1
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Zhang Q, Wu T, Luo C, Xie H, Wang D, Peng J, Wu K, Huang W. Ecotoxicological risk assessment of the novel psychoactive substance Esketamine: Emphasis on fish skeletal, behavioral, and vascular development. JOURNAL OF HAZARDOUS MATERIALS 2024; 480:135823. [PMID: 39278034 DOI: 10.1016/j.jhazmat.2024.135823] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/12/2024] [Revised: 09/08/2024] [Accepted: 09/10/2024] [Indexed: 09/17/2024]
Abstract
Novel psychoactive substances (NPS), such as Esketamine (Esket), often contaminate the aquatic ecosystems following human consumption, raising concerns about the residues and potential ecological hazards to non-target organisms. The study used zebrafish as a model organism to investigate the developmental toxicity and ecotoxicological effects of acute Esket exposure. Our findings demonstrate that exposure to Esket significantly affected the early development and angiogenesis of zebrafish embryos/larvae. The mandible length was significantly decreased, and the angles between the pharyngeal arch cartilages were narrowed compared to the control group (all P < 0.05). Additionally, Esket resulted in a decrease of 47.6-89.8 % in the number of neural crest cells (NCC). Transcriptome analysis indicated altered expression of genes associated with cartilage and osteoblast growth. Moreover, Esket significantly inhibited swimming ability in zebrafish larvae and was accompanied by behavioral abnormalities and molecular alterations in the brain. Potential mechanisms underlying Esket-induced behavioral disorders involve neurotransmitter system impairment, abnormal cartilage development and function, aberrant vascular development, as well as perturbations in oxidative stress and apoptosis signaling pathways. Notably, the dysregulation of skeleton development through the bone morphogenetic protein (BMP) signaling pathway is identified as the primary mechanistic behind Esket-induced behavioral disorder. This study enhances our understanding of Esket's ecotoxicology profile and provides a comprehensive assessment of the environmental risks associated with NPS.
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Affiliation(s)
- Qiong Zhang
- Department of Preventive Medicine, Shantou University Medical College, Shantou 515041, Guangdong, PR China
| | - Tianjie Wu
- Department of Anaesthesiology, Shantou Central Hospital, Affiliated Shantou Hospital of Sun Yat-Sen University, Shantou 515041, Guangdong, PR China
| | - Congying Luo
- Department of Preventive Medicine, Shantou University Medical College, Shantou 515041, Guangdong, PR China
| | - Han Xie
- Department of Preventive Medicine, Shantou University Medical College, Shantou 515041, Guangdong, PR China
| | - Dinghui Wang
- Department of Preventive Medicine, Shantou University Medical College, Shantou 515041, Guangdong, PR China
| | - Jiajun Peng
- Department of Preventive Medicine, Shantou University Medical College, Shantou 515041, Guangdong, PR China
| | - Kusheng Wu
- Department of Preventive Medicine, Shantou University Medical College, Shantou 515041, Guangdong, PR China.
| | - Wenlong Huang
- Department of Forensic Medicine, Shantou University Medical College, Shantou 515041, Guangdong, PR China.
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2
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Wyart C, Carbo-Tano M, Cantaut-Belarif Y, Orts-Del'Immagine A, Böhm UL. Cerebrospinal fluid-contacting neurons: multimodal cells with diverse roles in the CNS. Nat Rev Neurosci 2023; 24:540-556. [PMID: 37558908 DOI: 10.1038/s41583-023-00723-8] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/26/2023] [Indexed: 08/11/2023]
Abstract
The cerebrospinal fluid (CSF) is a complex solution that circulates around the CNS, and whose composition changes as a function of an animal's physiological state. Ciliated neurons that are bathed in the CSF - and thus referred to as CSF-contacting neurons (CSF-cNs) - are unusual polymodal interoceptive neurons. As chemoreceptors, CSF-cNs respond to variations in pH and osmolarity and to bacterial metabolites in the CSF. Their activation during infections of the CNS results in secretion of compounds to enhance host survival. As mechanosensory neurons, CSF-cNs operate together with an extracellular proteinaceous polymer known as the Reissner fibre to detect compression during spinal curvature. Once activated, CSF-cNs inhibit motor neurons, premotor excitatory neurons and command neurons to enhance movement speed and stabilize posture. At longer timescales, CSF-cNs instruct morphogenesis throughout life via the release of neuropeptides that act over long distances on skeletal muscle. Finally, recent evidence suggests that mouse CSF-cNs may act as neural stem cells in the spinal cord, inspiring new paths of investigation for repair after injury.
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Affiliation(s)
- Claire Wyart
- Institut du Cerveau (ICM), INSERM U1127, UMR CNRS 7225 Paris, Sorbonne Université, Paris, France.
| | - Martin Carbo-Tano
- Institut du Cerveau (ICM), INSERM U1127, UMR CNRS 7225 Paris, Sorbonne Université, Paris, France
| | - Yasmine Cantaut-Belarif
- Institut du Cerveau (ICM), INSERM U1127, UMR CNRS 7225 Paris, Sorbonne Université, Paris, France
| | | | - Urs L Böhm
- NeuroCure Cluster of Excellence, Charité Universitätsmedizin Berlin, Berlin, Germany
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3
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Sengupta M, Bagnall MW. Spinal Interneurons: Diversity and Connectivity in Motor Control. Annu Rev Neurosci 2023; 46:79-99. [PMID: 36854318 DOI: 10.1146/annurev-neuro-083122-025325] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/02/2023]
Abstract
The spinal cord is home to the intrinsic networks for locomotion. An animal in which the spinal cord has been fully severed from the brain can still produce rhythmic, patterned locomotor movements as long as some excitatory drive is provided, such as physical, pharmacological, or electrical stimuli. Yet it remains a challenge to define the underlying circuitry that produces these movements because the spinal cord contains a wide variety of neuron classes whose patterns of interconnectivity are still poorly understood. Computational models of locomotion accordingly rely on untested assumptions about spinal neuron network element identity and connectivity. In this review, we consider the classes of spinal neurons, their interconnectivity, and the significance of their circuit connections along the long axis of the spinal cord. We suggest several lines of analysis to move toward a definitive understanding of the spinal network.
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Affiliation(s)
- Mohini Sengupta
- Department of Neuroscience, Washington University in St. Louis, St. Louis, Missouri, USA;
| | - Martha W Bagnall
- Department of Neuroscience, Washington University in St. Louis, St. Louis, Missouri, USA;
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4
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Wilson AC, Sweeney LB. Spinal cords: Symphonies of interneurons across species. Front Neural Circuits 2023; 17:1146449. [PMID: 37180760 PMCID: PMC10169611 DOI: 10.3389/fncir.2023.1146449] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2023] [Accepted: 03/23/2023] [Indexed: 05/16/2023] Open
Abstract
Vertebrate movement is orchestrated by spinal inter- and motor neurons that, together with sensory and cognitive input, produce dynamic motor behaviors. These behaviors vary from the simple undulatory swimming of fish and larval aquatic species to the highly coordinated running, reaching and grasping of mice, humans and other mammals. This variation raises the fundamental question of how spinal circuits have changed in register with motor behavior. In simple, undulatory fish, exemplified by the lamprey, two broad classes of interneurons shape motor neuron output: ipsilateral-projecting excitatory neurons, and commissural-projecting inhibitory neurons. An additional class of ipsilateral inhibitory neurons is required to generate escape swim behavior in larval zebrafish and tadpoles. In limbed vertebrates, a more complex spinal neuron composition is observed. In this review, we provide evidence that movement elaboration correlates with an increase and specialization of these three basic interneuron types into molecularly, anatomically, and functionally distinct subpopulations. We summarize recent work linking neuron types to movement-pattern generation across fish, amphibians, reptiles, birds and mammals.
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Affiliation(s)
| | - Lora B. Sweeney
- Institute of Science and Technology Austria (IST Austria), Klosterneuburg, Lower Austria, Austria
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5
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Lysko DE, Talbot WS. Unmyelinated sensory neurons use Neuregulin signals to promote myelination of interneurons in the CNS. Cell Rep 2022; 41:111669. [PMID: 36384112 PMCID: PMC9719401 DOI: 10.1016/j.celrep.2022.111669] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2022] [Revised: 09/06/2022] [Accepted: 10/25/2022] [Indexed: 11/17/2022] Open
Abstract
The signaling mechanisms neurons use to modulate myelination of circuits in the central nervous system (CNS) are only partly understood. Through analysis of isoform-specific neuregulin1 (nrg1) mutants in zebrafish, we demonstrate that nrg1 type II is an important regulator of myelination of two classes of spinal cord interneurons. Surprisingly, nrg1 type II expression is prominent in unmyelinated Rohon-Beard sensory neurons, whereas myelination of neighboring interneurons is reduced in nrg1 type II mutants. Cell-type-specific loss-of-function studies indicate that nrg1 type II is required in Rohon-Beard neurons to signal to other neurons, not oligodendrocytes, to modulate spinal cord myelination. Together, our data support a model in which unmyelinated neurons express Nrg1 type II proteins to regulate myelination of neighboring neurons, a mode of action that may coordinate the functions of unmyelinated and myelinated neurons in the CNS.
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Affiliation(s)
- Daniel E Lysko
- Department of Developmental Biology, Stanford University, Stanford, CA 94305, USA
| | - William S Talbot
- Department of Developmental Biology, Stanford University, Stanford, CA 94305, USA.
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6
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Li Z, Xu XZS. Chemosensation: Corollary discharge filters out self-generated chemical cues. Curr Biol 2022; 32:R788-R790. [PMID: 35882202 PMCID: PMC10903528 DOI: 10.1016/j.cub.2022.06.021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/16/2022]
Abstract
Corollary discharge allows organisms to discriminate external sensory inputs from self-generated cues. However, the underlying synaptic and molecular mechanisms are not well understood. A new study has identified a tyraminergic corollary discharge signal that extrasynaptically modulates chemosensory neurons in Caenorhabditis elegans.
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Affiliation(s)
- Zhaoyu Li
- Queensland Brain Institute, University of Queensland, St Lucia, QLD 4072, Australia.
| | - X Z Shawn Xu
- Life Sciences Institute and Department of Molecular and Integrative Physiology, University of Michigan, Ann Arbor, MI 48109, USA.
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7
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Böhm UL, Kimura Y, Kawashima T, Ahrens MB, Higashijima SI, Engert F, Cohen AE. Voltage imaging identifies spinal circuits that modulate locomotor adaptation in zebrafish. Neuron 2022; 110:1211-1222.e4. [PMID: 35104451 PMCID: PMC8989672 DOI: 10.1016/j.neuron.2022.01.001] [Citation(s) in RCA: 20] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2021] [Revised: 11/17/2021] [Accepted: 01/04/2022] [Indexed: 12/20/2022]
Abstract
Motor systems must continuously adapt their output to maintain a desired trajectory. While the spinal circuits underlying rhythmic locomotion are well described, little is known about how the network modulates its output strength. A major challenge has been the difficulty of recording from spinal neurons during behavior. Here, we use voltage imaging to map the membrane potential of large populations of glutamatergic neurons throughout the spinal cord of the larval zebrafish during fictive swimming in a virtual environment. We characterized a previously undescribed subpopulation of tonic-spiking ventral V3 neurons whose spike rate correlated with swimming strength and bout length. Optogenetic activation of V3 neurons led to stronger swimming and longer bouts but did not affect tail beat frequency. Genetic ablation of V3 neurons led to reduced locomotor adaptation. The power of voltage imaging allowed us to identify V3 neurons as a critical driver of locomotor adaptation in zebrafish.
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Affiliation(s)
- Urs L Böhm
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA 02138, USA
| | - Yukiko Kimura
- National Institutes of Natural Sciences, Okazaki Institute for Integrative Bioscience, National Institute for Physiological Sciences, Okazaki, Aichi 444-8787, Japan
| | - Takashi Kawashima
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA 20147, USA
| | - Misha B Ahrens
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA 20147, USA
| | - Shin-Ichi Higashijima
- National Institutes of Natural Sciences, Okazaki Institute for Integrative Bioscience, National Institute for Physiological Sciences, Okazaki, Aichi 444-8787, Japan
| | - Florian Engert
- Department of Molecular and Cellular Biology, Harvard University, Cambridge, MA 02138, USA
| | - Adam E Cohen
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA 02138, USA; Department of Physics, Harvard University, Cambridge, MA 02138, USA.
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8
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Barnaby W, Dorman Barclay HE, Nagarkar A, Perkins M, Teicher G, Trapani JG, Downes GB. GABAA α subunit control of hyperactive behavior in developing zebrafish. Genetics 2022; 220:6519832. [PMID: 35106556 PMCID: PMC8982038 DOI: 10.1093/genetics/iyac011] [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: 07/14/2021] [Accepted: 01/03/2022] [Indexed: 02/04/2023] Open
Abstract
GABAA receptors mediate rapid responses to the neurotransmitter gamma-aminobutyric acid and are robust regulators of the brain and spinal cord neural networks that control locomotor behaviors, such as walking and swimming. In developing zebrafish, gross pharmacological blockade of these receptors causes hyperactive swimming, which is also a feature of many zebrafish epilepsy models. Although GABAA receptors are important to control locomotor behavior, the large number of subunits and homeostatic compensatory mechanisms have challenged efforts to determine subunit-selective roles. To address this issue, we mutated each of the 8 zebrafish GABAA α subunit genes individually and in pairs using a CRISPR-Cas9 somatic inactivation approach and, then, we examined the swimming behavior of the mutants at 2 developmental stages, 48 and 96 h postfertilization. We found that disrupting the expression of specific pairs of subunits resulted in different abnormalities in swimming behavior at 48 h postfertilization. Mutation of α4 and α5 selectively resulted in longer duration swimming episodes, mutations in α3 and α4 selectively caused excess, large-amplitude body flexions (C-bends), and mutation of α3 and α5 resulted in increases in both of these measures of hyperactivity. At 96 h postfertilization, hyperactive phenotypes were nearly absent, suggesting that homeostatic compensation was able to overcome the disruption of even multiple subunits. Taken together, our results identify subunit-selective roles for GABAA α3, α4, and α5 in regulating locomotion. Given that these subunits exhibit spatially restricted expression patterns, these results provide a foundation to identify neurons and GABAergic networks that control discrete aspects of locomotor behavior.
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Affiliation(s)
- Wayne Barnaby
- Neuroscience and Behavior Graduate Program, University of Massachusetts Amherst, Amherst, MA 01003, USA,Biology Department, University of Massachusetts Amherst, Amherst, MA 01003, USA
| | | | - Akanksha Nagarkar
- Biology Department, University of Massachusetts Amherst, Amherst, MA 01003, USA
| | - Matthew Perkins
- Biology Department and Neuroscience Program, Amherst College, Amherst, MA 01002, USA
| | - Gregory Teicher
- Molecular and Cellular Biology Program, University of Massachusetts Amherst, Amherst, MA 01003, USA,Biology Department, University of Massachusetts Amherst, Amherst, MA 01003, USA
| | - Josef G Trapani
- Neuroscience and Behavior Graduate Program, University of Massachusetts Amherst, Amherst, MA 01003, USA,Biology Department and Neuroscience Program, Amherst College, Amherst, MA 01002, USA
| | - Gerald B Downes
- Neuroscience and Behavior Graduate Program, University of Massachusetts Amherst, Amherst, MA 01003, USA,Molecular and Cellular Biology Program, University of Massachusetts Amherst, Amherst, MA 01003, USA,Biology Department, University of Massachusetts Amherst, Amherst, MA 01003, USA,Corresponding author: Biology Department, Neuroscience and Behavior Graduate Program, and Molecular and Cellular Biology Graduate Program, 611 North Pleasant St., Morrill Science Center, Building 4 North, Amherst, MA 01003, USA.
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9
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Sengupta M, Daliparthi V, Roussel Y, Bui TV, Bagnall MW. Spinal V1 neurons inhibit motor targets locally and sensory targets distally. Curr Biol 2021; 31:3820-3833.e4. [PMID: 34289387 PMCID: PMC8440420 DOI: 10.1016/j.cub.2021.06.053] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2021] [Revised: 05/06/2021] [Accepted: 06/18/2021] [Indexed: 01/30/2023]
Abstract
Rostro-caudal coordination of spinal motor output is essential for locomotion. Most spinal interneurons project axons longitudinally to govern locomotor output, yet their connectivity along this axis remains unclear. In this study, we use larval zebrafish to map synaptic outputs of a major inhibitory population, V1 (Eng1+) neurons, which are implicated in dual sensory and motor functions. We find that V1 neurons exhibit long axons extending rostrally and exclusively ipsilaterally for an average of 6 spinal segments; however, they do not connect uniformly with their post-synaptic targets along the entire length of their axon. Locally, V1 neurons inhibit motor neurons (both fast and slow) and other premotor targets, including V2a, V2b, and commissural premotor neurons. In contrast, V1 neurons make robust long-range inhibitory contacts onto a dorsal horn sensory population, the commissural primary ascending neurons (CoPAs). In a computational model of the ipsilateral spinal network, we show that this pattern of short-range V1 inhibition to motor and premotor neurons underlies burst termination, which is critical for coordinated rostro-caudal propagation of the locomotor wave. We conclude that spinal network architecture in the longitudinal axis can vary dramatically, with differentially targeted local and distal connections, yielding important consequences for function.
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Affiliation(s)
- Mohini Sengupta
- Washington University School of Medicine, Department of Neuroscience, St. Louis, MO, USA
| | - Vamsi Daliparthi
- Washington University School of Medicine, Department of Neuroscience, St. Louis, MO, USA
| | - Yann Roussel
- Brain and Mind Research Institute, Centre for Neural Dynamics, Department of Biology, University of Ottawa, Ottawa, Canada; Blue Brain Project, École Polytechnique Fédérale de Lausanne, Geneve, Switzerland
| | - Tuan V Bui
- Brain and Mind Research Institute, Centre for Neural Dynamics, Department of Biology, University of Ottawa, Ottawa, Canada
| | - Martha W Bagnall
- Washington University School of Medicine, Department of Neuroscience, St. Louis, MO, USA.
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10
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Abstract
Locomotion requires the segmental coordination of activity along the body. A new study in zebrafish reveals that spinal inhibitory interneurons are wired to execute different functions depending on whether their targets are nearby or further away.
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Affiliation(s)
- Michael Jay
- Department of Neurobiology, Northwestern University, Evanston, IL 60201, USA
| | - David L McLean
- Department of Neurobiology, Northwestern University, Evanston, IL 60201, USA.
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11
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Wu MY, Carbo-Tano M, Mirat O, Lejeune FX, Roussel J, Quan FB, Fidelin K, Wyart C. Spinal sensory neurons project onto the hindbrain to stabilize posture and enhance locomotor speed. Curr Biol 2021; 31:3315-3329.e5. [PMID: 34146485 DOI: 10.1016/j.cub.2021.05.042] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2020] [Revised: 03/12/2021] [Accepted: 05/19/2021] [Indexed: 12/11/2022]
Abstract
In the spinal cord, cerebrospinal fluid-contacting neurons (CSF-cNs) are GABAergic interoceptive sensory neurons that detect spinal curvature via a functional coupling with the Reissner fiber. This mechanosensory system has recently been found to be involved in spine morphogenesis and postural control but the underlying mechanisms are not fully understood. In zebrafish, CSF-cNs project an ascending and ipsilateral axon reaching two to six segments away. Rostralmost CSF-cNs send their axons ipsilaterally into the hindbrain, a brain region containing motor nuclei and reticulospinal neurons (RSNs), which send descending motor commands to spinal circuits. Until now, the synaptic connectivity of CSF-cNs has only been investigated in the spinal cord, where they synapse onto motor neurons and premotor excitatory interneurons. The identity of CSF-cN targets in the hindbrain and the behavioral relevance of these sensory projections from the spinal cord to the hindbrain are unknown. Here, we provide anatomical and molecular evidence that rostralmost CSF-cNs synapse onto the axons of large RSNs including Mauthner cells and V2a neurons. Functional anatomy and optogenetically assisted mapping reveal that rostral CSF-cNs also synapse onto the soma and dendrites of cranial motor neurons innervating hypobranchial muscles. During acousto-vestibular evoked escape responses, ablation of rostralmost CSF-cNs results in a weaker escape response with a decreased C-bend amplitude, lower speed, and deficient postural control. Our study demonstrates that spinal sensory feedback enhances speed and stabilizes posture, and reveals a novel spinal gating mechanism acting on the output of descending commands sent from the hindbrain to the spinal cord.
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Affiliation(s)
- Ming-Yue Wu
- Sorbonne Université, Institut du Cerveau (ICM), Inserm U 1127, CNRS UMR 7225, 75013 Paris, France
| | - Martin Carbo-Tano
- Sorbonne Université, Institut du Cerveau (ICM), Inserm U 1127, CNRS UMR 7225, 75013 Paris, France.
| | - Olivier Mirat
- Sorbonne Université, Institut du Cerveau (ICM), Inserm U 1127, CNRS UMR 7225, 75013 Paris, France
| | - Francois-Xavier Lejeune
- Sorbonne Université, Institut du Cerveau (ICM), Inserm U 1127, CNRS UMR 7225, 75013 Paris, France
| | - Julian Roussel
- Sorbonne Université, Institut du Cerveau (ICM), Inserm U 1127, CNRS UMR 7225, 75013 Paris, France
| | - Feng B Quan
- Sorbonne Université, Institut du Cerveau (ICM), Inserm U 1127, CNRS UMR 7225, 75013 Paris, France
| | - Kevin Fidelin
- Sorbonne Université, Institut du Cerveau (ICM), Inserm U 1127, CNRS UMR 7225, 75013 Paris, France
| | - Claire Wyart
- Sorbonne Université, Institut du Cerveau (ICM), Inserm U 1127, CNRS UMR 7225, 75013 Paris, France.
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12
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Spatiotemporal Transition in the Role of Synaptic Inhibition to the Tail Beat Rhythm of Developing Larval Zebrafish. eNeuro 2020; 7:ENEURO.0508-18.2020. [PMID: 32005749 PMCID: PMC7029186 DOI: 10.1523/eneuro.0508-18.2020] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2018] [Revised: 01/14/2020] [Accepted: 01/16/2020] [Indexed: 11/29/2022] Open
Abstract
Significant maturation of swimming in zebrafish (Danio rerio) occurs within the first few days of life when fish transition from coiling movements to burst swimming and then to beat-and-glide swimming. This maturation occurs against a backdrop of numerous developmental changes - neurogenesis, a transition from predominantly electrical to chemical-based neurotransmission, and refinement of intrinsic properties. There is evidence that spinal locomotor circuits undergo fundamental changes as the zebrafish transitions from burst to beat-and-glide swimming. Our electrophysiological recordings confirm that the operation of spinal locomotor circuits becomes increasingly reliant on glycinergic neurotransmission for rhythmogenesis governing the rhythm of tail beats. This transition occurred at the same time that we observed a change in rhythmicity of synaptic inhibition to spinal motoneurons (MNs). When we examined whether the transition from weakly to strongly glycinergic dependent rhythmogenesis occurred at a uniform pace across the length of the spinal cord, we found that this transition occurred earlier at caudal segments than at rostral segments of the spinal cord. Furthermore, while this rhythmogenic transition occurred when fish transition from burst swimming to beat-and-glide swimming, these two transitions were not interdependent. These results suggest that there is a developmental transition in the operation of spinal locomotor circuits that is gradually set in place in the spinal cord in a caudo-rostral temporal sequence.
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13
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Wan Y, Wei Z, Looger LL, Koyama M, Druckmann S, Keller PJ. Single-Cell Reconstruction of Emerging Population Activity in an Entire Developing Circuit. Cell 2019; 179:355-372.e23. [PMID: 31564455 PMCID: PMC7055533 DOI: 10.1016/j.cell.2019.08.039] [Citation(s) in RCA: 58] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2019] [Revised: 07/03/2019] [Accepted: 08/21/2019] [Indexed: 01/04/2023]
Abstract
Animal survival requires a functioning nervous system to develop during embryogenesis. Newborn neurons must assemble into circuits producing activity patterns capable of instructing behaviors. Elucidating how this process is coordinated requires new methods that follow maturation and activity of all cells across a developing circuit. We present an imaging method for comprehensively tracking neuron lineages, movements, molecular identities, and activity in the entire developing zebrafish spinal cord, from neurogenesis until the emergence of patterned activity instructing the earliest spontaneous motor behavior. We found that motoneurons are active first and form local patterned ensembles with neighboring neurons. These ensembles merge, synchronize globally after reaching a threshold size, and finally recruit commissural interneurons to orchestrate the left-right alternating patterns important for locomotion in vertebrates. Individual neurons undergo functional maturation stereotypically based on their birth time and anatomical origin. Our study provides a general strategy for reconstructing how functioning circuits emerge during embryogenesis. VIDEO ABSTRACT.
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Affiliation(s)
- Yinan Wan
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA, USA.
| | - Ziqiang Wei
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA, USA
| | - Loren L Looger
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA, USA
| | - Minoru Koyama
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA, USA
| | - Shaul Druckmann
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA, USA; Department of Neurobiology, Stanford University, Stanford, CA, USA; Department of Psychiatry and Behavioral Sciences, Stanford University, Stanford, CA, USA
| | - Philipp J Keller
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA, USA.
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14
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Henderson KW, Menelaou E, Hale ME. Sensory neurons in the spinal cord of zebrafish and their local connectivity. CURRENT OPINION IN PHYSIOLOGY 2019. [DOI: 10.1016/j.cophys.2019.01.008] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
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15
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Jay M, McLean DL. Reconciling the functions of even-skipped interneurons during crawling, swimming, and walking. CURRENT OPINION IN PHYSIOLOGY 2019; 8:188-192. [PMID: 31667448 DOI: 10.1016/j.cophys.2019.02.003] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
In all bilaterally symmetric animals, movements across the body are coordinated by interneurons that traverse the midline. Recent work is beginning to tease apart the functional complexity of interneurons labeled by the homeodomain transcription factor even-skipped, which provide a phylogenetically-conserved source of commissural excitation during locomotion in both vertebrates and invertebrates. Here we review recent studies of the roles of even-skipped neurons during locomotion in flies (EL neurons), fishes, frogs, and mice (V0v neurons). Comparisons across species reveal commonalities, which include the functional organization of even-skipped circuits based on birth order, the link between increased muscular complexity and even-skipped neuron diversity, and the hierarchical organization of even-skipped circuits based on their control of escape versus exploratory movements. We discuss how stronger links between different species enable testable predictions to further the discovery of principles of locomotor network organization.
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Affiliation(s)
- Michael Jay
- Department of Neurobiology Northwestern University EVANSTON, IL USA
| | - David L McLean
- Department of Neurobiology Northwestern University EVANSTON, IL USA
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16
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Berg EM, Björnfors ER, Pallucchi I, Picton LD, El Manira A. Principles Governing Locomotion in Vertebrates: Lessons From Zebrafish. Front Neural Circuits 2018; 12:73. [PMID: 30271327 PMCID: PMC6146226 DOI: 10.3389/fncir.2018.00073] [Citation(s) in RCA: 54] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2018] [Accepted: 08/27/2018] [Indexed: 11/24/2022] Open
Abstract
Locomotor behaviors are critical for survival and enable animals to navigate their environment, find food and evade predators. The circuits in the brain and spinal cord that initiate and maintain such different modes of locomotion in vertebrates have been studied in numerous species for over a century. In recent decades, the zebrafish has emerged as one of the main model systems for the study of locomotion, owing to its experimental amenability, and work in zebrafish has revealed numerous new insights into locomotor circuit function. Here, we review the literature that has led to our current understanding of the neural circuits controlling swimming and escape in zebrafish. We highlight recent studies that have enriched our comprehension of key topics, such as the interactions between premotor excitatory interneurons (INs) and motoneurons (MNs), supraspinal and spinal circuits that coordinate escape maneuvers, and developmental changes in overall circuit composition. We also discuss roles for neuromodulators and sensory inputs in modifying the relative strengths of constituent circuit components to provide flexibility in zebrafish behavior, allowing the animal to accommodate changes in the environment. We aim to provide a coherent framework for understanding the circuitry in the brain and spinal cord of zebrafish that allows the animal to flexibly transition between different speeds, and modes, of locomotion.
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Affiliation(s)
- Eva M Berg
- Department of Neuroscience, Karolinska Institute (KI), Stockholm, Sweden
| | | | - Irene Pallucchi
- Department of Neuroscience, Karolinska Institute (KI), Stockholm, Sweden
| | - Laurence D Picton
- Department of Neuroscience, Karolinska Institute (KI), Stockholm, Sweden
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17
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Active mechanosensory feedback during locomotion in the zebrafish spinal cord. Curr Opin Neurobiol 2018; 52:48-53. [PMID: 29704750 DOI: 10.1016/j.conb.2018.04.010] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2018] [Revised: 03/20/2018] [Accepted: 04/07/2018] [Indexed: 11/22/2022]
Abstract
The investigation of mechanosensory feedback to locomotion has been hindered by the challenge of recording neurons in motion. Genetic accessibility and optical transparency of zebrafish larvae provide means to revisit this question. Glutamatergic Rohon-Beard (RB) and GABAergic CSF-contacting neurons (CSF-cNs) are spinal mechanosensory neurons. Recent studies combining bioluminescence, silencing and optogenetic activation show that mechanosensory neurons enhance speed and stabilize posture during locomotion. RB neurons can modulate speed by projecting onto glutamatergic premotor V2a interneurons during fast swimming, while CSF-cNs inhibit V0-v interneurons sustaining slow swimming. Sensory gating, either through inhibition of sensory interneurons (CoPA) or though the direct inhibition of primary motor neurons by CSF-cNs, mediates postural control. Advanced optical methods have shed light on the dynamics of sensorimotor integration during active locomotion unraveling implications for translational research.
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18
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Knafo S, Fidelin K, Prendergast A, Tseng PEB, Parrin A, Dickey C, Böhm UL, Figueiredo SN, Thouvenin O, Pascal-Moussellard H, Wyart C. Mechanosensory neurons control the timing of spinal microcircuit selection during locomotion. eLife 2017; 6:e25260. [PMID: 28623664 PMCID: PMC5499942 DOI: 10.7554/elife.25260] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2017] [Accepted: 06/17/2017] [Indexed: 12/22/2022] Open
Abstract
Despite numerous physiological studies about reflexes in the spinal cord, the contribution of mechanosensory feedback to active locomotion and the nature of underlying spinal circuits remains elusive. Here we investigate how mechanosensory feedback shapes active locomotion in a genetic model organism exhibiting simple locomotion-the zebrafish larva. We show that mechanosensory feedback enhances the recruitment of motor pools during active locomotion. Furthermore, we demonstrate that inputs from mechanosensory neurons increase locomotor speed by prolonging fast swimming at the expense of slow swimming during stereotyped acoustic escape responses. This effect could be mediated by distinct mechanosensory neurons. In the spinal cord, we show that connections compatible with monosynaptic inputs from mechanosensory Rohon-Beard neurons onto ipsilateral V2a interneurons selectively recruited at high speed can contribute to the observed enhancement of speed. Altogether, our study reveals the basic principles and a circuit diagram enabling speed modulation by mechanosensory feedback in the vertebrate spinal cord.
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Affiliation(s)
- Steven Knafo
- Institut du Cerveau et de la Moelle épinière (I.C.M.), Sorbonne Universités, UPMC Univ Paris 06, Inserm, CNRS, Institut du Cerveau et la Moelle épinière, Hôpital Pitié-Salpêtrière, Paris, France
- AP-HP, Hôpital Pitié-Salpêtrière, Paris, France
| | - Kevin Fidelin
- Institut du Cerveau et de la Moelle épinière (I.C.M.), Sorbonne Universités, UPMC Univ Paris 06, Inserm, CNRS, Institut du Cerveau et la Moelle épinière, Hôpital Pitié-Salpêtrière, Paris, France
| | - Andrew Prendergast
- Institut du Cerveau et de la Moelle épinière (I.C.M.), Sorbonne Universités, UPMC Univ Paris 06, Inserm, CNRS, Institut du Cerveau et la Moelle épinière, Hôpital Pitié-Salpêtrière, Paris, France
| | - Po-En Brian Tseng
- Institut du Cerveau et de la Moelle épinière (I.C.M.), Sorbonne Universités, UPMC Univ Paris 06, Inserm, CNRS, Institut du Cerveau et la Moelle épinière, Hôpital Pitié-Salpêtrière, Paris, France
| | - Alexandre Parrin
- Institut du Cerveau et de la Moelle épinière (I.C.M.), Sorbonne Universités, UPMC Univ Paris 06, Inserm, CNRS, Institut du Cerveau et la Moelle épinière, Hôpital Pitié-Salpêtrière, Paris, France
| | - Charles Dickey
- Institut du Cerveau et de la Moelle épinière (I.C.M.), Sorbonne Universités, UPMC Univ Paris 06, Inserm, CNRS, Institut du Cerveau et la Moelle épinière, Hôpital Pitié-Salpêtrière, Paris, France
| | - Urs Lucas Böhm
- Institut du Cerveau et de la Moelle épinière (I.C.M.), Sorbonne Universités, UPMC Univ Paris 06, Inserm, CNRS, Institut du Cerveau et la Moelle épinière, Hôpital Pitié-Salpêtrière, Paris, France
| | - Sophie Nunes Figueiredo
- Institut du Cerveau et de la Moelle épinière (I.C.M.), Sorbonne Universités, UPMC Univ Paris 06, Inserm, CNRS, Institut du Cerveau et la Moelle épinière, Hôpital Pitié-Salpêtrière, Paris, France
| | - Olivier Thouvenin
- Institut du Cerveau et de la Moelle épinière (I.C.M.), Sorbonne Universités, UPMC Univ Paris 06, Inserm, CNRS, Institut du Cerveau et la Moelle épinière, Hôpital Pitié-Salpêtrière, Paris, France
| | - Hugues Pascal-Moussellard
- Institut du Cerveau et de la Moelle épinière (I.C.M.), Sorbonne Universités, UPMC Univ Paris 06, Inserm, CNRS, Institut du Cerveau et la Moelle épinière, Hôpital Pitié-Salpêtrière, Paris, France
- AP-HP, Hôpital Pitié-Salpêtrière, Paris, France
| | - Claire Wyart
- Institut du Cerveau et de la Moelle épinière (I.C.M.), Sorbonne Universités, UPMC Univ Paris 06, Inserm, CNRS, Institut du Cerveau et la Moelle épinière, Hôpital Pitié-Salpêtrière, Paris, France
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19
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Abstract
Spontaneous activity represents an early, primitive form of motor activity within zebrafish embryos, providing a potential readout for identification of neuroactive compounds. However, despite use as an endpoint in chemical screens around the world, the predictive power and limitations of assays relying on spontaneous activity remain unclear. Using an improved high-content screening assay that increased throughput from 384 to 3072 wells per week, we screened a well-characterized library of 1280 pharmacologically active compounds (LOPAC1280) - 612 of which target neurotransmission - to identify which targets are detected using spontaneous activity as a readout. Results from this screen revealed that (1) 8% of the LOPAC1280 library was biologically active; (2) spontaneous activity was affected by compounds spanning a broad array of targets; (3) only 4% of compounds targeting neurotransmission impacted spontaneous activity; and (4) hypoactivity was observed for 100% of hits detected, including those that exhibit opposing mechanisms of action for the same target. Therefore, while this assay was able to rapidly identify potent neuroactive chemicals, these data suggest that spontaneous activity may lack the ability to discriminate modes of action for compounds interfering with neurotransmission, an issue that may be due to systemic uptake following waterborne exposure, persistent control variation, and/or interference with non-neurotransmission-related mechanisms.
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Affiliation(s)
- Sara M Vliet
- Environmental Toxicology Graduate Program, University of California, Riverside, CA, USA; Department of Environmental Sciences, University of California, Riverside, CA, USA
| | - Trina C Ho
- Department of Environmental Sciences, University of California, Riverside, CA, USA
| | - David C Volz
- Department of Environmental Sciences, University of California, Riverside, CA, USA.
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Bishop BH, Spence-Chorman N, Gahtan E. Three-dimensional motion tracking reveals a diving component to visual and auditory escape swims in zebrafish larvae. ACTA ACUST UNITED AC 2016; 219:3981-3987. [PMID: 27802145 DOI: 10.1242/jeb.147124] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2016] [Accepted: 10/13/2016] [Indexed: 02/03/2023]
Abstract
Escape behaviors have been studied in zebrafish by neuroscientists seeking cellular-level descriptions of neural circuits but few studies have examined vertical swimming during escapes. We analyzed three-dimensional swimming paths of zebrafish larvae during visually-evoked and auditory-evoked escapes while the fish were in a cubical tank with equal vertical and lateral range. Visually evoked escapes, elicited by sudden dimming of ambient light, consistently elicited downward spiral swimming (dives) with faster vertical than lateral movement. Auditory taps also elicited rapid escape swimming with equivalent total distance traveled but with significantly less vertical and more lateral movement. Visually evoked dives usually ended with the zebrafish hitting the bottom of the 10 cm3 tank. Therefore, visually evoked dives were also analyzed in a tubular tank with 50 cm of vertical range, and in most cases larvae reached the bottom of that tank during a 120 s dimming stimulus. Light-evoked spiral diving in zebrafish may be an innate defense reflex against specific predation threats. Since visual and auditory escapes are initially similar but dives persist only during visual escapes, our findings lay the groundwork for studying a type of decision-making within zebrafish sensorimotor circuits.
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Affiliation(s)
- Benjamin H Bishop
- Department of Psychology, Humboldt State University, 1 Harpst Street, Arcata, CA 95521, USA
| | - Nathan Spence-Chorman
- Department of Psychology, Humboldt State University, 1 Harpst Street, Arcata, CA 95521, USA
| | - Ethan Gahtan
- Department of Psychology, Humboldt State University, 1 Harpst Street, Arcata, CA 95521, USA
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21
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Hubbard JM, Böhm UL, Prendergast A, Tseng PEB, Newman M, Stokes C, Wyart C. Intraspinal Sensory Neurons Provide Powerful Inhibition to Motor Circuits Ensuring Postural Control during Locomotion. Curr Biol 2016; 26:2841-2853. [PMID: 27720623 DOI: 10.1016/j.cub.2016.08.026] [Citation(s) in RCA: 57] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2016] [Revised: 08/08/2016] [Accepted: 08/10/2016] [Indexed: 01/13/2023]
Abstract
In the vertebrate spinal cord, cerebrospinal fluid-contacting neurons (CSF-cNs) are GABAergic neurons whose functions are only beginning to unfold. Recent evidence indicates that CSF-cNs detect local spinal bending and relay this mechanosensory feedback information to motor circuits, yet many CSF-cN targets remain unknown. Using optogenetics, patterned illumination, and in vivo electrophysiology, we show here that CSF-cNs provide somatic inhibition to fast motor neurons and excitatory sensory interneurons involved in the escape circuit. Ventral CSF-cNs respond to longitudinal spinal contractions and induce large inhibitory postsynaptic currents (IPSCs) sufficient to silence spiking of their targets. Upon repetitive stimulation, these IPSCs promptly depress, enabling the mechanosensory response to the first bend to be the most effective. When CSF-cNs are silenced, postural control is compromised, resulting in rollovers during escapes. Altogether, our data demonstrate how GABAergic sensory neurons provide powerful inhibitory feedback to the escape circuit to maintain balance during active locomotion.
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Affiliation(s)
- Jeffrey Michael Hubbard
- Institut du Cerveau et de la Moelle Épinière, Hôpital Pitié Salpêtrière, 47 Boulevard de l'Hôpital, 75013 Paris, France; INSERM UMRS 1127, 75013 Paris, France; CNRS UMR 7225, 75005 Paris, France; UPMC University Paris 06, 75005 Paris, France
| | - Urs Lucas Böhm
- Institut du Cerveau et de la Moelle Épinière, Hôpital Pitié Salpêtrière, 47 Boulevard de l'Hôpital, 75013 Paris, France; INSERM UMRS 1127, 75013 Paris, France; CNRS UMR 7225, 75005 Paris, France; UPMC University Paris 06, 75005 Paris, France
| | - Andrew Prendergast
- Institut du Cerveau et de la Moelle Épinière, Hôpital Pitié Salpêtrière, 47 Boulevard de l'Hôpital, 75013 Paris, France; INSERM UMRS 1127, 75013 Paris, France; CNRS UMR 7225, 75005 Paris, France; UPMC University Paris 06, 75005 Paris, France
| | - Po-En Brian Tseng
- Institut du Cerveau et de la Moelle Épinière, Hôpital Pitié Salpêtrière, 47 Boulevard de l'Hôpital, 75013 Paris, France; INSERM UMRS 1127, 75013 Paris, France; CNRS UMR 7225, 75005 Paris, France; UPMC University Paris 06, 75005 Paris, France
| | - Morgan Newman
- Department of Genetics and Evolution, School of Biological Sciences, The University of Adelaide, Adelaide, SA 5005, Australia
| | - Caleb Stokes
- Institut du Cerveau et de la Moelle Épinière, Hôpital Pitié Salpêtrière, 47 Boulevard de l'Hôpital, 75013 Paris, France; INSERM UMRS 1127, 75013 Paris, France; CNRS UMR 7225, 75005 Paris, France; UPMC University Paris 06, 75005 Paris, France
| | - Claire Wyart
- Institut du Cerveau et de la Moelle Épinière, Hôpital Pitié Salpêtrière, 47 Boulevard de l'Hôpital, 75013 Paris, France; INSERM UMRS 1127, 75013 Paris, France; CNRS UMR 7225, 75005 Paris, France; UPMC University Paris 06, 75005 Paris, France.
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22
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Goetghebeur PJ, Swartz JE. True alignment of preclinical and clinical research to enhance success in CNS drug development: a review of the current evidence. J Psychopharmacol 2016; 30:586-94. [PMID: 27147593 DOI: 10.1177/0269881116645269] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Central nervous system pharmacological research and development has reached a critical turning point. Patients suffering from disorders afflicting the central nervous system are numerous and command significant attention from the pharmaceutical industry. However, given the numerous failures of promising drugs, many companies are no longer investing in or, indeed, are divesting from this therapeutic area. Central nervous system drug development must change in order to develop effective therapies to treat these patients. Preclinical research is a cornerstone of drug development; however, it is frequently criticised for its lack of predictive validity. Animal models and assays can be shown to be more predictive than reported and, on many occasions, the lack of thorough preclinical testing is potentially to blame for some of the clinical failures. Important factors such as translational aspects, nature of animal models, variances in acute versus chronic dosing, development of add-on therapies and understanding of the full dose-response relationship are too often neglected. Reducing the attrition rate in central nervous system drug development could be achieved by addressing these important questions before novel compounds enter the clinical phase. This review illustrates the relevance of employing these criteria to translational central nervous system research, better to ensure success in developing new drugs in this therapeutic area.
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Affiliation(s)
| | - Jina E Swartz
- CNS Therapeutic Area Unit, Takeda Development Centre Europe Ltd, London, UK
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23
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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.
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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
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