1
|
Zheng A, Schmid S. A review of the neural basis underlying the acoustic startle response with a focus on recent developments in mammals. Neurosci Biobehav Rev 2023; 148:105129. [PMID: 36914078 DOI: 10.1016/j.neubiorev.2023.105129] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2023] [Revised: 03/07/2023] [Accepted: 03/10/2023] [Indexed: 03/13/2023]
Abstract
The startle response consists of whole-body muscle contractions, eye-blink, accelerated heart rate, and freezing in response to a strong, sudden stimulus. It is evolutionarily preserved and can be observed in any animal that can perceive sensory signals, indicating the important protective function of startle. Startle response measurements and its alterations have become a valuable tool for exploring sensorimotor processes and sensory gating, especially in the context of pathologies of psychiatric disorders. The last reviews on the neural substrates underlying acoustic startle were published around 20 years ago. Advancements in methods and techniques have since allowed new insights into acoustic startle mechanisms. This review is focused on the neural circuitry that drives the primary acoustic startle response in mammals. However, there have also been very successful efforts to identify the acoustic startle pathway in other vertebrates and invertebrates in the past decades, so at the end we briefly summarize these studies and comment on the similarities and differences between species.
Collapse
Affiliation(s)
- Alice Zheng
- Department of Anatomy and Cell Biology, Schulich School of Medicine & Dentistry, University of Western Ontario, Canada
| | - Susanne Schmid
- Department of Anatomy and Cell Biology, Schulich School of Medicine & Dentistry, University of Western Ontario, Canada.
| |
Collapse
|
2
|
Burton EA, Burgess HA. A Critical Review of Zebrafish Neurological Disease Models-2. Application: Functional and Neuroanatomical Phenotyping Strategies and Chemical Screens. OXFORD OPEN NEUROSCIENCE 2022; 2:kvac019. [PMID: 37637775 PMCID: PMC10455049 DOI: 10.1093/oons/kvac019] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/02/2022] [Revised: 11/28/2022] [Indexed: 08/29/2023]
Abstract
Extensive phylogenetic conservation of molecular pathways and neuroanatomical structures, associated with efficient methods for genetic modification, have been exploited increasingly to generate zebrafish models of human disease. A range of powerful approaches can be deployed to analyze these models with the ultimate goal of elucidating pathogenic mechanisms and accelerating efforts to find effective treatments. Unbiased neurobehavioral assays can provide readouts that parallel clinical abnormalities found in patients, although some of the most useful assays quantify responses that are not routinely evaluated clinically, and differences between zebrafish and human brains preclude expression of the full range of neurobehavioral abnormalities seen in disease. Imaging approaches that use fluorescent reporters and standardized brain atlases coupled with quantitative measurements of brain structure offer an unbiased means to link experimental manipulations to changes in neural architecture. Together, quantitative structural and functional analyses allow dissection of the cellular and physiological basis underlying neurological phenotypes. These approaches can be used as outputs in chemical modifier screens, which provide a major opportunity to exploit zebrafish models to identify small molecule modulators of pathophysiology that may be informative for understanding disease mechanisms and possible therapeutic approaches.
Collapse
Affiliation(s)
- Edward A Burton
- Pittsburgh Institute of Neurodegenerative Diseases, University of Pittsburgh, Pittsburgh, PA 15260, USA
- Department of Neurology, University of Pittsburgh, Pittsburgh, PA 15260, USA
- Geriatric Research, Education, and Clinical Center, Pittsburgh VA Healthcare System, Pittsburgh, PA 15240, USA
| | - Harold A Burgess
- Division of Developmental Biology, Eunice Kennedy Shriver National Institute of Child Health and Human Development, Bethesda, MD 20892, USA
| |
Collapse
|
3
|
Ogura Y, Uehara T, Ujibe K, Yoshihashi H, Yamada M, Suzuki H, Takenouchi T, Kosaki K, Hirata H. The p.Thr395Met missense variant of NFIA found in a patient with intellectual disability is a defective variant. Am J Med Genet A 2022; 188:1184-1192. [PMID: 35018717 DOI: 10.1002/ajmg.a.62638] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2021] [Revised: 12/05/2021] [Accepted: 12/11/2021] [Indexed: 12/17/2022]
Abstract
Nuclear factor one A (NFIA) is a transcription factor that regulates the development of the central nervous system. Haploinsufficiency of the NFIA gene causes NFIA-related disorder, which includes brain abnormalities and intellectual disability, with or without urinary tract defects. Intragenic deletions, nonsense variants, frameshift variants, and missense variants in one allele of the NFIA gene have been reported to cause various neurological and urogenital symptoms. Here we report a 10-year-old male patient with developmental delay, coarctation of the aorta, and distinctive facial features. Exome analysis identified a rare de novo heterozygous missense variant p.Thr395Met in NFIA. We employed zebrafish as a model organism in our NFIA analysis and found that nfia-/- zebrafish initially showed a loss of commissural axons in the brain, and eventually underwent growth retardation resulting in premature death. Impairment of the commissural neurons in nfia-/- zebrafish embryos could be restored by the expression of wild-type human NFIA protein, but not of mutant human protein harboring the p.Thr395Met substitution, indicating that this variant affects the function of NFIA protein. Taken together, we suggest that the p.Thr395Met allele in the NFIA gene is relevant to the pathogenesis of NFIA-related disorder.
Collapse
Affiliation(s)
- Yurie Ogura
- Department of Chemistry and Biological Science, College of Science and Engineering, Aoyama Gakuin University, Sagamihara, Japan
| | - Tomoko Uehara
- Center for Medical Genetics, Keio University School of Medicine, Tokyo, Japan.,Department of Clinical Genetics, Aichi Developmental Disability Center Central Hospital, Aichi, Japan
| | - Kota Ujibe
- Department of Chemistry and Biological Science, College of Science and Engineering, Aoyama Gakuin University, Sagamihara, Japan
| | - Hiroshi Yoshihashi
- Department of Clinical Genetics, Tokyo Metropolitan Children's Medical Center, Tokyo, Japan
| | - Mamiko Yamada
- Center for Medical Genetics, Keio University School of Medicine, Tokyo, Japan
| | - Hisato Suzuki
- Center for Medical Genetics, Keio University School of Medicine, Tokyo, Japan
| | - Toshiki Takenouchi
- Department of Pediatrics, Keio University School of Medicine, Tokyo, Japan
| | - Kenjiro Kosaki
- Center for Medical Genetics, Keio University School of Medicine, Tokyo, Japan
| | - Hiromi Hirata
- Department of Chemistry and Biological Science, College of Science and Engineering, Aoyama Gakuin University, Sagamihara, Japan
| |
Collapse
|
4
|
The presynaptic glycine transporter GlyT2 is regulated by the Hedgehog pathway in vitro and in vivo. Commun Biol 2021; 4:1197. [PMID: 34663888 PMCID: PMC8523746 DOI: 10.1038/s42003-021-02718-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2020] [Accepted: 09/22/2021] [Indexed: 01/20/2023] Open
Abstract
The identity of a glycinergic synapse is maintained presynaptically by the activity of a surface glycine transporter, GlyT2, which recaptures glycine back to presynaptic terminals to preserve vesicular glycine content. GlyT2 loss-of-function mutations cause Hyperekplexia, a rare neurological disease in which loss of glycinergic neurotransmission causes generalized stiffness and strong motor alterations. However, the molecular underpinnings controlling GlyT2 activity remain poorly understood. In this work, we identify the Hedgehog pathway as a robust controller of GlyT2 expression and transport activity. Modulating the activation state of the Hedgehog pathway in vitro in rodent primary spinal cord neurons or in vivo in zebrafish embryos induced a selective control in GlyT2 expression, regulating GlyT2 transport activity. Our results indicate that activation of Hedgehog reduces GlyT2 expression by increasing its ubiquitination and degradation. This work describes a new molecular link between the Hedgehog signaling pathway and presynaptic glycine availability. By modulating the activation state of the Hedgehog pathway, de la Rocha-Muñoz et al demonstrate that Hedgehog signaling controls the expression and transport activity of the neuronal glycine transporter GlyT2. This work begins to reveal a potential link between the Hedgehog signaling pathway and presynaptic glycine availability.
Collapse
|
5
|
Meserve JH, Nelson JC, Marsden KC, Hsu J, Echeverry FA, Jain RA, Wolman MA, Pereda AE, Granato M. A forward genetic screen identifies Dolk as a regulator of startle magnitude through the potassium channel subunit Kv1.1. PLoS Genet 2021; 17:e1008943. [PMID: 34061829 PMCID: PMC8195410 DOI: 10.1371/journal.pgen.1008943] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2020] [Revised: 06/11/2021] [Accepted: 05/04/2021] [Indexed: 11/19/2022] Open
Abstract
The acoustic startle response is an evolutionarily conserved avoidance behavior. Disruptions in startle behavior, particularly startle magnitude, are a hallmark of several human neurological disorders. While the neural circuitry underlying startle behavior has been studied extensively, the repertoire of genes and genetic pathways that regulate this locomotor behavior has not been explored using an unbiased genetic approach. To identify such genes, we took advantage of the stereotypic startle behavior in zebrafish larvae and performed a forward genetic screen coupled with whole genome analysis. We uncovered mutations in eight genes critical for startle behavior, including two genes encoding proteins associated with human neurological disorders, Dolichol kinase (Dolk), a broadly expressed regulator of the glycoprotein biosynthesis pathway, and the potassium Shaker-like channel subunit Kv1.1. We demonstrate that Kv1.1 and Dolk play critical roles in the spinal cord to regulate movement magnitude during the startle response and spontaneous swim movements. Moreover, we show that Kv1.1 protein is mislocalized in dolk mutants, suggesting they act in a common genetic pathway. Combined, our results identify a diverse set of eight genes, all associated with human disorders, that regulate zebrafish startle behavior and reveal a previously unappreciated role for Dolk and Kv1.1 in regulating movement magnitude via a common genetic pathway.
Collapse
Affiliation(s)
- Joy H. Meserve
- Department of Cell and Developmental Biology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
| | - Jessica C. Nelson
- Department of Cell and Developmental Biology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
| | - Kurt C. Marsden
- Department of Cell and Developmental Biology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
| | - Jerry Hsu
- Department of Cell and Developmental Biology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
| | - Fabio A. Echeverry
- Dominick P. Purpura Department of Neuroscience, Albert Einstein College of Medicine, Bronx, New York, United States of America
| | - Roshan A. Jain
- Department of Cell and Developmental Biology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
| | - Marc A. Wolman
- Department of Cell and Developmental Biology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
| | - Alberto E. Pereda
- Dominick P. Purpura Department of Neuroscience, Albert Einstein College of Medicine, Bronx, New York, United States of America
| | - Michael Granato
- Department of Cell and Developmental Biology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
- * E-mail:
| |
Collapse
|
6
|
Sadamitsu K, Shigemitsu L, Suzuki M, Ito D, Kashima M, Hirata H. Characterization of zebrafish GABA A receptor subunits. Sci Rep 2021; 11:6242. [PMID: 33737538 PMCID: PMC7973766 DOI: 10.1038/s41598-021-84646-3] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2020] [Accepted: 02/18/2021] [Indexed: 11/23/2022] Open
Abstract
γ-Aminobutyric acid (GABA), the major inhibitory neurotransmitter in the central nervous system, exerts its effect through the activation of GABA receptors. GABAA receptors are ligand-gated chloride channels composed of five subunit proteins. Mammals have 19 different GABAA receptor subunits (α1–6, β1–3, γ1–3, δ, ε, π, θ, and ρ1–3), the physiological properties of which have been assayed by electrophysiology. However, the evolutionary conservation of the physiological characteristics of diverged GABAA receptor subunits remains unclear. Zebrafish have 23 subunits (α1, α2a, α2b, α3–5, α6a, α6b, β1–4, γ1–3, δ, π, ζ, ρ1, ρ2a, ρ2b, ρ3a, and ρ3b), but the electrophysiological properties of these subunits have not been explored. In this study, we cloned the coding sequences for zebrafish GABAA receptor subunits and investigated their expression patterns in larval zebrafish by whole-mount in situ hybridization. We also performed electrophysiological recordings of GABA-evoked currents from Xenopus oocytes injected with one or multiple zebrafish GABAA receptor subunit cRNAs and calculated the half-maximal effective concentrations (EC50s) for each. Our results revealed the spatial expressions and electrophysiological GABA sensitivities of zebrafish GABAA receptors, suggesting that the properties of GABAA receptor subunits are conserved among vertebrates.
Collapse
Affiliation(s)
- Kenichiro Sadamitsu
- Department of Chemistry and Biological Science, College of Science and Engineering, Aoyama Gakuin University, Sagamihara, 252-5258, Japan
| | - Leona Shigemitsu
- Department of Chemistry and Biological Science, College of Science and Engineering, Aoyama Gakuin University, Sagamihara, 252-5258, Japan
| | - Marina Suzuki
- Department of Chemistry and Biological Science, College of Science and Engineering, Aoyama Gakuin University, Sagamihara, 252-5258, Japan
| | - Daishi Ito
- Department of Chemistry and Biological Science, College of Science and Engineering, Aoyama Gakuin University, Sagamihara, 252-5258, Japan
| | - Makoto Kashima
- Department of Chemistry and Biological Science, College of Science and Engineering, Aoyama Gakuin University, Sagamihara, 252-5258, Japan
| | - Hiromi Hirata
- Department of Chemistry and Biological Science, College of Science and Engineering, Aoyama Gakuin University, Sagamihara, 252-5258, Japan.
| |
Collapse
|
7
|
Gomila AMJ, Rustler K, Maleeva G, Nin-Hill A, Wutz D, Bautista-Barrufet A, Rovira X, Bosch M, Mukhametova E, Petukhova E, Ponomareva D, Mukhamedyarov M, Peiretti F, Alfonso-Prieto M, Rovira C, König B, Bregestovski P, Gorostiza P. Photocontrol of Endogenous Glycine Receptors In Vivo. Cell Chem Biol 2020; 27:1425-1433.e7. [PMID: 32846115 DOI: 10.1016/j.chembiol.2020.08.005] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2019] [Revised: 04/14/2020] [Accepted: 08/04/2020] [Indexed: 12/15/2022]
Abstract
Glycine receptors (GlyRs) are indispensable for maintaining excitatory/inhibitory balance in neuronal circuits that control reflexes and rhythmic motor behaviors. Here we have developed Glyght, a GlyR ligand controlled with light. It is selective over other Cys-loop receptors, is active in vivo, and displays an allosteric mechanism of action. The photomanipulation of glycinergic neurotransmission opens new avenues to understanding inhibitory circuits in intact animals and to developing drug-based phototherapies.
Collapse
Affiliation(s)
- Alexandre M J Gomila
- Institute for Bioengineering of Catalonia (IBEC), The Barcelona Institute of Science and Technology (BIST), Barcelona 08028, Spain
| | - Karin Rustler
- University of Regensburg, Institute of Organic Chemistry, Regensburg 93053, Germany
| | - Galyna Maleeva
- Institute for Bioengineering of Catalonia (IBEC), The Barcelona Institute of Science and Technology (BIST), Barcelona 08028, Spain; Aix-Marseille Université, INSERM, INS, Institut de Neurosciences des Systèmes, Marseille 13005, France
| | - Alba Nin-Hill
- University of Barcelona, Department of Inorganic and Organic Chemistry, Institute of Theoretical Chemistry (IQTCUB), Barcelona 08028, Spain
| | - Daniel Wutz
- University of Regensburg, Institute of Organic Chemistry, Regensburg 93053, Germany
| | - Antoni Bautista-Barrufet
- Institute for Bioengineering of Catalonia (IBEC), The Barcelona Institute of Science and Technology (BIST), Barcelona 08028, Spain
| | - Xavier Rovira
- Institute for Bioengineering of Catalonia (IBEC), The Barcelona Institute of Science and Technology (BIST), Barcelona 08028, Spain
| | - Miquel Bosch
- Institute for Bioengineering of Catalonia (IBEC), The Barcelona Institute of Science and Technology (BIST), Barcelona 08028, Spain
| | - Elvira Mukhametova
- Aix-Marseille Université, INSERM, INS, Institut de Neurosciences des Systèmes, Marseille 13005, France; Kazan Federal University, Open Lab of Motor Neurorehabilitation, Kazan, Russia
| | - Elena Petukhova
- Institute of Neurosciences, Kazan State Medical University, Kazan, Russia
| | - Daria Ponomareva
- Institute of Neurosciences, Kazan State Medical University, Kazan, Russia
| | | | - Franck Peiretti
- Aix Marseille Université, INSERM 1263, INRA 1260, C2VN, Marseille, France
| | - Mercedes Alfonso-Prieto
- Institute for Advanced Simulation IAS-5 and Institute of Neuroscience and Medicine INM-9, Computational Biomedicine, Forschungszentrum Jülich, 52425 Jülich, Germany; Cécile and Oskar Vogt Institute for Brain Research, Medical Faculty, Heinrich Heine University Düsseldorf, 40225 Düsseldorf, Germany
| | - Carme Rovira
- University of Barcelona, Department of Inorganic and Organic Chemistry, Institute of Theoretical Chemistry (IQTCUB), Barcelona 08028, Spain; Catalan Institution for Research and Advanced Studies (ICREA), Barcelona 08003 Spain.
| | - Burkhard König
- University of Regensburg, Institute of Organic Chemistry, Regensburg 93053, Germany.
| | - Piotr Bregestovski
- Aix-Marseille Université, INSERM, INS, Institut de Neurosciences des Systèmes, Marseille 13005, France; Institute of Neurosciences, Kazan State Medical University, Kazan, Russia.
| | - Pau Gorostiza
- Institute for Bioengineering of Catalonia (IBEC), The Barcelona Institute of Science and Technology (BIST), Barcelona 08028, Spain; Catalan Institution for Research and Advanced Studies (ICREA), Barcelona 08003 Spain; CIBER-BBN, Madrid 28001 Spain.
| |
Collapse
|
8
|
Azman N, Zainudin NAIM, Ibrahim WNW. Fumonisin B 1 Production by Fusarium Species and Mycotoxigenic Effect on Larval Zebrafish. Trop Life Sci Res 2020; 31:91-107. [PMID: 33214858 PMCID: PMC7652242 DOI: 10.21315/tlsr2020.31.3.7] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Fumonisin B1 (FB1) is a common mycotoxin produced by Fusarium species particularly F. proliferatum and F. verticillioides. The toxin produced can cause adverse effects on humans and animals. The objectives of this study were to detect the production of FB1 based on the amplification of FUM1 gene, to quantify FB1 produced by the isolates using Ultra-fast Liquid Chromatography (UFLC) analysis, to examine the embryotoxicity effect of FB1 and to determine EC50 toward the larvae of zebrafish (Danio rerio). Fifty isolates of Fusarium species were isolated from different hosts throughout Malaysia. Successful amplification of the FUM1 gene showed the presence of this gene (800 bp) in the genome of 48 out of 50 isolates. The highest level of FB1 produced by F. proliferatum isolate B2433 was 6677.32 ppm meanwhile F. verticillioides isolate J1363 was 954.01 ppm. From the assessment of embryotoxicity test of FB1 on larvae of zebrafish, five concentrations of FB1 (0.43 ppm, 0.58 ppm, 0.72 ppm, 0.87 ppm and 1.00 ppm) were tested. Morphological changes of the FB1 exposed-larvae were observed at 24 to 168 hpf. The mortality rate and abnormality of zebrafish larvae were significantly increased at 144 hpf exposure. Meanwhile, the spontaneous tail coiling showed a significant difference. There were no significant differences in the heartbeat rate. As a conclusion, the presence of FUM1 in every isolate can be detected by FUM1 gene analysis and both of the species produced different concentrations of FB1. This is the first report of FB1 produced by Fusarium species gave a significant effect on zebrafish development.
Collapse
Affiliation(s)
- Najihah Azman
- Department of Biology, Faculty of Science, Universiti Putra Malaysia, 43400 Serdang, Selangor, Malaysia
| | | | | |
Collapse
|
9
|
Identification of the hypertension drug niflumic acid as a glycine receptor inhibitor. Sci Rep 2020; 10:13999. [PMID: 32814817 PMCID: PMC7438329 DOI: 10.1038/s41598-020-70983-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2020] [Accepted: 05/29/2020] [Indexed: 11/08/2022] Open
Abstract
Glycine is one of the major neurotransmitters in the brainstem and the spinal cord. Glycine binds to and activates glycine receptors (GlyRs), increasing Cl- conductance at postsynaptic sites. This glycinergic synaptic transmission contributes to the generation of respiratory rhythm and motor patterns. Strychnine inhibits GlyR by binding to glycine-binding site, while picrotoxin blocks GlyR by binding to the channel pore. We have previously reported that bath application of strychnine to zebrafish embryos causes bilateral muscle contractions in response to tactile stimulation. To explore the drug-mediated inhibition of GlyRs, we screened a chemical library of ~ 1,000 approved drugs and pharmacologically active molecules by observing touch-evoked response of zebrafish embryos in the presence of drugs. We found that exposure of zebrafish embryos to nifedipine (an inhibitor of voltage-gated calcium channel) or niflumic acid (an inhibitor of cyclooxygenase 2) caused bilateral muscle contractions just like strychnine-treated embryos showed. We then assayed strychnine, picrotoxin, nifedipine, and niflumic acid for concentration-dependent inhibition of glycine-mediated currents of GlyRs in oocytes and calculated IC50s. The results indicate that all of them concentration-dependently inhibit GlyR in the order of strychnine > picrotoxin > nifedipine > niflumic acid.
Collapse
|
10
|
RNA polymerase II subunit D is essential for zebrafish development. Sci Rep 2020; 10:13213. [PMID: 32764610 PMCID: PMC7413394 DOI: 10.1038/s41598-020-70110-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2020] [Accepted: 07/20/2020] [Indexed: 11/09/2022] Open
Abstract
DNA-directed RNA polymerase II (pol II) is composed of ten core and two dissociable subunits. The dissociable subcomplex is a heterodimer of Rpb4/Polr2d and Rpb7/Polr2g, which are encoded by RPB4/polr2d and RPB7/polr2g genes, respectively. Functional studies of Rpb4/Polr2d in yeast have revealed that Rpb4 plays a role primarily in pol II-mediated RNA synthesis and partly in various mRNA regulations including pre-mRNA splicing, nuclear export of mRNAs and decay of mRNAs. Although Rpb4 is evolutionally highly conserved from yeast to human, it is dispensable for survival in budding yeast S. cerevisiae, whereas it was indispensable for survival in fission yeast S. pombe, slime molds and fruit fly. To elucidate whether Rpb4/Polr2d is necessary for development and survival of vertebrate animals, we generated polr2d-deficient zebrafish. The polr2d mutant embryos exhibited progressive delay of somitogenesis at the onset of 11 h postfertilization (hpf). Mutant embryos then showed increased cell death at 15 hpf, displayed hypoplasia such as small eye and cardiac edema by 48 hpf and prematurely died by 60 hpf. In accordance with these developmental defects, our RT-qPCR revealed that expression of housekeeping and zygotic genes was diminished in mutants. Collectively, we conclude that Rpb4/Polr2d is indispensable for vertebrate development.
Collapse
|
11
|
Rauschenberger V, von Wardenburg N, Schaefer N, Ogino K, Hirata H, Lillesaar C, Kluck CJ, Meinck H, Borrmann M, Weishaupt A, Doppler K, Wickel J, Geis C, Sommer C, Villmann C. Glycine Receptor
Autoantibodies Impair Receptor Function and Induce Motor Dysfunction. Ann Neurol 2020; 88:544-561. [DOI: 10.1002/ana.25832] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2019] [Revised: 06/23/2020] [Accepted: 06/23/2020] [Indexed: 12/22/2022]
Affiliation(s)
- Vera Rauschenberger
- Institute for Clinical NeurobiologyUniversity Hospital, Julius Maximilian University of Würzburg Würzburg Germany
| | - Niels von Wardenburg
- Institute for Clinical NeurobiologyUniversity Hospital, Julius Maximilian University of Würzburg Würzburg Germany
| | - Natascha Schaefer
- Institute for Clinical NeurobiologyUniversity Hospital, Julius Maximilian University of Würzburg Würzburg Germany
| | - Kazutoyo Ogino
- Department of Chemistry and Biological ScienceCollege of Science and Engineering, Aoyama Gakuin University Tokyo Japan
| | - Hiromi Hirata
- Department of Chemistry and Biological ScienceCollege of Science and Engineering, Aoyama Gakuin University Tokyo Japan
| | - Christina Lillesaar
- Department of Child and Adolescent PsychiatryCenter of Mental Health, University Hospital of Würzburg Würzburg Germany
| | - Christoph J. Kluck
- Institute of Biochemistry, Emil Fischer Center, Friedrich Alexander University Erlangen–Nürnberg Erlangen Germany
| | | | - Marc Borrmann
- WittenHelios University Hospital Wuppertal, Department of Nephrology and Rheumatology, Witten/Herdecke University Germany
| | - Andreas Weishaupt
- Department of NeurologyUniversity Hospital Würzburg Würzburg Germany
| | - Kathrin Doppler
- Department of NeurologyUniversity Hospital Würzburg Würzburg Germany
| | - Jonathan Wickel
- Section of Translational Neuroimmunology, Department of NeurologyJena University Hospital Jena Germany
| | - Christian Geis
- Section of Translational Neuroimmunology, Department of NeurologyJena University Hospital Jena Germany
| | - Claudia Sommer
- Department of NeurologyUniversity Hospital Würzburg Würzburg Germany
| | - Carmen Villmann
- Institute for Clinical NeurobiologyUniversity Hospital, Julius Maximilian University of Würzburg Würzburg Germany
| |
Collapse
|
12
|
Zhao G, Wang Z, Xu L, Xia CX, Liu JX. Silver nanoparticles induce abnormal touch responses by damaging neural circuits in zebrafish embryos. CHEMOSPHERE 2019; 229:169-180. [PMID: 31078031 DOI: 10.1016/j.chemosphere.2019.04.223] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/03/2019] [Revised: 04/29/2019] [Accepted: 04/30/2019] [Indexed: 06/09/2023]
Abstract
Although silver nanoparticles (AgNPs) are used in various commercial products, the biological effects of AgNPs on fish embryogenesis and the underlying molecular mechanisms are still poorly understood. In this study, both touch responses and neuron membrane potential were found to be abnormal in AgNPs-stressed embryos. Moreover, neurogenesis genes were unveiled to be down-regulated and were enriched in ligand-gated ion channel activity, dopamine receptor signaling pathway, etc. in AgNPs-stressed embryos by microarray assays. Additionally, the down-regulated expression of otpa/sncgb - gad1b/gad2 dopaminergic neurotransmitter genes, robo2 - vim and glrbb synaptic transmission genes, and motor neuron genes isl1 &isl2a was further identified in both AgNPs- and Ag+-stressed embryos by qPCR, whole-mount in situ hybridization (WISH), and by using specific promoter-derived GFP fluorescence transgenic zebrafish. Moreover, the reduced expression of gad1b, gad2, and isl1 could be recovered by adding Ag+ chelating compound l-cysteine in AgNPs stressed embryos. Our results reveal for the first time that it is through damaging the formation of neural circuits, including dopaminergic neurotransmitter, synaptic transmission, and motor activities, that AgNPs induce abnormal electrical membrane properties, leading to dysfunctional touch responses and locomotor escape responses mostly via their released Ag+ during embryogenesis.
Collapse
Affiliation(s)
- Guang Zhao
- College of Fisheries, Key Laboratory of Freshwater Animal Breeding, Ministry of Agriculture, Huazhong Agricultural University, Wuhan, 430070, China
| | - ZiYang Wang
- College of Fisheries, Key Laboratory of Freshwater Animal Breeding, Ministry of Agriculture, Huazhong Agricultural University, Wuhan, 430070, China
| | - Lian Xu
- College of Fisheries, Key Laboratory of Freshwater Animal Breeding, Ministry of Agriculture, Huazhong Agricultural University, Wuhan, 430070, China
| | - Cheng-Xing Xia
- College of Fisheries, Key Laboratory of Freshwater Animal Breeding, Ministry of Agriculture, Huazhong Agricultural University, Wuhan, 430070, China.
| | - Jing-Xia Liu
- College of Fisheries, Key Laboratory of Freshwater Animal Breeding, Ministry of Agriculture, Huazhong Agricultural University, Wuhan, 430070, China.
| |
Collapse
|
13
|
Samarut E, Chalopin D, Riché R, Allard M, Liao M, Drapeau P. Individual knock out of glycine receptor alpha subunits identifies a specific requirement of glra1 for motor function in zebrafish. PLoS One 2019; 14:e0216159. [PMID: 31048868 PMCID: PMC6497278 DOI: 10.1371/journal.pone.0216159] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2018] [Accepted: 04/15/2019] [Indexed: 11/18/2022] Open
Abstract
Glycine receptors (GlyRs) are ligand-gated chloride channels mediating inhibitory neurotransmission in the brain stem and spinal cord. They function as pentamers composed of alpha and beta subunits for which 5 genes have been identified in human (GLRA1, GLRA2, GLRA3, GLRA4, GLRB). Several in vitro studies showed that the pentameric subtype composition as well as its stoichiometry influence the distribution and the molecular function of the receptor. Moreover, mutations in some of these genes are involved in different human conditions ranging from tinnitus to epilepsy and hyperekplexia, suggesting distinct functions of the different subunits. Although the beta subunit is essential for synaptic clustering of the receptor, the specific role of each alpha subtype is still puzzling in vivo. The zebrafish genome encodes for five glycine receptor alpha subunits (glra1, glra2, glra3, glra4a, glra4b) thus offering a model of choice to investigate the respective role of each subtype on general motor behaviour. After establishing a phylogeny of GlyR subunit evolution between human and zebrafish, we checked the temporal expression pattern of these transcripts during embryo development. Interestingly, we found that glra1 is the only maternally transmitted alpha subunit. We also showed that the expression of the different GlyR subunits starts at different time points during development. Lastly, in order to decipher the role of each alpha subunit on the general motor behaviour of the fish, we knocked out individually each alpha subunit by CRISPR/Cas9-targeted mutagenesis. Surprisingly, we found that knocking out any of the alpha2, 3, a4a or a4b subunit did not lead to any obvious developmental or motor phenotype. However, glra1-/- (hitch) embryos depicted a strong motor dysfunction from 3 days, making them incapable to swim and thus leading to their premature death. Our results infer a strong functional redundancy between alpha subunits and confirm the central role played by glra1 for proper inhibitory neurotransmission controlling locomotion. The genetic tools we developed here will be of general interest for further studies aiming at dissecting the role of GlyRs in glycinergic transmission in vivo and the hitch mutant (hic) is of specific relevance as a new model of hyperekplexia.
Collapse
Affiliation(s)
- Eric Samarut
- Research Center of the University of Montreal Hospital Center (CRCHUM), Department of Neurosciences, Université de Montréal, Montréal, QC, Canada
- DanioDesign Inc., Montréal, QC, Canada
- Modelis Inc., Montréal, QC, Canada
- * E-mail:
| | - Domitille Chalopin
- UnivLyon, ENS de Lyon, Université de Lyon, CNRS UMR5239, INSERM U1210, Lyon, France
| | - Raphaëlle Riché
- Research Center of the University of Montreal Hospital Center (CRCHUM), Department of Neurosciences, Université de Montréal, Montréal, QC, Canada
| | - Marc Allard
- Research Center of the University of Montreal Hospital Center (CRCHUM), Department of Neurosciences, Université de Montréal, Montréal, QC, Canada
| | - Meijiang Liao
- Research Center of the University of Montreal Hospital Center (CRCHUM), Department of Neurosciences, Université de Montréal, Montréal, QC, Canada
| | - Pierre Drapeau
- Research Center of the University of Montreal Hospital Center (CRCHUM), Department of Neurosciences, Université de Montréal, Montréal, QC, Canada
- DanioDesign Inc., Montréal, QC, Canada
| |
Collapse
|
14
|
Roberts AC, Chornak J, Alzagatiti JB, Ly DT, Bill BR, Trinkeller J, Pearce KC, Choe RC, Campbell CS, Wong D, Deutsch E, Hernandez S, Glanzman DL. Rapid habituation of a touch-induced escape response in Zebrafish (Danio rerio) Larvae. PLoS One 2019; 14:e0214374. [PMID: 30946762 PMCID: PMC6449028 DOI: 10.1371/journal.pone.0214374] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2018] [Accepted: 03/12/2019] [Indexed: 12/20/2022] Open
Abstract
Zebrafish larvae have several biological features that make them useful for cellular investigations of the mechanisms underlying learning and memory. Of particular interest in this regard is a rapid escape, or startle, reflex possessed by zebrafish larvae; this reflex, the C-start, is mediated by a relatively simple neuronal circuit and exhibits habituation, a non-associative form of learning. Here we demonstrate a rapid form of habituation of the C-start to touch that resembles the previously reported rapid habituation induced by auditory or vibrational stimuli. We also show that touch-induced habituation exhibits input specificity. This work sets the stage for in vivo optical investigations of the cellular sites of plasticity that mediate habituation of the C-start in the larval zebrafish.
Collapse
Affiliation(s)
- Adam C. Roberts
- Department of Psychology, California State University at Fullerton, Fullerton, CA, United States of America
| | - Julia Chornak
- Department of Neuroscience, University of California, Los Angeles, Los Angeles, CA, United States of America
| | - Joseph B. Alzagatiti
- Department of Integrative Biology and Physiology, University of California, Los Angeles, Los Angeles, CA, United States of America
| | - Duy T. Ly
- Department of Integrative Biology and Physiology, University of California, Los Angeles, Los Angeles, CA, United States of America
| | - Brent R. Bill
- Department of Biology, University of Texas at Tyler, Tyler, TX, United States of America
| | - Janie Trinkeller
- Department of Integrative Biology and Physiology, University of California, Los Angeles, Los Angeles, CA, United States of America
| | - Kaycey C. Pearce
- Department of Integrative Biology and Physiology, University of California, Los Angeles, Los Angeles, CA, United States of America
| | - Ronny C. Choe
- Department of Integrative Biology and Physiology, University of California, Los Angeles, Los Angeles, CA, United States of America
| | - C. S. Campbell
- Department of Psychology, California State University at Fullerton, Fullerton, CA, United States of America
| | - Dustin Wong
- Department of Integrative Biology and Physiology, University of California, Los Angeles, Los Angeles, CA, United States of America
| | - Emily Deutsch
- Department of Psychology, California State University at Fullerton, Fullerton, CA, United States of America
| | - Sarah Hernandez
- Department of Psychology, California State University at Fullerton, Fullerton, CA, United States of America
| | - David L. Glanzman
- Department of Integrative Biology and Physiology, University of California, Los Angeles, Los Angeles, CA, United States of America
- Department of Neurobiology, David Geffen School of Medicine at UCLA, Los Angeles, CA, United States of America
- Integrative Center for Learning and Memory, Brain Research Institute, David Geffen School of Medicine at UCLA, Los Angeles, CA, United States of America
- * E-mail:
| |
Collapse
|
15
|
A Modular Millifluidic Homeostatic Imaging Plate for Imaging of Larval Zebrafish. Zebrafish 2019; 16:37-46. [DOI: 10.1089/zeb.2018.1684] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
|
16
|
Low SE, Ito D, Hirata H. Characterization of the Zebrafish Glycine Receptor Family Reveals Insights Into Glycine Receptor Structure Function and Stoichiometry. Front Mol Neurosci 2018; 11:286. [PMID: 30323738 PMCID: PMC6130310 DOI: 10.3389/fnmol.2018.00286] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2018] [Accepted: 07/30/2018] [Indexed: 11/28/2022] Open
Abstract
To study characterization of zebrafish glycine receptors (zGlyRs), we assessed expression and function of five α- and two ß-subunit encoding GlyR in zebrafish. Our qPCR analysis revealed variable expression during development, while in situ hybridizations uncovered expression in the hindbrain and spinal cord; a finding consistent with the reported expression of GlyR subunits in these tissues from other organisms. Electrophysiological recordings using Xenopus oocytes revealed that all five α subunits form homomeric receptors activated by glycine, and inhibited by strychnine and picrotoxin. In contrast, ß subunits only formed functional heteromeric receptors when co-expressed with α subunits. Curiously, the second transmembranes of both ß subunits were found to lack a phenylalanine at the sixth position that is commonly associated with conferring picrotoxin resistance to heteromeric receptors. Consistent with the absence of phenylalanines at the sixth position, heteromeric zGlyRs often lacked significant picrotoxin resistance. Subsequent efforts revealed that resistance to picrotoxin in both zebrafish and human heteromeric GlyRs involves known residues within transmembrane 2, as well as previously unknown residues within transmembrane 3. We also found that a dominant mutation in human GlyRα1 that gives rise to hyperekplexia, and recessive mutations in zebrafish GlyRßb that underlie the bandoneon family of motor mutants, result in reduced receptor function. Lastly, through the use of a concatenated construct we demonstrate that zebrafish heteromeric receptors assemble with a stoichiometry of 3α:2ß. Collectively, our findings have furthered our knowledge regarding the assembly of heteromeric receptors, and the molecular basis of ß subunit-conferred picrotoxin resistance. These results should aid in future investigations of glycinergic signaling in zebrafish and mammals.
Collapse
Affiliation(s)
- Sean Eric Low
- Department of Chemistry and Biological Science, Aoyama Gakuin University, Sagamihara, Japan
| | - Daishi Ito
- Department of Chemistry and Biological Science, Aoyama Gakuin University, Sagamihara, Japan
| | - Hiromi Hirata
- Department of Chemistry and Biological Science, Aoyama Gakuin University, Sagamihara, Japan
| |
Collapse
|
17
|
Schaefer N, Zheng F, van Brederode J, Berger A, Leacock S, Hirata H, Paige CJ, Harvey RJ, Alzheimer C, Villmann C. Functional Consequences of the Postnatal Switch From Neonatal to Mutant Adult Glycine Receptor α1 Subunits in the Shaky Mouse Model of Startle Disease. Front Mol Neurosci 2018; 11:167. [PMID: 29910711 PMCID: PMC5992992 DOI: 10.3389/fnmol.2018.00167] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2018] [Accepted: 05/02/2018] [Indexed: 11/25/2022] Open
Abstract
Mutations in GlyR α1 or β subunit genes in humans and rodents lead to severe startle disease characterized by rigidity, massive stiffness and excessive startle responses upon unexpected tactile or acoustic stimuli. The recently characterized startle disease mouse mutant shaky carries a missense mutation (Q177K) in the β8-β9 loop within the large extracellular N-terminal domain of the GlyR α1 subunit. This results in a disrupted hydrogen bond network around K177 and faster GlyR decay times. Symptoms in mice start at postnatal day 14 and increase until premature death of homozygous shaky mice around 4–6 weeks after birth. Here we investigate the in vivo functional effects of the Q177K mutation using behavioral analysis coupled to protein biochemistry and functional assays. Western blot analysis revealed GlyR α1 subunit expression in wild-type and shaky animals around postnatal day 7, a week before symptoms in mutant mice become obvious. Before 2 weeks of age, homozygous shaky mice appeared healthy and showed no changes in body weight. However, analysis of gait and hind-limb clasping revealed that motor coordination was already impaired. Motor coordination and the activity pattern at P28 improved significantly upon diazepam treatment, a pharmacotherapy used in human startle disease. To investigate whether functional deficits in glycinergic neurotransmission are present prior to phenotypic onset, we performed whole-cell recordings from hypoglossal motoneurons (HMs) in brain stem slices from wild-type and shaky mice at different postnatal stages. Shaky homozygotes showed a decline in mIPSC amplitude and frequency at P9-P13, progressing to significant reductions in mIPSC amplitude and decay time at P18-24 compared to wild-type littermates. Extrasynaptic GlyRs recorded by bath-application of glycine also revealed reduced current amplitudes in shaky mice compared to wild-type neurons, suggesting that presynaptic GlyR function is also impaired. Thus, a distinct, but behaviorally ineffective impairment of glycinergic synapses precedes the symptoms onset in shaky mice. These findings extend our current knowledge on startle disease in the shaky mouse model in that they demonstrate how the progression of GlyR dysfunction causes, with a delay of about 1 week, the appearance of disease symptoms.
Collapse
Affiliation(s)
- Natascha Schaefer
- Institute for Clinical Neurobiology, Julius-Maximilians-University of Würzburg, Würzburg, Germany
| | - Fang Zheng
- Institute of Physiology and Pathophysiology, Friedrich-Alexander-University Erlangen-Nürnberg, Erlangen, Germany
| | - Johannes van Brederode
- Institute of Physiology and Pathophysiology, Friedrich-Alexander-University Erlangen-Nürnberg, Erlangen, Germany
| | - Alexandra Berger
- Princess Margaret Cancer Centre, University Health Network, University of Toronto, Toronto, ON, Canada
| | - Sophie Leacock
- Research Department of Pharmacology, UCL School of Pharmacy, London, United Kingdom
| | - Hiromi Hirata
- Department of Chemistry and Biological Science, College of Science and Engineering, Aoyama Gakuin University, Sagamihara, Japan
| | - Christopher J Paige
- Princess Margaret Cancer Centre, University Health Network, University of Toronto, Toronto, ON, Canada
| | - Robert J Harvey
- School of Health and Sport Sciences, University of the Sunshine Coast, Sippy Downs, QLD, Australia.,Sunshine Coast Health Institute, Birtinya, QLD, Australia
| | - Christian Alzheimer
- Institute of Physiology and Pathophysiology, Friedrich-Alexander-University Erlangen-Nürnberg, Erlangen, Germany
| | - Carmen Villmann
- Institute for Clinical Neurobiology, Julius-Maximilians-University of Würzburg, Würzburg, Germany
| |
Collapse
|
18
|
Leacock S, Syed P, James VM, Bode A, Kawakami K, Keramidas A, Suster M, Lynch JW, Harvey RJ. Structure/Function Studies of the α4 Subunit Reveal Evolutionary Loss of a GlyR Subtype Involved in Startle and Escape Responses. Front Mol Neurosci 2018; 11:23. [PMID: 29445326 PMCID: PMC5797729 DOI: 10.3389/fnmol.2018.00023] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2017] [Accepted: 01/16/2018] [Indexed: 01/08/2023] Open
Abstract
Inhibitory glycine receptors (GlyRs) are pentameric ligand-gated anion channels with major roles in startle disease/hyperekplexia (GlyR α1), cortical neuronal migration/autism spectrum disorder (GlyR α2), and inflammatory pain sensitization/rhythmic breathing (GlyR α3). However, the role of the GlyR α4 subunit has remained enigmatic, because the corresponding human gene (GLRA4) is thought to be a pseudogene due to an in-frame stop codon at position 390 within the fourth membrane-spanning domain (M4). Despite this, a recent genetic study has implicated GLRA4 in intellectual disability, behavioral problems and craniofacial anomalies. Analyzing data from sequenced genomes, we found that GlyR α4 subunit genes are predicted to be intact and functional in the majority of vertebrate species—with the exception of humans. Cloning of human GlyR α4 cDNAs excluded alternative splicing and RNA editing as mechanisms for restoring a full-length GlyR α4 subunit. Moreover, artificial restoration of the missing conserved arginine (R390) in the human cDNA was not sufficient to restore GlyR α4 function. Further bioinformatic and mutagenesis analysis revealed an additional damaging substitution at K59 that ablates human GlyR α4 function, which is not present in other vertebrate GlyR α4 sequences. The substitutions K59 and X390 were also present in the genome of an ancient Denisovan individual, indicating that GLRA4 has been a pseudogene for at least 30,000–50,000 years. In artificial synapses, we found that both mouse and gorilla α4β GlyRs mediate synaptic currents with unusually slow decay kinetics. Lastly, to gain insights into the biological role of GlyR α4 function, we studied the duplicated genes glra4a and glra4b in zebrafish. While glra4b expression is restricted to the retina, using a novel tol2-GAL4FF gene trap line (SAIGFF16B), we found that the zebrafish GlyR α4a subunit gene (glra4a) is strongly expressed in spinal cord and hindbrain commissural neurones. Using gene knockdown and a dominant-negative GlyR α4aR278Q mutant, we found that GlyR α4a contributes to touch-evoked escape behaviors in zebrafish. Thus, although GlyR α4 is unlikely to be involved in human startle responses or disease states, this subtype may contribute to escape behaviors in other organisms.
Collapse
Affiliation(s)
- Sophie Leacock
- Department of Pharmacology, UCL School of Pharmacy, London, United Kingdom
| | - Parnayan Syed
- Queensland Brain Institute, The University of Queensland, Brisbane, QLD, Australia
| | - Victoria M James
- Department of Pharmacology, UCL School of Pharmacy, London, United Kingdom
| | - Anna Bode
- Queensland Brain Institute, The University of Queensland, Brisbane, QLD, Australia
| | - Koichi Kawakami
- Division of Molecular and Developmental Biology, National Institute of Genetics and Department of Genetics, Graduate University for Advanced Studies (SOKENDAI), Mishima, Japan
| | - Angelo Keramidas
- Queensland Brain Institute, The University of Queensland, Brisbane, QLD, Australia
| | | | - Joseph W Lynch
- Queensland Brain Institute, The University of Queensland, Brisbane, QLD, Australia.,School of Biomedical Sciences, The University of Queensland, Brisbane, QLD, Australia
| | - Robert J Harvey
- School of Health and Sport Sciences, University of the Sunshine Coast, Sippy Downs, QLD, Australia.,Sunshine Coast Health Institute, Birtinya, QLD, Australia
| |
Collapse
|
19
|
Freifeld L, Odstrcil I, Förster D, Ramirez A, Gagnon JA, Randlett O, Costa EK, Asano S, Celiker OT, Gao R, Martin-Alarcon DA, Reginato P, Dick C, Chen L, Schoppik D, Engert F, Baier H, Boyden ES. Expansion microscopy of zebrafish for neuroscience and developmental biology studies. Proc Natl Acad Sci U S A 2017; 114:E10799-E10808. [PMID: 29162696 PMCID: PMC5740639 DOI: 10.1073/pnas.1706281114] [Citation(s) in RCA: 55] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
Expansion microscopy (ExM) allows scalable imaging of preserved 3D biological specimens with nanoscale resolution on fast diffraction-limited microscopes. Here, we explore the utility of ExM in the larval and embryonic zebrafish, an important model organism for the study of neuroscience and development. Regarding neuroscience, we found that ExM enabled the tracing of fine processes of radial glia, which are not resolvable with diffraction-limited microscopy. ExM further resolved putative synaptic connections, as well as molecular differences between densely packed synapses. Finally, ExM could resolve subsynaptic protein organization, such as ring-like structures composed of glycine receptors. Regarding development, we used ExM to characterize the shapes of nuclear invaginations and channels, and to visualize cytoskeletal proteins nearby. We detected nuclear invagination channels at late prophase and telophase, potentially suggesting roles for such channels in cell division. Thus, ExM of the larval and embryonic zebrafish may enable systematic studies of how molecular components are configured in multiple contexts of interest to neuroscience and developmental biology.
Collapse
Affiliation(s)
- Limor Freifeld
- Media Lab, Massachusetts Institute of Technology (MIT), Cambridge, MA 02139
| | - Iris Odstrcil
- Department of Molecular and Cellular Biology, Harvard University, Cambridge, MA 02138
| | - Dominique Förster
- Department Genes-Circuits-Behavior, Max Planck Institute of Neurobiology, Martinsried 82152, Germany
| | - Alyson Ramirez
- Department of Molecular and Cellular Biology, Harvard University, Cambridge, MA 02138
| | - James A Gagnon
- Department of Molecular and Cellular Biology, Harvard University, Cambridge, MA 02138
| | - Owen Randlett
- Department of Molecular and Cellular Biology, Harvard University, Cambridge, MA 02138
| | - Emma K Costa
- Department of Brain and Cognitive Sciences, MIT, Cambridge, MA 02139
| | - Shoh Asano
- Media Lab, Massachusetts Institute of Technology (MIT), Cambridge, MA 02139
| | - Orhan T Celiker
- Department of Electrical Engineering and Computer Science, MIT, Cambridge, MA 02139
| | - Ruixuan Gao
- Media Lab, Massachusetts Institute of Technology (MIT), Cambridge, MA 02139
- McGovern Institute for Brain Research, MIT, Cambridge, MA 02139
| | | | - Paul Reginato
- Department of Biological Engineering, MIT, Cambridge, MA 02139
- Department of Genetics, Harvard Medical School, Cambridge, MA 02138
| | - Cortni Dick
- Media Lab, Massachusetts Institute of Technology (MIT), Cambridge, MA 02139
| | - Linlin Chen
- Media Lab, Massachusetts Institute of Technology (MIT), Cambridge, MA 02139
- Neuroscience Program, Wellesley College, Wellesley, MA 02481
| | - David Schoppik
- Department of Otolaryngology, New York University School of Medicine, New York, NY 10016
- Department of Neuroscience and Physiology, New York University School of Medicine, New York, NY 10016
- Neuroscience Institute, New York University School of Medicine, New York NY 10016
| | - Florian Engert
- Department of Molecular and Cellular Biology, Harvard University, Cambridge, MA 02138
| | - Herwig Baier
- Department Genes-Circuits-Behavior, Max Planck Institute of Neurobiology, Martinsried 82152, Germany
| | - Edward S Boyden
- Media Lab, Massachusetts Institute of Technology (MIT), Cambridge, MA 02139;
- Department of Brain and Cognitive Sciences, MIT, Cambridge, MA 02139
- Department of Electrical Engineering and Computer Science, MIT, Cambridge, MA 02139
- McGovern Institute for Brain Research, MIT, Cambridge, MA 02139
- Center for Neurobiological Engineering, MIT, Cambridge, MA 02139
| |
Collapse
|
20
|
Congenital myopathy results from misregulation of a muscle Ca2+ channel by mutant Stac3. Proc Natl Acad Sci U S A 2016; 114:E228-E236. [PMID: 28003463 DOI: 10.1073/pnas.1619238114] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Skeletal muscle contractions are initiated by an increase in Ca2+ released during excitation-contraction (EC) coupling, and defects in EC coupling are associated with human myopathies. EC coupling requires communication between voltage-sensing dihydropyridine receptors (DHPRs) in transverse tubule membrane and Ca2+ release channel ryanodine receptor 1 (RyR1) in the sarcoplasmic reticulum (SR). Stac3 protein (SH3 and cysteine-rich domain 3) is an essential component of the EC coupling apparatus and a mutation in human STAC3 causes the debilitating Native American myopathy (NAM), but the nature of how Stac3 acts on the DHPR and/or RyR1 is unknown. Using electron microscopy, electrophysiology, and dynamic imaging of zebrafish muscle fibers, we find significantly reduced DHPR levels, functionality, and stability in stac3 mutants. Furthermore, stac3NAM myofibers exhibited increased caffeine-induced Ca2+ release across a wide range of concentrations in the absence of altered caffeine sensitivity as well as increased Ca2+ in internal stores, which is consistent with increased SR luminal Ca2+ These findings define critical roles for Stac3 in EC coupling and human disease.
Collapse
|
21
|
Ogino K, Hirata H. Defects of the Glycinergic Synapse in Zebrafish. Front Mol Neurosci 2016; 9:50. [PMID: 27445686 PMCID: PMC4925712 DOI: 10.3389/fnmol.2016.00050] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2016] [Accepted: 06/13/2016] [Indexed: 12/26/2022] Open
Abstract
Glycine mediates fast inhibitory synaptic transmission. Physiological importance of the glycinergic synapse is well established in the brainstem and the spinal cord. In humans, the loss of glycinergic function in the spinal cord and brainstem leads to hyperekplexia, which is characterized by an excess startle reflex to sudden acoustic or tactile stimulation. In addition, glycinergic synapses in this region are also involved in the regulation of respiration and locomotion, and in the nociceptive processing. The importance of the glycinergic synapse is conserved across vertebrate species. A teleost fish, the zebrafish, offers several advantages as a vertebrate model for research of glycinergic synapse. Mutagenesis screens in zebrafish have isolated two motor defective mutants that have pathogenic mutations in glycinergic synaptic transmission: bandoneon (beo) and shocked (sho). Beo mutants have a loss-of-function mutation of glycine receptor (GlyR) β-subunit b, alternatively, sho mutant is a glycinergic transporter 1 (GlyT1) defective mutant. These mutants are useful animal models for understanding of glycinergic synaptic transmission and for identification of novel therapeutic agents for human diseases arising from defect in glycinergic transmission, such as hyperekplexia or glycine encephalopathy. Recent advances in techniques for genome editing and for imaging and manipulating of a molecule or a physiological process make zebrafish more attractive model. In this review, we describe the glycinergic defective zebrafish mutants and the technical advances in both forward and reverse genetic approaches as well as in vivo visualization and manipulation approaches for the study of the glycinergic synapse in zebrafish.
Collapse
Affiliation(s)
- Kazutoyo Ogino
- Department of Chemistry and Biological Science, College of Science and Engineering, Aoyama Gakuin University Sagamihara, Japan
| | - Hiromi Hirata
- Department of Chemistry and Biological Science, College of Science and Engineering, Aoyama Gakuin University Sagamihara, Japan
| |
Collapse
|
22
|
Umeda K, Ishizuka T, Yawo H, Shoji W. Position- and quantity-dependent responses in zebrafish turning behavior. Sci Rep 2016; 6:27888. [PMID: 27292818 PMCID: PMC4904276 DOI: 10.1038/srep27888] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2016] [Accepted: 05/27/2016] [Indexed: 11/30/2022] Open
Abstract
Neural reflexes are stereotypical automatic responses often modulated by both intrinsic and environmental factors. We report herein that zebrafish larval C-shaped turning is modulated by the stimulated position of Rohon-Beard (RB) neurons. Targeted stimulation of more anterior RB neurons produces larger trunk flexion, which anticipates adult escape behavior by coordinated turning toward the appropriate direction. We also demonstrated that turning laterality varies with the numbers of stimulated neurons. Multi-cell stimulation of RB neurons elicits contralateral turning, as seen in the touch response to physical contact, while minimum input from single-cell stimulation induces ipsilateral turning, a phenomenon not previously reported. This ipsilateral response, but not the contralateral one, is impaired by transecting the ascending neural tract known as the dorsolateral fascicule (DLF), indicating that two, distinct neural circuits trigger these two responses. Our results suggest that RB neurons transmit the position and quantity of sensory information, which are then processed separately to modulate behavioral strength and to select turning laterality.
Collapse
Affiliation(s)
- Keiko Umeda
- Frontier Research Institute for Interdisciplinary Sciences, Tohoku University, Sendai, 9808578, Japan
| | - Toru Ishizuka
- Department of Developmental Biology &Neuroscience, Tohoku University Graduate School of Life Sciences, Sendai, 9808577, Japan
| | - Hiromu Yawo
- Department of Developmental Biology &Neuroscience, Tohoku University Graduate School of Life Sciences, Sendai, 9808577, Japan
| | - Wataru Shoji
- Frontier Research Institute for Interdisciplinary Sciences, Tohoku University, Sendai, 9808578, Japan.,Department of Project Programs, Institute of Development, Aging and Cancer, Tohoku University, Sendai, 9808575, Japan
| |
Collapse
|
23
|
An E3-ligase-based method for ablating inhibitory synapses. Nat Methods 2016; 13:673-8. [PMID: 27271196 PMCID: PMC5312699 DOI: 10.1038/nmeth.3894] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2015] [Accepted: 05/09/2016] [Indexed: 01/08/2023]
Abstract
Although neuronal activity can be modulated using a variety of techniques, there are currently few methods for controlling neuronal connectivity. We introduce a tool (GFE3) that mediates the fast, specific and reversible elimination of inhibitory synaptic inputs onto genetically determined neurons. GFE3 is a fusion between an E3 ligase, which mediates the ubiquitination and rapid degradation of proteins, and a recombinant, antibody-like protein (FingR) that binds to gephyrin. Expression of GFE3 leads to a strong and specific reduction of gephyrin in culture or in vivo and to a substantial decrease in phasic inhibition onto cells that express GFE3. By temporarily expressing GFE3 we showed that inhibitory synapses regrow following ablation. Thus, we have created a simple, reversible method for modulating inhibitory synaptic input onto genetically determined cells.
Collapse
|
24
|
Burghardt TP, Ajtai K, Sun X, Takubo N, Wang Y. In vivo myosin step-size from zebrafish skeletal muscle. Open Biol 2016; 6:rsob.160075. [PMID: 27249818 PMCID: PMC4892436 DOI: 10.1098/rsob.160075] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2016] [Accepted: 05/03/2016] [Indexed: 11/20/2022] Open
Abstract
Muscle myosins transduce ATP free energy into actin displacement to power contraction. In vivo, myosin side chains are modified post-translationally under native conditions, potentially impacting function. Single myosin detection provides the ‘bottom-up’ myosin characterization probing basic mechanisms without ambiguities inherent to ensemble observation. Macroscopic muscle physiological experimentation provides the definitive ‘top-down’ phenotype characterizations that are the concerns in translational medicine. In vivo single myosin detection in muscle from zebrafish embryo models for human muscle fulfils ambitions for both bottom-up and top-down experimentation. A photoactivatable green fluorescent protein (GFP)-tagged myosin light chain expressed in transgenic zebrafish skeletal muscle specifically modifies the myosin lever-arm. Strychnine induces the simultaneous contraction of the bilateral tail muscles in a live embryo, causing them to be isometric while active. Highly inclined thin illumination excites the GFP tag of single lever-arms and its super-resolution orientation is measured from an active isometric muscle over a time sequence covering many transduction cycles. Consecutive frame lever-arm angular displacement converts to step-size by its product with the estimated lever-arm length. About 17% of the active myosin steps that fall between 2 and 7 nm are implicated as powerstrokes because they are beyond displacements detected from either relaxed or ATP-depleted (rigor) muscle.
Collapse
Affiliation(s)
- Thomas P Burghardt
- Department of Biochemistry and Molecular Biology, Mayo Clinic Rochester, Rochester, MN 55905, USA Department of Physiology and Biomedical Engineering, Mayo Clinic Rochester, Rochester, MN 55905, USA
| | - Katalin Ajtai
- Department of Biochemistry and Molecular Biology, Mayo Clinic Rochester, Rochester, MN 55905, USA
| | - Xiaojing Sun
- Department of Biochemistry and Molecular Biology, Mayo Clinic Rochester, Rochester, MN 55905, USA
| | - Naoko Takubo
- Department of Biochemistry and Molecular Biology, Mayo Clinic Rochester, Rochester, MN 55905, USA
| | - Yihua Wang
- Department of Biochemistry and Molecular Biology, Mayo Clinic Rochester, Rochester, MN 55905, USA
| |
Collapse
|
25
|
Cunliffe VT. Building a zebrafish toolkit for investigating the pathobiology of epilepsy and identifying new treatments for epileptic seizures. J Neurosci Methods 2016. [DOI: 10.1016/j.jneumeth.2015.07.015] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
|
26
|
Burghardt TP, Sun X, Wang Y, Ajtai K. In vitro and in vivo single myosin step-sizes in striated muscle. J Muscle Res Cell Motil 2015; 36:463-77. [PMID: 26728749 PMCID: PMC4764389 DOI: 10.1007/s10974-015-9440-2] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2015] [Accepted: 12/11/2015] [Indexed: 10/22/2022]
Abstract
Myosin in muscle transduces ATP free energy into the mechanical work of moving actin. It has a motor domain transducer containing ATP and actin binding sites, and, mechanical elements coupling motor impulse to the myosin filament backbone providing transduction/mechanical-coupling. The mechanical coupler is a lever-arm stabilized by bound essential and regulatory light chains. The lever-arm rotates cyclically to impel bound filamentous actin. Linear actin displacement due to lever-arm rotation is the myosin step-size. A high-throughput quantum dot labeled actin in vitro motility assay (Qdot assay) measures motor step-size in the context of an ensemble of actomyosin interactions. The ensemble context imposes a constant velocity constraint for myosins interacting with one actin filament. In a cardiac myosin producing multiple step-sizes, a "second characterization" is step-frequency that adjusts longer step-size to lower frequency maintaining a linear actin velocity identical to that from a shorter step-size and higher frequency actomyosin cycle. The step-frequency characteristic involves and integrates myosin enzyme kinetics, mechanical strain, and other ensemble affected characteristics. The high-throughput Qdot assay suits a new paradigm calling for wide surveillance of the vast number of disease or aging relevant myosin isoforms that contrasts with the alternative model calling for exhaustive research on a tiny subset myosin forms. The zebrafish embryo assay (Z assay) performs single myosin step-size and step-frequency assaying in vivo combining single myosin mechanical and whole muscle physiological characterizations in one model organism. The Qdot and Z assays cover "bottom-up" and "top-down" assaying of myosin characteristics.
Collapse
Affiliation(s)
- Thomas P Burghardt
- Department of Biochemistry and Molecular Biology, Mayo Clinic Rochester, Rochester, MN, 55905, USA.
- Department of Physiology and Biomedical Engineering, Mayo Clinic Rochester, Rochester, MN, 55905, USA.
| | - Xiaojing Sun
- Department of Biochemistry and Molecular Biology, Mayo Clinic Rochester, Rochester, MN, 55905, USA
| | - Yihua Wang
- Department of Biochemistry and Molecular Biology, Mayo Clinic Rochester, Rochester, MN, 55905, USA
| | - Katalin Ajtai
- Department of Biochemistry and Molecular Biology, Mayo Clinic Rochester, Rochester, MN, 55905, USA
| |
Collapse
|
27
|
Capo-Chichi JM, Boissel S, Brustein E, Pickles S, Fallet-Bianco C, Nassif C, Patry L, Dobrzeniecka S, Liao M, Labuda D, Samuels ME, Hamdan FF, Velde CV, Rouleau GA, Drapeau P, Michaud JL. Disruption ofCLPBis associated with congenital microcephaly, severe encephalopathy and 3-methylglutaconic aciduria. J Med Genet 2015; 52:303-11. [DOI: 10.1136/jmedgenet-2014-102952] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2014] [Accepted: 01/12/2015] [Indexed: 11/04/2022]
|
28
|
Monesson-Olson BD, Troconis EL, Trapani JG. Recording field potentials from zebrafish larvae during escape responses. JOURNAL OF UNDERGRADUATE NEUROSCIENCE EDUCATION : JUNE : A PUBLICATION OF FUN, FACULTY FOR UNDERGRADUATE NEUROSCIENCE 2014; 13:A52-A58. [PMID: 25565920 PMCID: PMC4281049] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 07/10/2014] [Revised: 09/26/2014] [Accepted: 09/30/2014] [Indexed: 06/04/2023]
Abstract
Among vertebrates, startle responses are a ubiquitous method for alerting, and avoiding or escaping from alarming or dangerous stimuli. In zebrafish larvae, fast escape behavior is easily evoked through either acoustic or tactile stimuli. For example, a light touch to the head will excite trigeminal neurons that in turn excite a large reticulospinal neuron in the hindbrain called the Mauthner cell (M-cell). The M-cell action potential then travels down the contralateral trunk of the larva exciting motoneurons, which subsequently excite the entire axial musculature, producing a large amplitude body bend away from the source of the stimulus. This body conformation is known as the "C-bend" due to the shape of the larva during the behavior. As a result of the semi-synchronized activation of the M-cell, the population of motor neurons, and the axial trunk muscles, a large field potential is generated and can be recorded from free-swimming or fixed-position larvae. Undergraduate laboratories that record field potentials during escape responses in larval zebrafish are relatively simple to setup and allow students to observe and study the escape reflex circuit. Furthermore, by testing hypotheses, analyzing data and writing journal-style laboratory reports, students have multiple opportunities to learn about many neuroscience topics including vertebrate reflexes; sensory transduction; synaptic-, neuro-, and muscle-physiology; the M-cell mediated escape response; and the zebrafish as a model organism. Here, we detail the equipment, software, and recording setup necessary to observe field potentials in an undergraduate teaching lab. Additionally, we discuss potential advanced laboratory exercises and pedagogical outcomes. Finally, we note possible low-cost alternatives for recording field potentials.
Collapse
Affiliation(s)
| | | | - Josef G. Trapani
- Address correspondence to: Dr. Josef G. Trapani, Biology Department, Amherst College, Amherst, MA 01002.
| |
Collapse
|
29
|
Wiggin TD, Peck JH, Masino MA. Coordination of fictive motor activity in the larval zebrafish is generated by non-segmental mechanisms. PLoS One 2014; 9:e109117. [PMID: 25275377 PMCID: PMC4183566 DOI: 10.1371/journal.pone.0109117] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2014] [Accepted: 08/25/2014] [Indexed: 01/15/2023] Open
Abstract
The cellular and network basis for most vertebrate locomotor central pattern generators (CPGs) is incompletely characterized, but organizational models based on known CPG architectures have been proposed. Segmental models propose that each spinal segment contains a circuit that controls local coordination and sends longer projections to coordinate activity between segments. Unsegmented/continuous models propose that patterned motor output is driven by gradients of neurons and synapses that do not have segmental boundaries. We tested these ideas in the larval zebrafish, an animal that swims in discrete episodes, each of which is composed of coordinated motor bursts that progress rostrocaudally and alternate from side to side. We perturbed the spinal cord using spinal transections or strychnine application and measured the effect on fictive motor output. Spinal transections eliminated episode structure, and reduced both rostrocaudal and side-to-side coordination. Preparations with fewer intact segments were more severely affected, and preparations consisting of midbody and caudal segments were more severely affected than those consisting of rostral segments. In reduced preparations with the same number of intact spinal segments, side-to-side coordination was more severely disrupted than rostrocaudal coordination. Reducing glycine receptor signaling with strychnine reversibly disrupted both rostrocaudal and side-to-side coordination in spinalized larvae without disrupting episodic structure. Both spinal transection and strychnine decreased the stability of the motor rhythm, but this effect was not causal in reducing coordination. These results are inconsistent with a segmented model of the spinal cord and are better explained by a continuous model in which motor neuron coordination is controlled by segment-spanning microcircuits.
Collapse
Affiliation(s)
- Timothy D. Wiggin
- Graduate Program in Neuroscience, University of Minnesota, Minneapolis, Minnesota, United States of America
| | - Jack H. Peck
- Department of Neuroscience, University of Minnesota, Minneapolis, Minnesota, United States of America
| | - Mark A. Masino
- Graduate Program in Neuroscience, University of Minnesota, Minneapolis, Minnesota, United States of America
- Department of Neuroscience, University of Minnesota, Minneapolis, Minnesota, United States of America
- * E-mail:
| |
Collapse
|
30
|
Medan V, Preuss T. The Mauthner-cell circuit of fish as a model system for startle plasticity. ACTA ACUST UNITED AC 2014; 108:129-40. [PMID: 25106811 DOI: 10.1016/j.jphysparis.2014.07.006] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2014] [Revised: 07/18/2014] [Accepted: 07/21/2014] [Indexed: 11/30/2022]
Abstract
The Mauthner-cell (M-cell) system of teleost fish has a long history as an experimental model for addressing a wide range of neurobiological questions. Principles derived from studies on this system have contributed significantly to our understanding at multiple levels, from mechanisms of synaptic transmission and synaptic plasticity to the concepts of a decision neuron that initiates key aspects of the startle behavior. Here we will review recent work that focuses on the neurophysiological and neuropharmacological basis for modifications in the M-cell circuit. After summarizing the main excitatory and inhibitory inputs to the M-cell, we review experiments showing startle response modulation by temperature, social status, and sensory filtering. Although very different in nature, actions of these three sources of modulation converge in the M-cell network. Mechanisms of modulation include altering the excitability of the M-cell itself as well as changes in excitatory and inhibitor drive, highlighting the role of balanced excitation and inhibition for escape decisions. One of the most extensively studied forms of startle plasticity in vertebrates is prepulse inhibition (PPI), a sensorimotor gating phenomenon, which is impaired in several information processing disorders. Finally, we review recent work in the M-cell system which focuses on the cellular mechanisms of PPI and its modulation by serotonin and dopamine.
Collapse
Affiliation(s)
- Violeta Medan
- Dept. de Fisiología y Biología Molecular y Celular, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Intendente Guiraldes 2160, Buenos Aires 1428, Argentina; Instituto de Fisiología, Biología Molecular y Neurociencias, CONICET, Argentina.
| | - Thomas Preuss
- Psychology Dept. Hunter College, City University of New York, 695 Park Ave., New York, NY 10065, USA.
| |
Collapse
|
31
|
Zannino DA, Downes GB, Sagerström CG. prdm12b specifies the p1 progenitor domain and reveals a role for V1 interneurons in swim movements. Dev Biol 2014. [PMID: 24631215 DOI: 10.1016/j.vdbio.2014.02.025] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
Proper functioning of the vertebrate central nervous system requires the precise positioning of many neuronal cell types. This positioning is established during early embryogenesis when gene regulatory networks pattern the neural tube along its anteroposterior and dorsoventral axes. Dorsoventral patterning of the embryonic neural tube gives rise to multiple progenitor cell domains that go on to differentiate unique classes of neurons and glia. While the genetic program is reasonably well understood for some lineages, such as ventrally derived motor neurons and glia, other lineages are much less characterized. Here we show that prdm12b, a member of the PR domain containing-family of transcriptional regulators, is expressed in the p1 progenitor domain of the zebrafish neural tube in response to Sonic Hedgehog signaling. We find that disruption of prdm12b function leads to dorsal expansion of nkx6.1 expression and loss of p1-derived eng1b-expressing V1 interneurons, while the adjacent p0 and p2 domains are unaffected. We also demonstrate that prdm12b-deficient fish exhibit an abnormal touch-evoked escape response with excessive body contractions and a prolonged response time, as well as an inability to coordinate swimming movements, thereby revealing a functional role for V1 interneurons in locomotor circuits. We conclude that prdm12b is required for V1 interneuron specification and that these neurons control swimming movements in zebrafish.
Collapse
Affiliation(s)
- Denise A Zannino
- Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, 364 Plantation St./LRB815, Worcester, MA 01605-2324, USA
| | - Gerald B Downes
- Department of Biology, University of Massachusetts, Amherst, MA 01003, USA
| | - Charles G Sagerström
- Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, 364 Plantation St./LRB815, Worcester, MA 01605-2324, USA.
| |
Collapse
|
32
|
Mirror movement-like defects in startle behavior of zebrafish dcc mutants are caused by aberrant midline guidance of identified descending hindbrain neurons. J Neurosci 2014; 34:2898-909. [PMID: 24553931 DOI: 10.1523/jneurosci.2420-13.2014] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Mirror movements are involuntary movements on one side of the body that occur simultaneously with intentional movements on the contralateral side. Humans with heterozygous mutations in the axon guidance receptor DCC display such mirror movements, where unilateral stimulation results in inappropriate bilateral motor output. Currently, it is unclear whether mirror movements are caused by incomplete midline crossing and reduced commissural connectivity of DCC-dependent descending pathways or by aberrant ectopic ipsilateral axonal projections of normally commissural neurons. Here, we show that in response to unilateral tactile stimuli, zebrafish dcc mutant larvae perform involuntary turns on the inappropriate body side. We show that these mirror movement-like deficits are associated with axonal guidance defects of two identified groups of commissural reticulospinal hindbrain neurons. Moreover, we demonstrate that in dcc mutants, axons of these identified neurons frequently fail to cross the midline and instead project ipsilaterally. Whereas laser ablation of these neurons in wild-type animals does not affect turning movements, their ablation in dcc mutants restores turning movements. Thus, our results demonstrate that in dcc mutants, turns on the inappropriate side of the body are caused by aberrant ipsilateral axonal projections, and suggest that aberrant ipsilateral connectivity of a very small number of descending axons is sufficient to induce incorrect movement patterns.
Collapse
|
33
|
Zannino DA, Downes GB, Sagerström CG. prdm12b specifies the p1 progenitor domain and reveals a role for V1 interneurons in swim movements. Dev Biol 2014; 390:247-60. [PMID: 24631215 DOI: 10.1016/j.ydbio.2014.02.025] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2013] [Revised: 02/12/2014] [Accepted: 02/28/2014] [Indexed: 01/23/2023]
Abstract
Proper functioning of the vertebrate central nervous system requires the precise positioning of many neuronal cell types. This positioning is established during early embryogenesis when gene regulatory networks pattern the neural tube along its anteroposterior and dorsoventral axes. Dorsoventral patterning of the embryonic neural tube gives rise to multiple progenitor cell domains that go on to differentiate unique classes of neurons and glia. While the genetic program is reasonably well understood for some lineages, such as ventrally derived motor neurons and glia, other lineages are much less characterized. Here we show that prdm12b, a member of the PR domain containing-family of transcriptional regulators, is expressed in the p1 progenitor domain of the zebrafish neural tube in response to Sonic Hedgehog signaling. We find that disruption of prdm12b function leads to dorsal expansion of nkx6.1 expression and loss of p1-derived eng1b-expressing V1 interneurons, while the adjacent p0 and p2 domains are unaffected. We also demonstrate that prdm12b-deficient fish exhibit an abnormal touch-evoked escape response with excessive body contractions and a prolonged response time, as well as an inability to coordinate swimming movements, thereby revealing a functional role for V1 interneurons in locomotor circuits. We conclude that prdm12b is required for V1 interneuron specification and that these neurons control swimming movements in zebrafish.
Collapse
Affiliation(s)
- Denise A Zannino
- Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, 364 Plantation St./LRB815, Worcester, MA 01605-2324, USA
| | - Gerald B Downes
- Department of Biology, University of Massachusetts, Amherst, MA 01003, USA
| | - Charles G Sagerström
- Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, 364 Plantation St./LRB815, Worcester, MA 01605-2324, USA.
| |
Collapse
|
34
|
Bailey J, Oliveri A, Levin ED. Zebrafish model systems for developmental neurobehavioral toxicology. ACTA ACUST UNITED AC 2014; 99:14-23. [PMID: 23723169 DOI: 10.1002/bdrc.21027] [Citation(s) in RCA: 122] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2013] [Accepted: 03/06/2013] [Indexed: 02/05/2023]
Abstract
Zebrafish offer many advantages that complement classic mammalian models for the study of normal development as well as for the teratogenic effects of exposure to hazardous compounds. The clear chorion and embryo of the zebrafish allow for continuous visualization of the anatomical changes associated with development, which, along with short maturation times and the capability of complex behavior, makes this model particularly useful for measuring changes to the developing nervous system. Moreover, the rich array of developmental, behavioral, and molecular benefits offered by the zebrafish have contributed to an increasing demand for the use of zebrafish in behavioral teratology. Essential for this endeavor has been the development of a battery of tests to evaluate a spectrum of behavior in zebrafish. Measures of sensorimotor plasticity, emotional function, cognition and social interaction have been used to characterize the persisting adverse effects of developmental exposure to a variety of chemicals including therapeutic drugs, drugs of abuse and environmental toxicants. In this review, we present and discuss such tests and data from a range of developmental neurobehavioral toxicology studies using zebrafish as a model. Zebrafish provide a key intermediate model between high throughput in vitro screens and the classic mammalian models as they have the accessibility of in vitro models and the complex functional capabilities of mammalian models.
Collapse
Affiliation(s)
- Jordan Bailey
- Department of Psychiatry and Behavioral Sciences, Duke University Medical Center, Durham, North Carolina 27710, USA
| | | | | |
Collapse
|
35
|
Defective escape behavior in DEAH-box RNA helicase mutants improved by restoring glycine receptor expression. J Neurosci 2013; 33:14638-44. [PMID: 24027265 DOI: 10.1523/jneurosci.1157-13.2013] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
RNA helicases regulate RNA metabolism, but their substrate specificity and in vivo function remain largely unknown. We isolated spontaneous mutant zebrafish that exhibit an abnormal dorsal bend at the beginning of tactile-evoked escape swimming. Similar behavioral defects were observed in zebrafish embryos treated with strychnine, which blocks glycine receptors (GlyRs), suggesting that the abnormal motor response in mutants may be attributable to a deficit in glycinergic synaptic transmission. We identified a missense mutation in the gene encoding RNA helicase Dhx37. In Dhx37 mutants, ribosomal RNA levels were unchanged, whereas GlyR α1, α3, and α4a subunit mRNA levels were decreased due to a splicing defect. We found that Dhx37 can interact with GlyR α1, α3, and α4a transcripts but not with the GlyR α2 subunit mRNA. Overexpression of GlyR α1, α3, or α4a subunits in Dhx37-deficient embryos restored normal behavior. Conversely, antisense-mediated knockdown of multiple GlyR α subunits in wild-type embryos was required to recapitulate the Dhx37 mutant phenotype. These results indicate that Dhx37 is specifically required for the biogenesis of a subset of GlyR α subunit mRNAs, thereby regulating glycinergic synaptic transmission and associated motor behaviors. To our knowledge, this is the first identification of pathologically relevant substrates for an RNA helicase.
Collapse
|
36
|
Distinct phenotypes in zebrafish models of human startle disease. Neurobiol Dis 2013; 60:139-51. [PMID: 24029548 PMCID: PMC3972633 DOI: 10.1016/j.nbd.2013.09.002] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2013] [Revised: 08/13/2013] [Accepted: 09/01/2013] [Indexed: 11/21/2022] Open
Abstract
Startle disease is an inherited neurological disorder that causes affected individuals to suffer noise- or touch-induced non-epileptic seizures, excessive muscle stiffness and neonatal apnea episodes. Mutations known to cause startle disease have been identified in glycine receptor subunit (GLRA1 and GLRB) and glycine transporter (SLC6A5) genes, which serve essential functions at glycinergic synapses. Despite the significant successes in identifying startle disease mutations, many idiopathic cases remain unresolved. Exome sequencing in these individuals will identify new candidate genes. To validate these candidate disease genes, zebrafish is an ideal choice due to rapid knockdown strategies, accessible embryonic stages, and stereotyped behaviors. The only existing zebrafish model of startle disease, bandoneon (beo), harbors point mutations in glrbb (one of two zebrafish orthologs of human GLRB) that cause compromised glycinergic transmission and touch-induced bilateral muscle contractions. In order to further develop zebrafish as a model for startle disease, we sought to identify common phenotypic outcomes of knocking down zebrafish orthologs of two known startle disease genes, GLRA1 and GLRB, using splice site-targeted morpholinos. Although both morphants were expected to result in phenotypes similar to the zebrafish beo mutant, our direct comparison demonstrated that while both glra1 and glrbb morphants exhibited embryonic spasticity, only glrbb morphants exhibited bilateral contractions characteristic of beo mutants. Likewise, zebrafish over-expressing a dominant startle disease mutation (GlyR α1(R271Q)) exhibited spasticity but not bilateral contractions. Since GlyR βb can interact with GlyR α subunits 2-4 in addition to GlyR α1, loss of the GlyR βb subunit may produce more severe phenotypes by affecting multiple GlyR subtypes. Indeed, immunohistochemistry of glra1 morphants suggests that in zebrafish, alternate GlyR α subunits can compensate for the loss of the GlyR α1 subunit. To address the potential for interplay among GlyR subunits during development, we quantified the expression time-course for genes known to be critical to glycinergic synapse function. We found that GlyR α2, α3 and α4a are expressed in the correct temporal pattern and could compensate for the loss of the GlyR α1 subunit. Based on our findings, future studies that aim to model candidate startle disease genes in zebrafish should include measures of spasticity and synaptic development.
Collapse
|
37
|
Mirat O, Sternberg JR, Severi KE, Wyart C. ZebraZoom: an automated program for high-throughput behavioral analysis and categorization. Front Neural Circuits 2013; 7:107. [PMID: 23781175 PMCID: PMC3679480 DOI: 10.3389/fncir.2013.00107] [Citation(s) in RCA: 67] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2013] [Accepted: 05/21/2013] [Indexed: 11/13/2022] Open
Abstract
The zebrafish larva stands out as an emergent model organism for translational studies involving gene or drug screening thanks to its size, genetics, and permeability. At the larval stage, locomotion occurs in short episodes punctuated by periods of rest. Although phenotyping behavior is a key component of large-scale screens, it has not yet been automated in this model system. We developed ZebraZoom, a program to automatically track larvae and identify maneuvers for many animals performing discrete movements. Our program detects each episodic movement and extracts large-scale statistics on motor patterns to produce a quantification of the locomotor repertoire. We used ZebraZoom to identify motor defects induced by a glycinergic receptor antagonist. The analysis of the blind mutant atoh7 revealed small locomotor defects associated with the mutation. Using multiclass supervised machine learning, ZebraZoom categorized all episodes of movement for each larva into one of three possible maneuvers: slow forward swim, routine turn, and escape. ZebraZoom reached 91% accuracy for categorization of stereotypical maneuvers that four independent experimenters unanimously identified. For all maneuvers in the data set, ZebraZoom agreed with four experimenters in 73.2-82.5% of cases. We modeled the series of maneuvers performed by larvae as Markov chains and observed that larvae often repeated the same maneuvers within a group. When analyzing subsequent maneuvers performed by different larvae, we found that larva-larva interactions occurred as series of escapes. Overall, ZebraZoom reached the level of precision found in manual analysis but accomplished tasks in a high-throughput format necessary for large screens.
Collapse
Affiliation(s)
- Olivier Mirat
- Centre de Recherche de l'Institut du Cerveau et de la Moelle Épinière, UPMC, Inserm UMR S975, CNRS UMR 7225, Fondation ICM, Campus Hospitalier Pitié Salpétrière Paris, France ; Université Paris Descartes Paris, France
| | | | | | | |
Collapse
|
38
|
Yamanaka I, Miki M, Asakawa K, Kawakami K, Oda Y, Hirata H. Glycinergic transmission and postsynaptic activation of CaMKII are required for glycine receptor clusteringin vivo. Genes Cells 2013; 18:211-24. [DOI: 10.1111/gtc.12032] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2012] [Accepted: 11/29/2012] [Indexed: 02/06/2023]
Affiliation(s)
- Iori Yamanaka
- Division of Biological Science; Graduate School of Science; Nagoya University; Nagoya; 464-8602; Japan
| | - Mariko Miki
- Division of Biological Science; Graduate School of Science; Nagoya University; Nagoya; 464-8602; Japan
| | | | | | - Yoichi Oda
- Division of Biological Science; Graduate School of Science; Nagoya University; Nagoya; 464-8602; Japan
| | | |
Collapse
|
39
|
Horstick EJ, Linsley JW, Dowling JJ, Hauser MA, McDonald KK, Ashley-Koch A, Saint-Amant L, Satish A, Cui WW, Zhou W, Sprague SM, Stamm DS, Powell CM, Speer MC, Franzini-Armstrong C, Hirata H, Kuwada JY. Stac3 is a component of the excitation-contraction coupling machinery and mutated in Native American myopathy. Nat Commun 2013; 4:1952. [PMID: 23736855 PMCID: PMC4056023 DOI: 10.1038/ncomms2952] [Citation(s) in RCA: 174] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2012] [Accepted: 04/30/2013] [Indexed: 11/09/2022] Open
Abstract
Excitation-contraction coupling, the process that regulates contractions by skeletal muscles, transduces changes in membrane voltage by activating release of Ca(2+) from internal stores to initiate muscle contraction. Defects in excitation-contraction coupling are associated with muscle diseases. Here we identify Stac3 as a novel component of the excitation-contraction coupling machinery. Using a zebrafish genetic screen, we generate a locomotor mutation that is mapped to stac3. We provide electrophysiological, Ca(2+) imaging, immunocytochemical and biochemical evidence that Stac3 participates in excitation-contraction coupling in muscles. Furthermore, we reveal that a mutation in human STAC3 is the genetic basis of the debilitating Native American myopathy (NAM). Analysis of NAM stac3 in zebrafish shows that the NAM mutation decreases excitation-contraction coupling. These findings enhance our understanding of both excitation-contraction coupling and the pathology of myopathies.
Collapse
Affiliation(s)
- Eric J. Horstick
- Department of Molecular, Cellular and Developmental Biology, University of Michigan, Ann Arbor, MI 48109, USA
| | - Jeremy W. Linsley
- Cell and Molecular Biology Program, University of Michigan, Ann Arbor, MI 48109, USA
| | - James J. Dowling
- Department of Pediatrics, University of Michigan Medical Center, Ann Arbor, MI 48109, USA
| | - Michael A. Hauser
- Departments of Medicine and Ophthalmology, Duke University Medical Center, Durham, NC 27710, USA
| | - Kristin K. McDonald
- Departments of Medicine and Ophthalmology, Duke University Medical Center, Durham, NC 27710, USA
| | - Allison Ashley-Koch
- Departments of Medicine and Ophthalmology, Duke University Medical Center, Durham, NC 27710, USA
| | - Louis Saint-Amant
- Department of Molecular, Cellular and Developmental Biology, University of Michigan, Ann Arbor, MI 48109, USA
- Departement de Pathologie et Biologie Cellulaire, Universite de Montreal, Montreal, Canada H3T 1J4
| | - Akhila Satish
- Department of Molecular, Cellular and Developmental Biology, University of Michigan, Ann Arbor, MI 48109, USA
| | - Wilson W. Cui
- Cell and Molecular Biology Program, University of Michigan, Ann Arbor, MI 48109, USA
| | - Weibin Zhou
- Department of Molecular, Cellular and Developmental Biology, University of Michigan, Ann Arbor, MI 48109, USA
- Life Science Institute, University of Michigan, Ann Arbor, MI 48109, USA
| | - Shawn M. Sprague
- Department of Molecular, Cellular and Developmental Biology, University of Michigan, Ann Arbor, MI 48109, USA
| | - Demetra S. Stamm
- Department of Internal Medicine, University of California, Davis, Sacramento, CA 95817, USA
| | - Cynthia M. Powell
- Departments of Pediatrics and Genetics, The University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Marcy C. Speer
- Center for Human Genetics, Duke University, Durham, NC 27710, USA
| | - Clara Franzini-Armstrong
- Department of Cell and Developmental Biology, University of Pennsylvania School of Medicine, Philadelphia, PA 19104, USA
| | - Hiromi Hirata
- National Institute of Genetics, Mishima 411-8540, Japan
| | - John Y. Kuwada
- Department of Molecular, Cellular and Developmental Biology, University of Michigan, Ann Arbor, MI 48109, USA
- Cell and Molecular Biology Program, University of Michigan, Ann Arbor, MI 48109, USA
| |
Collapse
|
40
|
James VM, Bode A, Chung SK, Gill JL, Nielsen M, Cowan FM, Vujic M, Thomas RH, Rees MI, Harvey K, Keramidas A, Topf M, Ginjaar I, Lynch JW, Harvey RJ. Novel missense mutations in the glycine receptor β subunit gene (GLRB) in startle disease. Neurobiol Dis 2012; 52:137-49. [PMID: 23238346 PMCID: PMC3581774 DOI: 10.1016/j.nbd.2012.12.001] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2012] [Revised: 11/26/2012] [Accepted: 12/03/2012] [Indexed: 02/03/2023] Open
Abstract
Startle disease is a rare, potentially fatal neuromotor disorder characterized by exaggerated startle reflexes and hypertonia in response to sudden unexpected auditory, visual or tactile stimuli. Mutations in the GlyR α(1) subunit gene (GLRA1) are the major cause of this disorder, since remarkably few individuals with mutations in the GlyR β subunit gene (GLRB) have been found to date. Systematic DNA sequencing of GLRB in individuals with hyperekplexia revealed new missense mutations in GLRB, resulting in M177R, L285R and W310C substitutions. The recessive mutation M177R results in the insertion of a positively-charged residue into a hydrophobic pocket in the extracellular domain, resulting in an increased EC(50) and decreased maximal responses of α(1)β GlyRs. The de novo mutation L285R results in the insertion of a positively-charged side chain into the pore-lining 9' position. Mutations at this site are known to destabilize the channel closed state and produce spontaneously active channels. Consistent with this, we identified a leak conductance associated with spontaneous GlyR activity in cells expressing α(1)β(L285R) GlyRs. Peak currents were also reduced for α(1)β(L285R) GlyRs although glycine sensitivity was normal. W310C was predicted to interfere with hydrophobic side-chain stacking between M1, M2 and M3. We found that W310C had no effect on glycine sensitivity, but reduced maximal currents in α(1)β GlyRs in both homozygous (α(1)β(W310C)) and heterozygous (α(1)ββ(W310C)) stoichiometries. Since mild startle symptoms were reported in W310C carriers, this may represent an example of incomplete dominance in startle disease, providing a potential genetic explanation for the 'minor' form of hyperekplexia.
Collapse
Affiliation(s)
- Victoria M James
- Department of Pharmacology, UCL School of Pharmacy, 29-39 Brunswick Square, London WC1N 1AX, United Kingdom
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
41
|
Chung SK, Bode A, Cushion TD, Thomas RH, Hunt C, Wood SE, Pickrell WO, Drew CJG, Yamashita S, Shiang R, Leiz S, Longardt AC, Longhardt AC, Raile V, Weschke B, Puri RD, Verma IC, Harvey RJ, Ratnasinghe DD, Parker M, Rittey C, Masri A, Lingappa L, Howell OW, Vanbellinghen JF, Mullins JG, Lynch JW, Rees MI. GLRB is the third major gene of effect in hyperekplexia. Hum Mol Genet 2012. [PMID: 23184146 DOI: 10.1093/hmg/dds498] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Glycinergic neurotransmission is a major inhibitory influence in the CNS and its disruption triggers a paediatric and adult startle disorder, hyperekplexia. The postsynaptic α(1)-subunit (GLRA1) of the inhibitory glycine receptor (GlyR) and the cognate presynaptic glycine transporter (SLC6A5/GlyT2) are well-established genes of effect in hyperekplexia. Nevertheless, 52% of cases (117 from 232) remain gene negative and unexplained. Ligand-gated heteropentameric GlyRs form chloride ion channels that contain the α(1) and β-subunits (GLRB) in a 2α(1):3β configuration and they form the predominant population of GlyRs in the postnatal and adult human brain, brainstem and spinal cord. We screened GLRB through 117 GLRA1- and SLC6A5-negative hyperekplexia patients using a multiplex-polymerase chain reaction and Sanger sequencing approach. The screening identified recessive and dominant GLRB variants in 12 unrelated hyperekplexia probands. This primarily yielded homozygous null mutations, with nonsense (n = 3), small indel (n = 1), a large 95 kb deletion (n = 1), frameshifts (n = 1) and one recurrent splicing variant found in four cases. A further three cases were found with two homozygous and one dominant GLRB missense mutations. We provide strong evidence for the pathogenicity of GLRB mutations using splicing assays, deletion mapping, cell-surface biotinylation, expression studies and molecular modelling. This study describes the definitive assignment of GLRB as the third major gene for hyperekplexia and impacts on the genetic stratification and biological causation of this neonatal/paediatric disorder. Driven principally by consanguineous homozygosity of GLRB mutations, the study reveals long-term additive phenotypic outcomes for affected cases such as severe apnoea attacks, learning difficulties and developmental delay.
Collapse
Affiliation(s)
- Seo-Kyung Chung
- Neurology Research and Molecular Neuroscience, Institute of Life Science, Swansea University, Swansea SA2 8PP, UK.
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
42
|
Wolman M, Granato M. Behavioral genetics in larval zebrafish: learning from the young. Dev Neurobiol 2012; 72:366-72. [PMID: 22328273 DOI: 10.1002/dneu.20872] [Citation(s) in RCA: 62] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Deciphering the genetic code that determines how the vertebrate nervous system assembles into neural circuits that ultimately control behavior is a fascinating and challenging question in modern neurobiology. Because of the complexity of this problem, successful strategies require a simple yet focused experimental approach without limiting the scope of the discovery. Unbiased, large-scale forward genetic screens in invertebrate organisms have yielded great insight into the genetic regulation of neural circuit assembly and function. For many reasons, this highly successful approach has been difficult to recapitulate in the behavioral neuroscience field's classic vertebrate model organisms-rodents. Here, we discuss how larval zebrafish provide a promising model system to which we can apply the design of invertebrate behavior-based screens to reveal the genetic mechanisms critical for neural circuit assembly and function in vertebrates.
Collapse
Affiliation(s)
- Marc Wolman
- Department of Cell and Developmental Biology, University of Pennsylvania School of Medicine, Philadelphia, PA 19104-6058, USA
| | | |
Collapse
|
43
|
Roy NM, Arpie B, Lugo J, Linney E, Levin ED, Cerutti D. Brief embryonic strychnine exposure in zebrafish causes long-term adult behavioral impairment with indications of embryonic synaptic changes. Neurotoxicol Teratol 2012; 34:587-91. [PMID: 23022260 DOI: 10.1016/j.ntt.2012.08.001] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2011] [Revised: 08/01/2012] [Accepted: 08/01/2012] [Indexed: 10/28/2022]
Abstract
Zebrafish provide a powerful model of the impacts of embryonic toxicant exposure on neural development that may result in long-term behavioral dysfunction. In this study, zebrafish embryos were treated with 1.5mM strychnine for short embryonic time windows to induce transient changes in inhibitory neural signaling, and were subsequently raised in untreated water until adulthood. PCR analysis showed indications that strychnine exposure altered expression of some genes related to glycinergic, GABAergic and glutamatergic neuronal synapses during embryonic development. In adulthood, treated fish showed significant changes in swimming speed and tank diving behavior compared to controls. Taken together, these data show that a short embryonic exposure to a neurotoxicant can alter development of neural synapses and lead to changes in adult behavior.
Collapse
Affiliation(s)
- Nicole M Roy
- Department of Biology, Sacred Heart University, Fairfield, CT, USA.
| | | | | | | | | | | |
Collapse
|
44
|
Low SE, Woods IG, Lachance M, Ryan J, Schier AF, Saint-Amant L. Touch responsiveness in zebrafish requires voltage-gated calcium channel 2.1b. J Neurophysiol 2012; 108:148-59. [PMID: 22490555 DOI: 10.1152/jn.00839.2011] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The molecular and physiological basis of the touch-unresponsive zebrafish mutant fakir has remained elusive. Here we report that the fakir phenotype is caused by a missense mutation in the gene encoding voltage-gated calcium channel 2.1b (CACNA1Ab). Injection of RNA encoding wild-type CaV2.1 restores touch responsiveness in fakir mutants, whereas knockdown of CACNA1Ab via morpholino oligonucleotides recapitulates the fakir mutant phenotype. Fakir mutants display normal current-evoked synaptic communication at the neuromuscular junction but have attenuated touch-evoked activation of motor neurons. NMDA-evoked fictive swimming is not affected by the loss of CaV2.1b, suggesting that this channel is not required for motor pattern generation. These results, coupled with the expression of CACNA1Ab by sensory neurons, suggest that CaV2.1b channel activity is necessary for touch-evoked activation of the locomotor network in zebrafish.
Collapse
Affiliation(s)
- Sean E Low
- Départment de Pathologie et Biologie Cellulaire, Groupe de Recherche sur le Système Nerveux Central et Centre d'Excellence en Neuromique de l'Université de Montéral, Université de Montréal, Montreal, Quebec, Canada
| | | | | | | | | | | |
Collapse
|
45
|
Stewart AM, Desmond D, Kyzar E, Gaikwad S, Roth A, Riehl R, Collins C, Monnig L, Green J, Kalueff AV. Perspectives of zebrafish models of epilepsy: What, how and where next? Brain Res Bull 2012; 87:135-43. [DOI: 10.1016/j.brainresbull.2011.11.020] [Citation(s) in RCA: 64] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2011] [Revised: 11/20/2011] [Accepted: 11/25/2011] [Indexed: 10/14/2022]
|
46
|
Côté S, Drapeau P. Regulation of spinal interneuron differentiation by the paracrine action of glycine. Dev Neurobiol 2012; 72:208-14. [PMID: 22234938 PMCID: PMC4005792 DOI: 10.1002/dneu.20972] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Glycine and γ-aminobutyric acid (GABA) are depolarizing during early development but the purpose is unclear. We tested the effect of altering glycine signaling in zebrafish embryos by overexpressing the potassium-chloride co-transporter type 2 (KCC2) to reverse the chloride gradient or by blocking glycine receptors with strychnine or by selectively knocking down the embryonic glycine receptor (GlyR KD). Using a variety of markers we observed in all three cases a reduction of all types of spinal interneuron populations examined, indicating that glycine modulates their overall differentiation rather than choice of cell fate. Other cell populations (motor, sensory, and glial cells) were unaffected. As glycine appeared to act preceding neural and synaptic development, we examined the bandoneon (beo) mutant in which glycine receptors are functional but not clustered at synapses. Neural populations in beo embryos appeared normal, suggesting a paracrine action of circulating glycine in promoting interneuron differentiation.
Collapse
Affiliation(s)
- Sebastien Côté
- Department of Pathology and Cell Biology and Groupe de recherche sur le système nerveux central, University of Montreal, Montreal, QC H3C 3J7, Canada
| | | |
Collapse
|
47
|
Airhart MJ, Lee DH, Wilson TD, Miller BE, Miller MN, Skalko RG, Monaco PJ. Adverse effects of serotonin depletion in developing zebrafish. Neurotoxicol Teratol 2012; 34:152-60. [DOI: 10.1016/j.ntt.2011.08.008] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2010] [Revised: 08/10/2011] [Accepted: 08/15/2011] [Indexed: 11/17/2022]
|
48
|
Zebrafish: a model for the study of addiction genetics. Hum Genet 2011; 131:977-1008. [PMID: 22207143 DOI: 10.1007/s00439-011-1128-0] [Citation(s) in RCA: 82] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2011] [Accepted: 12/11/2011] [Indexed: 12/20/2022]
Abstract
Drug abuse and dependence are multifaceted disorders with complex genetic underpinnings. Identifying specific genetic correlates is challenging and may be more readily accomplished by defining endophenotypes specific for addictive disorders. Symptoms and syndromes, including acute drug response, consumption, preference, and withdrawal, are potential endophenotypes characterizing addiction that have been investigated using model organisms. We present a review of major genes involved in serotonergic, dopaminergic, GABAergic, and adrenoreceptor signaling that are considered to be directly involved in nicotine, opioid, cannabinoid, and ethanol use and dependence. The zebrafish genome encodes likely homologs of the vast majority of these loci. We also review the known expression patterns of these genes in zebrafish. The information presented in this review provides support for the use of zebrafish as a viable model for studying genetic factors related to drug addiction. Expansion of investigations into drug response using model organisms holds the potential to advance our understanding of drug response and addiction in humans.
Collapse
|
49
|
Hirata H, Wen H, Kawakami Y, Naganawa Y, Ogino K, Yamada K, Saint-Amant L, Low SE, Cui WW, Zhou W, Sprague SM, Asakawa K, Muto A, Kawakami K, Kuwada JY. Connexin 39.9 protein is necessary for coordinated activation of slow-twitch muscle and normal behavior in zebrafish. J Biol Chem 2011; 287:1080-9. [PMID: 22075003 DOI: 10.1074/jbc.m111.308205] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
In many tissues and organs, connexin proteins assemble between neighboring cells to form gap junctions. These gap junctions facilitate direct intercellular communication between adjoining cells, allowing for the transmission of both chemical and electrical signals. In rodents, gap junctions are found in differentiating myoblasts and are important for myogenesis. Although gap junctions were once believed to be absent from differentiated skeletal muscle in mammals, recent studies in teleosts revealed that differentiated muscle does express connexins and is electrically coupled, at least at the larval stage. These findings raised questions regarding the functional significance of gap junctions in differentiated muscle. Our analysis of gap junctions in muscle began with the isolation of a zebrafish motor mutant that displayed weak coiling at day 1 of development, a behavior known to be driven by slow-twitch muscle (slow muscle). We identified a missense mutation in the gene encoding Connexin 39.9. In situ hybridization found connexin 39.9 to be expressed by slow muscle. Paired muscle recordings uncovered that wild-type slow muscles are electrically coupled, whereas mutant slow muscles are not. The further examination of cellular activity revealed aberrant, arrhythmic touch-evoked Ca(2+) transients in mutant slow muscle and a reduction in the number of muscle fibers contracting in response to touch in mutants. These results indicate that Connexin 39.9 facilitates the spreading of neuronal inputs, which is irregular during motor development, beyond the muscle cells and that gap junctions play an essential role in the efficient recruitment of slow muscle fibers.
Collapse
Affiliation(s)
- Hiromi Hirata
- Center for Frontier Research, National Institute of Genetics, Mishima 411-8540, Japan.
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
50
|
Abstract
A central goal of modern neuroscience is to obtain a mechanistic understanding of higher brain functions under healthy and diseased conditions. Addressing this challenge requires rigorous experimental and theoretical analysis of neuronal circuits. Recent advances in optogenetics, high-resolution in vivo imaging, and reconstructions of synaptic wiring diagrams have created new opportunities to achieve this goal. To fully harness these methods, model organisms should allow for a combination of genetic and neurophysiological approaches in vivo. Moreover, the brain should be small in terms of neuron numbers and physical size. A promising vertebrate organism is the zebrafish because it is small, it is transparent at larval stages and it offers a wide range of genetic tools and advantages for neurophysiological approaches. Recent studies have highlighted the potential of zebrafish for exhaustive measurements of neuronal activity patterns, for manipulations of defined cell types in vivo and for studies of causal relationships between circuit function and behavior. In this article, we summarize background information on the zebrafish as a model in modern systems neuroscience and discuss recent results.
Collapse
Affiliation(s)
- Rainer W Friedrich
- Friedrich Miescher Institute for Biomedical Research, Maulbeerstr. 66, CH-4058 Basel, Switzerland.
| | | | | |
Collapse
|