1
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Kim YD, Park HG, Song S, Kim J, Lee BJ, Broadie K, Lee S. Presynaptic structural and functional plasticity are coupled by convergent Rap1 signaling. J Cell Biol 2024; 223:e202309095. [PMID: 38748250 PMCID: PMC11096849 DOI: 10.1083/jcb.202309095] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2023] [Revised: 02/07/2024] [Accepted: 03/27/2024] [Indexed: 05/18/2024] Open
Abstract
Dynamic presynaptic actin remodeling drives structural and functional plasticity at synapses, but the underlying mechanisms remain largely unknown. Previous work has shown that actin regulation via Rac1 guanine exchange factor (GEF) Vav signaling restrains synaptic growth via bone morphogenetic protein (BMP)-induced receptor macropinocytosis and mediates synaptic potentiation via mobilization of reserve pool vesicles in presynaptic boutons. Here, we find that Gef26/PDZ-GEF and small GTPase Rap1 signaling couples the BMP-induced activation of Abelson kinase to this Vav-mediated macropinocytosis. Moreover, we find that adenylate cyclase Rutabaga (Rut) signaling via exchange protein activated by cAMP (Epac) drives the mobilization of reserve pool vesicles during post-tetanic potentiation (PTP). We discover that Rap1 couples activation of Rut-cAMP-Epac signaling to Vav-mediated synaptic potentiation. These findings indicate that Rap1 acts as an essential, convergent node for Abelson kinase and cAMP signaling to mediate BMP-induced structural plasticity and activity-induced functional plasticity via Vav-dependent regulation of the presynaptic actin cytoskeleton.
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Affiliation(s)
- Yeongjin David Kim
- Department of Brain and Cognitive Sciences, Seoul National University, Seoul, Korea
| | - Hyun Gwan Park
- Department of Brain and Cognitive Sciences, Seoul National University, Seoul, Korea
| | - Seunghwan Song
- Interdisciplinary Program in Neuroscience, Seoul National University, Seoul, Korea
| | - Joohyung Kim
- Department of Cell and Developmental Biology and Dental Research Institute, Seoul National University, Seoul, Korea
| | - Byoung Ju Lee
- Department of Cell and Developmental Biology and Dental Research Institute, Seoul National University, Seoul, Korea
| | - Kendal Broadie
- Departments of Cell and Developmental Biology, Pharmacology, and Biological Sciences, Vanderbilt University and Medical Center, Nashville, TN, USA
| | - Seungbok Lee
- Department of Brain and Cognitive Sciences, Seoul National University, Seoul, Korea
- Interdisciplinary Program in Neuroscience, Seoul National University, Seoul, Korea
- Department of Cell and Developmental Biology and Dental Research Institute, Seoul National University, Seoul, Korea
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2
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Dominicci-Cotto C, Vazquez M, Marie B. The Wingless planar cell polarity pathway is essential for optimal activity-dependent synaptic plasticity. Front Synaptic Neurosci 2024; 16:1322771. [PMID: 38633293 PMCID: PMC11021733 DOI: 10.3389/fnsyn.2024.1322771] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2023] [Accepted: 03/18/2024] [Indexed: 04/19/2024] Open
Abstract
From fly to man, the Wingless (Wg)/Wnt signaling molecule is essential for both the stability and plasticity of the nervous system. The Drosophila neuromuscular junction (NMJ) has proven to be a useful system for deciphering the role of Wg in directing activity-dependent synaptic plasticity (ADSP), which, in the motoneuron, has been shown to be dependent on both the canonical and the noncanonical calcium Wg pathways. Here we show that the noncanonical planar cell polarity (PCP) pathway is an essential component of the Wg signaling system controlling plasticity at the motoneuron synapse. We present evidence that disturbing the PCP pathway leads to a perturbation in ADSP. We first show that a PCP-specific allele of disheveled (dsh) affects the de novo synaptic structures produced during ADSP. We then show that the Rho GTPases downstream of Dsh in the PCP pathway are also involved in regulating the morphological changes that take place after repeated stimulation. Finally, we show that Jun kinase is essential for this phenomenon, whereas we found no indication of the involvement of the transcription factor complex AP1 (Jun/Fos). This work shows the involvement of the neuronal PCP signaling pathway in supporting ADSP. Because we find that AP1 mutants can perform ADSP adequately, we hypothesize that, upon Wg activation, the Rho GTPases and Jun kinase are involved locally at the synapse, in instructing cytoskeletal dynamics responsible for the appearance of the morphological changes occurring during ADSP.
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Affiliation(s)
- Carihann Dominicci-Cotto
- Department of Anatomy and Neurobiology, Medical Sciences Campus, University of Puerto Rico, San Juan, PR, United States
- Institute of Neurobiology, Medical Sciences Campus, University of Puerto Rico, San Juan, PR, United States
| | - Mariam Vazquez
- Institute of Neurobiology, Medical Sciences Campus, University of Puerto Rico, San Juan, PR, United States
- Molecular Sciences Research Center, University of Puerto Rico, San Juan, PR, United States
| | - Bruno Marie
- Department of Anatomy and Neurobiology, Medical Sciences Campus, University of Puerto Rico, San Juan, PR, United States
- Institute of Neurobiology, Medical Sciences Campus, University of Puerto Rico, San Juan, PR, United States
- Molecular Sciences Research Center, University of Puerto Rico, San Juan, PR, United States
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3
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Viragh E, Asztalos L, Fenckova M, Szlanka T, Gyorgypal Z, Kovacs K, IntHout J, Cizek P, Konda M, Szucs E, Zvara A, Biro J, Csapo E, Lukacsovich T, Hegedus Z, Puskas L, Schenck A, Asztalos Z. Pre-Pulse Inhibition of an escape response in adult fruit fly, Drosophila melanogaster. RESEARCH SQUARE 2024:rs.3.rs-3853873. [PMID: 38343805 PMCID: PMC10854311 DOI: 10.21203/rs.3.rs-3853873/v1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Indexed: 02/19/2024]
Abstract
Pre-Pulse Inhibition (PPI) is a neural process where suppression of a startle response is elicited by preceding the startling stimulus (Pulse) with a weak, non-startling one (Pre-Pulse). Defective PPI is widely employed as a behavioural endophenotype in humans and mammalian disorder-relevant models for neuropsychiatric disorders. We have developed a user-friendly, semi-automated, high-throughput-compatible Drosophila light-off jump response PPI paradigm, with which we demonstrate that PPI, with similar parameters measured in mammals, exists in adults of this model organism. We report that Drosophila PPI is affected by reduced expression of Dysbindin and both reduced and increased expression of Nmdar1 (N-methyl-D-aspartate receptor 1), perturbations associated with schizophrenia. Studying the biology of PPI in an organism that offers a plethora of genetic tools and a complex and well characterized connectome will greatly facilitate our efforts to gain deeper insight into the aetiology of human mental disorders, while reducing the need for mammalian models.
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Affiliation(s)
- Erika Viragh
- Institute of Biochemistry, HUN-REN Biological Research Centre, Szeged, Hungary
- Aktogen Hungary Ltd., Szeged, Hungary
| | - Lenke Asztalos
- Aktogen Hungary Ltd., Szeged, Hungary
- Aktogen Ltd., Department of Genetics, University of Cambridge, Cambridge, United Kingdom; Current address: Aktogen Ltd. Ramsey, Huntingdon, United Kingdom
| | - Michaela Fenckova
- Department of Human Genetics, Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center, Nijmegen, the Netherlands
- Department of Molecular Biology and Genetics, Faculty of Science, University of South Bohemia in Ceske Budejovice, Ceske Budejovice, Czechia
| | - Tamas Szlanka
- Institute of Biochemistry, HUN-REN Biological Research Centre, Szeged, Hungary
- Aktogen Hungary Ltd., Szeged, Hungary
| | - Zoltan Gyorgypal
- Institute of Biophysics & Core Facilities, HUN-REN Biological Research Centre, Szeged, Hungary
| | - Karoly Kovacs
- Institute of Biochemistry, HUN-REN Biological Research Centre, Szeged, Hungary
- HCEMM-BRC Metabolic Systems Biology Lab, Szeged, Hungary
| | - Joanna IntHout
- Department for Health Evidence (HEV), Radboud University Medical Center, Nijmegen, The Netherlands
| | - Pavel Cizek
- Department of Human Genetics, Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center, Nijmegen, the Netherlands
| | - Mihaly Konda
- Aktogen Hungary Ltd., Szeged, Hungary
- Voalaz Ltd., Szeged, Hungary
| | | | - Agnes Zvara
- Laboratory of Functional Genomics, HUN-REN Biological Research Centre Szeged, Hungary
| | | | | | | | - Zoltan Hegedus
- Institute of Biophysics & Core Facilities, HUN-REN Biological Research Centre, Szeged, Hungary
| | - Laszlo Puskas
- Laboratory of Functional Genomics, HUN-REN Biological Research Centre Szeged, Hungary
| | - Annette Schenck
- Department of Human Genetics, Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center, Nijmegen, the Netherlands
| | - Zoltan Asztalos
- Institute of Biochemistry, HUN-REN Biological Research Centre, Szeged, Hungary
- Aktogen Hungary Ltd., Szeged, Hungary
- Aktogen Ltd., Department of Genetics, University of Cambridge, Cambridge, United Kingdom; Current address: Aktogen Ltd. Ramsey, Huntingdon, United Kingdom
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4
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Pang B, Wu X, Chen H, Yan Y, Du Z, Yu Z, Yang X, Wang W, Lu K. Exploring the memory: existing activity-dependent tools to tag and manipulate engram cells. Front Cell Neurosci 2024; 17:1279032. [PMID: 38259503 PMCID: PMC10800721 DOI: 10.3389/fncel.2023.1279032] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2023] [Accepted: 10/17/2023] [Indexed: 01/24/2024] Open
Abstract
The theory of engrams, proposed several years ago, is highly crucial to understanding the progress of memory. Although it significantly contributes to identifying new treatments for cognitive disorders, it is limited by a lack of technology. Several scientists have attempted to validate this theory but failed. With the increasing availability of activity-dependent tools, several researchers have found traces of engram cells. Activity-dependent tools are based on the mechanisms underlying neuronal activity and use a combination of emerging molecular biological and genetic technology. Scientists have used these tools to tag and manipulate engram neurons and identified numerous internal connections between engram neurons and memory. In this review, we provide the background, principles, and selected examples of applications of existing activity-dependent tools. Using a combination of traditional definitions and concepts of engram cells, we discuss the applications and limitations of these tools and propose certain developmental directions to further explore the functions of engram cells.
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Affiliation(s)
- Bo Pang
- The Second Clinical Medical College, Southern Medical University, Guangzhou, China
| | - Xiaoyan Wu
- The First Clinical Medical College, Southern Medical University, Guangzhou, China
| | - Hailun Chen
- The Second Clinical Medical College, Southern Medical University, Guangzhou, China
| | - Yiwen Yan
- School of Basic Medicine Science, Southern Medical University, Guangzhou, China
| | - Zibo Du
- The First Clinical Medical College, Southern Medical University, Guangzhou, China
| | - Zihan Yu
- School of Basic Medicine Science, Southern Medical University, Guangzhou, China
| | - Xiai Yang
- Department of Neurology, Ankang Central Hospital, Ankang, China
| | - Wanshan Wang
- Laboratory Animal Management Center, Southern Medical University, Guangzhou, China
- Guangzhou Southern Medical Laboratory Animal Sci. and Tech. Co., Ltd., Guangzhou, China
| | - Kangrong Lu
- NMPA Key Laboratory for Safety Evaluation of Cosmetics, Southern Medical University, Guangzhou, China
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5
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Kozlov EN, Deev RV, Tokmatcheva EV, Tvorogova A, Kachaev ZM, Gilmutdinov RA, Zhukova M, Savvateeva-Popova EV, Schedl P, Shidlovskii YV. 3'UTR of mRNA Encoding CPEB Protein Orb2 Plays an Essential Role in Intracellular Transport in Neurons. Cells 2023; 12:1717. [PMID: 37443751 PMCID: PMC10340461 DOI: 10.3390/cells12131717] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2023] [Revised: 06/16/2023] [Accepted: 06/20/2023] [Indexed: 07/15/2023] Open
Abstract
Intracellular trafficking plays a critical role in the functioning of highly polarized cells, such as neurons. Transport of mRNAs, proteins, and other molecules to synaptic terminals maintains contact between neurons and ensures the transmission of nerve impulses. Cytoplasmic polyadenylation element binding (CPEB) proteins play an essential role in long-term memory (LTM) formation by regulating local translation in synapses. Here, we show that the 3'UTR of the Drosophila CPEB gene orb2 is required for targeting the orb2 mRNA and protein to synapses and that this localization is important for LTM formation. When the orb2 3'UTR is deleted, the orb2 mRNAs and proteins fail to localize in synaptic fractions, and pronounced LTM deficits arise. We found that the phenotypic effects of the orb2 3'UTR deletion were rescued by introducing the 3'UTR from the orb, another Drosophila CPEB gene. In contrast, the phenotypic effects of the 3'UTR deletion were not rescued by the 3'UTR from one of the Drosophila α-tubulin genes. Our results show that the orb2 mRNAs must be targeted to the correct locations in neurons and that proper targeting depends upon sequences in the 3'UTR.
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Affiliation(s)
- Eugene N. Kozlov
- Laboratory of Gene Expression Regulation in Development, Institute of Gene Biology, Russian Academy of Sciences, 119334 Moscow, Russia; (E.N.K.); (R.V.D.); (Z.M.K.); (R.A.G.); (M.Z.); (P.S.)
| | - Roman V. Deev
- Laboratory of Gene Expression Regulation in Development, Institute of Gene Biology, Russian Academy of Sciences, 119334 Moscow, Russia; (E.N.K.); (R.V.D.); (Z.M.K.); (R.A.G.); (M.Z.); (P.S.)
| | - Elena V. Tokmatcheva
- Institute of Physiology, Russian Academy of Sciences, 188680 St. Petersburg, Russia; (E.V.T.); (E.V.S.-P.)
| | - Anna Tvorogova
- Center for Precision Genome Editing and Genetic Technologies for Biomedicine, Institute of Gene Biology, Russian Academy of Sciences, 119334 Moscow, Russia;
| | - Zaur M. Kachaev
- Laboratory of Gene Expression Regulation in Development, Institute of Gene Biology, Russian Academy of Sciences, 119334 Moscow, Russia; (E.N.K.); (R.V.D.); (Z.M.K.); (R.A.G.); (M.Z.); (P.S.)
| | - Rudolf A. Gilmutdinov
- Laboratory of Gene Expression Regulation in Development, Institute of Gene Biology, Russian Academy of Sciences, 119334 Moscow, Russia; (E.N.K.); (R.V.D.); (Z.M.K.); (R.A.G.); (M.Z.); (P.S.)
| | - Mariya Zhukova
- Laboratory of Gene Expression Regulation in Development, Institute of Gene Biology, Russian Academy of Sciences, 119334 Moscow, Russia; (E.N.K.); (R.V.D.); (Z.M.K.); (R.A.G.); (M.Z.); (P.S.)
| | - Elena V. Savvateeva-Popova
- Institute of Physiology, Russian Academy of Sciences, 188680 St. Petersburg, Russia; (E.V.T.); (E.V.S.-P.)
| | - Paul Schedl
- Laboratory of Gene Expression Regulation in Development, Institute of Gene Biology, Russian Academy of Sciences, 119334 Moscow, Russia; (E.N.K.); (R.V.D.); (Z.M.K.); (R.A.G.); (M.Z.); (P.S.)
- Department of Molecular Biology, Princeton University, Princeton, NJ 08544-1014, USA
| | - Yulii V. Shidlovskii
- Laboratory of Gene Expression Regulation in Development, Institute of Gene Biology, Russian Academy of Sciences, 119334 Moscow, Russia; (E.N.K.); (R.V.D.); (Z.M.K.); (R.A.G.); (M.Z.); (P.S.)
- Department of Biology and General Genetics, Sechenov First Moscow State Medical University (Sechenov University), 119992 Moscow, Russia
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6
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Fernandes AR, Martins JP, Gomes ER, Mendes CS, Teodoro RO. Drosophila motor neuron boutons remodel through membrane blebbing coupled with muscle contraction. Nat Commun 2023; 14:3352. [PMID: 37291089 PMCID: PMC10250368 DOI: 10.1038/s41467-023-38421-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2021] [Accepted: 04/26/2023] [Indexed: 06/10/2023] Open
Abstract
Wired neurons form new presynaptic boutons in response to increased synaptic activity, however the mechanism(s) by which this occurs remains uncertain. Drosophila motor neurons (MNs) have clearly discernible boutons that display robust structural plasticity, being therefore an ideal system in which to study activity-dependent bouton genesis. Here, we show that in response to depolarization and in resting conditions, MNs form new boutons by membrane blebbing, a pressure-driven mechanism that occurs in 3-D cell migration, but to our knowledge not previously described to occur in neurons. Accordingly, F-actin is decreased in boutons during outgrowth, and non-muscle myosin-II is dynamically recruited to newly formed boutons. Furthermore, muscle contraction plays a mechanical role, which we hypothesize promotes bouton addition by increasing MN confinement. Overall, we identified a mechanism by which established circuits form new boutons allowing their structural expansion and plasticity, using trans-synaptic physical forces as the main driving force.
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Affiliation(s)
- Andreia R Fernandes
- iNOVA4Health, NOVA Medical School|Faculdade de Ciências Médicas, NMS|FCM, Universidade Nova de Lisboa, Lisboa, Portugal
| | - João P Martins
- iNOVA4Health, NOVA Medical School|Faculdade de Ciências Médicas, NMS|FCM, Universidade Nova de Lisboa, Lisboa, Portugal
- Instituto de Medicina Molecular João Lobo Antunes, Faculdade de Medicina da Universidade de Lisboa, Avenida Professor Egas Moniz, 1649-028, Lisboa, Portugal
| | - Edgar R Gomes
- Instituto de Medicina Molecular João Lobo Antunes, Faculdade de Medicina da Universidade de Lisboa, Avenida Professor Egas Moniz, 1649-028, Lisboa, Portugal
| | - César S Mendes
- iNOVA4Health, NOVA Medical School|Faculdade de Ciências Médicas, NMS|FCM, Universidade Nova de Lisboa, Lisboa, Portugal
| | - Rita O Teodoro
- iNOVA4Health, NOVA Medical School|Faculdade de Ciências Médicas, NMS|FCM, Universidade Nova de Lisboa, Lisboa, Portugal.
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7
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Gugel ZV, Maurais EG, Hong EJ. Chronic exposure to odors at naturally occurring concentrations triggers limited plasticity in early stages of Drosophila olfactory processing. eLife 2023; 12:e85443. [PMID: 37195027 PMCID: PMC10229125 DOI: 10.7554/elife.85443] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2022] [Accepted: 02/06/2023] [Indexed: 05/18/2023] Open
Abstract
In insects and mammals, olfactory experience in early life alters olfactory behavior and function in later life. In the vinegar fly Drosophila, flies chronically exposed to a high concentration of a monomolecular odor exhibit reduced behavioral aversion to the familiar odor when it is reencountered. This change in olfactory behavior has been attributed to selective decreases in the sensitivity of second-order olfactory projection neurons (PNs) in the antennal lobe that respond to the overrepresented odor. However, since odorant compounds do not occur at similarly high concentrations in natural sources, the role of odor experience-dependent plasticity in natural environments is unclear. Here, we investigated olfactory plasticity in the antennal lobe of flies chronically exposed to odors at concentrations that are typically encountered in natural odor sources. These stimuli were chosen to each strongly and selectively excite a single class of primary olfactory receptor neuron (ORN), thus facilitating a rigorous assessment of the selectivity of olfactory plasticity for PNs directly excited by overrepresented stimuli. Unexpectedly, we found that chronic exposure to three such odors did not result in decreased PN sensitivity but rather mildly increased responses to weak stimuli in most PN types. Odor-evoked PN activity in response to stronger stimuli was mostly unaffected by odor experience. When present, plasticity was observed broadly in multiple PN types and thus was not selective for PNs receiving direct input from the chronically active ORNs. We further investigated the DL5 olfactory coding channel and found that chronic odor-mediated excitation of its input ORNs did not affect PN intrinsic properties, local inhibitory innervation, ORN responses or ORN-PN synaptic strength; however, broad-acting lateral excitation evoked by some odors was increased. These results show that PN odor coding is only mildly affected by strong persistent activation of a single olfactory input, highlighting the stability of early stages of insect olfactory processing to significant perturbations in the sensory environment.
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Affiliation(s)
- Zhannetta V Gugel
- Division of Biology and Biological Engineering, California Institute of TechnologyPasadenaUnited States
| | - Elizabeth G Maurais
- Division of Biology and Biological Engineering, California Institute of TechnologyPasadenaUnited States
| | - Elizabeth J Hong
- Division of Biology and Biological Engineering, California Institute of TechnologyPasadenaUnited States
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8
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Shekhar S, Moehlman AT, Park B, Ewnetu M, Tracy C, Titos I, Pawłowski K, Tagliabracci VS, Krämer H. Allnighter pseudokinase-mediated feedback links proteostasis and sleep in Drosophila. Nat Commun 2023; 14:2932. [PMID: 37217484 DOI: 10.1038/s41467-023-38485-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2022] [Accepted: 05/04/2023] [Indexed: 05/24/2023] Open
Abstract
In nervous systems, retrograde signals are key for organizing circuit activity and maintaining neuronal homeostasis. We identify the conserved Allnighter (Aln) pseudokinase as a cell non-autonomous regulator of proteostasis responses necessary for normal sleep and structural plasticity of Drosophila photoreceptors. In aln mutants exposed to extended ambient light, proteostasis is dysregulated and photoreceptors develop striking, but reversible, dysmorphology. The aln gene is widely expressed in different neurons, but not photoreceptors. However, secreted Aln protein is retrogradely endocytosed by photoreceptors. Inhibition of photoreceptor synaptic release reduces Aln levels in lamina neurons, consistent with secreted Aln acting in a feedback loop. In addition, aln mutants exhibit reduced night time sleep, providing a molecular link between dysregulated proteostasis and sleep, two characteristics of ageing and neurodegenerative diseases.
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Affiliation(s)
- Shashank Shekhar
- Department of Neuroscience, UT Southwestern Medical Center, Dallas, TX; O'Donnell Brain Institute, Dallas, USA.
| | - Andrew T Moehlman
- Department of Neuroscience, UT Southwestern Medical Center, Dallas, TX; O'Donnell Brain Institute, Dallas, USA
- Surgical Neurology Branch, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, USA
| | - Brenden Park
- Department of Molecular Biology UT Southwestern Medical Center, Dallas, TX, USA
| | - Michael Ewnetu
- Department of Neuroscience, UT Southwestern Medical Center, Dallas, TX; O'Donnell Brain Institute, Dallas, USA
| | - Charles Tracy
- Department of Neuroscience, UT Southwestern Medical Center, Dallas, TX; O'Donnell Brain Institute, Dallas, USA
| | - Iris Titos
- Molecular Medicine Program, University of Utah, School of Medicine, Salt Lake City, UT, USA
| | - Krzysztof Pawłowski
- Department of Molecular Biology UT Southwestern Medical Center, Dallas, TX, USA
- Department of Biochemistry and Microbiology, Institute of Biology, Warsaw University of Life Sciences, Warsaw, 02-776, Poland
| | - Vincent S Tagliabracci
- Department of Molecular Biology UT Southwestern Medical Center, Dallas, TX, USA
- Howard Hughes Medical Institute, Maryland, USA
| | - Helmut Krämer
- Department of Neuroscience, UT Southwestern Medical Center, Dallas, TX; O'Donnell Brain Institute, Dallas, USA.
- Department of Cell Biology, UT Southwestern Medical Center, Dallas, TX, USA.
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9
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Osaka J, Yasuda H, Watanuki Y, Kato Y, Nitta Y, Sugie A, Sato M, Suzuki T. Identification of genes regulating stimulus-dependent synaptic assembly in Drosophila using an automated synapse quantification system. Genes Genet Syst 2023; 97:297-309. [PMID: 36878557 DOI: 10.1266/ggs.22-00114] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/06/2023] Open
Abstract
Neural activity-dependent synaptic plasticity is an important physiological phenomenon underlying environmental adaptation, memory and learning. However, its molecular basis, especially in presynaptic neurons, is not well understood. Previous studies have shown that the number of presynaptic active zones in the Drosophila melanogaster photoreceptor R8 is reversibly changed in an activity-dependent manner. During reversible synaptic changes, both synaptic disassembly and assembly processes were observed. Although we have established a paradigm for screening molecules involved in synaptic stability and several genes have been identified, genes involved in stimulus-dependent synaptic assembly are still elusive. Therefore, the aim of this study was to identify genes regulating stimulus-dependent synaptic assembly in Drosophila using an automated synapse quantification system. To this end, we performed RNAi screening against 300 memory-defective, synapse-related or transmembrane molecules in photoreceptor R8 neurons. Candidate genes were narrowed down to 27 genes in the first screen using presynaptic protein aggregation as a sign of synaptic disassembly. In the second screen, we directly quantified the decreasing synapse number using a GFP-tagged presynaptic protein marker. We utilized custom-made image analysis software, which automatically locates synapses and counts their number along individual R8 axons, and identified cirl as a candidate gene responsible for synaptic assembly. Finally, we present a new model of stimulus-dependent synaptic assembly through the interaction of cirl and its possible ligand, ten-a. This study demonstrates the feasibility of using the automated synapse quantification system to explore activity-dependent synaptic plasticity in Drosophila R8 photoreceptors in order to identify molecules involved in stimulus-dependent synaptic assembly.
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Affiliation(s)
- Jiro Osaka
- School of Life Science and Technology, Tokyo Institute of Technology
| | - Haruka Yasuda
- School of Life Science and Technology, Tokyo Institute of Technology
| | - Yusuke Watanuki
- School of Life Science and Technology, Tokyo Institute of Technology
| | - Yuya Kato
- School of Life Science and Technology, Tokyo Institute of Technology
| | - Yohei Nitta
- Brain Research Institute, Niigata University
| | | | - Makoto Sato
- Mathematical Neuroscience Unit, Institute for Frontier Science Initiative, Kanazawa University.,Graduate School of Frontier Science Initiative, Kanazawa University
| | - Takashi Suzuki
- School of Life Science and Technology, Tokyo Institute of Technology
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10
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Kozlov EN, Tokmatcheva EV, Khrustaleva AM, Grebenshchikov ES, Deev RV, Gilmutdinov RA, Lebedeva LA, Zhukova M, Savvateeva-Popova EV, Schedl P, Shidlovskii YV. Long-Term Memory Formation in Drosophila Depends on the 3'UTR of CPEB Gene orb2. Cells 2023; 12:cells12020318. [PMID: 36672258 PMCID: PMC9856895 DOI: 10.3390/cells12020318] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2022] [Revised: 12/30/2022] [Accepted: 01/12/2023] [Indexed: 01/18/2023] Open
Abstract
Activation of local translation in neurites in response to stimulation is an important step in the formation of long-term memory (LTM). CPEB proteins are a family of translation factors involved in LTM formation. The Drosophila CPEB protein Orb2 plays an important role in the development and function of the nervous system. Mutations of the coding region of the orb2 gene have previously been shown to impair LTM formation. We found that a deletion of the 3'UTR of the orb2 gene similarly results in loss of LTM in Drosophila. As a result of the deletion, the content of the Orb2 protein remained the same in the neuron soma, but significantly decreased in synapses. Using RNA immunoprecipitation followed by high-throughput sequencing, we detected more than 6000 potential Orb2 mRNA targets expressed in the Drosophila brain. Importantly, deletion of the 3'UTR of orb2 mRNA also affected the localization of the Csp, Pyd, and Eya proteins, which are encoded by putative mRNA targets of Orb2. Therefore, the 3'UTR of the orb2 mRNA is important for the proper localization of Orb2 and other proteins in synapses of neurons and the brain as a whole, providing a molecular basis for LTM formation.
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Affiliation(s)
- Eugene N. Kozlov
- Laboratory of Gene Expression Regulation in Development, Institute of Gene Biology, Russian Academy of Sciences, 119334 Moscow, Russia
| | - Elena V. Tokmatcheva
- Institute of Physiology, Russian Academy of Sciences, 188680 St. Petersburg, Russia
| | - Anastasia M. Khrustaleva
- Center for Precision Genome Editing and Genetic Technologies for Biomedicine, Institute of Gene Biology, Russian Academy of Sciences, 119334 Moscow, Russia
| | - Eugene S. Grebenshchikov
- Department of Biology and General Genetics, Sechenov First Moscow State Medical University (Sechenov University), 119992 Moscow, Russia
| | - Roman V. Deev
- Laboratory of Gene Expression Regulation in Development, Institute of Gene Biology, Russian Academy of Sciences, 119334 Moscow, Russia
| | - Rudolf A. Gilmutdinov
- Laboratory of Gene Expression Regulation in Development, Institute of Gene Biology, Russian Academy of Sciences, 119334 Moscow, Russia
| | - Lyubov A. Lebedeva
- Laboratory of Gene Expression Regulation in Development, Institute of Gene Biology, Russian Academy of Sciences, 119334 Moscow, Russia
| | - Mariya Zhukova
- Laboratory of Gene Expression Regulation in Development, Institute of Gene Biology, Russian Academy of Sciences, 119334 Moscow, Russia
| | | | - Paul Schedl
- Laboratory of Gene Expression Regulation in Development, Institute of Gene Biology, Russian Academy of Sciences, 119334 Moscow, Russia
- Department of Molecular Biology, Princeton University, Princeton University, Princeton, NJ 08544-1014, USA
| | - Yulii V. Shidlovskii
- Laboratory of Gene Expression Regulation in Development, Institute of Gene Biology, Russian Academy of Sciences, 119334 Moscow, Russia
- Department of Biology and General Genetics, Sechenov First Moscow State Medical University (Sechenov University), 119992 Moscow, Russia
- Correspondence:
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11
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Gold OMS, Bardsley EN, Ponnampalam AP, Pauza AG, Paton JFR. Cellular basis of learning and memory in the carotid body. Front Synaptic Neurosci 2022; 14:902319. [PMID: 36046221 PMCID: PMC9420943 DOI: 10.3389/fnsyn.2022.902319] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2022] [Accepted: 07/20/2022] [Indexed: 11/13/2022] Open
Abstract
The carotid body is the primary peripheral chemoreceptor in the body, and critical for respiration and cardiovascular adjustments during hypoxia. Yet considerable evidence now implicates the carotid body as a multimodal sensor, mediating the chemoreflexes of a wide range of physiological responses, including pH, temperature, and acidosis as well as hormonal, glucose and immune regulation. How does the carotid body detect and initiate appropriate physiological responses for these diverse stimuli? The answer to this may lie in the structure of the carotid body itself. We suggest that at an organ-level the carotid body is comparable to a miniature brain with compartmentalized discrete regions of clustered glomus cells defined by their neurotransmitter expression and receptor profiles, and with connectivity to defined reflex arcs that play a key role in initiating distinct physiological responses, similar in many ways to a switchboard that connects specific inputs to selective outputs. Similarly, within the central nervous system, specific physiological outcomes are co-ordinated, through signaling via distinct neuronal connectivity. As with the brain, we propose that highly organized cellular connectivity is critical for mediating co-ordinated outputs from the carotid body to a given stimulus. Moreover, it appears that the rudimentary components for synaptic plasticity, and learning and memory are conserved in the carotid body including the presence of glutamate and GABAergic systems, where evidence pinpoints that pathophysiology of common diseases of the carotid body may be linked to deviations in these processes. Several decades of research have contributed to our understanding of the central nervous system in health and disease, and we discuss that understanding the key processes involved in neuronal dysfunction and synaptic activity may be translated to the carotid body, offering new insights and avenues for therapeutic innovation.
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12
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Richard M, Doubková K, Nitta Y, Kawai H, Sugie A, Tavosanis G. A Quantitative Model of Sporadic Axonal Degeneration in the Drosophila Visual System. J Neurosci 2022; 42:4937-4952. [PMID: 35534228 PMCID: PMC9188428 DOI: 10.1523/jneurosci.2115-21.2022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2021] [Revised: 04/26/2022] [Accepted: 04/28/2022] [Indexed: 11/21/2022] Open
Abstract
In human neurodegenerative diseases, neurons undergo axonal degeneration months to years before they die. Here, we developed a system modeling early degenerative events in Drosophila adult photoreceptor cells. Thanks to the stereotypy of their axonal projections, this system delivers quantitative data on sporadic and progressive axonal degeneration of photoreceptor cells. Using this method, we show that exposure of adult female flies to a constant light stimulation for several days overcomes the intrinsic resilience of R7 photoreceptors and leads to progressive axonal degeneration. This was not associated with apoptosis. We furthermore provide evidence that loss of synaptic integrity between R7 and a postsynaptic partner preceded axonal degeneration, thus recapitulating features of human neurodegenerative diseases. Finally, our experiments uncovered a role of postsynaptic partners of R7 to initiate degeneration, suggesting that postsynaptic cells signal back to the photoreceptor to maintain axonal structure. This model can be used to dissect cellular and circuit mechanisms involved in the early events of axonal degeneration, allowing for a better understanding of how neurons cope with stress and lose their resilience capacities.SIGNIFICANCE STATEMENT Neurons can be active and functional for several years. In the course of aging and in disease conditions leading to neurodegeneration, subsets of neurons lose their resilience and start dying. What initiates this turning point at the cellular level is not clear. Here, we developed a model allowing to systematically describe this phase. The loss of synapses and axons represents an early and functionally relevant event toward degeneration. Using the ordered distribution of Drosophila photoreceptor axon terminals, we assembled a system to study sporadic initiation of axon loss and delineated a role for non-cell-autonomous activity regulation in the initiation of axon degeneration. This work will help shed light on key steps in the etiology of nonfamilial cases of neurodegenerative diseases.
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Affiliation(s)
- Mélisande Richard
- Deutsches Zentrum für Neurodegenerative Erkrankungen e. V., 53127 Bonn, Germany
| | - Karolína Doubková
- Deutsches Zentrum für Neurodegenerative Erkrankungen e. V., 53127 Bonn, Germany
| | - Yohei Nitta
- Brain Research Institute, Niigata University, Niigata 951-8585, Japan
| | | | - Atsushi Sugie
- Brain Research Institute, Niigata University, Niigata 951-8585, Japan
| | - Gaia Tavosanis
- Deutsches Zentrum für Neurodegenerative Erkrankungen e. V., 53127 Bonn, Germany
- Life & Medical Sciences Institute (LIMES), University of Bonn, 53115 Bonn, Germany
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13
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Liu KE, Raymond MH, Ravichandran KS, Kucenas S. Clearing Your Mind: Mechanisms of Debris Clearance After Cell Death During Neural Development. Annu Rev Neurosci 2022; 45:177-198. [PMID: 35226828 PMCID: PMC10157384 DOI: 10.1146/annurev-neuro-110920-022431] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Neurodevelopment and efferocytosis have fascinated scientists for decades. How an organism builds a nervous system that is precisely tuned for efficient behaviors and survival and how it simultaneously manages constant somatic cell turnover are complex questions that have resulted in distinct fields of study. Although neurodevelopment requires the overproduction of cells that are subsequently pruned back, very few studies marry these fields to elucidate the cellular and molecular mechanisms that drive nervous system development through the lens of cell clearance. In this review, we discuss these fields to highlight exciting areas of future synergy. We first review neurodevelopment from the perspective of overproduction and subsequent refinement and then discuss who clears this developmental debris and the mechanisms that control these events. We then end with how a more deliberate merger of neurodevelopment and efferocytosis could reframe our understanding of homeostasis and disease and discuss areas of future study. Expected final online publication date for the Annual Review of Neuroscience, Volume 45 is July 2022. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.
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Affiliation(s)
- Kendra E Liu
- Neuroscience Graduate Program, University of Virginia, Charlottesville, Virginia, USA; .,Program in Fundamental Neuroscience, University of Virginia, Charlottesville, Virginia, USA
| | - Michael H Raymond
- Neuroscience Graduate Program, University of Virginia, Charlottesville, Virginia, USA; .,Center for Clearance, University of Virginia, Charlottesville, Virginia, USA
| | - Kodi S Ravichandran
- Neuroscience Graduate Program, University of Virginia, Charlottesville, Virginia, USA; .,Center for Clearance, University of Virginia, Charlottesville, Virginia, USA.,Department of Microbiology, Immunology, and Cancer Biology, University of Virginia, Charlottesville, Virginia, USA.,VIB-UGent Center for Inflammation Research and the Department of Biomedical Molecular Biology, Ghent University, Ghent, Belgium
| | - Sarah Kucenas
- Neuroscience Graduate Program, University of Virginia, Charlottesville, Virginia, USA; .,Program in Fundamental Neuroscience, University of Virginia, Charlottesville, Virginia, USA.,Department of Biology, University of Virginia, Charlottesville, Virginia, USA
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14
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Bai Y, Suzuki T. Activity-dependent circuitry plasticity via the regulation of the histamine receptor level in the Drosophila visual system. Mol Cell Neurosci 2022; 119:103703. [PMID: 35122941 DOI: 10.1016/j.mcn.2022.103703] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2021] [Revised: 12/19/2021] [Accepted: 01/27/2022] [Indexed: 10/19/2022] Open
Abstract
Activity-dependent synaptic plasticity is crucial for responses to the environment. Although the plasticity mechanisms of presynaptic photoreceptor neurons in the Drosophila visual system have been well studied, postsynaptic modifications remain elusive. In addition, further studies on the adaption of the visual system to different light experiences at a circuitry scale are required. Using the modified transcriptional reporter of intracellular Ca2+ method, we describe a way to visualize circuitry changes according to different light experiences. We found enhanced postsynaptic neuronal activity responses in lamina monopolar neuron L2 after prolonged light treatment. Although L1 also has connections with photoreceptors, there were no enhanced activity responses in L1. We also report in this study that activity-dependent transcriptional downregulation of inhibitory histamine receptor (HR), Ort, occurs in postsynaptic neuron L2, but not in L1, during continuous light conditions. We produced exogenous Ort proteins in L2 neurons and found that it attenuated the enhanced activity response caused by constant light exposure. These findings, together with the fact that histamine is the main inhibitory neurotransmitter released by photoreceptors in the Drosophila visual system, confirmed our hypothesis that the activity-dependent transcriptional downregulation of HR is responsible for the constant light exposure-induced circuitry response changes in L2. The results successfully demonstrated the selective circuit change after synaptic remodeling evoked by long-term activation and provided in vivo evidence of circuitry plasticity upon long-term environmental stimulation.
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Affiliation(s)
- Yiming Bai
- Graduate School of Life Science and Technology, Tokyo Institute of Technology, Yokohama 226-0026, Japan
| | - Takashi Suzuki
- Graduate School of Life Science and Technology, Tokyo Institute of Technology, Yokohama 226-0026, Japan.
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15
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Maldonado-Díaz C, Vazquez M, Marie B. A comparison of three different methods of eliciting rapid activity-dependent synaptic plasticity at the Drosophila NMJ. PLoS One 2021; 16:e0260553. [PMID: 34847197 PMCID: PMC8631638 DOI: 10.1371/journal.pone.0260553] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2021] [Accepted: 11/11/2021] [Indexed: 11/29/2022] Open
Abstract
The Drosophila NMJ is a system of choice for investigating the mechanisms underlying the structural and functional modifications evoked during activity-dependent synaptic plasticity. Because fly genetics allows considerable versatility, many strategies can be employed to elicit this activity. Here, we compare three different stimulation methods for eliciting activity-dependent changes in structure and function at the Drosophila NMJ. We find that the method using patterned stimulations driven by a K+-rich solution creates robust structural modifications but reduces muscle viability, as assessed by resting potential and membrane resistance. We argue that, using this method, electrophysiological studies that consider the frequency of events, rather than their amplitude, are the only reliable studies. We contrast these results with the expression of CsChrimson channels and red-light stimulation at the NMJ, as well as with the expression of TRPA channels and temperature stimulation. With both these methods we observed reliable modifications of synaptic structures and consistent changes in electrophysiological properties. Indeed, we observed a rapid appearance of immature boutons that lack postsynaptic differentiation, and a potentiation of spontaneous neurotransmission frequency. Surprisingly, a patterned application of temperature changes alone is sufficient to provoke both structural and functional plasticity. In this context, temperature-dependent TRPA channel activation induces additional structural plasticity but no further increase in the frequency of spontaneous neurotransmission, suggesting an uncoupling of these mechanisms.
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Affiliation(s)
- Carolina Maldonado-Díaz
- Institute of Neurobiology, University of Puerto Rico, Medical Sciences Campus, San Juan, Puerto Rico
- Department of Anatomy & Neurobiology, University of Puerto Rico, Medical Sciences Campus, San Juan, Puerto Rico
| | - Mariam Vazquez
- Institute of Neurobiology, University of Puerto Rico, Medical Sciences Campus, San Juan, Puerto Rico
| | - Bruno Marie
- Institute of Neurobiology, University of Puerto Rico, Medical Sciences Campus, San Juan, Puerto Rico
- Department of Anatomy & Neurobiology, University of Puerto Rico, Medical Sciences Campus, San Juan, Puerto Rico
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16
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Glinert A, Turjeman S, Elliott E, Koren O. Microbes, metabolites and (synaptic) malleability, oh my! The effect of the microbiome on synaptic plasticity. Biol Rev Camb Philos Soc 2021; 97:582-599. [PMID: 34734461 PMCID: PMC9298272 DOI: 10.1111/brv.12812] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2021] [Revised: 10/10/2021] [Accepted: 10/22/2021] [Indexed: 12/15/2022]
Abstract
The microbiome influences the emotional and cognitive phenotype of its host, as well as the neurodevelopment and pathophysiology of various brain processes and disorders, via the well‐established microbiome–gut–brain axis. Rapidly accumulating data link the microbiome to severe neuropsychiatric disorders in humans, including schizophrenia, Alzheimer's and Parkinson's. Moreover, preclinical work has shown that perturbation of the microbiome is closely associated with social, cognitive and behavioural deficits. The potential of the microbiome as a diagnostic and therapeutic tool is currently undercut by a lack of clear mechanistic understanding of the microbiome–gut–brain axis. This review establishes the hypothesis that the mechanism by which this influence is carried out is synaptic plasticity – long‐term changes to the physical and functional neuronal structures that enable the brain to undertake learning, memory formation, emotional regulation and more. By examining the different constituents of the microbiome–gut–brain axis through the lens of synaptic plasticity, this review explores the diverse aspects by which the microbiome shapes the behaviour and mental wellbeing of the host. Key elements of this complex bi‐directional relationship include neurotransmitters, neuronal electrophysiology, immune mediators that engage with both the central and enteric nervous systems and signalling cascades that trigger long‐term potentiation of synapses. The importance of establishing mechanistic correlations along the microbiome–gut–brain axis cannot be overstated as they hold the potential for furthering current understanding regarding the vast fields of neuroscience and neuropsychiatry. This review strives to elucidate the promising theory of microbiome‐driven synaptic plasticity in the hope of enlightening current researchers and inspiring future ones.
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Affiliation(s)
- Ayala Glinert
- Azrieli Faculty of Medicine, Bar Ilan University, 8 Henrietta Szold, Safed, 1311502, Israel
| | - Sondra Turjeman
- Azrieli Faculty of Medicine, Bar Ilan University, 8 Henrietta Szold, Safed, 1311502, Israel
| | - Evan Elliott
- Azrieli Faculty of Medicine, Bar Ilan University, 8 Henrietta Szold, Safed, 1311502, Israel
| | - Omry Koren
- Azrieli Faculty of Medicine, Bar Ilan University, 8 Henrietta Szold, Safed, 1311502, Israel
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17
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The Journal of Neuroscience's 40th Anniversary: Looking Back, Looking Forward. J Neurosci 2021; 41:4949-4953. [PMID: 33958487 DOI: 10.1523/jneurosci.0512-21.2021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2021] [Revised: 04/19/2021] [Accepted: 04/27/2021] [Indexed: 11/21/2022] Open
Abstract
Some of us fortunate enough to have published a paper in The Journal of Neuroscience in its inaugural year (1981) have been asked to write a Progressions article addressing our views on the significance of the original work and how ideas about the topic of that work have evolved over the last 40 years. These questions cannot be effectively considered without placing them in the context of the incredible growth of the overall field of neuroscience over these last four decades. For openers, in 1981, the Nobel Prize was awarded to three neuroscience superstars: Roger Sperry, David Hubel, and Torsten Wiesel. Not a bad year to launch the Journal With this as a backdrop, I divide this Progressions article into two parts. First, I discuss our original (1981) paper describing classical conditioning in Aplysia californica, and place our results in the context of the state of the field at the time. Second, I fast forward to the present and consider some of remarkable progress in the broad field of learning and memory that has occurred in the last 40 years. Along the way, I also reflect briefly on some of the amazing advances, both technical and conceptual, that we in neuroscience have witnessed.
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18
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Choi BJ, Chen YCD, Desplan C. Building a circuit through correlated spontaneous neuronal activity in the developing vertebrate and invertebrate visual systems. Genes Dev 2021; 35:677-691. [PMID: 33888564 PMCID: PMC8091978 DOI: 10.1101/gad.348241.121] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
During the development of the vertebrate nervous systems, genetic programs assemble an immature circuit that is subsequently refined by neuronal activity evoked by external stimuli. However, prior to sensory experience, the intrinsic property of the developing nervous system also triggers correlated network-level neuronal activity, with retinal waves in the developing vertebrate retina being the best documented example. Spontaneous activity has also been found in the visual system of Drosophila Here, we compare the spontaneous activity of the developing visual system between mammalian and Drosophila and suggest that Drosophila is an emerging model for mechanistic and functional studies of correlated spontaneous activity.
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Affiliation(s)
- Ben Jiwon Choi
- Department of Biology, New York University, New York, New York 10003, USA
| | | | - Claude Desplan
- Department of Biology, New York University, New York, New York 10003, USA
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19
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Aponte-Santiago NA, Littleton JT. Synaptic Properties and Plasticity Mechanisms of Invertebrate Tonic and Phasic Neurons. Front Physiol 2020; 11:611982. [PMID: 33391026 PMCID: PMC7772194 DOI: 10.3389/fphys.2020.611982] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2020] [Accepted: 11/24/2020] [Indexed: 12/15/2022] Open
Abstract
Defining neuronal cell types and their associated biophysical and synaptic diversity has become an important goal in neuroscience as a mechanism to create comprehensive brain cell atlases in the post-genomic age. Beyond broad classification such as neurotransmitter expression, interneuron vs. pyramidal, sensory or motor, the field is still in the early stages of understanding closely related cell types. In both vertebrate and invertebrate nervous systems, one well-described distinction related to firing characteristics and synaptic release properties are tonic and phasic neuronal subtypes. In vertebrates, these classes were defined based on sustained firing responses during stimulation (tonic) vs. transient responses that rapidly adapt (phasic). In crustaceans, the distinction expanded to include synaptic release properties, with tonic motoneurons displaying sustained firing and weaker synapses that undergo short-term facilitation to maintain muscle contraction and posture. In contrast, phasic motoneurons with stronger synapses showed rapid depression and were recruited for short bursts during fast locomotion. Tonic and phasic motoneurons with similarities to those in crustaceans have been characterized in Drosophila, allowing the genetic toolkit associated with this model to be used for dissecting the unique properties and plasticity mechanisms for these neuronal subtypes. This review outlines general properties of invertebrate tonic and phasic motoneurons and highlights recent advances that characterize distinct synaptic and plasticity pathways associated with two closely related glutamatergic neuronal cell types that drive invertebrate locomotion.
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Affiliation(s)
- Nicole A. Aponte-Santiago
- The Picower Institute for Learning and Memory, Department of Biology and Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, MA, United States
- Eli and Edythe Broad Center of Regeneration Medicine and Stem Cell Research, Department of Obstetrics, Gynecology and Reproductive Sciences, University of California, San Francisco, San Francisco, CA, United States
| | - J. Troy Littleton
- The Picower Institute for Learning and Memory, Department of Biology and Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, MA, United States
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20
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Rushton E, Kopke DL, Broadie K. Extracellular heparan sulfate proteoglycans and glycan-binding lectins orchestrate trans-synaptic signaling. J Cell Sci 2020; 133:133/15/jcs244186. [PMID: 32788209 DOI: 10.1242/jcs.244186] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
The exceedingly narrow synaptic cleft (<20 nm) and adjacent perisynaptic extracellular space contain an astonishing array of secreted and membrane-anchored glycoproteins. A number of these extracellular molecules regulate intercellular trans-synaptic signaling by binding to ligands, acting as co-receptors or modulating ligand-receptor interactions. Recent work has greatly expanded our understanding of extracellular proteoglycan and glycan-binding lectin families as key regulators of intercellular signaling at the synapse. These secreted proteins act to regulate the compartmentalization of glycoprotein ligands and receptors, crosslink dynamic extracellular and cell surface lattices, modulate both exocytosis and endocytosis vesicle cycling, and control postsynaptic receptor trafficking. Here, we focus closely on the Drosophila glutamatergic neuromuscular junction (NMJ) as a model synapse for understanding extracellular roles of the many heparan sulfate proteoglycan (HSPG) and lectin proteins that help determine synaptic architecture and neurotransmission strength. We particularly concentrate on the roles of extracellular HSPGs and lectins in controlling trans-synaptic signaling, especially that mediated by the Wnt and BMP pathways. These signaling mechanisms are causally linked to a wide spectrum of neurological disease states that impair coordinated movement and cognitive functions.
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Affiliation(s)
- Emma Rushton
- Department of Biological Sciences, Brain Institute, and Kennedy Center for Research on Human Development, Vanderbilt University, Nashville, TN 37235, USA
| | - Danielle L Kopke
- Department of Biological Sciences, Brain Institute, and Kennedy Center for Research on Human Development, Vanderbilt University, Nashville, TN 37235, USA
| | - Kendal Broadie
- Department of Biological Sciences, Brain Institute, and Kennedy Center for Research on Human Development, Vanderbilt University, Nashville, TN 37235, USA
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21
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Véras JH, do Vale CR, da Silva Lima DC, dos Anjos MM, Bernardes A, de Moraes Filho AV, e Silva CR, de Oliveira GR, Pérez CN, Chen-Chen L. Modulating effect of a hydroxychalcone and a novel coumarin–chalcone hybrid against mitomycin-induced genotoxicity in somatic cells of Drosophila melanogaster. Drug Chem Toxicol 2020; 45:775-784. [DOI: 10.1080/01480545.2020.1776314] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Affiliation(s)
- Jefferson Hollanda Véras
- Laboratory of Radiobiology and Mutagenesis, Department of Genetics, Institute of Biological Sciences, Universidade Federal de Goiás, Goiânia, Brazil
| | - Camila Regina do Vale
- Laboratory of Radiobiology and Mutagenesis, Department of Genetics, Institute of Biological Sciences, Universidade Federal de Goiás, Goiânia, Brazil
| | - Débora Cristina da Silva Lima
- Laboratory of Radiobiology and Mutagenesis, Department of Genetics, Institute of Biological Sciences, Universidade Federal de Goiás, Goiânia, Brazil
| | | | - Aline Bernardes
- Chemistry Institute, Universidade Federal de Goiás, Goiânia, Brazil
| | - Aroldo Vieira de Moraes Filho
- Laboratory of Radiobiology and Mutagenesis, Department of Genetics, Institute of Biological Sciences, Universidade Federal de Goiás, Goiânia, Brazil
| | - Carolina Ribeiro e Silva
- Laboratory of Radiobiology and Mutagenesis, Department of Genetics, Institute of Biological Sciences, Universidade Federal de Goiás, Goiânia, Brazil
| | | | | | - Lee Chen-Chen
- Laboratory of Radiobiology and Mutagenesis, Department of Genetics, Institute of Biological Sciences, Universidade Federal de Goiás, Goiânia, Brazil
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