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Jukic A, Lei Z, Cebul ER, Pinter K, Mosqueda N, David S, Tarchini B, Kindt K. Presynaptic Nrxn3 is essential for ribbon-synapse assembly in hair cells. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.02.14.580267. [PMID: 38410471 PMCID: PMC10896334 DOI: 10.1101/2024.02.14.580267] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/28/2024]
Abstract
Hair cells of the inner ear rely on specialized ribbon synapses to transmit sensory information to the central nervous system. The molecules required to assemble these synapses are not fully understood. We show that Nrxn3, a presynaptic adhesion molecule, is critical for ribbon-synapse assembly in hair cells. In both mouse and zebrafish models, loss of Nrxn3 results in significantly fewer intact ribbon synapses. In zebrafish we demonstrate that a 60% loss of synapses in nrxn3 mutants dramatically reduces both presynaptic responses in hair cells and postsynaptic responses in afferent neurons. Despite a reduction in synapse function in this model, we find no deficits in the acoustic startle response, a behavior reliant on these synapses. Overall, this work demonstrates that Nrxn3 is a critical and conserved molecule required to assemble ribbon synapses. Understanding how ribbon synapses assemble is a key step towards generating novel therapies to treat forms of age-related and noise-induced hearing loss that occur due to loss of ribbon synapses.
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Affiliation(s)
- Alma Jukic
- Section on Sensory Cell Development and Function, National Institute on Deafness and Other Communication Disorders, Bethesda, MD, 20892, USA
| | - Zhengchang Lei
- Section on Sensory Cell Development and Function, National Institute on Deafness and Other Communication Disorders, Bethesda, MD, 20892, USA
| | - Elizabeth R Cebul
- Section on Sensory Cell Development and Function, National Institute on Deafness and Other Communication Disorders, Bethesda, MD, 20892, USA
| | - Katherine Pinter
- Section on Sensory Cell Development and Function, National Institute on Deafness and Other Communication Disorders, Bethesda, MD, 20892, USA
| | - Natalie Mosqueda
- Section on Sensory Cell Development and Function, National Institute on Deafness and Other Communication Disorders, Bethesda, MD, 20892, USA
| | - Sandeep David
- Section on Sensory Cell Development and Function, National Institute on Deafness and Other Communication Disorders, Bethesda, MD, 20892, USA
| | | | - Katie Kindt
- Section on Sensory Cell Development and Function, National Institute on Deafness and Other Communication Disorders, Bethesda, MD, 20892, USA
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2
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Brehm N, Wenke N, Glessner K, Haehnel-Taguchi M. Physiological responses of mechanosensory systems in the head of larval zebrafish ( Danio rerio). Front Robot AI 2023; 10:1212626. [PMID: 37583713 PMCID: PMC10423815 DOI: 10.3389/frobt.2023.1212626] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2023] [Accepted: 07/11/2023] [Indexed: 08/17/2023] Open
Abstract
The lateral line system of zebrafish consists of the anterior lateral line, with neuromasts distributed on the head, and the posterior lateral line, with neuromasts distributed on the trunk. The sensory afferent neurons are contained in the anterior and posterior lateral line ganglia, respectively. So far, the vast majority of physiological and developmental studies have focused on the posterior lateral line. However, studies that focus on the anterior lateral line, especially on its physiology, are very rare. The anterior lateral line involves different neuromast patterning processes, specific distribution of synapses, and a unique role in behavior. Here, we report our observations regarding the development of the lateral line and analyze the physiological responses of the anterior lateral line to mechanical and water jet stimuli. Sensing in the fish head may be crucial to avoid obstacles, catch prey, and orient in water current, especially in the absence of visual cues. Alongside the lateral line, the trigeminal system, with its fine nerve endings innervating the skin, could contribute to perceiving mechanosensory stimulation. Therefore, we compare the physiological responses of the lateral line afferent neurons to responses of trigeminal neurons and responsiveness of auditory neurons. We show that anterior lateral line neurons are tuned to the velocity of mechanosensory ramp stimulation, while trigeminal neurons either only respond to mechanical step stimuli or fast ramp and step stimuli. Auditory neurons did not respond to mechanical or water jet stimuli. These results may prove to be essential in designing underwater robots and artificial lateral lines, with respect to the spectra of stimuli that the different mechanosensory systems in the larval head are tuned to, and underline the importance and functionality of the anterior lateral line system in the larval fish head.
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Affiliation(s)
- Nils Brehm
- Department of Developmental Biology, Institute for Biology 1, University of Freiburg, Freiburg, Germany
| | | | | | - Melanie Haehnel-Taguchi
- Department of Developmental Biology, Institute for Biology 1, University of Freiburg, Freiburg, Germany
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3
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Hodorovich DR, Lindsley PM, Berry AA, Burton DF, Marsden KC. Morphological and sensorimotor phenotypes in a zebrafish CHARGE syndrome model are domain-dependent. GENES, BRAIN, AND BEHAVIOR 2023; 22:e12839. [PMID: 36717082 PMCID: PMC10242184 DOI: 10.1111/gbb.12839] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/27/2022] [Revised: 12/22/2022] [Accepted: 01/20/2023] [Indexed: 02/01/2023]
Abstract
CHARGE syndrome is a heterogeneous disorder characterized by a spectrum of defects affecting multiple tissues and behavioral difficulties such as autism, attention-deficit/hyperactivity disorder, obsessive-compulsive disorder, anxiety, and sensory deficits. Most CHARGE cases arise from de novo, loss-of-function mutations in chromodomain-helicase-DNA-binding-protein-7 (CHD7). CHD7 is required for processes such as neuronal differentiation and neural crest cell migration, but how CHD7 affects neural circuit function to regulate behavior is unclear. To investigate the pathophysiology of behavioral symptoms in CHARGE, we established a mutant chd7 zebrafish line that recapitulates multiple CHARGE phenotypes including ear, cardiac, and craniofacial defects. Using a panel of behavioral assays, we found that chd7 mutants have specific auditory and visual behavior deficits that are independent of defects in sensory structures. Mauthner cell-dependent short-latency acoustic startle responses are normal in chd7 mutants, while Mauthner-independent long-latency responses are reduced. Responses to sudden decreases in light are also reduced in mutants, while responses to sudden increases in light are normal, suggesting that the retinal OFF pathway may be affected. Furthermore, by analyzing multiple chd7 alleles we observed that the penetrance of morphological and behavioral phenotypes is influenced by genetic background but that it also depends on the mutation location, with a chromodomain mutation causing the highest penetrance. This pattern is consistent with analysis of a CHARGE patient dataset in which symptom penetrance was highest in subjects with mutations in the CHD7 chromodomains. These results provide new insight into the heterogeneity of CHARGE and will inform future work to define CHD7-dependent neurobehavioral mechanisms.
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Affiliation(s)
- Dana R. Hodorovich
- Department of Biological SciencesNorth Carolina State UniversityRaleighNorth CarolinaUSA
| | - Patrick M. Lindsley
- Department of Biological SciencesNorth Carolina State UniversityRaleighNorth CarolinaUSA
- University of Virginia School of Medicine, University of VirginiaCharlottesvilleVAUSA
| | - Austen A. Berry
- Department of Biological SciencesNorth Carolina State UniversityRaleighNorth CarolinaUSA
- BiogenDurhamNCUSA
| | - Derek F. Burton
- Department of Biological SciencesNorth Carolina State UniversityRaleighNorth CarolinaUSA
- Washington UniversitySt. LouisMOUSA
| | - Kurt C. Marsden
- Department of Biological SciencesNorth Carolina State UniversityRaleighNorth CarolinaUSA
- Washington UniversitySt. LouisMOUSA
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4
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Coombs S. A multisensory perspective on near-field detection and localization of hydroacoustic sourcesa). THE JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA 2023; 153:2545. [PMID: 37130204 DOI: 10.1121/10.0017926] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/01/2023] [Accepted: 04/07/2023] [Indexed: 05/04/2023]
Abstract
This paper gives a brief synopsis of the research career of S.C. in fish bioacoustics with an emphasis on dipole near fields. The hydroacoustic nature of the dipole near field and the effective stimuli to lateral line and auditory systems combine to produce a multisensory, range-fractionated region that is critically important to many fish behaviors. The mottled sculpin and goldfish lateral lines encode the spatial complexities of the near field as spatial excitation patterns along the body surface to provide instantaneous snapshots of various source features such as distance, orientation, and direction of movement. In contrast, the pressure-sensitive channel of the goldfish auditory system [the anterior swim bladder (SB)-saccule complex] encodes the spatial complexities in a temporal fashion whenever the position or orientation of the source changes with respect to the anterior SB. A full appreciation for how these somatotopic and egocentric representations guide fish behavior requires an understanding of how multisensory information, including vision, is combined in sensorimotor regions of the brain to effect behavior. A brief overview of vertebrate brain organization indicates that behaviors directed to or away from hydroacoustic sources likely involve a variety of mechanisms, behavioral strategies, and brain regions.
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Affiliation(s)
- Sheryl Coombs
- Department of Biological Sciences, Bowling Green State University, Bowling Green, Ohio 43402, USA
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5
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Venuto A, Thibodeau-Beganny S, Trapani JG, Erickson T. A sensation for inflation: initial swim bladder inflation in larval zebrafish is mediated by the mechanosensory lateral line. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.01.12.523756. [PMID: 36712117 PMCID: PMC9882242 DOI: 10.1101/2023.01.12.523756] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
Larval zebrafish achieve neutral buoyancy by swimming up to the surface and taking in air through their mouths to inflate their swim bladders. We define this behavior as 'surfacing'. Little is known about the sensory basis for this underappreciated behavior of larval fish. A strong candidate is the mechanosensory lateral line, a hair cell-based sensory system that detects hydrodynamic information from sources like water currents, predators, prey, and surface waves. However, a role for the lateral line in mediating initial inflation of the swim bladder has not been reported. To explore the connection between the lateral line and surfacing, we utilized a genetic mutant (lhfpl5b-/-) that renders the zebrafish lateral line insensitive to mechanical stimuli. We observe that approximately half of these lateral line mutants over-inflate their swim bladders during initial inflation and become positively buoyant. Thus, we hypothesize that larval zebrafish use their lateral line to moderate interactions with the air-water interface during surfacing to regulate swim bladder inflation. To test the hypothesis that lateral line defects are responsible for swim bladder over-inflation, we show exogenous air is required for the hyperinflation phenotype and transgenic rescue of hair cell function restores normal inflation. We also find that chemical ablation of anterior lateral line hair cells in wild type larvae causes hyperinflation. Furthermore, we show that manipulation of lateral line sensory information results in abnormal inflation. Finally, we report spatial and temporal differences in the surfacing behavior between wild type and lateral line mutant larvae. In summary, we propose a novel sensory basis for achieving neutral buoyancy where larval zebrafish use their lateral line to sense the air-water interface and regulate initial swim bladder inflation.
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Affiliation(s)
- Alexandra Venuto
- Department of Biology, East Carolina University, Greenville, NC, USA
| | | | - Josef G. Trapani
- Department of Biology and Neuroscience Program, Amherst College, Amherst, MA, USA
| | - Timothy Erickson
- Department of Biology, University of New Brunswick, Fredericton, NB, Canada
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6
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Abstract
Motor circuits develop in sequence from those governing fast movements to those governing slow. Here we examine whether upstream sensory circuits are organized by similar principles. Using serial-section electron microscopy in larval zebrafish, we generated a complete map of the gravity-sensing (utricular) system spanning from the inner ear to the brainstem. We find that both sensory tuning and developmental sequence are organizing principles of vestibular topography. Patterned rostrocaudal innervation from hair cells to afferents creates an anatomically inferred directional tuning map in the utricular ganglion, forming segregated pathways for rostral and caudal tilt. Furthermore, the mediolateral axis of the ganglion is linked to both developmental sequence and neuronal temporal dynamics. Early-born pathways carrying phasic information preferentially excite fast escape circuits, whereas later-born pathways carrying tonic signals excite slower postural and oculomotor circuits. These results demonstrate that vestibular circuits are organized by tuning direction and dynamics, aligning them with downstream motor circuits and behaviors. How sensory systems are organized during development remains unclear. Here, the authors used electron microscopy to examine the gravity-sensing system in zebrafish, finding that directional tuning and developmental age are organizing principles of the transformation from vestibular sensation to motor control.
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7
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Restoring Shank3 in the rostral brainstem of shank3ab-/- zebrafish autism models rescues sensory deficits. Commun Biol 2021; 4:1411. [PMID: 34921227 PMCID: PMC8683502 DOI: 10.1038/s42003-021-02920-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2020] [Accepted: 11/24/2021] [Indexed: 11/22/2022] Open
Abstract
People with Phelan-McDermid Syndrome, caused by mutations in the SHANK3 gene, commonly exhibit reduced responses to sensory stimuli; yet the changes in brain-wide activity that link these symptoms to mutations in the shank3 gene remain unknown. Here we quantify movement in response to sudden darkness in larvae of two shank3 zebrafish mutant models and show that both models exhibit dampened responses to this stimulus. Using brain-wide activity mapping, we find that shank3−/− light-sensing brain regions show normal levels of activity while sensorimotor integration and motor regions are less active. Specifically restoring Shank3 function in a sensorimotor nucleus of the rostral brainstem enables the shank3−/− model to respond like wild-type. In sum, we find that reduced sensory responsiveness in shank3−/− models is associated with reduced activity in sensory processing brain regions and can be rescued by restoring Shank3 function in the rostral brainstem. These studies highlight the importance of Shank3 function in the rostral brainstem for integrating sensory inputs to generate behavioral adaptations to changing sensory stimuli. Robert Kozol et al. developed two zebrafish Shank3 models to characterize the basis of sensorimotor deficits, which are a consistent feature in SHANK3-deficient human patients (Phelan-McDermid Syndrome). Their results suggest that hindbrain regions require Shank3 for normal responses to light, and provide further insight toward the biology of sensory deficits in Shank3 mutants.
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8
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Plazas PV, Elgoyhen AB. The Cholinergic Lateral Line Efferent Synapse: Structural, Functional and Molecular Similarities With Those of the Cochlea. Front Cell Neurosci 2021; 15:765083. [PMID: 34712122 PMCID: PMC8545859 DOI: 10.3389/fncel.2021.765083] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2021] [Accepted: 09/21/2021] [Indexed: 11/25/2022] Open
Abstract
Vertebrate hair cell (HC) systems are innervated by efferent fibers that modulate their response to external stimuli. In mammals, the best studied efferent-HC synapse, the cholinergic medial olivocochlear (MOC) efferent system, makes direct synaptic contacts with HCs. The net effect of MOC activity is to hyperpolarize HCs through the activation of α9α10 nicotinic cholinergic receptors (nAChRs) and the subsequent activation of Ca2+-dependent SK2 potassium channels. A serious obstacle in research on many mammalian sensory systems in their native context is that their constituent neurons are difficult to access even in newborn animals, hampering circuit observation, mapping, or controlled manipulation. By contrast, fishes and amphibians have a superficial and accessible mechanosensory system, the lateral line (LL), which circumvents many of these problems. LL responsiveness is modulated by efferent neurons which aid to distinguish between external and self-generated stimuli. One component of the LL efferent system is cholinergic and its activation inhibits LL afferent activity, similar to what has been described for MOC efferents. The zebrafish (Danio rerio) has emerged as a powerful model system for studying human hearing and balance disorders, since LL HC are structurally and functionally analogous to cochlear HCs, but are optically and pharmacologically accessible within an intact specimen. Complementing mammalian studies, zebrafish have been used to gain significant insights into many facets of HC biology, including mechanotransduction and synaptic physiology as well as mechanisms of both hereditary and acquired HC dysfunction. With the rise of the zebrafish LL as a model in which to study auditory system function and disease, there has been an increased interest in studying its efferent system and evaluate the similarity between mammalian and piscine efferent synapses. Advances derived from studies in zebrafish include understanding the effect of the LL efferent system on HC and afferent activity, and revealing that an α9-containing nAChR, functionally coupled to SK channels, operates at the LL efferent synapse. In this review, we discuss the tools and findings of these recent investigations into zebrafish efferent-HC synapse, their commonalities with the mammalian counterpart and discuss several emerging areas for future studies.
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Affiliation(s)
- Paola V Plazas
- Instituto de Farmacología, Facultad de Medicina, Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Ana Belén Elgoyhen
- Instituto de Investigaciones en Ingeniería Genética y Biología Molecular, Consejo Nacional de Investigaciones Científicas y Técnicas, Buenos Aires, Argentina
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9
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Skandalis DA, Lunsford ET, Liao JC. Corollary discharge enables proprioception from lateral line sensory feedback. PLoS Biol 2021; 19:e3001420. [PMID: 34634044 PMCID: PMC8530527 DOI: 10.1371/journal.pbio.3001420] [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: 02/23/2021] [Revised: 10/21/2021] [Accepted: 09/21/2021] [Indexed: 11/26/2022] Open
Abstract
Animals modulate sensory processing in concert with motor actions. Parallel copies of motor signals, called corollary discharge (CD), prepare the nervous system to process the mixture of externally and self-generated (reafferent) feedback that arises during locomotion. Commonly, CD in the peripheral nervous system cancels reafference to protect sensors and the central nervous system from being fatigued and overwhelmed by self-generated feedback. However, cancellation also limits the feedback that contributes to an animal's awareness of its body position and motion within the environment, the sense of proprioception. We propose that, rather than cancellation, CD to the fish lateral line organ restructures reafference to maximize proprioceptive information content. Fishes' undulatory body motions induce reafferent feedback that can encode the body's instantaneous configuration with respect to fluid flows. We combined experimental and computational analyses of swimming biomechanics and hair cell physiology to develop a neuromechanical model of how fish can track peak body curvature, a key signature of axial undulatory locomotion. Without CD, this computation would be challenged by sensory adaptation, typified by decaying sensitivity and phase distortions with respect to an input stimulus. We find that CD interacts synergistically with sensor polarization to sharpen sensitivity along sensors' preferred axes. The sharpening of sensitivity regulates spiking to a narrow interval coinciding with peak reafferent stimulation, which prevents adaptation and homogenizes the otherwise variable sensor output. Our integrative model reveals a vital role of CD for ensuring precise proprioceptive feedback during undulatory locomotion, which we term external proprioception.
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Affiliation(s)
- Dimitri A. Skandalis
- Department of Biology & Whitney Laboratory for Marine Bioscience, University of Florida, St. Augustine, Florida, United States of America
- Department of Psychological & Brain Sciences, Johns Hopkins University, Baltimore, Maryland, United States of America
| | - Elias T. Lunsford
- Department of Biology & Whitney Laboratory for Marine Bioscience, University of Florida, St. Augustine, Florida, United States of America
| | - James C. Liao
- Department of Biology & Whitney Laboratory for Marine Bioscience, University of Florida, St. Augustine, Florida, United States of America
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10
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Hardy K, Amariutei AE, De Faveri F, Hendry A, Marcotti W, Ceriani F. Functional development and regeneration of hair cells in the zebrafish lateral line. J Physiol 2021; 599:3913-3936. [PMID: 34143497 PMCID: PMC7612129 DOI: 10.1113/jp281522] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2021] [Accepted: 06/03/2021] [Indexed: 12/22/2022] Open
Abstract
Hair cells are mechanosensory receptors responsible for transducing auditory and vestibular information into electrical signals, which are then transmitted with remarkable precision to afferent neurons. Different from mammals, the hair cells of lower vertebrates, including those present in the neuromasts of the zebrafish lateral line, regenerate following environmental or chemical insults. Here we investigate the time-course of regeneration of hair cells in vivo using electrophysiology, 2-photon imaging and immunostaining applied to wild-type and genetically-encoded fluorescent indicator zebrafish lines. Functional hair cells drive spontaneous action potentials in the posterior lateral line afferent fibres, the frequency of which progressively increases over the first 10-days post-fertilization (dpf). Higher firing-rate fibres are only observed from ~6 dpf. Following copper treatment, newly formed hair cells become functional and are able to drive APs in the afferent fibres within 48 hours in both early-larval (≤8 dpf) and late-larval (12-17 dpf) zebrafish. However, the complete functional regeneration of the entire neuromast is delayed in late-larval compared to early-larval zebrafish. We propose that while individual regenerating hair cells can rapidly become active, the acquisition of fully functional neuromasts progresses faster at early-larval stages, a time when hair cells are still under development. At both ages, the afferent terminals in the regenerating neuromast appear to make initial contact with supporting cells. The ablation of the lateral line afferent neurons prevents the timely regeneration of supporting cells and hair cells. These findings indicate that the afferent system is likely to facilitate or promote the neuromast regeneration process.
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Affiliation(s)
- Katherine Hardy
- Department of Biomedical Science, University of Sheffield, Sheffield, UK
| | - Ana E Amariutei
- Department of Biomedical Science, University of Sheffield, Sheffield, UK
| | | | - Aenea Hendry
- Department of Biomedical Science, University of Sheffield, Sheffield, UK
| | - Walter Marcotti
- Department of Biomedical Science, University of Sheffield, Sheffield, UK.,Sheffield Neuroscience Institute, University of Sheffield, Sheffield, UK
| | - Federico Ceriani
- Department of Biomedical Science, University of Sheffield, Sheffield, UK
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11
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Poulsen RE, Scholz LA, Constantin L, Favre-Bulle I, Vanwalleghem GC, Scott EK. Broad frequency sensitivity and complex neural coding in the larval zebrafish auditory system. Curr Biol 2021; 31:1977-1987.e4. [PMID: 33657408 PMCID: PMC8443405 DOI: 10.1016/j.cub.2021.01.103] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2020] [Revised: 12/16/2020] [Accepted: 01/28/2021] [Indexed: 02/02/2023]
Abstract
Most animals have complex auditory systems that identify salient features of the acoustic landscape to direct appropriate responses. In fish, these features include the volume, frequency, complexity, and temporal structure of acoustic stimuli transmitted through water. Larval fish have simple brains compared to adults but swim freely and depend on sophisticated sensory processing for survival.1-5 Zebrafish larvae, an important model for studying brain-wide neural networks, have thus far been found to possess a rudimentary auditory system, sensitive to a narrow range of frequencies and without evident sensitivity to acoustic features that are salient and ethologically important to adult fish.6,7 Here, we have combined a novel method for delivering water-borne sounds, a diverse assembly of acoustic stimuli, and whole-brain calcium imaging to describe the responses of individual auditory-responsive neurons across the brains of zebrafish larvae. Our results reveal responses to frequencies ranging from 100 Hz to 4 kHz, with evidence of frequency discrimination from 100 Hz to 2.5 kHz. Frequency-selective neurons are located in numerous regions of the brain, and neurons responsive to the same frequency are spatially grouped in some regions. Using functional clustering, we identified categories of neurons that are selective for a single pure-tone frequency, white noise, the sharp onset of acoustic stimuli, and stimuli involving a gradual crescendo. These results suggest a more nuanced auditory system than has previously been described in larval fish and provide insights into how a young animal's auditory system can both function acutely and serve as the scaffold for a more complex adult system.
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Affiliation(s)
- Rebecca E Poulsen
- Queensland Brain Institute, The University of Queensland, Brisbane, QLD 4072, Australia
| | - Leandro A Scholz
- Queensland Brain Institute, The University of Queensland, Brisbane, QLD 4072, Australia
| | - Lena Constantin
- Queensland Brain Institute, The University of Queensland, Brisbane, QLD 4072, Australia
| | - Itia Favre-Bulle
- Queensland Brain Institute, The University of Queensland, Brisbane, QLD 4072, Australia; School of Mathematics and Physics, The University of Queensland, Brisbane, QLD 4072, Australia
| | - Gilles C Vanwalleghem
- Queensland Brain Institute, The University of Queensland, Brisbane, QLD 4072, Australia.
| | - Ethan K Scott
- Queensland Brain Institute, The University of Queensland, Brisbane, QLD 4072, Australia.
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12
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Asgharsharghi A, Tian W, Haehnel-Taguchi M, López-Schier H. Sarm1 is dispensable for mechanosensory-motor transformations in zebrafish. MICROPUBLICATION BIOLOGY 2021; 2021. [PMID: 33688624 PMCID: PMC7930918 DOI: 10.17912/micropub.biology.000369] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Sarm1 is an evolutionary conserved protein that is essential for Wallerian axon degeneration. Sarm1 has emerged as a therapeutic target to treat neuropathies derived from metabolic or chemical stress and physical injury of axons. Yet, the full repertoire of consequences of inhibiting Sarm1 remains unknown. Here we show that loss of Sarm1 in zebrafish does not affect the sensorimotor transformations that underlie rheotaxis. In addition, Sarm1 deficit accelerates the re-growth of regenerating axons. These data indicate that systemic inhibition of Sarm1 is a viable therapeutic option compatible with sustained nervous system function.
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Affiliation(s)
| | - Weili Tian
- Helmholtz Zentrum Munich, Munich, Germany
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13
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Valera G, Markov DA, Bijari K, Randlett O, Asgharsharghi A, Baudoin JP, Ascoli GA, Portugues R, López-Schier H. A neuronal blueprint for directional mechanosensation in larval zebrafish. Curr Biol 2021; 31:1463-1475.e6. [PMID: 33545047 DOI: 10.1016/j.cub.2021.01.045] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2019] [Revised: 11/30/2020] [Accepted: 01/13/2021] [Indexed: 01/02/2023]
Abstract
Animals have a remarkable ability to use local cues to orient in space in the absence of a panoramic fixed reference frame. Here we use the mechanosensory lateral line in larval zebrafish to understand rheotaxis, an innate oriented swimming evoked by water currents. We generated a comprehensive light-microscopy cell-resolution projectome of lateralis afferent neurons (LANs) and used clustering techniques for morphological classification. We find surprising structural constancy among LANs. Laser-mediated microlesions indicate that precise topographic mapping of lateral-line receptors is not essential for rheotaxis. Recording neuronal-activity during controlled mechanical stimulation of neuromasts reveals unequal representation of water-flow direction in the hindbrain. We explored potential circuit architectures constrained by anatomical and functional data to suggest a parsimonious model under which the integration of lateralized signals transmitted by direction-selective LANs underlies the encoding of water-flow direction in the brain. These data provide a new framework to understand how animals use local mechanical cues to orient in space.
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Affiliation(s)
- Gema Valera
- Sensory Biology and Organogenesis, Helmholtz Zentrum Munich, Germany
| | | | - Kayvan Bijari
- Krasnow Institute for Advanced Study, George Mason University, VA, USA
| | - Owen Randlett
- Department of Molecular and Cellular Biology, Harvard University, MA, USA
| | | | | | - Giorgio A Ascoli
- Krasnow Institute for Advanced Study, George Mason University, VA, USA
| | | | - Hernán López-Schier
- Sensory Biology and Organogenesis, Helmholtz Zentrum Munich, Germany; Centre for Genomic Regulation, Barcelona, Spain.
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14
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Coombs S, Bak-Coleman J, Montgomery J. Rheotaxis revisited: a multi-behavioral and multisensory perspective on how fish orient to flow. J Exp Biol 2020; 223:223/23/jeb223008. [DOI: 10.1242/jeb.223008] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
ABSTRACT
Here, we review fish rheotaxis (orientation to flow) with the goal of placing it within a larger behavioral and multisensory context. Rheotaxis is a flexible behavior that is used by fish in a variety of circumstances: to search for upstream sources of current-borne odors, to intercept invertebrate drift and, in general, to conserve energy while preventing downstream displacement. Sensory information available for rheotaxis includes water-motion cues to the lateral line and body-motion cues to visual, vestibular or tactile senses when fish are swept downstream. Although rheotaxis can be mediated by a single sense, each sense has its own limitations. For example, lateral line cues are limited by the spatial characteristics of flow, visual cues by water visibility, and vestibular and other body-motion cues by the ability of fish to withstand downstream displacement. The ability of multiple senses to compensate for any single-sense limitation enables rheotaxis to persist over a wide range of sensory and flow conditions. Here, we propose a mechanism of rheotaxis that can be activated in parallel by one or more senses; a major component of this mechanism is directional selectivity of central neurons to broad patterns of water and/or body motions. A review of central mechanisms for vertebrate orienting behaviors and optomotor reflexes reveals several motorsensory integration sites in the CNS that could be involved in rheotaxis. As such, rheotaxis provides an excellent opportunity for understanding the multisensory control of a simple vertebrate behavior and how a simple motor act is integrated with others to form complex behaviors.
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Affiliation(s)
- Sheryl Coombs
- Bowling Green State University, Department of Biological Sciences and JP Scott Center for Neuroscience, Mind and Behavior, Bowling Green, OH 43403, USA
| | - Joe Bak-Coleman
- University of Washington, Center for an Informed Public and eScience Institute, Seattle, WA 98195, USA
| | - John Montgomery
- University of Auckland, School of Biological Sciences and Institute of Marine Science, Auckland 1142, New Zealand
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15
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Vanwalleghem G, Schuster K, Taylor MA, Favre-Bulle IA, Scott EK. Brain-Wide Mapping of Water Flow Perception in Zebrafish. J Neurosci 2020; 40:4130-4144. [PMID: 32277044 PMCID: PMC7244201 DOI: 10.1523/jneurosci.0049-20.2020] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2020] [Revised: 03/18/2020] [Accepted: 03/20/2020] [Indexed: 11/21/2022] Open
Abstract
Information about water flow, detected by lateral line organs, is critical to the behavior and survival of fish and amphibians. While certain aspects of water flow processing have been revealed through electrophysiology, we lack a comprehensive description of the neurons that respond to water flow and the network that they form. Here, we use brain-wide calcium imaging in combination with microfluidic stimulation to map out, at cellular resolution, neuronal responses involved in perceiving and processing water flow information in larval zebrafish. We find a diverse array of neurons responding to head-to-tail (h-t) flow, tail-to-head (t-h) flow, or both. Early in this pathway, in the lateral line ganglia, neurons respond almost exclusively to the simple presence of h-t or t-h flow, but later processing includes neurons responding specifically to flow onset, representing the accumulated displacement of flow during a stimulus, or encoding the speed of the flow. The neurons reporting on these more nuanced details are located across numerous brain regions, including some not previously implicated in water flow processing. A graph theory-based analysis of the brain-wide water flow network shows that a majority of this processing is dedicated to h-t flow detection, and this is reinforced by our finding that details like flow velocity and the total accumulated flow are only encoded for the h-t direction. The results represent the first brain-wide description of processing for this important modality, and provide a departure point for more detailed studies of the flow of information through this network.SIGNIFICANCE STATEMENT In aquatic animals, the lateral line is important for detecting water flow stimuli, but the brain networks that interpret this information remain mysterious. Here, we have imaged the activity of individual neurons across the entire brains of larval zebrafish, revealing all response types and their brain locations as water flow processing occurs. We find neurons that respond to the simple presence of water flow, and others attuned to the direction, speed, and duration of flow, or the accumulated displacement of water that has passed during the stimulus. With this information, we modeled the underlying network, describing a system that is nuanced in its processing of water flow simulating head-to-tail motion but rudimentary in processing flow in the tail-to-head direction.
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Affiliation(s)
- Gilles Vanwalleghem
- The Queensland Brain Institute, The University of Queensland, St. Lucia, Queensland 4072, Australia
| | - Kevin Schuster
- School of Biomedical Sciences, The University of Queensland, St. Lucia, Queensland 4072, Australia
| | - Michael A Taylor
- Australian Institute of Bioengineering and Nanotechnology, The University of Queensland, St. Lucia, Queensland 4072, Australia
| | - Itia A Favre-Bulle
- The Queensland Brain Institute, The University of Queensland, St. Lucia, Queensland 4072, Australia
- School of Mathematics and Physics, The University of Queensland, St. Lucia, Queensland 4072, Australia
| | - Ethan K Scott
- The Queensland Brain Institute, The University of Queensland, St. Lucia, Queensland 4072, Australia
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16
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Lunsford ET, Skandalis DA, Liao JC. Efferent modulation of spontaneous lateral line activity during and after zebrafish motor commands. J Neurophysiol 2019; 122:2438-2448. [PMID: 31642405 PMCID: PMC6966311 DOI: 10.1152/jn.00594.2019] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2019] [Revised: 10/18/2019] [Accepted: 10/18/2019] [Indexed: 01/27/2023] Open
Abstract
Accurate sensory processing during movement requires the animal to distinguish between external (exafferent) and self-generated (reafferent) stimuli to maintain sensitivity to biologically relevant cues. The lateral line system in fishes is a mechanosensory organ that experiences reafferent sensory feedback, via detection of fluid motion relative to the body generated during behaviors such as swimming. For the first time in larval zebrafish (Danio rerio), we employed simultaneous recordings of lateral line and motor activity to reveal the activity of afferent neurons arising from endogenous feedback from hindbrain efferent neurons during locomotion. Frequency of spontaneous spiking in posterior lateral line afferent neurons decreased during motor activity and was absent for more than half of swimming trials. Targeted photoablation of efferent neurons abolished the afferent inhibition that was correlated to swimming, indicating that inhibitory efferent neurons are necessary for modulating lateral line sensitivity during locomotion. We monitored calcium activity with Tg(elav13:GCaMP6s) fish and found synchronous activity between putative cholinergic efferent neurons and motor neurons. We examined correlates of motor activity to determine which may best predict the attenuation of afferent activity and therefore what components of the motor signal are translated through the corollary discharge. Swim duration was most strongly correlated to the change in afferent spike frequency. Attenuated spike frequency persisted past the end of the fictive swim bout, suggesting that corollary discharge also affects the glide phase of burst and glide locomotion. The duration of the glide in which spike frequency was attenuated increased with swim duration but decreased with motor frequency. Our results detail a neuromodulatory mechanism in larval zebrafish that adaptively filters self-generated flow stimuli during both the active and passive phases of locomotion.NEW & NOTEWORTHY For the first time in vivo, we quantify the endogenous effect of efferent activity on afferent gain control in a vertebrate hair cell system during and after locomotion. We believe that this pervasive effect has been underestimated when afferent activity of octavolateralis systems is characterized in the current literature. We further identify a refractory period out of phase with efferent control and place this gain mechanism in the context of gliding behavior of freely moving animals.
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Affiliation(s)
- Elias T Lunsford
- The Whitney Laboratory for Marine Bioscience, Department of Biology, University of Florida, Saint Augustine, Florida
| | - Dimitri A Skandalis
- The Whitney Laboratory for Marine Bioscience, Department of Biology, University of Florida, Saint Augustine, Florida
| | - James C Liao
- The Whitney Laboratory for Marine Bioscience, Department of Biology, University of Florida, Saint Augustine, Florida
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17
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Marquart GD, Tabor KM, Bergeron SA, Briggman KL, Burgess HA. Prepontine non-giant neurons drive flexible escape behavior in zebrafish. PLoS Biol 2019; 17:e3000480. [PMID: 31613896 PMCID: PMC6793939 DOI: 10.1371/journal.pbio.3000480] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2019] [Accepted: 09/10/2019] [Indexed: 11/18/2022] Open
Abstract
Many species execute ballistic escape reactions to avoid imminent danger. Despite fast reaction times, responses are often highly regulated, reflecting a trade-off between costly motor actions and perceived threat level. However, how sensory cues are integrated within premotor escape circuits remains poorly understood. Here, we show that in zebrafish, less precipitous threats elicit a delayed escape, characterized by flexible trajectories, which are driven by a cluster of 38 prepontine neurons that are completely separate from the fast escape pathway. Whereas neurons that initiate rapid escapes receive direct auditory input and drive motor neurons, input and output pathways for delayed escapes are indirect, facilitating integration of cross-modal sensory information. These results show that rapid decision-making in the escape system is enabled by parallel pathways for ballistic responses and flexible delayed actions and defines a neuronal substrate for hierarchical choice in the vertebrate nervous system.
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Affiliation(s)
- Gregory D. Marquart
- Division of Developmental Biology, Eunice Kennedy Shriver National Institute of Child Health and Human Development, Bethesda, Maryland, United States of America
- Neuroscience and Cognitive Science Program, University of Maryland, Maryland, United States of America
| | - Kathryn M. Tabor
- Division of Developmental Biology, Eunice Kennedy Shriver National Institute of Child Health and Human Development, Bethesda, Maryland, United States of America
| | - Sadie A. Bergeron
- Division of Developmental Biology, Eunice Kennedy Shriver National Institute of Child Health and Human Development, Bethesda, Maryland, United States of America
| | - Kevin L. Briggman
- Circuit Dynamics and Connectivity Unit, National Institute of Neurological Disorders and Stroke, Bethesda, Maryland, United States of America
| | - Harold A. Burgess
- Division of Developmental Biology, Eunice Kennedy Shriver National Institute of Child Health and Human Development, Bethesda, Maryland, United States of America
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18
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Kunst M, Laurell E, Mokayes N, Kramer A, Kubo F, Fernandes AM, Förster D, Dal Maschio M, Baier H. A Cellular-Resolution Atlas of the Larval Zebrafish Brain. Neuron 2019; 103:21-38.e5. [DOI: 10.1016/j.neuron.2019.04.034] [Citation(s) in RCA: 118] [Impact Index Per Article: 23.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2018] [Revised: 04/10/2019] [Accepted: 04/23/2019] [Indexed: 02/06/2023]
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19
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Pickett SB, Raible DW. Water Waves to Sound Waves: Using Zebrafish to Explore Hair Cell Biology. J Assoc Res Otolaryngol 2019; 20:1-19. [PMID: 30635804 DOI: 10.1007/s10162-018-00711-1] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2018] [Accepted: 12/19/2018] [Indexed: 01/09/2023] Open
Abstract
Although perhaps best known for their use in developmental studies, over the last couple of decades, zebrafish have become increasingly popular model organisms for investigating auditory system function and disease. Like mammals, zebrafish possess inner ear mechanosensory hair cells required for hearing, as well as superficial hair cells of the lateral line sensory system, which mediate detection of directional water flow. Complementing mammalian studies, zebrafish have been used to gain significant insights into many facets of hair cell biology, including mechanotransduction and synaptic physiology as well as mechanisms of both hereditary and acquired hair cell dysfunction. Here, we provide an overview of this literature, highlighting some of the particular advantages of using zebrafish to investigate hearing and hearing loss.
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Affiliation(s)
- Sarah B Pickett
- Department of Biological Structure, University of Washington, Health Sciences Building H-501, 1959 NE Pacific Street, Box 357420, Seattle, WA, 98195-7420, USA
- Graduate Program in Neuroscience, University of Washington, 1959 NE Pacific Street, Box 357270, Seattle, WA, 98195-7270, USA
| | - David W Raible
- Department of Biological Structure, University of Washington, Health Sciences Building H-501, 1959 NE Pacific Street, Box 357420, Seattle, WA, 98195-7420, USA.
- Graduate Program in Neuroscience, University of Washington, 1959 NE Pacific Street, Box 357270, Seattle, WA, 98195-7270, USA.
- Virginia Merrill Bloedel Hearing Research Center, University of Washington, 1701 NE Columbia Rd, Box 357923, Seattle, WA, 98195-7923, USA.
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20
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Haehnel-Taguchi M, Akanyeti O, Liao JC. Behavior, Electrophysiology, and Robotics Experiments to Study Lateral Line Sensing in Fishes. Integr Comp Biol 2018; 58:874-883. [PMID: 29982706 PMCID: PMC6204992 DOI: 10.1093/icb/icy066] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
The lateral line system is a sensory system unique to fishes and amphibians. It is composed of distributed mechanosensory hair cell organs on the head and body (neuromasts), which are sensitive to pressure gradients and water movements. Over the last decade, we have pursued an interdisciplinary approach by combining behavioral, electrophysiology, and robotics experiments to study this fascinating sensory system. In behavioral and electrophysiology experiments, we have studied the larval lateral line system in the model genetic organism, zebrafish (Danio rerio). We found that the lateral line system, even in 5-day-old larvae, is involved in an array of behaviors that are critical to survival, and the deflection of a single neuromast can elicit a swimming response. In robotics experiments, we used a range of physical models with distributed pressure sensors to better understand the hydrodynamic environments from the local perspective of a fish or robot. So far, our efforts have focused on extracting control-related information for a range of application scenarios including characterizing unsteady flows such as Kármán vortex streets for station holding. We also used robot models to test biological hypotheses on how morphology and movement of fishes affect lateral line sensing. Overall, with this review we aim to increase the visibility and accessibility of this multi-disciplinary research approach.
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Affiliation(s)
- Melanie Haehnel-Taguchi
- Faculty of Biology, Albert-Ludwigs Universität Freiburg, Hauptstraße 1, Freiburg D-79104, Germany
| | - Otar Akanyeti
- Department of Computer Science, Aberystwyth University, Penglais Campus, Aberystwyth SY23 3FL, UK
| | - James C Liao
- The Whitney Laboratory for Marine Bioscience, Department of Biology, University of Florida, St. Augustine, FL 32080, USA
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21
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Li C, Wang X, Wu J, Zhang X, Fan C, Guo H, Song J. Heterogeneity of neuromasts in a fish without lateral line canals: the pufferfish ( Takifugu obscurus) model. ACTA ACUST UNITED AC 2018; 221:jeb.186163. [PMID: 29997160 DOI: 10.1242/jeb.186163] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2018] [Accepted: 07/04/2018] [Indexed: 11/20/2022]
Abstract
Fish detect water motion with their mechanosensory lateral line. The basic functional unit of the lateral line is the neuromast. In most fish species, neuromasts are located in lateral line canals (canal neuromasts) or on the skin (superficial neuromasts). In this paper, we describe the lateral line system of the pufferfish, Takifugu obscurus If threatened, this fish inflates its body by sucking water into the esophagus. Pufferfish lack a canal system but have neuromasts located directly on the skin or in open grooves. Each groove houses tall, medium and short neuromasts, based on the height of their pedestal. One or more medium neuromasts were always located between two tall neuromasts, and the short neuromasts were scattered between them. Tall neuromasts showed phasic responses to water jets, similar to the canal neuromasts of other fish species. In contrast, the medium and short neuromasts showed tonic responses to water jets. The response properties of nerve fibers that innervated the medium and short neuromasts were similar to those of the superficial neuromasts found in other fish species. Our results suggest that each groove of a pufferfish has two functional groups of neuromasts. This may allow pufferfish to extract spatial and temporal hydrodynamic information, despite the changes in body shape that occur during and after inflation. The short neuromasts at the bottom of a groove most likely supplement the medium neuromasts when the body is maximally inflated.
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Affiliation(s)
- Chao Li
- Institute for Marine Biosystem and Neuroscience, Shanghai Ocean University, Shanghai 201306, China.,National Demonstration Center for Experimental Fisheries Science Education (Shanghai Ocean University), Shanghai 201306, China.,International Research Center for Marine Biosciences at Shanghai Ocean University, Ministry of Science and Technology, Shanghai 201306, China
| | - Xiaojie Wang
- Institute for Marine Biosystem and Neuroscience, Shanghai Ocean University, Shanghai 201306, China.,National Demonstration Center for Experimental Fisheries Science Education (Shanghai Ocean University), Shanghai 201306, China.,International Research Center for Marine Biosciences at Shanghai Ocean University, Ministry of Science and Technology, Shanghai 201306, China
| | - Jianyong Wu
- Department of Neuroscience, Georgetown University, Washington, DC 20007, USA
| | - Xuguang Zhang
- Institute for Marine Biosystem and Neuroscience, Shanghai Ocean University, Shanghai 201306, China.,National Demonstration Center for Experimental Fisheries Science Education (Shanghai Ocean University), Shanghai 201306, China.,International Research Center for Marine Biosciences at Shanghai Ocean University, Ministry of Science and Technology, Shanghai 201306, China
| | - Chunxin Fan
- Institute for Marine Biosystem and Neuroscience, Shanghai Ocean University, Shanghai 201306, China.,National Demonstration Center for Experimental Fisheries Science Education (Shanghai Ocean University), Shanghai 201306, China.,International Research Center for Marine Biosciences at Shanghai Ocean University, Ministry of Science and Technology, Shanghai 201306, China
| | - Hongyi Guo
- Institute for Marine Biosystem and Neuroscience, Shanghai Ocean University, Shanghai 201306, China.,National Demonstration Center for Experimental Fisheries Science Education (Shanghai Ocean University), Shanghai 201306, China.,International Research Center for Marine Biosciences at Shanghai Ocean University, Ministry of Science and Technology, Shanghai 201306, China
| | - Jiakun Song
- Institute for Marine Biosystem and Neuroscience, Shanghai Ocean University, Shanghai 201306, China .,National Demonstration Center for Experimental Fisheries Science Education (Shanghai Ocean University), Shanghai 201306, China.,International Research Center for Marine Biosciences at Shanghai Ocean University, Ministry of Science and Technology, Shanghai 201306, China
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22
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Vanwalleghem G, Heap LA, Scott EK. A profile of auditory-responsive neurons in the larval zebrafish brain. J Comp Neurol 2017; 525:3031-3043. [DOI: 10.1002/cne.24258] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2017] [Revised: 05/26/2017] [Accepted: 05/29/2017] [Indexed: 12/19/2022]
Affiliation(s)
- Gilles Vanwalleghem
- School of Biomedical Sciences; The University of Queensland; St Lucia QLD Australia
| | - Lucy A. Heap
- School of Biomedical Sciences; The University of Queensland; St Lucia QLD Australia
| | - Ethan K. Scott
- School of Biomedical Sciences; The University of Queensland; St Lucia QLD Australia
- The Queensland Brain Institute, The University of Queensland; St Lucia QLD Australia
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23
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Troconis EL, Ordoobadi AJ, Sommers TF, Aziz‐Bose R, Carter AR, Trapani JG. Intensity-dependent timing and precision of startle response latency in larval zebrafish. J Physiol 2017; 595:265-282. [PMID: 27228964 PMCID: PMC5199724 DOI: 10.1113/jp272466] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2016] [Accepted: 05/17/2016] [Indexed: 01/12/2023] Open
Abstract
KEY POINTS Using high-speed videos time-locked with whole-animal electrical recordings, simultaneous measurement of behavioural kinematics and field potential parameters of C-start startle responses allowed for discrimination between short-latency and long-latency C-starts (SLCs vs. LLCs) in larval zebrafish. Apart from their latencies, SLC kinematics and SLC field potential parameters were intensity independent. Increasing stimulus intensity increased the probability of evoking an SLC and decreased mean SLC latencies while increasing their precision; subtraction of field potential latencies from SLC latencies revealed a fixed time delay between the two measurements that was intensity independent. The latency and the precision in the latency of the SLC field potentials were linearly correlated to the latencies and precision of the first evoked action potentials (spikes) in hair-cell afferent neurons of the lateral line. Together, these findings indicate that first spike latency (FSL) is a fast encoding mechanism that can serve to precisely initiate startle responses when speed is critical for survival. ABSTRACT Vertebrates rely on fast sensory encoding for rapid and precise initiation of startle responses. In afferent sensory neurons, trains of action potentials (spikes) encode stimulus intensity within the onset time of the first evoked spike (first spike latency; FSL) and the number of evoked spikes. For speed of initiation of startle responses, FSL would be the more advantageous mechanism to encode the intensity of a threat. However, the intensity dependence of FSL and spike number and whether either determines the precision of startle response initiation is not known. Here, we examined short-latency startle responses (SLCs) in larval zebrafish and tested the hypothesis that first spike latencies and their precision (jitter) determine the onset time and precision of SLCs. We evoked startle responses via activation of Channelrhodopsin (ChR2) expressed in ear and lateral line hair cells and acquired high-speed videos of head-fixed larvae while simultaneously recording underlying field potentials. This method allowed for discrimination between primary SLCs and less frequent, long-latency startle responses (LLCs). Quantification of SLC kinematics and field potential parameters revealed that, apart from their latencies, they were intensity independent. We found that increasing stimulus intensity decreased SLC latencies while increasing their precision, which was significantly correlated with corresponding changes in field potential latencies and their precision. Single afferent neuron recordings from the lateral line revealed a similar intensity-dependent decrease in first spike latencies and their jitter, which could account for the intensity-dependent changes in timing and precision of startle response latencies.
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Affiliation(s)
| | | | | | | | - Ashley R. Carter
- Department of Physics and AstronomyAmherst CollegeAmherstMA01002USA
| | - Josef G. Trapani
- Department of BiologyAmherst CollegeAmherstMA01002USA
- Neuroscience ProgramAmherst CollegeAmherstMA01002USA
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24
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Olt J, Allen CE, Marcotti W. In vivo physiological recording from the lateral line of juvenile zebrafish. J Physiol 2016; 594:5427-38. [PMID: 27161862 PMCID: PMC5043028 DOI: 10.1113/jp271794] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2015] [Accepted: 05/04/2016] [Indexed: 01/08/2023] Open
Abstract
KEY POINTS Zebrafish provide a unique opportunity to investigate in vivo sensory transduction in mature hair cells. We have developed a method for studying the biophysical properties of mature hair cells from the lateral line of juvenile zebrafish. The method involves application of the anaesthetic benzocaine and intubation to maintain ventilation and oxygenation through the gills. The same approach could be used for in vivo functional studies in other sensory and non-sensory systems from juvenile and adult zebrafish. ABSTRACT Hair cells are sensory receptors responsible for transducing auditory and vestibular information into electrical signals, which are then transmitted with remarkable precision to afferent neurons. The zebrafish lateral line is emerging as an excellent in vivo model for genetic and physiological analysis of hair cells and neurons. However, research has been limited to larval stages because zebrafish become protected from the time of independent feeding under European law (from 5.2 days post-fertilization (dpf) at 28.5°C). In larval zebrafish, the functional properties of most of hair cells, as well as those of other excitable cells, are still immature. We have developed an experimental protocol to record electrophysiological properties from hair cells of the lateral line in juvenile zebrafish. We found that the anaesthetic benzocaine at 50 mg l(-1) was an effective and safe anaesthetic to use on juvenile zebrafish. Concentrations up to 300 mg l(-1) did not affect the electrical properties or synaptic vesicle release of juvenile hair cells, unlike the commonly used anaesthetic MS-222, which reduces the size of basolateral membrane K(+) currents. Additionally, we implemented a method to maintain gill movement, and as such respiration and blood oxygenation, via the intubation of > 21 dpf zebrafish. The combination of benzocaine and intubation provides an experimental platform to investigate the physiology of mature hair cells from live zebrafish. More generally, this method would allow functional studies involving live imaging and electrophysiology from juvenile and adult zebrafish.
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Affiliation(s)
- Jennifer Olt
- Department of Biomedical Science, University of Sheffield, Sheffield, S10 2TN, UK
| | - Claire E Allen
- Department of Biomedical Science, University of Sheffield, Sheffield, S10 2TN, UK
| | - Walter Marcotti
- Department of Biomedical Science, University of Sheffield, Sheffield, S10 2TN, UK.
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25
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Olt J, Ordoobadi AJ, Marcotti W, Trapani JG. Physiological recordings from the zebrafish lateral line. Methods Cell Biol 2016; 133:253-79. [PMID: 27263416 DOI: 10.1016/bs.mcb.2016.02.004] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
During sensory transduction, external physical stimuli are translated into an internal biological signal. In vertebrates, hair cells are specialized mechanosensory receptors that transduce sound, gravitational forces, and head movements into electrical signals that are transmitted with remarkable precision and efficiency to afferent neurons. Hair cells have a conserved structure between species and are also found in the lateral line system of fish, including zebrafish, which serve as an ideal animal model to study sensory transmission in vivo. In this chapter, we describe the methods required to investigate the biophysical properties underlying mechanosensation in the lateral line of the zebrafish in vivo from microphonic potentials and single hair cell patch-clamp recordings to single afferent neuron recordings. These techniques provide real-time measurements of hair-cell transduction and transmission following delivery of controlled and defined stimuli and their combined use on the intact zebrafish provides a powerful platform to investigate sensory encoding in vivo.
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Affiliation(s)
- J Olt
- University of Sheffield, Sheffield, United Kingdom
| | | | - W Marcotti
- University of Sheffield, Sheffield, United Kingdom
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26
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27
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Levi R, Akanyeti O, Ballo A, Liao JC. Frequency response properties of primary afferent neurons in the posterior lateral line system of larval zebrafish. J Neurophysiol 2014; 113:657-68. [PMID: 25355959 DOI: 10.1152/jn.00414.2014] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
The ability of fishes to detect water flow with the neuromasts of their lateral line system depends on the physiology of afferent neurons as well as the hydrodynamic environment. Using larval zebrafish (Danio rerio), we measured the basic response properties of primary afferent neurons to mechanical deflections of individual superficial neuromasts. We used two types of stimulation protocols. First, we used sine wave stimulation to characterize the response properties of the afferent neurons. The average frequency-response curve was flat across stimulation frequencies between 0 and 100 Hz, matching the filtering properties of a displacement detector. Spike rate increased asymptotically with frequency, and phase locking was maximal between 10 and 60 Hz. Second, we used pulse train stimulation to analyze the maximum spike rate capabilities. We found that afferent neurons could generate up to 80 spikes/s and could follow a pulse train stimulation rate of up to 40 pulses/s in a reliable and precise manner. Both sine wave and pulse stimulation protocols indicate that an afferent neuron can maintain their evoked activity for longer durations at low stimulation frequencies than at high frequencies. We found one type of afferent neuron based on spontaneous activity patterns and discovered a correlation between the level of spontaneous and evoked activity. Overall, our results establish the baseline response properties of lateral line primary afferent neurons in larval zebrafish, which is a crucial step in understanding how vertebrate mechanoreceptive systems sense and subsequently process information from the environment.
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Affiliation(s)
- Rafael Levi
- The Whitney Laboratory for Marine Bioscience, Department of Biology, University of Florida, St. Augustine, Florida
| | - Otar Akanyeti
- The Whitney Laboratory for Marine Bioscience, Department of Biology, University of Florida, St. Augustine, Florida
| | - Aleksander Ballo
- The Whitney Laboratory for Marine Bioscience, Department of Biology, University of Florida, St. Augustine, Florida
| | - James C Liao
- The Whitney Laboratory for Marine Bioscience, Department of Biology, University of Florida, St. Augustine, Florida
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28
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Haehnel-Taguchi M, Akanyeti O, Liao JC. Afferent and motoneuron activity in response to single neuromast stimulation in the posterior lateral line of larval zebrafish. J Neurophysiol 2014; 112:1329-39. [PMID: 24966296 DOI: 10.1152/jn.00274.2014] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The lateral line system of fishes contains mechanosensory receptors along the body surface called neuromasts, which can detect water motion relative to the body. The ability to sense flow informs many behaviors, such as schooling, predator avoidance, and rheotaxis. Here, we developed a new approach to stimulate individual neuromasts while either recording primary sensory afferent neuron activity or swimming motoneuron activity in larval zebrafish (Danio rerio). Our results allowed us to characterize the transfer functions between a controlled lateral line stimulus, its representation by primary sensory neurons, and its subsequent behavioral output. When we deflected the cupula of a neuromast with a ramp command, we found that the connected afferent neuron exhibited an adapting response which was proportional in strength to deflection velocity. The maximum spike rate of afferent neurons increased sigmoidally with deflection velocity, with a linear range between 0.1 and 1.0 μm/ms. However, spike rate did not change when the cupula was deflected below 8 μm, regardless of deflection velocity. Our findings also reveal an unexpected sensitivity in the larval lateral line system: stimulation of a single neuromast could elicit a swimming response which increased in reliability with increasing deflection velocities. At high deflection velocities, we observed that lateral line evoked swimming has intermediate values of burst frequency and duty cycle that fall between electrically evoked and spontaneous swimming. An understanding of the sensory capabilities of a single neuromast will help to build a better picture of how stimuli are encoded at the systems level and ultimately translated into behavior.
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Affiliation(s)
- Melanie Haehnel-Taguchi
- The Whitney Laboratory for Marine Bioscience, Department of Biology, University of Florida, Saint Augustine, Florida
| | - Otar Akanyeti
- The Whitney Laboratory for Marine Bioscience, Department of Biology, University of Florida, Saint Augustine, Florida
| | - James C Liao
- The Whitney Laboratory for Marine Bioscience, Department of Biology, University of Florida, Saint Augustine, Florida
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29
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Monesson-Olson BD, Browning-Kamins J, Aziz-Bose R, Kreines F, Trapani JG. Optical stimulation of zebrafish hair cells expressing channelrhodopsin-2. PLoS One 2014; 9:e96641. [PMID: 24791934 PMCID: PMC4008597 DOI: 10.1371/journal.pone.0096641] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2014] [Accepted: 04/09/2014] [Indexed: 11/19/2022] Open
Abstract
Vertebrate hair cells are responsible for the high fidelity encoding of mechanical stimuli into trains of action potentials (spikes) in afferent neurons. Here, we generated a transgenic zebrafish line expressing Channelrhodopsin-2 (ChR2) under the control of the hair-cell specific myo6b promoter, in order to examine the role of the mechanoelectrical transduction (MET) channel in sensory encoding in afferent neurons. We performed in vivo recordings from afferent neurons of the zebrafish lateral line while activating hair cells with either mechanical stimuli from a waterjet or optical stimuli from flashes of ∼470-nm light. Comparison of the patterns of encoded spikes during 100-ms stimuli revealed no difference in mean first spike latency between the two modes of activation. However, there was a significant increase in the variability of first spike latency during optical stimulation as well as an increase in the mean number of spikes per stimulus. Next, we compared encoding of spikes during hair-cell stimulation at 10, 20, and 40-Hz. Consistent with the increased variability of first spike latency, we saw a significant decrease in the vector strength of phase-locked spiking during optical stimulation. These in vivo results support a physiological role for the MET channel in the high fidelity of first spike latency seen during encoding of mechanical sensory stimuli. Finally, we examined whether remote activation of hair cells via ChR2 activation was sufficient to elicit escape responses in free-swimming larvae. In transgenic larvae, 100-ms flashes of ∼470-nm light resulted in escape responses that occurred concomitantly with field recordings indicating Mauthner cell activity. Altogether, the myo6b:ChR2 transgenic line provides a platform to investigate hair-cell function and sensory encoding, hair-cell sensory input to the Mauthner cell, and the ability to remotely evoke behavior in free-swimming zebrafish.
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Affiliation(s)
| | - Jenna Browning-Kamins
- Neuroscience Program, Amherst College, Amherst, Massachusetts, United States of America
| | - Razina Aziz-Bose
- Neuroscience Program, Amherst College, Amherst, Massachusetts, United States of America
| | - Fabiana Kreines
- Neuroscience Program, Amherst College, Amherst, Massachusetts, United States of America
| | - Josef G. Trapani
- Department of Biology, Amherst College, Amherst, Massachusetts, United States of America
- Neuroscience Program, Amherst College, Amherst, Massachusetts, United States of America
- * E-mail:
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30
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Olt J, Johnson SL, Marcotti W. In vivo and in vitro biophysical properties of hair cells from the lateral line and inner ear of developing and adult zebrafish. J Physiol 2014; 592:2041-58. [PMID: 24566541 PMCID: PMC4027864 DOI: 10.1113/jphysiol.2013.265108] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
Hair cells detect and process sound and movement information, and transmit this with remarkable precision and efficiency to afferent neurons via specialized ribbon synapses. The zebrafish is emerging as a powerful model for genetic analysis of hair cell development and function both in vitro and in vivo. However, the full exploitation of the zebrafish is currently limited by the difficulty in obtaining systematic electrophysiological recordings from hair cells under physiological recording conditions. Thus, the biophysical properties of developing and adult zebrafish hair cells are largely unknown. We investigated potassium and calcium currents, voltage responses and synaptic activity in hair cells from the lateral line and inner ear in vivo and using near-physiological in vitro recordings. We found that the basolateral current profile of hair cells from the lateral line becomes more segregated with age, and that cells positioned in the centre of the neuromast show more mature characteristics and those towards the edge retain a more immature phenotype. The proportion of mature-like hair cells within a given neuromast increased with zebrafish development. Hair cells from the inner ear showed a developmental change in current profile between the juvenile and adult stages. In lateral line hair cells from juvenile zebrafish, exocytosis also became more efficient and required less calcium for vesicle fusion. In hair cells from mature zebrafish, the biophysical characteristics of ion channels and exocytosis resembled those of hair cells from other lower vertebrates and, to some extent, those in the immature mammalian vestibular and auditory systems. We show that although the zebrafish provides a suitable animal model for studies on hair cell physiology, it is advisable to consider that the age at which the majority of hair cells acquire a mature-type configuration is reached only in the juvenile lateral line and in the inner ear from >2 months after hatching.
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Affiliation(s)
- Jennifer Olt
- Department of Biomedical Science, University of Sheffield, Sheffield, UK
| | - Stuart L Johnson
- Department of Biomedical Science, University of Sheffield, Sheffield, UK
| | - Walter Marcotti
- Department of Biomedical Science, University of Sheffield, Sheffield, UK
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31
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Pujol-Martí J, López-Schier H. Developmental and architectural principles of the lateral-line neural map. Front Neural Circuits 2013; 7:47. [PMID: 23532704 PMCID: PMC3607791 DOI: 10.3389/fncir.2013.00047] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2013] [Accepted: 03/06/2013] [Indexed: 11/13/2022] Open
Abstract
The transmission and central representation of sensory cues through the accurate construction of neural maps is essential for animals to react to environmental stimuli. Structural diversity of sensorineural maps along a continuum between discrete- and continuous-map architectures can influence behavior. The mechanosensory lateral line of fishes and amphibians, for example, detects complex hydrodynamics occurring around the animal body. It triggers innate fast escape reactions but also modulates complex navigation behaviors that require constant knowledge about the environment. The aim of this article is to summarize recent work in the zebrafish that has shed light on the development and structure of the lateralis neural map, which is helping to understand how individual sensory modalities generate appropriate behavioral responses to the sensory context.
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Affiliation(s)
- Jesús Pujol-Martí
- Research Unit of Sensory Biology and Organogenesis, Helmholtz Zentrum München Neuherberg, Munich, Germany
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32
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Palanca AMS, Sagasti A. Optogenetic activation of zebrafish somatosensory neurons using ChEF-tdTomato. J Vis Exp 2013:e50184. [PMID: 23407374 DOI: 10.3791/50184] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Larval zebrafish are emerging as a model for describing the development and function of simple neural circuits. Due to their external fertilization, rapid development, and translucency, zebrafish are particularly well suited for optogenetic approaches to investigate neural circuit function. In this approach, light-sensitive ion channels are expressed in specific neurons, enabling the experimenter to activate or inhibit them at will and thus assess their contribution to specific behaviors. Applying these methods in larval zebrafish is conceptually simple but requires the optimization of technical details. Here we demonstrate a procedure for expressing a channelrhodopsin variant in larval zebrafish somatosensory neurons, photo-activating single cells, and recording the resulting behaviors. By introducing a few modifications to previously established methods, this approach could be used to elicit behavioral responses from single neurons activated up to at least 4 days post-fertilization (dpf). Specifically, we created a transgene using a somatosensory neuron enhancer, CREST3, to drive the expression of the tagged channelrhodopsin variant, ChEF-tdTomato. Injecting this transgene into 1-cell stage embryos results in mosaic expression in somatosensory neurons, which can be imaged with confocal microscopy. Illuminating identified cells in these animals with light from a 473 nm DPSS laser, guided through a fiber optic cable, elicits behaviors that can be recorded with a high-speed video camera and analyzed quantitatively. This technique could be adapted to study behaviors elicited by activating any zebrafish neuron. Combining this approach with genetic or pharmacological perturbations will be a powerful way to investigate circuit formation and function.
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Affiliation(s)
- Ana Marie S Palanca
- Department of Molecular, Cell, and Developmental Biology, University of California, Los Angeles, USA
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33
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Information Encoding and Processing by the Peripheral Lateral Line System. SPRINGER HANDBOOK OF AUDITORY RESEARCH 2013. [DOI: 10.1007/2506_2013_15] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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A gradient in endogenous rhythmicity and oscillatory drive matches recruitment order in an axial motor pool. J Neurosci 2012; 32:10925-39. [PMID: 22875927 DOI: 10.1523/jneurosci.1809-12.2012] [Citation(s) in RCA: 72] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
The rhythmic firing behavior of spinal motoneurons is a function of their electrical properties and synaptic inputs. However, the relative contribution of endogenous versus network-based rhythmogenic mechanisms to locomotion is unclear. To address this issue, we have recorded from identified motoneurons and compared their current-evoked firing patterns to network-driven ones in the larval zebrafish (Danio rerio). Zebrafish axial motoneurons are recruited topographically from the bottom of the spinal cord up. Here, we have explored differences in the morphology of axial motoneurons, their electrical properties, and their synaptic drive, to reveal how they match the topographic pattern of recruitment. More ventrally located "secondary" motoneurons generate bursts of action potentials in response to constant current steps, demonstrating a strong inherent rhythmogenesis. The membrane potential oscillations underlying bursting behavior occur in the normal frequency range of swimming. In contrast, more dorsal secondaries chatter in response to current, while the most dorsally distributed "primary" motoneurons all fire tonically. We find that systematic variations in excitability and endogenous rhythmicity are inversely related to the level of oscillatory synaptic drive within the entire axial motor pool. Specifically, bursting cells exhibit the least amount of drive, while tonic cells exhibit the most. Our data suggest that increases in swimming frequency are accomplished by the recruitment of axial motoneurons that progressively rely on instructive synaptic drive to shape their oscillatory activity appropriately. Thus, within the zebrafish spinal cord, there are differences in the relative contribution of endogenous versus network-based rhythms to locomotion and these vary predictably according to order of recruitment.
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