1
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Baier H, Scott EK. The Visual Systems of Zebrafish. Annu Rev Neurosci 2024; 47:255-276. [PMID: 38663429 DOI: 10.1146/annurev-neuro-111020-104854] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/09/2024]
Abstract
The zebrafish visual system has become a paradigmatic preparation for behavioral and systems neuroscience. Around 40 types of retinal ganglion cells (RGCs) serve as matched filters for stimulus features, including light, optic flow, prey, and objects on a collision course. RGCs distribute their signals via axon collaterals to 12 retinorecipient areas in forebrain and midbrain. The major visuomotor hub, the optic tectum, harbors nine RGC input layers that combine information on multiple features. The retinotopic map in the tectum is locally adapted to visual scene statistics and visual subfield-specific behavioral demands. Tectal projections to premotor centers are topographically organized according to behavioral commands. The known connectivity in more than 20 processing streams allows us to dissect the cellular basis of elementary perceptual and cognitive functions. Visually evoked responses, such as prey capture or loom avoidance, are controlled by dedicated multistation pathways that-at least in the larva-resemble labeled lines. This architecture serves the neuronal code's purpose of driving adaptive behavior.
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Affiliation(s)
- Herwig Baier
- Department of Genes-Circuits-Behavior, Max Planck Institute for Biological Intelligence, Martinsried, Germany;
| | - Ethan K Scott
- Department of Anatomy and Physiology, School of Biomedical Sciences, The University of Melbourne, Parkville, Victoria, Australia
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2
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Beaulieu MO, Thomas ED, Raible DW. Transdifferentiation is temporally uncoupled from progenitor pool expansion during hair cell regeneration in the zebrafish inner ear. Development 2024; 151:dev202944. [PMID: 39045613 DOI: 10.1242/dev.202944] [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: 04/09/2024] [Accepted: 07/15/2024] [Indexed: 07/25/2024]
Abstract
Death of mechanosensory hair cells in the inner ear is a common cause of auditory and vestibular impairment in mammals, which have a limited ability to regrow these cells after damage. In contrast, non-mammalian vertebrates, including zebrafish, can robustly regenerate hair cells after severe organ damage. The zebrafish inner ear provides an understudied model system for understanding hair cell regeneration in organs that are highly conserved with their mammalian counterparts. Here, we quantitatively examine hair cell addition during growth and regeneration of the larval zebrafish inner ear. We used a genetically encoded ablation method to induce hair cell death and we observed gradual regeneration with correct spatial patterning over a 2-week period following ablation. Supporting cells, which surround and are a source of new hair cells, divide in response to hair cell ablation, expanding the possible progenitor pool. In parallel, nascent hair cells arise from direct transdifferentiation of progenitor pool cells temporally uncoupled from supporting cell division. These findings reveal a previously unrecognized mechanism of hair cell regeneration with implications for how hair cells may be encouraged to regenerate in the mammalian ear.
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Affiliation(s)
- Marielle O Beaulieu
- Molecular and Cellular Biology Graduate Program, University of Washington, Seattle, WA 98195, USA
- Virginia Merrill Bloedel Hearing Research Center, Department of Otolaryngology - Head and Neck Surgery, University of Washington, Seattle, WA 98195, USA
| | - Eric D Thomas
- Neuroscience Graduate Program, University of Washington, Seattle, WA 98195, USA
- Department of Biological Structure, University of Washington, Seattle, WA 98195, USA
| | - David W Raible
- Molecular and Cellular Biology Graduate Program, University of Washington, Seattle, WA 98195, USA
- Virginia Merrill Bloedel Hearing Research Center, Department of Otolaryngology - Head and Neck Surgery, University of Washington, Seattle, WA 98195, USA
- Neuroscience Graduate Program, University of Washington, Seattle, WA 98195, USA
- Department of Biological Structure, University of Washington, Seattle, WA 98195, USA
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3
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Beaulieu MO, Thomas ED, Raible DW. Transdifferentiation is uncoupled from progenitor pool expansion during hair cell regeneration in the zebrafish inner ear. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.04.09.588777. [PMID: 38645220 PMCID: PMC11030336 DOI: 10.1101/2024.04.09.588777] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/23/2024]
Abstract
Death of mechanosensory hair cells in the inner ear is a common cause of auditory and vestibular impairment in mammals, which have a limited ability to regrow these cells after damage. In contrast, non-mammalian vertebrates including zebrafish can robustly regenerate hair cells following severe organ damage. The zebrafish inner ear provides an understudied model system for understanding hair cell regeneration in organs that are highly conserved with their mammalian counterparts. Here we quantitatively examine hair cell addition during growth and regeneration of the larval zebrafish inner ear. We used a genetically encoded ablation method to induce hair cell death and observed gradual regeneration with correct spatial patterning over two weeks following ablation. Supporting cells, which surround and are a source of new hair cells, divide in response to hair cell ablation, expanding the possible progenitor pool. In parallel, nascent hair cells arise from direct transdifferentiation of progenitor pool cells uncoupled from progenitor division. These findings reveal a previously unrecognized mechanism of hair cell regeneration with implications for how hair cells may be encouraged to regenerate in the mammalian ear.
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Affiliation(s)
- Marielle O. Beaulieu
- Molecular and Cellular Biology Graduate Program, Seattle, WA
- Virginia Merrill Bloedel Hearing Research Center, Department of Otolaryngology - Head and Neck Surgery, Seattle, WA
| | - Eric D. Thomas
- Neuroscience Graduate Program, Seattle, WA
- Department of Biological Structure University of Washington, Seattle, WA
| | - David W. Raible
- Molecular and Cellular Biology Graduate Program, Seattle, WA
- Virginia Merrill Bloedel Hearing Research Center, Department of Otolaryngology - Head and Neck Surgery, Seattle, WA
- Neuroscience Graduate Program, Seattle, WA
- Department of Biological Structure University of Washington, Seattle, WA
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4
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Sun P, Smith E, Nicolson T. Transmembrane Channel-Like (Tmc) Subunits Contribute to Frequency Sensitivity in the Zebrafish Utricle. J Neurosci 2024; 44:e1298232023. [PMID: 37952940 PMCID: PMC10851681 DOI: 10.1523/jneurosci.1298-23.2023] [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: 07/12/2023] [Revised: 08/25/2023] [Accepted: 09/16/2023] [Indexed: 11/14/2023] Open
Abstract
Information about dynamic head motion is conveyed by a central "striolar" zone of vestibular hair cells and afferent neurons in the inner ear. How vestibular hair cells are tuned to transduce dynamic stimuli at the molecular level is not well understood. Here we take advantage of the differential expression pattern of tmc1, tmc2a, and tmc2b, which encode channel subunits of the mechanotransduction complex in zebrafish vestibular hair cells. To test the role of various combinations of Tmc subunits in transducing dynamic head movements, we measured reflexive eye movements induced by high-frequency stimuli in single versus double tmc mutants. We found that Tmc2a function correlates with the broadest range of frequency sensitivity, whereas Tmc2b mainly contributes to lower-frequency responses. Tmc1, which is largely excluded from the striolar zone, plays a minor role in sensing lower-frequency stimuli. Our study suggests that the Tmc subunits impart functional differences to the mechanotransduction of dynamic stimuli.Significance Statement Information about dynamic head movements is transmitted by sensory receptors, known as hair cells, in the labyrinth of the inner ear. The sensitivity of hair cells to fast or slow movements of the head differs according to cell type. Whether the mechanotransduction complex that converts mechanical stimuli into electrical signals in hair cells participates in conveying frequency information is not clear. Here we find that the transmembrane channel-like 1/2 genes, which encode a central component of the complex, are differentially expressed in the utricle and contribute to frequency sensitivity in zebrafish.
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Affiliation(s)
- Peng Sun
- Department of Otolaryngology, Stanford University, Stanford, California 94304
| | - Eliot Smith
- Department of Otolaryngology, Stanford University, Stanford, California 94304
| | - Teresa Nicolson
- Department of Otolaryngology, Stanford University, Stanford, California 94304
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5
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Liu Z, Bagnall MW. Organization of vestibular circuits for postural control in zebrafish. Curr Opin Neurobiol 2023; 82:102776. [PMID: 37634321 DOI: 10.1016/j.conb.2023.102776] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2023] [Revised: 07/28/2023] [Accepted: 08/01/2023] [Indexed: 08/29/2023]
Abstract
Most animals begin controlling their posture, or orientation with respect to gravity, at an early stage in life. Posture is vital for locomotor function. Even animals like fish, which are capable of swimming upside-down, must actively control their orientation to coordinate behaviors such as capturing prey near the water's surface. Here we review recent research from multiple laboratories investigating the organization and function of the vestibular circuits underlying postural control in zebrafish. Some findings in zebrafish strongly align with prior observations in mammals, reinforcing our understanding of homologies between systems. In other instances, the unique transparency and accessibility of zebrafish has enabled new analyses of several neural circuit components that remain challenging to study in mammalian systems. These new results demonstrate topographical and circuit features in postural control.
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Affiliation(s)
- Zhikai Liu
- Department of Neuroscience, Washington University in St. Louis, 660 S. Euclid Ave., St. Louis MO 63108, USA; Department of Cell Biology, Harvard Medical School, Boston, MA 02115, USA. https://twitter.com/zhikai_liu
| | - Martha W Bagnall
- Department of Neuroscience, Washington University in St. Louis, 660 S. Euclid Ave., St. Louis MO 63108, USA.
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6
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Beiza-Canelo N, Moulle H, Pujol T, Panier T, Migault G, Le Goc G, Tapie P, Desprat N, Straka H, Debrégeas G, Bormuth V. Magnetic actuation of otoliths allows behavioral and brain-wide neuronal exploration of vestibulo-motor processing in larval zebrafish. Curr Biol 2023:S0960-9822(23)00621-8. [PMID: 37285844 DOI: 10.1016/j.cub.2023.05.026] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2022] [Revised: 11/23/2022] [Accepted: 05/11/2023] [Indexed: 06/09/2023]
Abstract
The vestibular system in the inner ear plays a central role in sensorimotor control by informing the brain about the orientation and acceleration of the head. However, most experiments in neurophysiology are performed using head-fixed configurations, depriving animals of vestibular inputs. To overcome this limitation, we decorated the utricular otolith of the vestibular system in larval zebrafish with paramagnetic nanoparticles. This procedure effectively endowed the animal with magneto-sensitive capacities: applied magnetic field gradients induced forces on the otoliths, resulting in robust behavioral responses comparable to those evoked by rotating the animal by up to 25°. We recorded the whole-brain neuronal response to this fictive motion stimulation using light-sheet functional imaging. Experiments performed in unilaterally injected fish revealed the activation of a commissural inhibition between the brain hemispheres. This magnetic-based stimulation technique for larval zebrafish opens new perspectives to functionally dissect the neural circuits underlying vestibular processing and to develop multisensory virtual environments, including vestibular feedback.
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Affiliation(s)
- Natalia Beiza-Canelo
- Sorbonne Université, CNRS, Institut de Biologie Paris-Seine (IBPS), Laboratoire Jean Perrin (LJP), 75005 Paris, France
| | - Hippolyte Moulle
- Sorbonne Université, CNRS, Institut de Biologie Paris-Seine (IBPS), Laboratoire Jean Perrin (LJP), 75005 Paris, France
| | - Thomas Pujol
- Sorbonne Université, CNRS, Institut de Biologie Paris-Seine (IBPS), Laboratoire Jean Perrin (LJP), 75005 Paris, France; IBENS, Département de Biologie, École Normale Supérieure, CNRS, Inserm, PSL Research University, 75005 Paris, France
| | - Thomas Panier
- Sorbonne Université, CNRS, Institut de Biologie Paris-Seine (IBPS), Laboratoire Jean Perrin (LJP), 75005 Paris, France; Sorbonne Université, CNRS, Institut de Biologie Paris-Seine (IBPS), Plateforme d'Imagerie, 75005 Paris, France
| | - Geoffrey Migault
- Sorbonne Université, CNRS, Institut de Biologie Paris-Seine (IBPS), Laboratoire Jean Perrin (LJP), 75005 Paris, France
| | - Guillaume Le Goc
- Sorbonne Université, CNRS, Institut de Biologie Paris-Seine (IBPS), Laboratoire Jean Perrin (LJP), 75005 Paris, France
| | - Pierre Tapie
- Sorbonne Université, CNRS, Institut de Biologie Paris-Seine (IBPS), Laboratoire Jean Perrin (LJP), 75005 Paris, France
| | - Nicolas Desprat
- Laboratoire de Physique de l'École Normale Supérieure, ENS, Université PSL, CNRS, Sorbonne Université, Université Paris Cité, 75005 Paris, France; Université Paris Diderot, 10 Rue Alice Domon et Leonie Duquet, 75013 Paris, France
| | - Hans Straka
- Faculty of Biology, Ludwig-Maximilians-University Munich, Grosshadernerstr. 2, 82152 Planegg, Germany
| | - Georges Debrégeas
- Sorbonne Université, CNRS, Institut de Biologie Paris-Seine (IBPS), Laboratoire Jean Perrin (LJP), 75005 Paris, France
| | - Volker Bormuth
- Sorbonne Université, CNRS, Institut de Biologie Paris-Seine (IBPS), Laboratoire Jean Perrin (LJP), 75005 Paris, France.
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7
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Hamling KR, Harmon K, Schoppik D. The Nature and Origin of Synaptic Inputs to Vestibulospinal Neurons in the Larval Zebrafish. eNeuro 2023; 10:10/6/ENEURO.0090-23.2023. [PMID: 37268420 DOI: 10.1523/eneuro.0090-23.2023] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2023] [Revised: 04/24/2023] [Accepted: 04/27/2023] [Indexed: 06/04/2023] Open
Abstract
Vestibulospinal neurons integrate sensed imbalance to regulate postural reflexes. As an evolutionarily conserved neural population, understanding their synaptic and circuit-level properties can offer insight into vertebrate antigravity reflexes. Motivated by recent work, we set out to verify and extend the characterization of vestibulospinal neurons in the larval zebrafish. Using current-clamp recordings together with stimulation, we observed that larval zebrafish vestibulospinal neurons are silent at rest, yet capable of sustained spiking following depolarization. Neurons responded systematically to a vestibular stimulus (translation in the dark); responses were abolished after chronic or acute loss of the utricular otolith. Voltage-clamp recordings at rest revealed strong excitatory inputs with a characteristic multimodal distribution of amplitudes, as well as strong inhibitory inputs. Excitatory inputs within a particular mode (amplitude range) routinely violated refractory period criteria and exhibited complex sensory tuning, suggesting a nonunitary origin. Next, using a unilateral loss-of-function approach, we characterized the source of vestibular inputs to vestibulospinal neurons from each ear. We observed systematic loss of high-amplitude excitatory inputs after utricular lesions ipsilateral, but not contralateral, to the recorded vestibulospinal neuron. In contrast, while some neurons had decreased inhibitory inputs after either ipsilateral or contralateral lesions, there were no systematic changes across the population of recorded neurons. We conclude that imbalance sensed by the utricular otolith shapes the responses of larval zebrafish vestibulospinal neurons through both excitatory and inhibitory inputs. Our findings expand our understanding of how a vertebrate model, the larval zebrafish, might use vestibulospinal input to stabilize posture. More broadly, when compared with recordings in other vertebrates, our data speak to conserved origins of vestibulospinal synaptic input.
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Affiliation(s)
- Kyla R Hamling
- Departments of Otolaryngology and Neuroscience & Physiology, and Neuroscience Institute, New York University Grossman School of Medicine, New York, New York 10016
| | - Katherine Harmon
- Departments of Otolaryngology and Neuroscience & Physiology, and Neuroscience Institute, New York University Grossman School of Medicine, New York, New York 10016
| | - David Schoppik
- Departments of Otolaryngology and Neuroscience & Physiology, and Neuroscience Institute, New York University Grossman School of Medicine, New York, New York 10016
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8
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Baeza-Loya S, Raible DW. Vestibular physiology and function in zebrafish. Front Cell Dev Biol 2023; 11:1172933. [PMID: 37143895 PMCID: PMC10151581 DOI: 10.3389/fcell.2023.1172933] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2023] [Accepted: 04/06/2023] [Indexed: 05/06/2023] Open
Abstract
The vestibular system of the inner ear provides information about head motion and spatial orientation relative to gravity to ensure gaze stability, balance, and postural control. Zebrafish, like humans, have five sensory patches per ear that serve as peripheral vestibular organs, with the addition of the lagena and macula neglecta. The zebrafish inner ear can be easily studied due to its accessible location, the transparent tissue of larval fish, and the early development of vestibular behaviors. Thus, zebrafish are an excellent model for studying the development, physiology, and function of the vestibular system. Recent work has made great strides to elucidate vestibular neural circuitry in fish, tracing sensory transmission from receptors in the periphery to central computational circuits driving vestibular reflexes. Here we highlight recent work that illuminates the functional organization of vestibular sensory epithelia, innervating first-order afferent neurons, and second-order neuronal targets in the hindbrain. Using a combination of genetic, anatomical, electrophysiological, and optical techniques, these studies have probed the roles of vestibular sensory signals in fish gaze, postural, and swimming behaviors. We discuss remaining questions in vestibular development and organization that are tractable in the zebrafish model.
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Affiliation(s)
| | - David W. Raible
- Virginia Merrill Bloedel Hearing Research Center, Department of Otolaryngology-HNS and Biological Structure, University of Washington, Seattle, WA, United States
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9
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Hamling KR, Harmon K, Schoppik D. The nature and origin of synaptic inputs to vestibulospinal neurons in the larval zebrafish. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.03.15.532859. [PMID: 36993365 PMCID: PMC10055124 DOI: 10.1101/2023.03.15.532859] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Vestibulospinal neurons integrate sensed imbalance to regulate postural reflexes. As an evolutionarily-conserved neural population, understanding their synaptic and circuit-level properties can offer insight into vertebrate antigravity reflexes. Motivated by recent work, we set out to verify and extend the characterization of vestibulospinal neurons in the larval zebrafish. Using current clamp recordings together with stimulation, we observed that larval zebrafish vestibulospinal neurons are silent at rest, yet capable of sustained spiking following depolarization. Neurons responded systematically to a vestibular stimulus (translation in the dark); responses were abolished after chronic or acute loss of the utricular otolith. Voltage clamp recordings at rest revealed strong excitatory inputs with a characteristic multimodal distribution of amplitudes, as well as strong inhibitory inputs. Excitatory inputs within a particular mode (amplitude range) routinely violated refractory period criteria and exhibited complex sensory tuning, suggesting a non-unitary origin. Next, using a unilateral loss-of-function approach, we characterized the source of vestibular inputs to vestibulospinal neurons from each ear. We observed systematic loss of high-amplitude excitatory inputs after utricular lesions ipsilateral, but not contralateral to the recorded vestibulospinal neuron. In contrast, while some neurons had decreased inhibitory inputs after either ipsilateral or contralateral lesions, there were no systematic changes across the population of recorded neurons. We conclude that imbalance sensed by the utricular otolith shapes the responses of larval zebrafish vestibulospinal neurons through both excitatory and inhibitory inputs. Our findings expand our understanding of how a vertebrate model, the larval zebrafish, might use vestibulospinal input to stabilize posture. More broadly, when compared to recordings in other vertebrates, our data speak to conserved origins of vestibulospinal synaptic input.
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Affiliation(s)
- Kyla R Hamling
- Departments of Otolaryngology, Neuroscience & Physiology, and the Neuroscience Institute, New York University Grossman School of Medicine
| | - Katherine Harmon
- Departments of Otolaryngology, Neuroscience & Physiology, and the Neuroscience Institute, New York University Grossman School of Medicine
| | - David Schoppik
- Departments of Otolaryngology, Neuroscience & Physiology, and the Neuroscience Institute, New York University Grossman School of Medicine
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10
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Biomechanics and neural circuits for vestibular-induced fine postural control in larval zebrafish. Nat Commun 2023; 14:1217. [PMID: 36898983 PMCID: PMC10006170 DOI: 10.1038/s41467-023-36682-y] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2022] [Accepted: 02/10/2023] [Indexed: 03/12/2023] Open
Abstract
Land-walking vertebrates maintain a desirable posture by finely controlling muscles. It is unclear whether fish also finely control posture in the water. Here, we showed that larval zebrafish have fine posture control. When roll-tilted, fish recovered their upright posture using a reflex behavior, which was a slight body bend near the swim bladder. The vestibular-induced body bend produces a misalignment between gravity and buoyancy, generating a moment of force that recovers the upright posture. We identified the neural circuits for the reflex, including the vestibular nucleus (tangential nucleus) through reticulospinal neurons (neurons in the nucleus of the medial longitudinal fasciculus) to the spinal cord, and finally to the posterior hypaxial muscles, a special class of muscles near the swim bladder. These results suggest that fish maintain a dorsal-up posture by frequently performing the body bend reflex and demonstrate that the reticulospinal pathway plays a critical role in fine postural control.
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11
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Shi T, Beaulieu MO, Saunders LM, Fabian P, Trapnell C, Segil N, Crump JG, Raible DW. Single-cell transcriptomic profiling of the zebrafish inner ear reveals molecularly distinct hair cell and supporting cell subtypes. eLife 2023; 12:82978. [PMID: 36598134 PMCID: PMC9851615 DOI: 10.7554/elife.82978] [Citation(s) in RCA: 22] [Impact Index Per Article: 22.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2022] [Accepted: 01/04/2023] [Indexed: 01/05/2023] Open
Abstract
A major cause of human deafness and vestibular dysfunction is permanent loss of the mechanosensory hair cells of the inner ear. In non-mammalian vertebrates such as zebrafish, regeneration of missing hair cells can occur throughout life. While a comparative approach has the potential to reveal the basis of such differential regenerative ability, the degree to which the inner ears of fish and mammals share common hair cells and supporting cell types remains unresolved. Here, we perform single-cell RNA sequencing of the zebrafish inner ear at embryonic through adult stages to catalog the diversity of hair cells and non-sensory supporting cells. We identify a putative progenitor population for hair cells and supporting cells, as well as distinct hair and supporting cell types in the maculae versus cristae. The hair cell and supporting cell types differ from those described for the lateral line system, a distributed mechanosensory organ in zebrafish in which most studies of hair cell regeneration have been conducted. In the maculae, we identify two subtypes of hair cells that share gene expression with mammalian striolar or extrastriolar hair cells. In situ hybridization reveals that these hair cell subtypes occupy distinct spatial domains within the three macular organs, the utricle, saccule, and lagena, consistent with the reported distinct electrophysiological properties of hair cells within these domains. These findings suggest that primitive specialization of spatially distinct striolar and extrastriolar hair cells likely arose in the last common ancestor of fish and mammals. The similarities of inner ear cell type composition between fish and mammals validate zebrafish as a relevant model for understanding inner ear-specific hair cell function and regeneration.
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Affiliation(s)
- Tuo Shi
- Department of Stem Cell Biology and Regenerative Medicine, Keck School of Medicine, University of Southern CaliforniaLos AngelesUnited States
- Caruso Department of Otolaryngology-Head and Neck Surgery, Keck School of Medicine, University of Southern CaliforniaLos AngelesUnited States
| | - Marielle O Beaulieu
- Department of Otolaryngology-Head and Neck Surgery, University of WashingtonSeattleUnited States
| | - Lauren M Saunders
- Department of Genome Sciences, University of WashingtonSeattleUnited States
| | - Peter Fabian
- Department of Stem Cell Biology and Regenerative Medicine, Keck School of Medicine, University of Southern CaliforniaLos AngelesUnited States
| | - Cole Trapnell
- Department of Genome Sciences, University of WashingtonSeattleUnited States
| | - Neil Segil
- Department of Stem Cell Biology and Regenerative Medicine, Keck School of Medicine, University of Southern CaliforniaLos AngelesUnited States
- Caruso Department of Otolaryngology-Head and Neck Surgery, Keck School of Medicine, University of Southern CaliforniaLos AngelesUnited States
| | - J Gage Crump
- Department of Stem Cell Biology and Regenerative Medicine, Keck School of Medicine, University of Southern CaliforniaLos AngelesUnited States
| | - David W Raible
- Department of Otolaryngology-Head and Neck Surgery, University of WashingtonSeattleUnited States
- Department of Genome Sciences, University of WashingtonSeattleUnited States
- Department of Biological Structure, University of WashingtonSeattleUnited States
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