology and Biophysics Unit, European Molecular Biology Laboratory, Heidelberg, Germany
| | - Simone Köhler
- Cell Biology and Biophysics Unit, European Molecular Biology Laboratory, Heidelberg, Germany
| | - Georgia Rapti
- Developmental Biology Unit, European Molecular Biology Laboratory, Heidelberg, Germany
- Interdisciplinary Center of Neurosciences, Heidelberg University, Heidelberg, Germany
- Epigenetics and Neurobiology Unit, European Molecular Biology Laboratory, Rome, Italy
| | - Martin Jechlinger
- Cell Biology and Biophysics Unit, European Molecular Biology Laboratory, Heidelberg, Germany
- MOLIT Institute for Personalized Medicine gGmbH, Heilbronn, Germany
| | - Robert Prevedel
- Cell Biology and Biophysics Unit, European Molecular Biology Laboratory, Heidelberg, Germany.
- Developmental Biology Unit, European Molecular Biology Laboratory, Heidelberg, Germany.
- Interdisciplinary Center of Neurosciences, Heidelberg University, Heidelberg, Germany.
- Epigenetics and Neurobiology Unit, European Molecular Biology Laboratory, Rome, Italy.
- Molecular Medicine Partnership Unit, European Molecular Biology Laboratory, Heidelberg, Germany.
- German Center for Lung Research (DZL), Heidelberg, Germany.
| |
Collapse
|
5
|
Guo M, Wu Y, Su Y, Qian S, Krueger E, Christensen R, Kroeschell G, Bui J, Chaw M, Zhang L, Liu J, Hou X, Han X, Ma X, Zhovmer A, Combs C, Moyle M, Yemini E, Liu H, Liu Z, La Riviere P, Colón-Ramos D, Shroff H. Deep learning-based aberration compensation improves contrast and resolution in fluorescence microscopy. bioRxiv 2023:2023.10.15.562439. [PMID: 37986950 PMCID: PMC10659418 DOI: 10.1101/2023.10.15.562439] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2023]
Abstract
Optical aberrations hinder fluorescence microscopy of thick samples, reducing image signal, contrast, and resolution. Here we introduce a deep learning-based strategy for aberration compensation, improving image quality without slowing image acquisition, applying additional dose, or introducing more optics into the imaging path. Our method (i) introduces synthetic aberrations to images acquired on the shallow side of image stacks, making them resemble those acquired deeper into the volume and (ii) trains neural networks to reverse the effect of these aberrations. We use simulations to show that applying the trained 'de-aberration' networks outperforms alternative methods, and subsequently apply the networks to diverse datasets captured with confocal, light-sheet, multi-photon, and super-resolution microscopy. In all cases, the improved quality of the restored data facilitates qualitative image inspection and improves downstream image quantitation, including orientational analysis of blood vessels in mouse tissue and improved membrane and nuclear segmentation in C. elegans embryos.
Collapse
Affiliation(s)
- Min Guo
- Current address: State Key Laboratory of Modern Optical Instrumentation, College of Optical Science and Engineering, Zhejiang University, Hangzhou, China
- Laboratory of High Resolution Optical Imaging, National Institute of Biomedical Imaging and Bioengineering, National Institutes of Health, Bethesda, Maryland, USA
| | - Yicong Wu
- Laboratory of High Resolution Optical Imaging, National Institute of Biomedical Imaging and Bioengineering, National Institutes of Health, Bethesda, Maryland, USA
- Advanced Imaging and Microscopy Resource, National Institutes of Health, Bethesda, Maryland, USA
| | - Yijun Su
- Laboratory of High Resolution Optical Imaging, National Institute of Biomedical Imaging and Bioengineering, National Institutes of Health, Bethesda, Maryland, USA
- Advanced Imaging and Microscopy Resource, National Institutes of Health, Bethesda, Maryland, USA
| | - Shuhao Qian
- Current address: State Key Laboratory of Modern Optical Instrumentation, College of Optical Science and Engineering, Zhejiang University, Hangzhou, China
| | - Eric Krueger
- Laboratory of High Resolution Optical Imaging, National Institute of Biomedical Imaging and Bioengineering, National Institutes of Health, Bethesda, Maryland, USA
| | - Ryan Christensen
- Laboratory of High Resolution Optical Imaging, National Institute of Biomedical Imaging and Bioengineering, National Institutes of Health, Bethesda, Maryland, USA
| | - Grant Kroeschell
- Laboratory of High Resolution Optical Imaging, National Institute of Biomedical Imaging and Bioengineering, National Institutes of Health, Bethesda, Maryland, USA
| | - Johnny Bui
- Laboratory of High Resolution Optical Imaging, National Institute of Biomedical Imaging and Bioengineering, National Institutes of Health, Bethesda, Maryland, USA
| | - Matthew Chaw
- Laboratory of High Resolution Optical Imaging, National Institute of Biomedical Imaging and Bioengineering, National Institutes of Health, Bethesda, Maryland, USA
| | - Lixia Zhang
- Advanced Imaging and Microscopy Resource, National Institutes of Health, Bethesda, Maryland, USA
| | - Jiamin Liu
- Advanced Imaging and Microscopy Resource, National Institutes of Health, Bethesda, Maryland, USA
| | - Xuekai Hou
- Current address: State Key Laboratory of Modern Optical Instrumentation, College of Optical Science and Engineering, Zhejiang University, Hangzhou, China
| | - Xiaofei Han
- Laboratory of High Resolution Optical Imaging, National Institute of Biomedical Imaging and Bioengineering, National Institutes of Health, Bethesda, Maryland, USA
| | - Xuefei Ma
- Center for Biologics Evaluation and Research, U.S. Food and Drug Administration, Silver Spring, MD, USA
| | - Alexander Zhovmer
- Center for Biologics Evaluation and Research, U.S. Food and Drug Administration, Silver Spring, MD, USA
| | - Christian Combs
- NHLBI Light Microscopy Facility, National Institutes of Health, Bethesda, MD, USA
| | - Mark Moyle
- Department of Biology, Brigham Young University-Idaho, Rexburg, ID, USA
| | - Eviatar Yemini
- Department of Neurobiology, UMass Chan Medical School, Worcester, MA
| | - Huafeng Liu
- Current address: State Key Laboratory of Modern Optical Instrumentation, College of Optical Science and Engineering, Zhejiang University, Hangzhou, China
| | - Zhiyi Liu
- Current address: State Key Laboratory of Modern Optical Instrumentation, College of Optical Science and Engineering, Zhejiang University, Hangzhou, China
| | - Patrick La Riviere
- Department of Radiology, University of Chicago, Chicago, IL, USA
- MBL Fellows Program, Marine Biological Laboratory, Woods Hole, MA, USA
| | - Daniel Colón-Ramos
- MBL Fellows Program, Marine Biological Laboratory, Woods Hole, MA, USA
- Wu Tsai Institute, Department of Neuroscience and Department of Cell Biology, Yale University School of Medicine, New Haven, CT, USA
| | - Hari Shroff
- Laboratory of High Resolution Optical Imaging, National Institute of Biomedical Imaging and Bioengineering, National Institutes of Health, Bethesda, Maryland, USA
- Advanced Imaging and Microscopy Resource, National Institutes of Health, Bethesda, Maryland, USA
- MBL Fellows Program, Marine Biological Laboratory, Woods Hole, MA, USA
| |
Collapse
|
6
|
Rapti G. Regulation of axon pathfinding by astroglia across genetic model organisms. Front Cell Neurosci 2023; 17:1241957. [PMID: 37941606 PMCID: PMC10628440 DOI: 10.3389/fncel.2023.1241957] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2023] [Accepted: 09/07/2023] [Indexed: 11/10/2023] Open
Abstract
Glia and neurons are intimately associated throughout bilaterian nervous systems, and were early proposed to interact for patterning circuit assembly. The investigations of circuit formation progressed from early hypotheses of intermediate guideposts and a "glia blueprint", to recent genetic and cell manipulations, and visualizations in vivo. An array of molecular factors are implicated in axon pathfinding but their number appears small relatively to circuit complexity. Comprehending this circuit complexity requires to identify unknown factors and dissect molecular topographies. Glia contribute to both aspects and certain studies provide molecular and functional insights into these contributions. Here, I survey glial roles in guiding axon navigation in vivo, emphasizing analogies, differences and open questions across major genetic models. I highlight studies pioneering the topic, and dissect recent findings that further advance our current molecular understanding. Circuits of the vertebrate forebrain, visual system and neural tube in zebrafish, mouse and chick, the Drosophila ventral cord and the C. elegans brain-like neuropil emerge as major contexts to study glial cell functions in axon navigation. I present astroglial cell types in these models, and their molecular and cellular interactions that drive axon guidance. I underline shared principles across models, conceptual or technical complications, and open questions that await investigation. Glia of the radial-astrocyte lineage, emerge as regulators of axon pathfinding, often employing common molecular factors across models. Yet this survey also highlights different involvements of glia in embryonic navigation or pioneer axon pathfinding, and unknowns in the molecular underpinnings of glial cell functions. Future cellular and molecular investigations should complete the comprehensive view of glial roles in circuit assembly.
Collapse
Affiliation(s)
- Georgia Rapti
- Developmental Biology Unit, European Molecular Biology Laboratory, Heidelberg, Germany
- Epigenetics and Neurobiology Unit, European Molecular Biology Laboratory, Rome, Italy
- Interdisciplinary Center of Neurosciences, Heidelberg University, Heidelberg, Germany
| |
Collapse
|
7
|
Chandra B, Voas MG, Davies EL, Roberts-Galbraith RH. Ets-1 transcription factor regulates glial cell regeneration and function in planarians. Development 2023; 150:dev201666. [PMID: 37665145 PMCID: PMC10508700 DOI: 10.1242/dev.201666] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2023] [Accepted: 08/15/2023] [Indexed: 09/05/2023]
Abstract
Glia play multifaceted roles in nervous systems in response to injury. Depending on the species, extent of injury and glial cell type in question, glia can help or hinder the regeneration of neurons. Studying glia in the context of successful regeneration could reveal features of pro-regenerative glia that could be exploited for new human therapies. Planarian flatworms completely regenerate their nervous systems after injury - including glia - and thus provide a strong model system for exploring glia in the context of regeneration. Here, we report that planarian glia regenerate after neurons, and that neurons are required for correct glial numbers and localization during regeneration. We also identify the planarian transcription factor-encoding gene ets-1 as a key regulator of glial cell maintenance and regeneration. Using ets-1 (RNAi) to perturb glia, we show that glial loss is associated with altered neuronal gene expression, impeded animal movement and impaired nervous system architecture - particularly within the neuropil. Importantly, our work reveals the inter-relationships of glia and neurons in the context of robust neural regeneration.
Collapse
Affiliation(s)
- Bidushi Chandra
- Department of Cellular Biology, University of Georgia, Athens, GA 30602, USA
| | - Matthew G. Voas
- Center for Cancer Research, National Cancer Institute, National Institutes of Health, Frederick, MD 21702, USA
| | - Erin L. Davies
- Center for Cancer Research, National Cancer Institute, National Institutes of Health, Frederick, MD 21702, USA
| | | |
Collapse
|
8
|
Santella A, Kolotuev I, Kizilyaprak C, Bao Z. Cross-modality synthesis of EM time series and live fluorescence imaging. eLife 2022; 11:77918. [PMID: 35666127 PMCID: PMC9213002 DOI: 10.7554/elife.77918] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2022] [Accepted: 06/05/2022] [Indexed: 11/13/2022] Open
Abstract
Analyses across imaging modalities allow the integration of complementary spatiotemporal information about brain development, structure, and function. However, systematic atlasing across modalities is limited by challenges to effective image alignment. We combine highly spatially resolved electron microscopy (EM) and highly temporally resolved time-lapse fluorescence microscopy (FM) to examine the emergence of a complex nervous system in Caenorhabditis elegans embryogenesis. We generate an EM time series at four classic developmental stages and create a landmark-based co-optimization algorithm for cross-modality image alignment, which handles developmental heterochrony among datasets to achieve accurate single-cell level alignment. Synthesis based on the EM series and time-lapse FM series carrying different cell-specific markers reveals critical dynamic behaviors across scales of identifiable individual cells in the emergence of the primary neuropil, the nerve ring, as well as a major sensory organ, the amphid. Our study paves the way for systematic cross-modality data synthesis in C. elegans and demonstrates a powerful approach that may be applied broadly.
Collapse
Affiliation(s)
- Anthony Santella
- Molecular Cytology Core, Memorial Sloan Kettering Cancer Center, New York, United States
| | - Irina Kolotuev
- Electron Microscopy Facility, University of Lausanne, Lausanne, Switzerland
| | | | - Zhirong Bao
- Developmental Biology Program, Memorial Sloan Kettering Cancer Center, New York, United States
| |
Collapse
|
9
|
Rapti G. Open Frontiers in Neural Cell Type Investigations; Lessons From Caenorhabditis elegans and Beyond, Toward a Multimodal Integration. Front Neurosci 2022; 15:787753. [PMID: 35321480 PMCID: PMC8934944 DOI: 10.3389/fnins.2021.787753] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2021] [Accepted: 12/30/2021] [Indexed: 11/13/2022] Open
Abstract
Nervous system cells, the building blocks of circuits, have been studied with ever-progressing resolution, yet neural circuits appear still resistant to schemes of reductionist classification. Due to their sheer numbers, complexity and diversity, their systematic study requires concrete classifications that can serve reduced dimensionality, reproducibility, and information integration. Conventional hierarchical schemes transformed through the history of neuroscience by prioritizing criteria of morphology, (electro)physiological activity, molecular content, and circuit function, influenced by prevailing methodologies of the time. Since the molecular biology revolution and the recent advents in transcriptomics, molecular profiling gains ground toward the classification of neurons and glial cell types. Yet, transcriptomics entails technical challenges and more importantly uncovers unforeseen spatiotemporal heterogeneity, in complex and simpler nervous systems. Cells change states dynamically in space and time, in response to stimuli or throughout their developmental trajectory. Mapping cell type and state heterogeneity uncovers uncharted terrains in neurons and especially in glial cell biology, that remains understudied in many aspects. Examining neurons and glial cells from the perspectives of molecular neuroscience, physiology, development and evolution highlights the advantage of multifaceted classification schemes. Among the amalgam of models contributing to neuroscience research, Caenorhabditis elegans combines nervous system anatomy, lineage, connectivity and molecular content, all mapped at single-cell resolution, and can provide valuable insights for the workflow and challenges of the multimodal integration of cell type features. This review reflects on concepts and practices of neuron and glial cells classification and how research, in C. elegans and beyond, guides nervous system experimentation through integrated multidimensional schemes. It highlights underlying principles, emerging themes, and open frontiers in the study of nervous system development, regulatory logic and evolution. It proposes unified platforms to allow integrated annotation of large-scale datasets, gene-function studies, published or unpublished findings and community feedback. Neuroscience is moving fast toward interdisciplinary, high-throughput approaches for combined mapping of the morphology, physiology, connectivity, molecular function, and the integration of information in multifaceted schemes. A closer look in mapped neural circuits and understudied terrains offers insights for the best implementation of these approaches.
Collapse
|
10
|
Juanez K, Ghose P. Repurposing the Killing Machine: Non-canonical Roles of the Cell Death Apparatus in Caenorhabditis elegans Neurons. Front Cell Dev Biol 2022; 10:825124. [PMID: 35237604 PMCID: PMC8882910 DOI: 10.3389/fcell.2022.825124] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2021] [Accepted: 01/31/2022] [Indexed: 12/29/2022] Open
Abstract
Here we highlight the increasingly divergent functions of the Caenorhabditis elegans cell elimination genes in the nervous system, beyond their well-documented roles in cell dismantling and removal. We describe relevant background on the C. elegans nervous system together with the apoptotic cell death and engulfment pathways, highlighting pioneering work in C. elegans. We discuss in detail the unexpected, atypical roles of cell elimination genes in various aspects of neuronal development, response and function. This includes the regulation of cell division, pruning, axon regeneration, and behavioral outputs. We share our outlook on expanding our thinking as to what cell elimination genes can do and noting their versatility. We speculate on the existence of novel genes downstream and upstream of the canonical cell death pathways relevant to neuronal biology. We also propose future directions emphasizing the exploration of the roles of cell death genes in pruning and guidance during embryonic development.
Collapse
|
11
|
Abstract
Following the spectacular success of molecular genetics in deciphering the genetic code in the 1960s, several of its leading practitioners felt sufficiently emboldened to use their newly acquired skills to move on and study that most enigmatic of biological organs - the brain. Sydney Brenner's approach was to focus on Caenorhabditis elegans, a nematode that is genetically tractable, has a nervous system that generates a rich repertoire of behaviours yet is small enough to allow anatomical reconstructions with ultrastructural precision. Through force of personality and some inspired pioneering studies, Brenner managed to ignite a bonfire of enthusiasm for this organism, which has resulted in its nervous system becoming the best understood of that in any organism. Initially, many were skeptical that this rather strange structure with just a few hundred neurons would yield insights that were relevant to vertebrate nervous systems. However, fifty years on we know that the basic repertoire of molecular components of worm and human nervous systems are remarkably similar. Furthermore, worms have a similar diversity of these components rather than a primitive sub-set. It appears that the fundamental difference in a vertebrate nervous system is a huge expansion of the neural units that comprise a basic brain such as that exemplified in C. elegans.
Collapse
Affiliation(s)
- John White
- Laboratory of Cell and Molecular Biology, University of Wisconsin, Madison, WI, USA
| |
Collapse
|
12
|
Abstract
The formation of the nervous system and its striking complexity is a remarkable feat of development. C. elegans served as a unique model to dissect the molecular events in neurodevelopment, from its early visionaries to the current booming neuroscience community. Soon after being introduced as a model, C. elegans was mapped at the level of genes, cells, and synapses, providing the first metazoan with a complete cell lineage, sequenced genome, and connectome. Here, I summarize mechanisms underlying C. elegans neurodevelopment, from the generation and diversification of neural components to their navigation and connectivity. I point out recent noteworthy findings in the fields of glia biology, sex dimorphism and plasticity in neurodevelopment, highlighting how current research connects back to the pioneering studies by Brenner, Sulston and colleagues. Multifaceted investigations in model organisms, connecting genes to cell function and behavior, expand our mechanistic understanding of neurodevelopment while allowing us to formulate emerging questions for future discoveries.
Collapse
Affiliation(s)
- Georgia Rapti
- European Molecular Biology Laboratory, Unit of Developmental Biology, Heidelberg, Germany
| |
Collapse
|
13
|
Takechi H, Hakeda-Suzuki S, Nitta Y, Ishiwata Y, Iwanaga R, Sato M, Sugie A, Suzuki T. Glial insulin regulates cooperative or antagonistic Golden goal/Flamingo interactions during photoreceptor axon guidance. eLife 2021; 10:66718. [PMID: 33666170 PMCID: PMC7987344 DOI: 10.7554/elife.66718] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2021] [Accepted: 03/02/2021] [Indexed: 11/29/2022] Open
Abstract
Transmembrane protein Golden goal (Gogo) interacts with atypical cadherin Flamingo (Fmi) to direct R8 photoreceptor axons in the Drosophila visual system. However, the precise mechanisms underlying Gogo regulation during columnar- and layer-specific R8 axon targeting are unknown. Our studies demonstrated that the insulin secreted from surface and cortex glia switches the phosphorylation status of Gogo, thereby regulating its two distinct functions. Non-phosphorylated Gogo mediates the initial recognition of the glial protrusion in the center of the medulla column, whereas phosphorylated Gogo suppresses radial filopodia extension by counteracting Flamingo to maintain a one axon-to-one column ratio. Later, Gogo expression ceases during the midpupal stage, thus allowing R8 filopodia to extend vertically into the M3 layer. These results demonstrate that the long- and short-range signaling between the glia and R8 axon growth cones regulates growth cone dynamics in a stepwise manner, and thus shapes the entire organization of the visual system.
Collapse
Affiliation(s)
- Hiroki Takechi
- Graduate School of Life Science and Technology, Tokyo Institute of Technology, Yokohama, Japan
| | - Satoko Hakeda-Suzuki
- Graduate School of Life Science and Technology, Tokyo Institute of Technology, Yokohama, Japan
| | - Yohei Nitta
- Center for Transdisciplinary Research, Niigata University, Niigata, Japan.,Brain Research Institute, Niigata University, Niigata, Japan
| | - Yuichi Ishiwata
- Graduate School of Life Science and Technology, Tokyo Institute of Technology, Yokohama, Japan
| | - Riku Iwanaga
- Graduate School of Life Science and Technology, Tokyo Institute of Technology, Yokohama, Japan
| | - Makoto Sato
- Mathematical Neuroscience Unit, Institute for Frontier Science Initiative, Kanazawa University, Kanazawa, Japan.,Laboratory of Developmental Neurobiology, Graduate School of Medical Sciences, Kanazawa University, Kanazawa, Japan
| | - Atsushi Sugie
- Center for Transdisciplinary Research, Niigata University, Niigata, Japan.,Brain Research Institute, Niigata University, Niigata, Japan
| | - Takashi Suzuki
- Graduate School of Life Science and Technology, Tokyo Institute of Technology, Yokohama, Japan
| |
Collapse
|
14
|
Grimbert S, Mastronardi K, Richard V, Christensen R, Law C, Zardoui K, Fay D, Piekny A. Multi-tissue patterning drives anterior morphogenesis of the C. elegans embryo. Dev Biol 2021; 471:49-64. [PMID: 33309948 PMCID: PMC8597047 DOI: 10.1016/j.ydbio.2020.12.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2020] [Revised: 12/01/2020] [Accepted: 12/02/2020] [Indexed: 11/23/2022]
Abstract
Complex structures derived from multiple tissue types are challenging to study in vivo, and our knowledge of how cells from different tissues are coordinated is limited. Model organisms have proven invaluable for improving our understanding of how chemical and mechanical cues between cells from two different tissues can govern specific morphogenetic events. Here we used Caenorhabditis elegans as a model system to show how cells from three different tissues are coordinated to give rise to the anterior lumen. While some aspects of pharyngeal morphogenesis have been well-described, it is less clear how cells from the pharynx, epidermis and neuroblasts coordinate to define the location of the anterior lumen and supporting structures. Using various microscopy and software approaches, we define the movements and patterns of these cells during anterior morphogenesis. Projections from the anterior-most pharyngeal cells (arcade cells) provide the first visible markers for the location of the future lumen, and facilitate patterning of the surrounding neuroblasts. These neuroblast patterns control the rate of migration of the anterior epidermal cells, whereas the epidermal cells ultimately reinforce and control the position of the future lumen, as they must join with the pharyngeal cells for their epithelialization. Our studies are the first to characterize anterior morphogenesis in C. elegans in detail and should lay the framework for identifying how these different patterns are controlled at the molecular level.
Collapse
Affiliation(s)
- Stéphanie Grimbert
- Department of Biology, Concordia University, 7141 Sherbrooke Street West, Montreal, Quebec, H4B 1R6, Canada
| | - Karina Mastronardi
- Department of Biology, Concordia University, 7141 Sherbrooke Street West, Montreal, Quebec, H4B 1R6, Canada
| | - Victoria Richard
- Department of Biology, Concordia University, 7141 Sherbrooke Street West, Montreal, Quebec, H4B 1R6, Canada
| | - Ryan Christensen
- Laboratory of High Resolution Optical Imaging, NIH/NIBIB, 13 South Drive, Bethesda, MD, 20892, USA
| | - Christopher Law
- Department of Biology, Concordia University, 7141 Sherbrooke Street West, Montreal, Quebec, H4B 1R6, Canada
| | - Khashayar Zardoui
- Department of Biology, Concordia University, 7141 Sherbrooke Street West, Montreal, Quebec, H4B 1R6, Canada
| | - David Fay
- Department of Molecular Biology, University of Wyoming, 1000 E. University Ave., Laramie, WY, 82071, USA
| | - Alisa Piekny
- Department of Biology, Concordia University, 7141 Sherbrooke Street West, Montreal, Quebec, H4B 1R6, Canada.
| |
Collapse
|
15
|
Moyle MW, Barnes KM, Kuchroo M, Gonopolskiy A, Duncan LH, Sengupta T, Shao L, Guo M, Santella A, Christensen R, Kumar A, Wu Y, Moon KR, Wolf G, Krishnaswamy S, Bao Z, Shroff H, Mohler WA, Colón-Ramos DA. Structural and developmental principles of neuropil assembly in C. elegans. Nature 2021; 591:99-104. [PMID: 33627875 DOI: 10.1038/s41586-020-03169-5] [Citation(s) in RCA: 40] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2020] [Accepted: 11/12/2020] [Indexed: 01/31/2023]
Abstract
Neuropil is a fundamental form of tissue organization within the brain1, in which densely packed neurons synaptically interconnect into precise circuit architecture2,3. However, the structural and developmental principles that govern this nanoscale precision remain largely unknown4,5. Here we use an iterative data coarse-graining algorithm termed 'diffusion condensation'6 to identify nested circuit structures within the Caenorhabditis elegans neuropil, which is known as the nerve ring. We show that the nerve ring neuropil is largely organized into four strata that are composed of related behavioural circuits. The stratified architecture of the neuropil is a geometrical representation of the functional segregation of sensory information and motor outputs, with specific sensory organs and muscle quadrants mapping onto particular neuropil strata. We identify groups of neurons with unique morphologies that integrate information across strata and that create neural structures that cage the strata within the nerve ring. We use high resolution light-sheet microscopy7,8 coupled with lineage-tracing and cell-tracking algorithms9,10 to resolve the developmental sequence and reveal principles of cell position, migration and outgrowth that guide stratified neuropil organization. Our results uncover conserved structural design principles that underlie the architecture and function of the nerve ring neuropil, and reveal a temporal progression of outgrowth-based on pioneer neurons-that guides the hierarchical development of the layered neuropil. Our findings provide a systematic blueprint for using structural and developmental approaches to understand neuropil organization within the brain.
Collapse
|
16
|
Brittin CA, Cook SJ, Hall DH, Emmons SW, Cohen N. A multi-scale brain map derived from whole-brain volumetric reconstructions. Nature 2021; 591:105-110. [DOI: 10.1038/s41586-021-03284-x] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2020] [Accepted: 01/25/2021] [Indexed: 12/16/2022]
|
17
|
Abstract
Glia make up roughly half of all cells in the mammalian nervous system and play a major part in nervous system development, function, and disease. Although research in the past few decades has shed light on their morphological and functional diversity, there is still much to be known about key aspects of their development such as the generation of glial diversity and the factors governing proper morphogenesis. Glia of the nematode C. elegans possess many developmental and morphological similarities with their vertebrate counterparts and can potentially be used as a model to understand certain aspects of glial biology owing to advantages such as its genetic tractability and fully mapped cell lineage. In this review, we summarize recent progress in our understanding of genetic pathways that regulate glial development in C. elegans and discuss how some of these findings may be conserved.
Collapse
Affiliation(s)
- Albert Zhang
- Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, NC, USA
| | - Dong Yan
- Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, NC, USA.,Department of Neurobiology, Regeneration Next, and Duke Institute for Brain Sciences, Duke University Medical Center, Durham, NC, USA
| |
Collapse
|
18
|
Bowles SN, Johnson CM. Inferences of glia-mediated control in Caenorhabditis elegans. J Neurosci Res 2021; 99:1191-1206. [PMID: 33559247 DOI: 10.1002/jnr.24803] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2021] [Accepted: 01/12/2021] [Indexed: 12/22/2022]
Abstract
Astrocytes modulate synaptic transmission; yet, it remains unclear how glia influence complex behaviors. Here, we explore the effects of Caenorhabditis elegans astrocyte-like cephalic glia (CEPglia ) and the glia-specific bHLH transcription factor HLH-17 on mating behavior and the defecation motor program (DMP). In C. elegans, male mating has been explicitly described through the male tail circuit and is characterized by coordination of multiple independent behaviors to ensure that copulation is achieved. Furthermore, the sex-specific male mating circuitry shares similar components with the DMP, which is complex and rhythmic, and requires a fixed sequence of behaviors to be activated periodically. We found that loss of CEPglia reduced persistence in executing mating behaviors and hindered copulation, while males that lacked HLH-17 demonstrated repetitive prodding behavior that increased the time spent in mating but did not hinder copulation. During the DMP, we found that posterior body wall contractions (pBocs) and enteric muscle contractions (EMCs) were differentially affected by loss of HLH-17 or CEPglia in males and hermaphrodites. pBocs and EMCs required HLH-17 activity in both sexes, whereas loss of CEPglia alone did not affect DMP in males. Our data suggest that CEPglia mediate complex behaviors by signaling to the GABAergic DVB neuron, and that HLH-17 activity influences those discrete steps within those behaviors. Collectively, these data provide evidence of glia as a link in cooperative regulation of complex and rhythmic behavior that, in C. elegans links circuitry in the head and the tail.
Collapse
Affiliation(s)
| | - Casonya M Johnson
- Department of Biology, Georgia State University, Atlanta, GA, USA.,Department of Biology, James Madison University, Harrisonburg, VA, USA
| |
Collapse
|
19
|
Nagai J, Yu X, Papouin T, Cheong E, Freeman MR, Monk KR, Hastings MH, Haydon PG, Rowitch D, Shaham S, Khakh BS. Behaviorally consequential astrocytic regulation of neural circuits. Neuron 2020; 109:576-596. [PMID: 33385325 DOI: 10.1016/j.neuron.2020.12.008] [Citation(s) in RCA: 115] [Impact Index Per Article: 28.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2020] [Revised: 11/23/2020] [Accepted: 12/07/2020] [Indexed: 12/16/2022]
Abstract
Astrocytes are a large and diverse population of morphologically complex cells that exist throughout nervous systems of multiple species. Progress over the last two decades has shown that astrocytes mediate developmental, physiological, and pathological processes. However, a long-standing open question is how astrocytes regulate neural circuits in ways that are behaviorally consequential. In this regard, we summarize recent studies using Caenorhabditis elegans, Drosophila melanogaster, Danio rerio, and Mus musculus. The data reveal diverse astrocyte mechanisms operating in seconds or much longer timescales within neural circuits and shaping multiple behavioral outputs. We also refer to human diseases that have a known primary astrocytic basis. We suggest that including astrocytes in mechanistic, theoretical, and computational studies of neural circuits provides new perspectives to understand behavior, its regulation, and its disease-related manifestations.
Collapse
Affiliation(s)
- Jun Nagai
- Department of Physiology, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA 90095-1751, USA; RIKEN Center for Brain Science, 2-1 Hirosawa Wako City, Saitama 351-0198, Japan
| | - Xinzhu Yu
- Department of Physiology, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA 90095-1751, USA; Department of Molecular and Integrative Physiology, University of Illinois at Urbana-Champaign, 514 Burrill Hall, 407 S. Goodwin Ave, Urbana, IL 61801, USA
| | - Thomas Papouin
- Department of Neuroscience, Washington University in St. Louis, School of Medicine, Campus Box 8108, 660 South Euclid Ave., St. Louis, MO 63110, USA
| | - Eunji Cheong
- Department of Biotechnology, College of Life Science and Biotechnology, Yonsei University, Seoul 03722, South Korea
| | - Marc R Freeman
- The Vollum Institute, Oregon Health & Science University, 3181 SW Sam Jackson Park Road, Portland, OR 97239, USA
| | - Kelly R Monk
- The Vollum Institute, Oregon Health & Science University, 3181 SW Sam Jackson Park Road, Portland, OR 97239, USA
| | - Michael H Hastings
- MRC Laboratory of Molecular Biology, Cambridge Biomedical Campus, Francis Crick Avenue, Cambridge CB2 0QH, UK
| | - Philip G Haydon
- Department of Neuroscience, Tufts University School of Medicine, 136 Harrison Avenue, Boston, MA 02111, USA
| | - David Rowitch
- Department of Paediatrics, Wellcome-MRC Cambridge Stem Cell Institute, University of Cambridge, Cambridge, UK; Departments of Pediatrics and Neurosurgery, Eli and Edythe Broad Center of Regeneration Medicine and Stem Cell Research, University of California, San Francisco, San Francisco, CA, USA
| | - Shai Shaham
- Laboratory of Developmental Genetics, The Rockefeller University, 1230 York Avenue, New York, NY 10065, USA
| | - Baljit S Khakh
- Department of Physiology, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA 90095-1751, USA; Department of Neurobiology, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA 90095-1751, USA.
| |
Collapse
|
20
|
Lago-Baldaia I, Fernandes VM, Ackerman SD. More Than Mortar: Glia as Architects of Nervous System Development and Disease. Front Cell Dev Biol 2020; 8:611269. [PMID: 33381506 PMCID: PMC7767919 DOI: 10.3389/fcell.2020.611269] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2020] [Accepted: 11/17/2020] [Indexed: 12/12/2022] Open
Abstract
Glial cells are an essential component of the nervous system of vertebrates and invertebrates. In the human brain, glia are as numerous as neurons, yet the importance of glia to nearly every aspect of nervous system development has only been expounded over the last several decades. Glia are now known to regulate neural specification, synaptogenesis, synapse function, and even broad circuit function. Given their ubiquity, it is not surprising that the contribution of glia to neuronal disease pathogenesis is a growing area of research. In this review, we will summarize the accumulated evidence of glial participation in several distinct phases of nervous system development and organization-neural specification, circuit wiring, and circuit function. Finally, we will highlight how these early developmental roles of glia contribute to nervous system dysfunction in neurodevelopmental and neurodegenerative disorders.
Collapse
Affiliation(s)
- Inês Lago-Baldaia
- Department of Cell and Developmental Biology, University College London, London, United Kingdom
| | - Vilaiwan M. Fernandes
- Department of Cell and Developmental Biology, University College London, London, United Kingdom
| | - Sarah D. Ackerman
- Institute of Neuroscience, Howard Hughes Medical Institute, University of Oregon, Eugene, OR, United States
| |
Collapse
|
21
|
Abstract
The hypothalamic-pituitary-gonadal axis is controlled by gonadotropin-releasing hormone (GnRH) released by the hypothalamus. Disruption of this system leads to impaired reproductive maturation and function, a condition known as hypogonadotropic hypogonadism (HH). Most studies to date have focused on genetic causes of HH that impact neuronal development and function. However, variants may also impact the functioning of non-neuronal cells known as glia. Glial cells make up 50% of brain cells of humans, primates, and rodents. They include radial glial cells, microglia, astrocytes, tanycytes, oligodendrocytes, and oligodendrocyte precursor cells. Many of these cells influence the hypothalamic neuroendocrine system controlling fertility. Indeed, glia regulate GnRH neuronal activity and secretion, acting both at their cell bodies and their nerve endings. Recent work has also made clear that these interactions are an essential aspect of how the HPG axis integrates endocrine, metabolic, and environmental signals to control fertility. Recognition of the clinical importance of interactions between glia and the GnRH network may pave the way for the development of new treatment strategies for dysfunctions of puberty and adult fertility.
Collapse
Affiliation(s)
- Kathryn B Smedlund
- Department of Physiology and Pharmacology, College of Medicine and Life Sciences, The University of Toledo, Toledo, OH, 43614, USA; Center for Diabetes and Endocrine Research, College of Medicine and Life Sciences, The University of Toledo, Toledo, OH, 43614, USA
| | - Jennifer W Hill
- Department of Physiology and Pharmacology, College of Medicine and Life Sciences, The University of Toledo, Toledo, OH, 43614, USA; Center for Diabetes and Endocrine Research, College of Medicine and Life Sciences, The University of Toledo, Toledo, OH, 43614, USA.
| |
Collapse
|
22
|
Druckenbrod NR, Hale EB, Olukoya OO, Shatzer WE, Goodrich LV. Neuronal processes and glial precursors form a scaffold for wiring the developing mouse cochlea. Nat Commun 2020; 11:5866. [PMID: 33203842 DOI: 10.1038/s41467-020-19521-2] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2019] [Accepted: 10/02/2020] [Indexed: 01/20/2023] Open
Abstract
In the developing nervous system, axons navigate through complex terrains that change depending on when and where outgrowth begins. For instance, in the developing cochlea, spiral ganglion neurons extend their peripheral processes through a growing and heterogeneous environment en route to their final targets, the hair cells. Although the basic principles of axon guidance are well established, it remains unclear how axons adjust strategies over time and space. Here, we show that neurons with different positions in the spiral ganglion employ different guidance mechanisms, with evidence for both glia-guided growth and fasciculation along a neuronal scaffold. Processes from neurons in the rear of the ganglion are more directed and grow faster than those from neurons at the border of the ganglion. Further, processes at the wavefront grow more efficiently when in contact with glial precursors growing ahead of them. These findings suggest a tiered mechanism for reliable axon guidance.
Collapse
|
23
|
Sherry T, Handley A, Nicholas HR, Pocock R. Harmonization of L1CAM expression facilitates axon outgrowth and guidance of a motor neuron. Development 2020; 147:dev.193805. [PMID: 32994172 DOI: 10.1242/dev.193805] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2020] [Accepted: 09/18/2020] [Indexed: 12/28/2022]
Abstract
Brain development requires precise regulation of axon outgrowth, guidance and termination by multiple signaling and adhesion molecules. How the expression of these neurodevelopmental regulators is transcriptionally controlled is poorly understood. The Caenorhabditis elegans SMD motor neurons terminate axon outgrowth upon sexual maturity and partially retract their axons during early adulthood. Here we show that C-terminal binding protein 1 (CTBP-1), a transcriptional corepressor, is required for correct SMD axonal development. Loss of CTBP-1 causes multiple defects in SMD axon development: premature outgrowth, defective guidance, delayed termination and absence of retraction. CTBP-1 controls SMD axon guidance by repressing the expression of SAX-7, an L1 cell adhesion molecule (L1CAM). CTBP-1-regulated repression is crucial because deregulated SAX-7/L1CAM causes severely aberrant SMD axons. We found that axonal defects caused by deregulated SAX-7/L1CAM are dependent on a distinct L1CAM, called LAD-2, which itself plays a parallel role in SMD axon guidance. Our results reveal that harmonization of L1CAM expression controls the development and maturation of a single neuron.
Collapse
Affiliation(s)
- Tessa Sherry
- Development and Stem Cells Program, Monash Biomedicine Discovery Institute and Department of Anatomy and Developmental Biology, Monash University, Melbourne, Victoria 3800, Australia.,School of Life and Environmental Sciences, The University of Sydney, Sydney, NSW 2006, Australia
| | - Ava Handley
- Development and Stem Cells Program, Monash Biomedicine Discovery Institute and Department of Anatomy and Developmental Biology, Monash University, Melbourne, Victoria 3800, Australia
| | - Hannah R Nicholas
- School of Life and Environmental Sciences, The University of Sydney, Sydney, NSW 2006, Australia
| | - Roger Pocock
- Development and Stem Cells Program, Monash Biomedicine Discovery Institute and Department of Anatomy and Developmental Biology, Monash University, Melbourne, Victoria 3800, Australia
| |
Collapse
|
24
|
Duan D, Zhang H, Yue X, Fan Y, Xue Y, Shao J, Ding G, Chen D, Li S, Cheng H, Zhang X, Zou W, Liu J, Zhao J, Wang L, Zhao B, Wang Z, Xu S, Wen Q, Liu J, Duan S, Kang L. Sensory Glia Detect Repulsive Odorants and Drive Olfactory Adaptation. Neuron 2020; 108:707-721.e8. [PMID: 32970991 DOI: 10.1016/j.neuron.2020.08.026] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2020] [Revised: 07/25/2020] [Accepted: 08/26/2020] [Indexed: 12/18/2022]
Abstract
Glia are typically considered as supporting cells for neural development and synaptic transmission. Here, we report an active role of a glia in olfactory transduction. As a polymodal sensory neuron in C. elegans, the ASH neuron is previously known to detect multiple aversive odorants. We reveal that the AMsh glia, a sheath for multiple sensory neurons including ASH, cell-autonomously respond to aversive odorants via G-protein-coupled receptors (GPCRs) distinct from those in ASH. Upon activation, the AMsh glia suppress aversive odorant-triggered avoidance and promote olfactory adaptation by inhibiting the ASH neuron via GABA signaling. Thus, we propose a novel two-receptor model where the glia and sensory neuron jointly mediate adaptive olfaction. Our study reveals a non-canonical function of glial cells in olfactory transduction, which may provide new insights into the glia-like supporting cells in mammalian sensory procession.
Collapse
Affiliation(s)
- Duo Duan
- Department of Neurobiology and Department of Neurosurgery of the First Affiliated Hospital, Zhejiang University School of Medicine, Zhejiang 310053, China; NHC and CAMS Key Laboratory of Medical Neurobiology, MOE Frontier Science Center for Brain Research and Brain-Machine Integration, School of Brain Science and Brain Medicine, Zhejiang University, Hangzhou, Zhejiang 310053, China; Department of Neurology of Second Affiliated Hospital, Zhejiang University School of Medicine, Zhejiang 310053, China
| | - Hu Zhang
- Department of Neurobiology and Department of Neurosurgery of the First Affiliated Hospital, Zhejiang University School of Medicine, Zhejiang 310053, China; NHC and CAMS Key Laboratory of Medical Neurobiology, MOE Frontier Science Center for Brain Research and Brain-Machine Integration, School of Brain Science and Brain Medicine, Zhejiang University, Hangzhou, Zhejiang 310053, China
| | - Xiaomin Yue
- Department of Neurobiology and Department of Neurosurgery of the First Affiliated Hospital, Zhejiang University School of Medicine, Zhejiang 310053, China; NHC and CAMS Key Laboratory of Medical Neurobiology, MOE Frontier Science Center for Brain Research and Brain-Machine Integration, School of Brain Science and Brain Medicine, Zhejiang University, Hangzhou, Zhejiang 310053, China
| | - Yuedan Fan
- Department of Neurobiology and Department of Neurosurgery of the First Affiliated Hospital, Zhejiang University School of Medicine, Zhejiang 310053, China; NHC and CAMS Key Laboratory of Medical Neurobiology, MOE Frontier Science Center for Brain Research and Brain-Machine Integration, School of Brain Science and Brain Medicine, Zhejiang University, Hangzhou, Zhejiang 310053, China
| | - Yadan Xue
- Department of Neurobiology and Department of Neurosurgery of the First Affiliated Hospital, Zhejiang University School of Medicine, Zhejiang 310053, China
| | - Jiajie Shao
- Department of Neurobiology and Department of Neurosurgery of the First Affiliated Hospital, Zhejiang University School of Medicine, Zhejiang 310053, China
| | - Gang Ding
- Department of Neurobiology and Department of Neurosurgery of the First Affiliated Hospital, Zhejiang University School of Medicine, Zhejiang 310053, China
| | - Du Chen
- Department of Neurobiology and Department of Neurosurgery of the First Affiliated Hospital, Zhejiang University School of Medicine, Zhejiang 310053, China
| | - Shitian Li
- Department of Neurobiology and Department of Neurosurgery of the First Affiliated Hospital, Zhejiang University School of Medicine, Zhejiang 310053, China
| | - Hankui Cheng
- Department of Neurobiology and Department of Neurosurgery of the First Affiliated Hospital, Zhejiang University School of Medicine, Zhejiang 310053, China
| | - Xiaoyan Zhang
- Department of Neurobiology and Department of Neurosurgery of the First Affiliated Hospital, Zhejiang University School of Medicine, Zhejiang 310053, China
| | - Wenjuan Zou
- Department of Neurobiology and Department of Neurosurgery of the First Affiliated Hospital, Zhejiang University School of Medicine, Zhejiang 310053, China
| | - Jia Liu
- Department of Neurobiology and Department of Neurosurgery of the First Affiliated Hospital, Zhejiang University School of Medicine, Zhejiang 310053, China
| | - Jian Zhao
- Department of Neurobiology and Department of Neurosurgery of the First Affiliated Hospital, Zhejiang University School of Medicine, Zhejiang 310053, China
| | - Linmei Wang
- Department of Neurobiology and Department of Neurosurgery of the First Affiliated Hospital, Zhejiang University School of Medicine, Zhejiang 310053, China
| | - Bingzhen Zhao
- Chinese Academy of Sciences Key Laboratory of Brain Function and Disease, School of Life Sciences, University of Science and Technology of China, Hefei, Anhui 230026, China
| | - Zhiping Wang
- Department of Neurobiology and Department of Neurosurgery of the First Affiliated Hospital, Zhejiang University School of Medicine, Zhejiang 310053, China
| | - Suhong Xu
- Center for Stem Cell and Regenerative Medicine, Zhejiang University School of Medicine, Hangzhou, Zhejiang 310058, China
| | - Quan Wen
- Chinese Academy of Sciences Key Laboratory of Brain Function and Disease, School of Life Sciences, University of Science and Technology of China, Hefei, Anhui 230026, China
| | - Jie Liu
- Monash Biomedicine Discovery Institute, Department of Anatomy and Developmental Biology, Monash University, Clayton, VIC 3800, Australia
| | - Shumin Duan
- NHC and CAMS Key Laboratory of Medical Neurobiology, MOE Frontier Science Center for Brain Research and Brain-Machine Integration, School of Brain Science and Brain Medicine, Zhejiang University, Hangzhou, Zhejiang 310053, China; Department of Neurology of Second Affiliated Hospital, Zhejiang University School of Medicine, Zhejiang 310053, China.
| | - Lijun Kang
- Department of Neurobiology and Department of Neurosurgery of the First Affiliated Hospital, Zhejiang University School of Medicine, Zhejiang 310053, China; NHC and CAMS Key Laboratory of Medical Neurobiology, MOE Frontier Science Center for Brain Research and Brain-Machine Integration, School of Brain Science and Brain Medicine, Zhejiang University, Hangzhou, Zhejiang 310053, China.
| |
Collapse
|
25
|
Abstract
Glia shape the development and function of the C. elegans nervous system, especially its sense organs and central neuropil (nerve ring). Cell-type-specific promoters allow investigators to label or manipulate individual glial cell types, and therefore provide a key tool for deciphering glial function. In this technical resource, we compare the specificity, brightness, and consistency of cell-type-specific promoters for C. elegans glia. We identify a set of promoters for the study of seven glial cell types (F16F9.3, amphid and phasmid sheath glia; F11C7.2, amphid sheath glia only; grl-2, amphid and phasmid socket glia; hlh-17, cephalic (CEP) sheath glia; and grl-18, inner labial (IL) socket glia) as well as a pan-glial promoter (mir-228). We compare these promoters to promoters that are expressed more variably in combinations of glial cell types (delm-1 and itx-1). We note that the expression of some promoters depends on external conditions or the internal state of the organism, such as developmental stage, suggesting glial plasticity. Finally, we demonstrate an approach for prospectively identifying cell-type-specific glial promoters using existing single-cell sequencing data, and we use this approach to identify two novel promoters specific to IL socket glia (col-53 and col-177).
Collapse
Affiliation(s)
- Wendy Fung
- These authors contributed equally to this work
- Department of Genetics, Blavatnik Institute, Harvard Medical School and Boston Children’s Hospital, Boston MA 02115
| | - Leigh Wexler
- These authors contributed equally to this work
- Department of Genetics, Blavatnik Institute, Harvard Medical School and Boston Children’s Hospital, Boston MA 02115
| | - Maxwell G. Heiman
- Department of Genetics, Blavatnik Institute, Harvard Medical School and Boston Children’s Hospital, Boston MA 02115
| |
Collapse
|
26
|
Christensen EL, Beasley A, Radchuk J, Mielko ZE, Preston E, Stuckett S, Murray JI, Hudson ML. ngn-1/neurogenin Activates Transcription of Multiple Terminal Selector Transcription Factors in the Caenorhabditis elegans Nervous System. G3 (Bethesda) 2020; 10:1949-1962. [PMID: 32273286 PMCID: PMC7263688 DOI: 10.1534/g3.120.401126] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/06/2020] [Accepted: 03/30/2020] [Indexed: 11/18/2022]
Abstract
Proper nervous system development is required for an organism's survival and function. Defects in neurogenesis have been linked to neurodevelopmental disorders such as schizophrenia and autism. Understanding the gene regulatory networks that orchestrate neural development, specifically cascades of proneural transcription factors, can better elucidate which genes are most important during early neurogenesis. Neurogenins are a family of deeply conserved factors shown to be both necessary and sufficient for the development of neural subtypes. However, the immediate downstream targets of neurogenin are not well characterized. The objective of this study was to further elucidate the role of ngn-1/neurogenin in nervous system development and to identify its downstream transcriptional targets, using the nematode Caenorhabditis elegans as a model for this work. We found that ngn-1 is required for axon outgrowth, nerve ring architecture, and neuronal cell fate specification. We also showed that ngn-1 may have roles in neuroblast migration and epithelial integrity during embryonic development. Using RNA sequencing and comparative transcriptome analysis, we identified eight transcription factors (hlh-34/NPAS1, unc-42/PROP1, ceh-17/PHOX2A, lim-4/LHX6, fax-1/NR2E3, lin-11/LHX1, tlp-1/ZNF503, and nhr-23/RORB) whose transcription is activated, either directly or indirectly, by ngn-1 Our results show that ngn-1 has a role in transcribing known terminal regulators that establish and maintain cell fate of differentiated neural subtypes and confirms that ngn-1 functions as a proneural transcription factor in C. elegans neurogenesis.
Collapse
Affiliation(s)
- Elyse L Christensen
- Department of Molecular and Cellular Biology, Kennesaw State University, GA 30144
| | - Alexandra Beasley
- Department of Molecular and Cellular Biology, Kennesaw State University, GA 30144
| | - Jessica Radchuk
- Department of Molecular and Cellular Biology, Kennesaw State University, GA 30144
| | - Zachery E Mielko
- Department of Molecular and Cellular Biology, Kennesaw State University, GA 30144
| | - Elicia Preston
- Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104
| | - Sidney Stuckett
- Department of Molecular and Cellular Biology, Kennesaw State University, GA 30144
| | - John I Murray
- Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104
| | - Martin L Hudson
- Department of Molecular and Cellular Biology, Kennesaw State University, GA 30144
| |
Collapse
|
27
|
Frakes AE, Metcalf MG, Tronnes SU, Bar-Ziv R, Durieux J, Gildea HK, Kandahari N, Monshietehadi S, Dillin A. Four glial cells regulate ER stress resistance and longevity via neuropeptide signaling in C. elegans. Science 2020; 367:436-440. [PMID: 31974253 DOI: 10.1126/science.aaz6896] [Citation(s) in RCA: 54] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2019] [Accepted: 11/29/2019] [Indexed: 12/21/2022]
Abstract
The ability of the nervous system to sense cellular stress and coordinate protein homeostasis is essential for organismal health. Unfortunately, stress responses that mitigate disturbances in proteostasis, such as the unfolded protein response of the endoplasmic reticulum (UPRER), become defunct with age. In this work, we expressed the constitutively active UPRER transcription factor, XBP-1s, in a subset of astrocyte-like glia, which extended the life span in Caenorhabditis elegans Glial XBP-1s initiated a robust cell nonautonomous activation of the UPRER in distal cells and rendered animals more resistant to protein aggregation and chronic ER stress. Mutants deficient in neuropeptide processing and secretion suppressed glial cell nonautonomous induction of the UPRER and life-span extension. Thus, astrocyte-like glial cells play a role in regulating organismal ER stress resistance and longevity.
Collapse
Affiliation(s)
- Ashley E Frakes
- Department of Molecular and Cell Biology, University of California, Berkeley, CA 94720, USA.,Howard Hughes Medical Institute, University of California, Berkeley, CA 94720, USA
| | - Melissa G Metcalf
- Department of Molecular and Cell Biology, University of California, Berkeley, CA 94720, USA.,Howard Hughes Medical Institute, University of California, Berkeley, CA 94720, USA
| | - Sarah U Tronnes
- Department of Molecular and Cell Biology, University of California, Berkeley, CA 94720, USA.,Howard Hughes Medical Institute, University of California, Berkeley, CA 94720, USA
| | - Raz Bar-Ziv
- Department of Molecular and Cell Biology, University of California, Berkeley, CA 94720, USA.,Howard Hughes Medical Institute, University of California, Berkeley, CA 94720, USA
| | - Jenni Durieux
- Department of Molecular and Cell Biology, University of California, Berkeley, CA 94720, USA.,Howard Hughes Medical Institute, University of California, Berkeley, CA 94720, USA
| | - Holly K Gildea
- Department of Molecular and Cell Biology, University of California, Berkeley, CA 94720, USA.,Howard Hughes Medical Institute, University of California, Berkeley, CA 94720, USA
| | - Nazineen Kandahari
- Department of Molecular and Cell Biology, University of California, Berkeley, CA 94720, USA.,Howard Hughes Medical Institute, University of California, Berkeley, CA 94720, USA
| | - Samira Monshietehadi
- Department of Molecular and Cell Biology, University of California, Berkeley, CA 94720, USA.,Howard Hughes Medical Institute, University of California, Berkeley, CA 94720, USA
| | - Andrew Dillin
- Department of Molecular and Cell Biology, University of California, Berkeley, CA 94720, USA. .,Howard Hughes Medical Institute, University of California, Berkeley, CA 94720, USA
| |
Collapse
|
28
|
Abstract
The connectomes of organisms of the same species show remarkable architectural and often local wiring similarity, raising the question: where and how is neuronal connectivity encoded? Here, we start from the hypothesis that the genetic identity of neurons guides synapse and gap-junction formation and show that such genetically driven wiring predicts the existence of specific biclique motifs in the connectome. We identify a family of large, statistically significant biclique subgraphs in the connectomes of three species and show that within many of the observed bicliques the neurons share statistically significant expression patterns and morphological characteristics, supporting our expectation of common genetic factors that drive the synapse formation within these subgraphs. The proposed connectome model offers a self-consistent framework to link the genetics of an organism to the reproducible architecture of its connectome, offering experimentally falsifiable predictions on the genetic factors that drive the formation of individual neuronal circuits.
Collapse
Affiliation(s)
| | - Albert-László Barabási
- Network Science Institute, Northeastern University, Boston, MA 02115, USA; Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA; Department of Data and Network Science, Central European University, Budapest 1051, Hungary.
| |
Collapse
|
29
|
Ke T, Sidoryk-Wegrzynowicz M, Pajarillo E, Rizor A, Soares FAA, Lee E, Aschner M. Role of Astrocytes in Manganese Neurotoxicity Revisited. Neurochem Res 2019; 44:2449-2459. [PMID: 31571097 PMCID: PMC7757856 DOI: 10.1007/s11064-019-02881-7] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2019] [Revised: 09/13/2019] [Accepted: 09/16/2019] [Indexed: 12/17/2022]
Abstract
Manganese (Mn) overexposure is a public health concern due to its widespread industrial usage and the risk for environmental contamination. The clinical symptoms of Mn neurotoxicity, or manganism, share several pathological features of Parkinson's disease (PD). Biologically, Mn is an essential trace element, and Mn in the brain is preferentially localized in astrocytes. This review summarizes the role of astrocytes in Mn-induced neurotoxicity, specifically on the role of neurotransmitter recycling, neuroinflammation, and genetics. Mn overexposure can dysregulate astrocytic cycling of glutamine (Gln) and glutamate (Glu), which is the basis for Mn-induced excitotoxic neuronal injury. In addition, reactive astrocytes are important mediators of Mn-induced neuronal damage by potentiating neuroinflammation. Genetic studies, including those with Caenorhabditis elegans (C. elegans) have uncovered several genes associated with Mn neurotoxicity. Though we have yet to fully understand the role of astrocytes in the pathologic changes characteristic of manganism, significant strides have been made over the last two decades in deciphering the role of astrocytes in Mn-induced neurotoxicity and neurodegeneration.
Collapse
Affiliation(s)
- Tao Ke
- Department of Molecular Pharmacology, Albert Einstein College of Medicine, Bronx, NY, 10461, USA
| | - Marta Sidoryk-Wegrzynowicz
- Laboratory of Pathoneurochemistry, Department of Neurochemistry, Mossakowski Medical Research Centre, Polish Academy of Sciences, 5 Pawinskiego Street, 02-106, Warsaw, Poland
| | - Edward Pajarillo
- Department of Pharmaceutical Sciences, Florida A&M University, Tallahassee, FL, 32307, USA
| | - Asha Rizor
- Department of Pharmaceutical Sciences, Florida A&M University, Tallahassee, FL, 32307, USA
| | - Félix Alexandre Antunes Soares
- Department of Molecular Pharmacology, Albert Einstein College of Medicine, Bronx, NY, 10461, USA.,Department of Biochemistry and Molecular Biology, Federal University of Santa Maria, Santa Maria, RS, Brazil
| | - Eunsook Lee
- Department of Pharmaceutical Sciences, Florida A&M University, Tallahassee, FL, 32307, USA
| | - Michael Aschner
- Department of Molecular Pharmacology, Albert Einstein College of Medicine, Bronx, NY, 10461, USA. .,Department of Molecular Pharmacology, Albert Einstein College of Medicine, 1300 Morris Park Avenue, Forchheimer Building, Room 209, Bronx, NY, 10461, USA.
| |
Collapse
|
30
|
Liu Q, Hou A, Zhang Y, Guo Y, Li J, Yao Y, Niu K, Li H, Ma Y, Cao J. MiR-190a potentially ameliorates postoperative cognitive dysfunction by regulating Tiam1. BMC Genomics 2019; 20:670. [PMID: 31438846 DOI: 10.1186/s12864-019-6035-0] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2019] [Accepted: 08/15/2019] [Indexed: 02/08/2023] Open
Abstract
BACKGROUND Postoperative cognitive dysfunction (POCD) affects a large number of post-surgery patients, especially for the elderly. However, the etiology of this neurocognitive disorder is largely unknown. Even if several studies have reported a small number of miRNAs as the essential modulatory factors in POCD, these findings are still rather limited. The aim of current study was to screen the POCD-related miRNAs in the hippocampus tissues and investigate the target genes of differentially expressed miRNAs and their biological functions underlying POCD pathophysiology. METHODS The miRNA microarray was used to find the abnormal expression of miRNAs in the hippocampus tissues from the POCD model mice to normal mice (Discovery cohort, 3 vs 3). The nominal significant results were validated in an independent sample of hippocampus tissues of 10 mice based on same miRNA microarray (Replication cohort, 5 vs 5). Expression level of the most significantly abnormal miRNA was further validated by real-time quantitative polymerase chain reaction (PCR). To determine the expression pattern among miRNAs and genes and detect the interactions, we conducted a weighted gene co-expression network analysis (WGCNA) in the miRNAs and genes expression data from hippocampus tissue of wild type mice (n = 24). The target genes of miRNAs were predicted using the miRWalk3.0 software. Furthermore, we used the ClueGO software to decipher the pathways network and reveal the biological functions of target genes of miRNAs. RESULTS We found that nine miRNAs showed significant associations with POCD in both datasets. Among these miRNAs, mmu-miR-190a-3p was the most significant one. By performing WGCNA analysis, we found 25 co-expression modules, of which mmu-miR-190a-3p was significantly anti-correlated with red module. Moreover, in the red module, 314 genes were significantly enriched in four pathways such as axon guidance and calcium signaling pathway, which are well-documented to be associated with psychiatric disorders and brain development. Also, 169 of the 314 genes were highly correlated with mmu-miR-190a-3p, and four genes (Sphkap, Arhgef25, Tiam1, and Ntrk3) had putative binding sites at 3'-UTR of mmu-miR-190a-3p. Based on protein-protein network analysis, we detected that Tiam1 was a central gene regulated by the mmu-miR-190a-3p. CONCLUSIONS Taken together, we conclude that mmu-miR-190a-3p is involved in the etiology of POCD and may serve as a novel predictive indicator for POCD.
Collapse
|
31
|
Abstract
Glia have been suggested to regulate sleep-like states in vertebrates and invertebrates alike. In the nematode Caenorhabditis elegans, sleep is associated with molting between larval stages. To understand if glia modulate neural circuits driving sleep in C. elegans larvae, we ablated the astrocyte-like CEPsh glia. We found that glia-ablated animals exhibit episodes of immobility preceding sleep, prolonged sleep, molting-independent short-duration locomotory pausing, and delayed development. CEPsh glia ensheath synapses between the sleep-associated ALA neuron and its postsynaptic partner AVE, a major locomotion interneuron. While AVE calcium transients normally correlate with head retraction, glia ablation results in prolonged calcium transients that are uncoupled from movement. Strikingly, all these glia ablation defects are suppressed by the ablation of ALA. Our results suggest that glia attenuate sleep-promoting inhibitory connections between ALA and AVE, uncovering specific roles for glia in sleep behavior. We propose that similar mechanisms may underlie glial roles in sleep in other animals.
Collapse
Affiliation(s)
- Menachem Katz
- Laboratory of Developmental Genetics, The Rockefeller University, 1230 York Avenue, New York, NY 10065, USA
| | - Francis Corson
- Laboratoire de Physique Statistique, Ecole Normale Supérieure, CNRS, Université Pierre et Marie Curie, Université Paris Diderot, 75005 Paris, France
| | - Shachar Iwanir
- University of Chicago, GCIS E139F, 929 E. 57th St., Chicago, IL 60637, USA
| | - David Biron
- University of Chicago, GCIS E139F, 929 E. 57th St., Chicago, IL 60637, USA
| | - Shai Shaham
- Laboratory of Developmental Genetics, The Rockefeller University, 1230 York Avenue, New York, NY 10065, USA.
| |
Collapse
|
32
|
Katz M, Corson F, Keil W, Singhal A, Bae A, Lu Y, Liang Y, Shaham S. Glutamate spillover in C. elegans triggers repetitive behavior through presynaptic activation of MGL-2/mGluR5. Nat Commun 2019; 10:1882. [PMID: 31015396 PMCID: PMC6478929 DOI: 10.1038/s41467-019-09581-4] [Citation(s) in RCA: 37] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2018] [Accepted: 03/20/2019] [Indexed: 01/08/2023] Open
Abstract
Glutamate is a major excitatory neurotransmitter, and impaired glutamate clearance following synaptic release promotes spillover, inducing extra-synaptic signaling. The effects of glutamate spillover on animal behavior and its neural correlates are poorly understood. We developed a glutamate spillover model in Caenorhabditis elegans by inactivating the conserved glial glutamate transporter GLT-1. GLT-1 loss drives aberrant repetitive locomotory reversal behavior through uncontrolled oscillatory release of glutamate onto AVA, a major interneuron governing reversals. Repetitive glutamate release and reversal behavior require the glutamate receptor MGL-2/mGluR5, expressed in RIM and other interneurons presynaptic to AVA. mgl-2 loss blocks oscillations and repetitive behavior; while RIM activation is sufficient to induce repetitive reversals in glt-1 mutants. Repetitive AVA firing and reversals require EGL-30/Gαq, an mGluR5 effector. Our studies reveal that cyclic autocrine presynaptic activation drives repetitive reversals following glutamate spillover. That mammalian GLT1 and mGluR5 are implicated in pathological motor repetition suggests a common mechanism controlling repetitive behaviors. Katz and colleagues examine glutamate spillover effects on C. elegans behaviour. They show that impaired synaptic glutamate clearance in glial glutamate transporter mutants, causes presynaptic mgl-2/mGluR5 activation, generating postsynaptic neural activity oscillations driving repetitive behaviour.
Collapse
Affiliation(s)
- Menachem Katz
- Laboratory of Developmental Genetics, The Rockefeller University, 1230 York Avenue, New York, NY, 10065, USA
| | - Francis Corson
- Laboratoire de Physique Statistique, Ecole Normale Supérieure, CNRS, Université Pierre et Marie Curie, Université Paris Diderot, 75005, Paris, France
| | - Wolfgang Keil
- Laboratory of Developmental Genetics, The Rockefeller University, 1230 York Avenue, New York, NY, 10065, USA.,Center for Studies in Physics and Biology, The Rockefeller University, 1230 York Avenue, New York, NY, 10065, USA
| | - Anupriya Singhal
- Laboratory of Developmental Genetics, The Rockefeller University, 1230 York Avenue, New York, NY, 10065, USA
| | - Andrea Bae
- Laboratory of Developmental Genetics, The Rockefeller University, 1230 York Avenue, New York, NY, 10065, USA
| | - Yun Lu
- Laboratory of Developmental Genetics, The Rockefeller University, 1230 York Avenue, New York, NY, 10065, USA
| | - Yupu Liang
- Research Bioinformatics, The Rockefeller University, 1230 York Avenue, New York, NY, 10065, USA
| | - Shai Shaham
- Laboratory of Developmental Genetics, The Rockefeller University, 1230 York Avenue, New York, NY, 10065, USA.
| |
Collapse
|
33
|
Abstract
How the nervous system is wired has been a central question of neuroscience since the inception of the field, and many of the foundational discoveries and conceptual advances have been made through the study of invertebrate experimental organisms, including Caenorhabditis elegans and Drosophila melanogaster. Although many guidance molecules and receptors have been identified, recent experiments have shed light on the many modes of action for these pathways. Here, we summarize the recent progress in determining how the physical and temporal constraints of the surrounding environment provide instructive regulations in nervous system wiring. We use Netrin and its receptors as an example to analyze the complexity of how they guide neurite outgrowth. In neurite repair, conserved injury detection and response-signaling pathways regulate gene expression and cytoskeletal dynamics. We also describe recent developments in the research on molecular mechanisms of neurite regeneration in worms and flies.
Collapse
Affiliation(s)
- Claire E Richardson
- Department of Biology, Stanford University, Stanford, California 94305, USA;
| | - Kang Shen
- Department of Biology, Stanford University, Stanford, California 94305, USA; .,Howard Hughes Medical Institute, Stanford University, Stanford, California 94305, USA
| |
Collapse
|
34
|
Abstract
Glia are abundant components of animal nervous systems. Recognized 170 years ago, concerted attempts to understand these cells began only recently. From these investigations glia, once considered passive filler material in the brain, have emerged as active players in neuron development and activity. Glia are essential for nervous system function, and their disruption leads to disease. The nematode Caenorhabditis elegans possesses glial types similar to vertebrate glia, based on molecular, morphological, and functional criteria, and has become a powerful model in which to study glia and their neuronal interactions. Facile genetic and transgenic methods in this animal allow the discovery of genes required for glial functions, and effects of glia at single synapses can be monitored by tracking neuron shape, physiology, or animal behavior. Here, we review recent progress in understanding glia-neuron interactions in C. elegans. We highlight similarities with glia in other animals, and suggest conserved emerging principles of glial function.
Collapse
Affiliation(s)
- Aakanksha Singhvi
- Division of Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, Washington 98109, USA;
| | - Shai Shaham
- Laboratory of Developmental Genetics, The Rockefeller University, New York, NY 10065, USA;
| |
Collapse
|
35
|
Abstract
Glia constitute roughly half of the cells of the central nervous system (CNS) but were long-considered to be static bystanders to its formation and function. Here we provide an overview of how the diverse and dynamic functions of glial cells orchestrate essentially all aspects of nervous system formation and function. Radial glia, astrocytes, oligodendrocyte progenitor cells, oligodendrocytes, and microglia each influence nervous system development, from neuronal birth, migration, axon specification, and growth through circuit assembly and synaptogenesis. As neural circuits mature, distinct glia fulfill key roles in synaptic communication, plasticity, homeostasis, and network-level activity through dynamic monitoring and alteration of CNS structure and function. Continued elucidation of glial cell biology, and the dynamic interactions of neurons and glia, will enrich our understanding of nervous system formation, health, and function.
Collapse
Affiliation(s)
- Nicola J Allen
- Molecular Neurobiology Laboratory, Salk Institute for Biological Studies, 10010 North Torrey Pines Road, La Jolla, CA 92037, USA.
| | - David A Lyons
- Centre for Discovery Brain Sciences, University of Edinburgh, 49 Little France Crescent, Edinburgh EH16 4SB, UK.
| |
Collapse
|
36
|
Nichols EL, Green LA, Smith CJ. Ensheathing cells utilize dynamic tiling of neuronal somas in development and injury as early as neuronal differentiation. Neural Dev 2018; 13:19. [PMID: 30121077 PMCID: PMC6098834 DOI: 10.1186/s13064-018-0115-8] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2018] [Accepted: 07/27/2018] [Indexed: 12/18/2022] Open
Abstract
Background Glial cell ensheathment of specific components of neuronal circuits is essential for nervous system function. Although ensheathment of axonal segments of differentiated neurons has been investigated, ensheathment of neuronal cell somas, especially during early development when neurons are extending processes and progenitor populations are expanding, is still largely unknown. Methods To address this, we used time-lapse imaging in zebrafish during the initial formation of the dorsal root ganglia (DRG). Results Our results show that DRG neurons are ensheathed throughout their entire lifespan by a progenitor population. These ensheathing cells dynamically remodel during development to ensure axons can extend away from the neuronal cell soma into the CNS and out to the skin. As a population, ensheathing cells tile each DRG neuron to ensure neurons are tightly encased. In development and in experimental cell ablation paradigms, the oval shape of DRG neurons dynamically changes during partial unensheathment. During longer extended unensheathment neuronal soma shifting is observed. We further show the intimate relationship of these ensheathing cells with the neurons leads to immediate and choreographed responses to distal axonal damage to the neuron. Conclusion We propose that the ensheathing cells dynamically contribute to the shape and position of neurons in the DRG by their remodeling activity during development and are primed to dynamically respond to injury of the neuron. Electronic supplementary material The online version of this article (10.1186/s13064-018-0115-8) contains supplementary material, which is available to authorized users.
Collapse
Affiliation(s)
- Evan L Nichols
- Department of Biological Sciences, University of Notre Dame, 015 Galvin Life Sciences Building, Notre Dame, IN, 46556, USA
| | - Lauren A Green
- Department of Biological Sciences, University of Notre Dame, 015 Galvin Life Sciences Building, Notre Dame, IN, 46556, USA.,Center for Stem Cells and Regenerative Medicine, University of Notre Dame, Notre Dame, IN, USA
| | - Cody J Smith
- Department of Biological Sciences, University of Notre Dame, 015 Galvin Life Sciences Building, Notre Dame, IN, 46556, USA. .,Center for Stem Cells and Regenerative Medicine, University of Notre Dame, Notre Dame, IN, USA.
| |
Collapse
|
37
|
Insley P, Shaham S. Automated C. elegans embryo alignments reveal brain neuropil position invariance despite lax cell body placement. PLoS One 2018; 13:e0194861. [PMID: 29590193 PMCID: PMC5874040 DOI: 10.1371/journal.pone.0194861] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2017] [Accepted: 03/12/2018] [Indexed: 12/30/2022] Open
Abstract
The Caenorhabditis elegans cell lineage is nearly invariant. Whether this stereotyped cell-division pattern promotes reproducibility in cell shapes/positions is not generally known, as manual spatiotemporal cell-shape/position alignments are labor-intensive, and fully-automated methods are not described. Here, we report automated algorithms for spatiotemporal alignments of C. elegans embryos from pre-morphogenesis to motor-activity initiation. We use sparsely-labeled green-fluorescent nuclei and a pan-nuclear red-fluorescent reporter to register consecutive imaging time points and compare embryos. Using our method, we monitor early assembly of the nerve-ring (NR) brain neuropil. While NR pioneer neurons exhibit reproducible growth kinetics and axon positions, cell-body placements are variable. Thus, pioneer-neuron axon locations, but not cell-body positions, are under selection. We also show that anterior NR displacement in cam-1/ROR Wnt-receptor mutants is not an early NR assembly defect. Our results demonstrate the utility of automated spatiotemporal alignments of C. elegans embryos, and uncover key principles guiding nervous-system development in this animal.
Collapse
Affiliation(s)
- Peter Insley
- Laboratory of Developmental Genetics, The Rockefeller University, New York, NY, United States of America
| | - Shai Shaham
- Laboratory of Developmental Genetics, The Rockefeller University, New York, NY, United States of America
| |
Collapse
|