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Leary P, Bellegarda C, Quainoo C, Goldblatt D, Rosti B, Schoppik D. Development of the Motor Periphery is the Rate-Limiting Step in the Ontogeny of the Vestibulo-ocular Reflex. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.05.17.594732. [PMID: 38798369 PMCID: PMC11118585 DOI: 10.1101/2024.05.17.594732] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2024]
Abstract
Sensory deprivation reshapes developing neural circuits, and sensory feedback adjusts the strength of reflexive behaviors throughout life. Sensory development might therefore limit the rate with which behaviors mature, but the complexity of most sensorimotor circuits preclude identifying this fundamental constraint. Here we compared the functional development of components of the vertebrate vestibulo-ocular reflex circuit that stabilizes gaze. We found that vestibular interneuron responses to body tilt sensation developed well before behavioral performance peaked, even without motor neuron-derived feedback. Motor neuron responses developed similarly. Instead, the ontogeny of behavior matched the rate of neuromuscular junction development. When sensation was delayed until after the neuromuscular junction developed, behavioral performance was immediately strong. The matching timecourse and ability to determine behavior establish the development of the neuromuscular junction, and not sensory-derived information, as the rate-limiting process for an ancient and evolutionarilyconserved neural circuit.
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Affiliation(s)
- Paige Leary
- Depts. of Otolaryngology, Neuroscience & Physiology, and the Neuroscience Institute, NYU Grossman School of Medicine
| | - Celine Bellegarda
- Depts. of Otolaryngology, Neuroscience & Physiology, and the Neuroscience Institute, NYU Grossman School of Medicine
| | - Cheryl Quainoo
- Depts. of Otolaryngology, Neuroscience & Physiology, and the Neuroscience Institute, NYU Grossman School of Medicine
| | - Dena Goldblatt
- Depts. of Otolaryngology, Neuroscience & Physiology, and the Neuroscience Institute, NYU Grossman School of Medicine
- Center for Neural Science, New York University
| | - Başak Rosti
- Depts. of Otolaryngology, Neuroscience & Physiology, and the Neuroscience Institute, NYU Grossman School of Medicine
| | - David Schoppik
- Depts. of Otolaryngology, Neuroscience & Physiology, and the Neuroscience Institute, NYU Grossman School of Medicine
- Lead Contact
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2
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Fritzsch B. Evolution and development of extraocular motor neurons, nerves and muscles in vertebrates. Ann Anat 2024; 253:152225. [PMID: 38346566 DOI: 10.1016/j.aanat.2024.152225] [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] [Received: 11/02/2023] [Revised: 01/16/2024] [Accepted: 02/05/2024] [Indexed: 02/17/2024]
Abstract
The purpose of this review is to analyze the origin of ocular motor neurons, define the pattern of innervation of nerve fibers that project to the extraocular eye muscles (EOMs), describe congenital disorders that alter the development of ocular motor neurons, and provide an overview of vestibular pathway inputs to ocular motor nuclei. Six eye muscles are innervated by axons of three ocular motor neurons, the oculomotor (CNIII), trochlear (CNIV), and abducens (CNVI) neurons. Ocular motor neurons (CNIII) originate in the midbrain and innervate the ipsilateral orbit, except for the superior rectus and the levator palpebrae, which are contralaterally innervated. Trochlear motor neurons (CNIV) originate at the midbrain-hindbrain junction and innervate the contralateral superior oblique muscle. Abducens motor neurons (CNVI) originate variously in the hindbrain of rhombomeres r4-6 that innervate the posterior (or lateral) rectus muscle and innervate the retractor bulbi. Genes allow a distinction between special somatic (CNIII, IV) and somatic (CNVI) ocular motor neurons. Development of ocular motor neurons and their axonal projections to the EOMs may be derailed by various genetic causes, resulting in the congenital cranial dysinnervation disorders. The ocular motor neurons innervate EOMs while the vestibular nuclei connect with the midbrain-brainstem motor neurons.
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Affiliation(s)
- Bernd Fritzsch
- Department of Neurological Sciences, University of Nebraska Medical Center, NE, USA.
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3
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Zhu Y, Gelnaw H, Auer F, Hamling KR, Ehrlich DE, Schoppik D. A brainstem circuit for gravity-guided vertical navigation. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.03.12.584680. [PMID: 38559209 PMCID: PMC10980031 DOI: 10.1101/2024.03.12.584680] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/04/2024]
Abstract
The sensation of gravity anchors our perception of the environment and is crucial for navigation. However, the neural circuits that transform gravity into commands for navigation are undefined. We first determined that larval zebrafish (Danio rerio) navigate vertically by maintaining a consistent heading across a series of upward climb or downward dive bouts. Gravity-blind mutant fish swim with more variable heading and excessive veering, leading to inefficient vertical navigation. After targeted photoablation of ascending vestibular neurons and spinal projecting midbrain neurons, but not vestibulospinal neurons, vertical navigation was impaired. These data define a sensorimotor circuit that uses evolutionarily-conserved brainstem architecture to transform gravitational signals into persistent heading for vertical navigation. The work lays a foundation to understand how vestibular inputs allow animals to move efficiently through their environment.
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Affiliation(s)
- Yunlu Zhu
- Departments of Otolaryngology, Neuroscience & Physiology, and the Neuroscience Institute, New York University Grossman School of Medicine
| | - Hannah Gelnaw
- Departments of Otolaryngology, Neuroscience & Physiology, and the Neuroscience Institute, New York University Grossman School of Medicine
| | - Franziska Auer
- Departments of Otolaryngology, Neuroscience & Physiology, and the Neuroscience Institute, New York University Grossman School of Medicine
| | - Kyla R. Hamling
- Departments of Otolaryngology, Neuroscience & Physiology, and the Neuroscience Institute, New York University Grossman School of Medicine
| | - David E. Ehrlich
- 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
- Lead Contact
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4
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Hamid A, Gattuso H, Caglar AN, Pillai M, Steele T, Gonzalez A, Nagel K, Syed MH. The conserved RNA-binding protein Imp is required for the specification and function of olfactory navigation circuitry in Drosophila. Curr Biol 2024; 34:473-488.e6. [PMID: 38181792 PMCID: PMC10872534 DOI: 10.1016/j.cub.2023.12.020] [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: 05/19/2023] [Revised: 11/14/2023] [Accepted: 12/07/2023] [Indexed: 01/07/2024]
Abstract
Complex behaviors depend on the precise developmental specification of neuronal circuits, but the relationship between genetic programs for neural development, circuit structure, and behavioral output is often unclear. The central complex (CX) is a conserved sensory-motor integration center in insects, which governs many higher-order behaviors and largely derives from a small number of type II neural stem cells (NSCs). Here, we show that Imp, a conserved IGF-II mRNA-binding protein expressed in type II NSCs, plays a role in specifying essential components of CX olfactory navigation circuitry. We show the following: (1) that multiple components of olfactory navigation circuitry arise from type II NSCs. (2) Manipulating Imp expression in type II NSCs alters the number and morphology of many of these circuit elements, with the most potent effects on neurons targeting the ventral layers of the fan-shaped body (FB). (3) Imp regulates the specification of Tachykinin-expressing ventral FB input neurons. (4) Imp is required in type II NSCs for establishing proper morphology of the CX neuropil structures. (5) Loss of Imp in type II NSCs abolishes upwind orientation to attractive odor while leaving locomotion and odor-evoked regulation of movement intact. Taken together, our findings establish that a temporally expressed gene can regulate the expression of a complex behavior by developmentally regulating the specification of multiple circuit components and provides a first step toward a developmental dissection of the CX and its roles in behavior.
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Affiliation(s)
- Aisha Hamid
- Department of Biology, University of New Mexico, 219 Yale Blvd NE, Albuquerque, NM 87131, USA
| | - Hannah Gattuso
- Neuroscience Institute, NYU Medical Center, 435 E 30th St., New York, NY 10016, USA
| | - Aysu Nora Caglar
- Department of Biology, University of New Mexico, 219 Yale Blvd NE, Albuquerque, NM 87131, USA
| | - Midhula Pillai
- Neuroscience Institute, NYU Medical Center, 435 E 30th St., New York, NY 10016, USA
| | - Theresa Steele
- Neuroscience Institute, NYU Medical Center, 435 E 30th St., New York, NY 10016, USA
| | - Alexa Gonzalez
- Department of Biology, University of New Mexico, 219 Yale Blvd NE, Albuquerque, NM 87131, USA
| | - Katherine Nagel
- Neuroscience Institute, NYU Medical Center, 435 E 30th St., New York, NY 10016, USA.
| | - Mubarak Hussain Syed
- Department of Biology, University of New Mexico, 219 Yale Blvd NE, Albuquerque, NM 87131, USA.
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Goldblatt D, Rosti B, Hamling KR, Leary P, Panchal H, Li M, Gelnaw H, Huang S, Quainoo C, Schoppik D. Motor neurons are dispensable for the assembly of a sensorimotor circuit for gaze stabilization. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.01.25.577261. [PMID: 38328255 PMCID: PMC10849732 DOI: 10.1101/2024.01.25.577261] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/09/2024]
Abstract
Sensorimotor reflex circuits engage distinct neuronal subtypes, defined by precise connectivity, to transform sensation into compensatory behavior. Whether and how motor neuron populations specify the subtype fate and/or sensory connectivity of their pre-motor partners remains controversial. Here, we discovered that motor neurons are dispensable for proper connectivity in the vestibular reflex circuit that stabilizes gaze. We first measured activity following vestibular sensation in pre-motor projection neurons after constitutive loss of their extraocular motor neuron partners. We observed normal responses and topography indicative of unchanged functional connectivity between sensory neurons and projection neurons. Next, we show that projection neurons remain anatomically and molecularly poised to connect appropriately with their downstream partners. Lastly, we show that the transcriptional signatures that typify projection neurons develop independently of motor partners. Our findings comprehensively overturn a long-standing model: that connectivity in the circuit for gaze stabilization is retrogradely determined by motor partner-derived signals. By defining the contribution of motor neurons to specification of an archetypal sensorimotor circuit, our work speaks to comparable processes in the spinal cord and advances our understanding of general principles of neural development.
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Affiliation(s)
- Dena Goldblatt
- Depts. of Otolaryngology, Neuroscience & Physiology, and the Neuroscience Institute, NYU Langone Health
- Center for Neural Science, New York University
| | - Başak Rosti
- Depts. of Otolaryngology, Neuroscience & Physiology, and the Neuroscience Institute, NYU Langone Health
| | - Kyla R. Hamling
- Depts. of Otolaryngology, Neuroscience & Physiology, and the Neuroscience Institute, NYU Langone Health
| | - Paige Leary
- Depts. of Otolaryngology, Neuroscience & Physiology, and the Neuroscience Institute, NYU Langone Health
| | - Harsh Panchal
- Depts. of Otolaryngology, Neuroscience & Physiology, and the Neuroscience Institute, NYU Langone Health
| | - Marlyn Li
- Depts. of Otolaryngology, Neuroscience & Physiology, and the Neuroscience Institute, NYU Langone Health
- Center for Neural Science, New York University
| | - Hannah Gelnaw
- Depts. of Otolaryngology, Neuroscience & Physiology, and the Neuroscience Institute, NYU Langone Health
| | - Stephanie Huang
- Depts. of Otolaryngology, Neuroscience & Physiology, and the Neuroscience Institute, NYU Langone Health
- Center for Neural Science, New York University
| | - Cheryl Quainoo
- Depts. of Otolaryngology, Neuroscience & Physiology, and the Neuroscience Institute, NYU Langone Health
| | - David Schoppik
- Depts. of Otolaryngology, Neuroscience & Physiology, and the Neuroscience Institute, NYU Langone Health
- Lead Contact
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6
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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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7
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Hamid A, Gattuso H, Caglar AN, Pillai M, Steele T, Gonzalez A, Nagel K, Syed MH. The RNA-binding protein, Imp specifies olfactory navigation circuitry and behavior in Drosophila. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.05.26.542522. [PMID: 37398350 PMCID: PMC10312496 DOI: 10.1101/2023.05.26.542522] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/04/2023]
Abstract
Complex behaviors depend on the precise developmental specification of neuronal circuits, but the relationship between genetic prograssms for neural development, circuit structure, and behavioral output is often unclear. The central complex (CX) is a conserved sensory-motor integration center in insects that governs many higher order behaviors and largely derives from a small number of Type II neural stem cells. Here, we show that Imp, a conserved IGF-II mRNA-binding protein expressed in Type II neural stem cells, specifies components of CX olfactory navigation circuitry. We show: (1) that multiple components of olfactory navigation circuitry arise from Type II neural stem cells and manipulating Imp expression in Type II neural stem cells alters the number and morphology of many of these circuit elements, with the most potent effects on neurons targeting the ventral layers of the fan-shaped body. (2) Imp regulates the specification of Tachykinin expressing ventral fan-shaped body input neurons. (3) Imp in Type II neural stem cells alters the morphology of the CX neuropil structures. (4) Loss of Imp in Type II neural stem cells abolishes upwind orientation to attractive odor while leaving locomotion and odor-evoked regulation of movement intact. Taken together, our work establishes that a single temporally expressed gene can regulate the expression of a complex behavior through the developmental specification of multiple circuit components and provides a first step towards a developmental dissection of the CX and its roles in behavior.
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Affiliation(s)
- Aisha Hamid
- Department of Biology, 219 Yale Blvd NE, University of New Mexico, Albuquerque, NM 87131, USA
| | - Hannah Gattuso
- Neuroscience Institute, NYU Medical Center, 435 E 30th St., New York, NY 10016, USA
| | - Aysu Nora Caglar
- Current address: Biochemistry & Molecular Biology, 915 Camino De Salud NE, Albuquerque, NM 87132, USA
| | - Midhula Pillai
- Neuroscience Institute, NYU Medical Center, 435 E 30th St., New York, NY 10016, USA
| | - Theresa Steele
- Neuroscience Institute, NYU Medical Center, 435 E 30th St., New York, NY 10016, USA
| | - Alexa Gonzalez
- Department of Biology, 219 Yale Blvd NE, University of New Mexico, Albuquerque, NM 87131, USA
| | - Katherine Nagel
- Neuroscience Institute, NYU Medical Center, 435 E 30th St., New York, NY 10016, USA
| | - Mubarak Hussain Syed
- Department of Biology, 219 Yale Blvd NE, University of New Mexico, Albuquerque, NM 87131, USA
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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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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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