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Maraslioglu-Sperber A, Pizzi E, Fisch JO, Kattler K, Ritter T, Friauf E. Molecular and functional profiling of cell diversity and identity in the lateral superior olive, an auditory brainstem center with ascending and descending projections. Front Cell Neurosci 2024; 18:1354520. [PMID: 38846638 PMCID: PMC11153811 DOI: 10.3389/fncel.2024.1354520] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2023] [Accepted: 03/15/2024] [Indexed: 06/09/2024] Open
Abstract
The lateral superior olive (LSO), a prominent integration center in the auditory brainstem, contains a remarkably heterogeneous population of neurons. Ascending neurons, predominantly principal neurons (pLSOs), process interaural level differences for sound localization. Descending neurons (lateral olivocochlear neurons, LOCs) provide feedback into the cochlea and are thought to protect against acoustic overload. The molecular determinants of the neuronal diversity in the LSO are largely unknown. Here, we used patch-seq analysis in mice at postnatal days P10-12 to classify developing LSO neurons according to their functional and molecular profiles. Across the entire sample (n = 86 neurons), genes involved in ATP synthesis were particularly highly expressed, confirming the energy expenditure of auditory neurons. Two clusters were identified, pLSOs and LOCs. They were distinguished by 353 differentially expressed genes (DEGs), most of which were novel for the LSO. Electrophysiological analysis confirmed the transcriptomic clustering. We focused on genes affecting neuronal input-output properties and validated some of them by immunohistochemistry, electrophysiology, and pharmacology. These genes encode proteins such as osteopontin, Kv11.3, and Kvβ3 (pLSO-specific), calcitonin-gene-related peptide (LOC-specific), or Kv7.2 and Kv7.3 (no DEGs). We identified 12 "Super DEGs" and 12 genes showing "Cluster similarity." Collectively, we provide fundamental and comprehensive insights into the molecular composition of individual ascending and descending neurons in the juvenile auditory brainstem and how this may relate to their specific functions, including developmental aspects.
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Affiliation(s)
- Ayse Maraslioglu-Sperber
- Animal Physiology Group, Department of Biology, University of Kaiserslautern-Landau, Kaiserslautern, Germany
| | - Erika Pizzi
- Animal Physiology Group, Department of Biology, University of Kaiserslautern-Landau, Kaiserslautern, Germany
| | - Jonas O. Fisch
- Animal Physiology Group, Department of Biology, University of Kaiserslautern-Landau, Kaiserslautern, Germany
| | - Kathrin Kattler
- Genetics/Epigenetics Group, Department of Biological Sciences, Saarland University, Saarbrücken, Germany
| | - Tamara Ritter
- Animal Physiology Group, Department of Biology, University of Kaiserslautern-Landau, Kaiserslautern, Germany
| | - Eckhard Friauf
- Animal Physiology Group, Department of Biology, University of Kaiserslautern-Landau, Kaiserslautern, Germany
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2
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Pal I, Bhattacharyya A, V-Ghaffari B, Williams ED, Xiao M, Rutherford MA, Rubio ME. Female GluA3-KO mice show early onset hearing loss and afferent swellings in ambient sound levels. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.02.21.581467. [PMID: 38659964 PMCID: PMC11042237 DOI: 10.1101/2024.02.21.581467] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/26/2024]
Abstract
AMPA-type glutamate receptors (AMPAR) mediate excitatory cochlear transmission. However, the unique roles of AMPAR subunits are unresolved. Lack of subunit GluA3 (Gria3KO) in male mice reduced cochlear output by 8-weeks of age. Since Gria3 is X-linked and considering sex differences in hearing vulnerability, we hypothesized accelerated presbycusis in Gria3KO females. Here, auditory brainstem responses (ABR) were similar in 3-week-old female Gria3WT and Gria3KO mice. However, when raised in ambient sound, ABR thresholds were elevated and wave-1 amplitudes were diminished at 5-weeks and older in Gria3KO. In contrast, these metrics were similar between genotypes when raised in quiet. Paired synapses were similar in number, but lone ribbons and ribbonless synapses were increased in female Gria3KO mice in ambient sound compared to Gria3WT or to either genotype raised in quiet. Synaptic GluA4:GluA2 ratios increased relative to Gria3WT, particularly in ambient sound, suggesting an activity-dependent increase in calcium-permeable AMPARs in Gria3KO. Swollen afferent terminals were observed by 5-weeks only in Gria3KO females reared in ambient sound. We propose that lack of GluA3 induces sex-dependent vulnerability to AMPAR-mediated excitotoxicity.
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Affiliation(s)
- Indra Pal
- Department of Neurobiology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15261
| | - Atri Bhattacharyya
- Department of Otolaryngology, Washington University School of Medicine, St. Louis, MO 63110
| | - Babak V-Ghaffari
- Department of Otolaryngology, Washington University School of Medicine, St. Louis, MO 63110
| | - Essence D. Williams
- Department of Neurobiology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15261
| | - Maolei Xiao
- Department of Otolaryngology, Washington University School of Medicine, St. Louis, MO 63110
| | - Mark A. Rutherford
- Department of Otolaryngology, Washington University School of Medicine, St. Louis, MO 63110
| | - María Eulalia Rubio
- Department of Neurobiology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15261
- Department of Otolaryngology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15261
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Kelly L, Brown C, Gibbard AG, Jackson T, Swinny JD. Subunit-specific expression and function of AMPA receptors in the mouse locus coeruleus. J Anat 2023; 243:813-825. [PMID: 37391270 PMCID: PMC10557397 DOI: 10.1111/joa.13922] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2023] [Revised: 06/17/2023] [Accepted: 06/19/2023] [Indexed: 07/02/2023] Open
Abstract
The locus coeruleus (LC) provides the principal supply of noradrenaline (NA) to the brain, thereby modulating an array of brain functions. The release of NA, and therefore its impact on the brain, is governed by LC neuronal excitability. Glutamatergic axons, from various brain regions, topographically innervate different LC sub-domains and directly alter LC excitability. However, it is currently unclear whether glutamate receptor sub-classes, such as α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptors, are divergently expressed throughout the LC. Immunohistochemistry and confocal microscopy were used to identify and localise individual GluA subunits in the mouse LC. Whole-cell patch clamp electrophysiology and subunit-preferring ligands were used to assess their impact on LC spontaneous firing rate (FR). GluA1 immunoreactive clusters were associated with puncta immunoreactive for VGLUT2 on somata, and VGLUT1 on distal dendrites. GluA4 was associated with these synaptic markers only in the distal dendrites. No specific signal was detected for the GluA2-3 subunits. The GluA1/2 receptor agonist (S)-CPW 399 increased LC FR, whilst the GluA1/3 receptor antagonist philanthotoxin-74 decreased it. 4-[2-(phenylsulfonylamino)ethylthio]-2,6-difluoro-phenoxyacetamide (PEPA), a positive allosteric modulator of GluA3/4 receptors, had no significant effect on spontaneous FR. The data suggest distinct AMPA receptor subunits are targeted to different LC afferent inputs and have contrasting effects on spontaneous neuronal excitability. This precise expression profile could be a mechanism for LC neurons to integrate diverse information contained in various glutamate afferents.
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Affiliation(s)
- Louise Kelly
- School of Pharmacy & Biomedical SciencesUniversity of PortsmouthPortsmouthUK
| | - Christopher Brown
- School of Pharmacy & Biomedical SciencesUniversity of PortsmouthPortsmouthUK
| | - Adina G. Gibbard
- School of Pharmacy & Biomedical SciencesUniversity of PortsmouthPortsmouthUK
| | - Torquil Jackson
- School of Pharmacy & Biomedical SciencesUniversity of PortsmouthPortsmouthUK
| | - Jerome D. Swinny
- School of Pharmacy & Biomedical SciencesUniversity of PortsmouthPortsmouthUK
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Jing J, Hu M, Ngodup T, Ma Q, Lau SNN, Ljungberg C, McGinley MJ, Trussell LO, Jiang X. Comprehensive analysis of cellular specializations that initiate parallel auditory processing pathways in mice. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.05.15.539065. [PMID: 37293040 PMCID: PMC10245571 DOI: 10.1101/2023.05.15.539065] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
The cochlear nuclear complex (CN) is the starting point for all central auditory processing and comprises a suite of neuronal cell types that are highly specialized for neural coding of acoustic signals. To examine how their striking functional specializations are determined at the molecular level, we performed single-nucleus RNA sequencing of the mouse CN to molecularly define all constituent cell types and related them to morphologically- and electrophysiologically-defined neurons using Patch-seq. We reveal an expanded set of molecular cell types encompassing all previously described major types and discover new subtypes both in terms of topographic and cell-physiologic properties. Our results define a complete cell-type taxonomy in CN that reconciles anatomical position, morphological, physiological, and molecular criteria. This high-resolution account of cellular heterogeneity and specializations from the molecular to the circuit level illustrates molecular underpinnings of functional specializations and enables genetic dissection of auditory processing and hearing disorders with unprecedented specificity.
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Affiliation(s)
- Junzhan Jing
- Jan and Dan Duncan Neurological Research Institute at Texas Children’s Hospital, Houston, TX, USA
- Department of Neuroscience, Baylor College of Medicine, Houston, TX, USA
| | - Ming Hu
- Jan and Dan Duncan Neurological Research Institute at Texas Children’s Hospital, Houston, TX, USA
- Department of Neuroscience, Baylor College of Medicine, Houston, TX, USA
| | - Tenzin Ngodup
- Oregon Hearing Research Center and Vollum Institute, Oregon Health and Science University, Portland, OR, USA
| | - Qianqian Ma
- Jan and Dan Duncan Neurological Research Institute at Texas Children’s Hospital, Houston, TX, USA
- Department of Neuroscience, Baylor College of Medicine, Houston, TX, USA
| | - Shu-Ning Natalie Lau
- Jan and Dan Duncan Neurological Research Institute at Texas Children’s Hospital, Houston, TX, USA
- Department of Neuroscience, Baylor College of Medicine, Houston, TX, USA
| | - Cecilia Ljungberg
- Jan and Dan Duncan Neurological Research Institute at Texas Children’s Hospital, Houston, TX, USA
- Department of Pediatrics, Baylor College of Medicine, Houston, TX, USA
| | - Matthew J. McGinley
- Jan and Dan Duncan Neurological Research Institute at Texas Children’s Hospital, Houston, TX, USA
- Department of Neuroscience, Baylor College of Medicine, Houston, TX, USA
| | - Laurence O. Trussell
- Oregon Hearing Research Center and Vollum Institute, Oregon Health and Science University, Portland, OR, USA
| | - Xiaolong Jiang
- Jan and Dan Duncan Neurological Research Institute at Texas Children’s Hospital, Houston, TX, USA
- Department of Neuroscience, Baylor College of Medicine, Houston, TX, USA
- Department of Ophthalmology, Baylor College of Medicine, Houston, TX, USA
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Wang M, Zhang C, Lin S, Xie R. Dendritic Degeneration and Altered Synaptic Innervation of a Central Auditory Neuron During Age-related Hearing Loss. Neuroscience 2023; 514:25-37. [PMID: 36738912 PMCID: PMC9992229 DOI: 10.1016/j.neuroscience.2023.01.037] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2022] [Revised: 01/08/2023] [Accepted: 01/30/2023] [Indexed: 02/05/2023]
Abstract
Cellular morphology and synaptic configuration are key determinants of neuronal function and are often modified under pathological conditions. In the first nucleus of the central auditory system, the cochlear nucleus (CN), principal bushy neurons specialize in processing temporal information of sound critical for hearing. These neurons alter their physiological properties during aging that contribute to age-related hearing loss (ARHL). The structural basis of such changes remains unclear, especially age-related modifications in their dendritic morphology and the innervating auditory nerve (AN) synapses. Using young (2-5 months) and aged (28-33 months) CBA/CaJ mice of either sex, we filled individual bushy neurons with fluorescent dye in acute brain slices to characterize their dendritic morphology, followed by immunostaining against vesicular glutamate transporter 1 (VGluT1) and calretinin (CR) to identify innervating AN synapses. We found that dendritic morphology of aged bushy neurons had significantly reduced complexity, suggesting age-dependent dendritic degeneration, especially in neurons with predominantly non-CR-expressing synapses on the soma. These dendrites were innervated by AN bouton synapses, which were predominantly non-CR-expressing in young mice but had increased proportion of CR-expressing synapses in old mice. While somatic AN synapses degenerated substantially with age, as quantified by VGluT1-labeled puncta volume, no significant difference was observed in the total volume of dendritic synapses between young and old mice. Consequently, synaptic density on dendrites was significantly higher in old mice. The findings suggest that dendritic degeneration and altered synaptic innervation in bushy neurons during aging may underlie their changed physiological activity and contribute to the development of ARHL.
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Affiliation(s)
- Meijian Wang
- Department of Otolaryngology, The Ohio State University, Columbus, OH, USA
| | - Chuangeng Zhang
- Department of Otolaryngology, The Ohio State University, Columbus, OH, USA
| | - Shengyin Lin
- Department of Otolaryngology, The Ohio State University, Columbus, OH, USA
| | - Ruili Xie
- Department of Otolaryngology, The Ohio State University, Columbus, OH, USA; Department of Neuroscience, The Ohio State University, Columbus, OH, USA.
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Rutherford MA, Bhattacharyya A, Xiao M, Cai HM, Pal I, Rubio ME. GluA3 subunits are required for appropriate assembly of AMPAR GluA2 and GluA4 subunits on cochlear afferent synapses and for presynaptic ribbon modiolar-pillar morphology. eLife 2023; 12:e80950. [PMID: 36648432 PMCID: PMC9891727 DOI: 10.7554/elife.80950] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2022] [Accepted: 01/16/2023] [Indexed: 01/18/2023] Open
Abstract
Cochlear sound encoding depends on α-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid receptors (AMPARs), but reliance on specific pore-forming subunits is unknown. With 5-week-old male C57BL/6J Gria3-knockout mice (i.e., subunit GluA3KO) we determined cochlear function, synapse ultrastructure, and AMPAR molecular anatomy at ribbon synapses between inner hair cells (IHCs) and spiral ganglion neurons. GluA3KO and wild-type (GluA3WT) mice reared in ambient sound pressure level (SPL) of 55-75 dB had similar auditory brainstem response (ABR) thresholds, wave-1 amplitudes, and latencies. Postsynaptic densities (PSDs), presynaptic ribbons, and synaptic vesicle sizes were all larger on the modiolar side of the IHCs from GluA3WT, but not GluA3KO, demonstrating GluA3 is required for modiolar-pillar synapse differentiation. Presynaptic ribbons juxtaposed with postsynaptic GluA2/4 subunits were similar in quantity, however, lone ribbons were more frequent in GluA3KO and GluA2-lacking synapses were observed only in GluA3KO. GluA2 and GluA4 immunofluorescence volumes were smaller on the pillar side than the modiolar side in GluA3KO, despite increased pillar-side PSD size. Overall, the fluorescent puncta volumes of GluA2 and GluA4 were smaller in GluA3KO than GluA3WT. However, GluA3KO contained less GluA2 and greater GluA4 immunofluorescence intensity relative to GluA3WT (threefold greater mean GluA4:GluA2 ratio). Thus, GluA3 is essential in development, as germline disruption of Gria3 caused anatomical synapse pathology before cochlear output became symptomatic by ABR. We propose the hearing loss in older male GluA3KO mice results from progressive synaptopathy evident in 5-week-old mice as decreased abundance of GluA2 subunits and an increase in GluA2-lacking, GluA4-monomeric Ca2+-permeable AMPARs.
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Affiliation(s)
- Mark A Rutherford
- Department of Otolaryngology, Washington University School of MedicineSt LouisUnited States
| | - Atri Bhattacharyya
- Department of Otolaryngology, Washington University School of MedicineSt LouisUnited States
| | - Maolei Xiao
- Department of Otolaryngology, Washington University School of MedicineSt LouisUnited States
| | - Hou-Ming Cai
- Department of Neurobiology, University of Pittsburgh School of MedicinePittsburghUnited States
| | - Indra Pal
- Department of Neurobiology, University of Pittsburgh School of MedicinePittsburghUnited States
| | - Maria Eulalia Rubio
- Department of Neurobiology, University of Pittsburgh School of MedicinePittsburghUnited States
- Department of Otolaryngology, University of Pittsburgh School of MedicinePittsburghUnited States
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7
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Lozier NR, Muscio S, Pal I, Cai HM, Rubio ME. Sex differences in glutamate AMPA receptor subunits mRNA with fast gating kinetics in the mouse cochlea. Front Syst Neurosci 2023; 17:1100505. [PMID: 36936507 PMCID: PMC10017478 DOI: 10.3389/fnsys.2023.1100505] [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: 11/16/2022] [Accepted: 01/30/2023] [Indexed: 03/06/2023] Open
Abstract
Evidence shows that females have increased supra-threshold peripheral auditory processing compared to males. This is indicated by larger auditory brainstem responses (ABR) wave I amplitude, which measures afferent spiral ganglion neuron (SGN)-auditory nerve synchrony. However, the underlying molecular mechanisms of this sex difference are mostly unknown. We sought to elucidate sex differences in ABR wave I amplitude by examining molecular markers known to affect synaptic transmission kinetics. Alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptors (AMPARs) mediate fast excitatory transmission in mature SGN afferent synapses. Each AMPAR channel is a tetramer composed of GluA2, 3, and 4 subunits (Gria2, 3, and 4 genes), and those lacking GluA2 subunits have larger currents, are calcium-permeable, and have faster gating kinetics. Moreover, alternatively spliced flip and flop isoforms of each AMPAR subunit affect channel kinetics, having faster kinetics those AMPARs containing Gria3 and Gria4 flop isoforms. We hypothesized that SGNs of females have more fast-gating AMPAR subunit mRNA than males, which could contribute to more temporally precise synaptic transmission and increased SGN synchrony. Our data show that the index of Gria3 relative to Gria2 transcripts on SGN was higher in females than males (females: 48%; males: 43%), suggesting that females have more SGNs with higher Gria3 mRNA relative to Gria2. Analysis of the relative abundance of the flip and flop alternatively spliced isoforms showed that females have a 2-fold increase in fast-gating Gria3 flop mRNA, while males have more slow-gating (2.5-fold) of the flip. We propose that Gria3 may in part mediate greater SGN synchrony in females. Significance Statement: Females of multiple vertebrate species, including fish and mammals, have been reported to have enhanced sound-evoked synchrony of afferents in the auditory nerve. However, the underlying molecular mediators of this physiologic sex difference are unknown. Elucidating potential molecular mechanisms related to sex differences in auditory processing is important for maintaining healthy ears and developing potential treatments for hearing loss in both sexes. This study found that females have a 2-fold increase in Gria3 flop mRNA, a fast-gating AMPA-type glutamate receptor subunit. This difference may contribute to greater neural synchrony in the auditory nerve of female mice compared to males, and this sex difference may be conserved in all vertebrates.
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Affiliation(s)
- Nicholas R. Lozier
- Department of Neurobiology, University of Pittsburgh, Pittsburgh, PA, United States
| | - Steven Muscio
- Department of Neurobiology, University of Pittsburgh, Pittsburgh, PA, United States
| | - Indra Pal
- Department of Neurobiology, University of Pittsburgh, Pittsburgh, PA, United States
| | - Hou-Ming Cai
- Department of Neurobiology, University of Pittsburgh, Pittsburgh, PA, United States
| | - María E. Rubio
- Department of Neurobiology, University of Pittsburgh, Pittsburgh, PA, United States
- Department of Otolaryngology, University of Pittsburgh, Pittsburgh, PA, United States
- Center for the Neural Basis of Cognition, University of Pittsburgh, Pittsburgh, PA, United States
- *Correspondence: María E. Rubio
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8
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Guerrero-Given D, Goldin SL, Thomas CI, Anthony SA, Jerez D, Kamasawa N. Gold In-and-Out: A Toolkit for Analyzing Subcellular Distribution of Immunogold-Labeled Membrane Proteins in Freeze-Fracture Replica Images. Front Neuroanat 2022; 16:855218. [PMID: 35444519 PMCID: PMC9014018 DOI: 10.3389/fnana.2022.855218] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2022] [Accepted: 03/04/2022] [Indexed: 11/13/2022] Open
Abstract
Integral membrane proteins such as ion channels, transporters, and receptors shape cell activity and mediate cell-to-cell communication in the brain. The distribution, quantity, and clustering arrangement of those proteins contribute to the physiological properties of the cell; therefore, precise quantification of their state can be used to gain insight into cellular function. Using a highly sensitive immunoelectron microscopy technique called sodium dodecyl sulfate-digested freeze-fracture replica immunogold labeling (SDS-FRL), multiple membrane proteins can be tagged with different sizes of immunogold particles at once and visualized two-dimensionally. For quantification, gold particles in the images must be annotated, and then different mathematical and statistical methods must be applied to characterize the distribution states of proteins of interest. To perform such analyses in a user-friendly manner, we developed a program with a simple graphical user interface called Gold In-and-Out (GIO), which integrates several classical and novel analysis methods for immunogold labeled replicas into one self-contained package. GIO takes an input of particle coordinates, then allows users to implement analysis methods such as nearest neighbor distance (NND) and particle clustering. The program not only performs the selected analysis but also automatically compares the results of the real distribution to a random distribution of the same number of particles on the membrane region of interest. In addition to classical approaches for analyzing protein distribution, GIO includes new tools to analyze the positional bias of a target protein relative to a morphological landmark such as dendritic spines, and can also be applied for synaptic protein analysis. Gold Rippler provides a normalized metric of particle density that is resistant to differences in labeling efficiency among samples, while Gold Star is useful for quantifying distances between a protein and landmark. This package aims to help standardize analysis methods for subcellular and synaptic protein localization with a user-friendly interface while increasing the efficiency of these time-consuming analyses.
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Affiliation(s)
| | | | | | | | | | - Naomi Kamasawa
- The Imaging Center and Electron Microscopy Core Facility, Max Planck Institute for Neuroscience, Jupiter, FL, United States
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Italia M, Ferrari E, Di Luca M, Gardoni F. GluA3-containing AMPA receptors: From physiology to synaptic dysfunction in brain disorders. Neurobiol Dis 2021; 161:105539. [PMID: 34743951 DOI: 10.1016/j.nbd.2021.105539] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2021] [Revised: 10/01/2021] [Accepted: 10/27/2021] [Indexed: 01/03/2023] Open
Abstract
In the mammalian brain, α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA)-type glutamate receptors (AMPARs) play a fundamental role in the activation of excitatory synaptic transmission and the induction of different forms of synaptic plasticity. The modulation of the AMPAR tetramer subunit composition at synapses defines the functional properties of the receptor. During the last twenty years, several studies have evaluated the roles played by each subunit, from GluA1 to GluA4, in both physiological and pathological conditions. Here, we have focused our attention on GluA3-containing AMPARs, addressing their functional role in synaptic transmission and synaptic plasticity and their involvement in a variety of brain disorders. Although several aspects remain to be fully understood, GluA3 is a widely expressed and functionally relevant subunit in AMPARs involved in several brain circuits, and its pharmacological modulation could represent a novel approach for the rescue of altered glutamatergic synapses associated with neurodegenerative and neurodevelopmental disorders.
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Affiliation(s)
- Maria Italia
- Department of Pharmacological and Biomolecular Sciences (DiSFeB), University of Milan, 20133 Milan, Italy
| | - Elena Ferrari
- Department of Pharmacological and Biomolecular Sciences (DiSFeB), University of Milan, 20133 Milan, Italy
| | - Monica Di Luca
- Department of Pharmacological and Biomolecular Sciences (DiSFeB), University of Milan, 20133 Milan, Italy
| | - Fabrizio Gardoni
- Department of Pharmacological and Biomolecular Sciences (DiSFeB), University of Milan, 20133 Milan, Italy.
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Walia A, Lee C, Hartsock J, Goodman SS, Dolle R, Salt AN, Lichtenhan JT, Rutherford MA. Reducing Auditory Nerve Excitability by Acute Antagonism of Ca 2+-Permeable AMPA Receptors. Front Synaptic Neurosci 2021; 13:680621. [PMID: 34290596 PMCID: PMC8287724 DOI: 10.3389/fnsyn.2021.680621] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2021] [Accepted: 05/31/2021] [Indexed: 11/13/2022] Open
Abstract
Hearing depends on glutamatergic synaptic transmission mediated by α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptors (AMPARs). AMPARs are tetramers, where inclusion of the GluA2 subunit reduces overall channel conductance and Ca2+ permeability. Cochlear afferent synapses between inner hair cells (IHCs) and auditory nerve fibers (ANFs) contain the AMPAR subunits GluA2, 3, and 4. However, the tetrameric complement of cochlear AMPAR subunits is not known. It was recently shown in mice that chronic intracochlear delivery of IEM-1460, an antagonist selective for GluA2-lacking AMPARs [also known as Ca2+-permeable AMPARs (CP-AMPARs)], before, during, and after acoustic overexposure prevented both the trauma to ANF synapses and the ensuing reduction of cochlear nerve activity in response to sound. Surprisingly, baseline measurements of cochlear function before exposure were unaffected by chronic intracochlear delivery of IEM-1460. This suggested that cochlear afferent synapses contain GluA2-lacking CP-AMPARs alongside GluA2-containing Ca2+-impermeable AMPA receptors (CI-AMPARs), and that the former can be antagonized for protection while the latter remain conductive. Here, we investigated hearing function in the guinea pig during acute local or systemic delivery of CP-AMPAR antagonists. Acute intracochlear delivery of IEM-1460 or systemic delivery of IEM-1460 or IEM-1925 reduced the amplitude of the ANF compound action potential (CAP) significantly, for all tone levels and frequencies, by > 50% without affecting CAP thresholds or distortion product otoacoustic emissions (DPOAE). Following systemic dosing, IEM-1460 levels in cochlear perilymph were ~ 30% of blood levels, on average, consistent with pharmacokinetic properties predicting permeation of the compounds into the brain and ear. Both compounds were metabolically stable with half-lives >5 h in vitro, and elimination half-lives in vivo of 118 min (IEM-1460) and 68 min (IEM-1925). Heart rate monitoring and off-target binding assays suggest an enhanced safety profile for IEM-1925 over IEM-1460. Compound potency on CAP reduction (IC50 ~ 73 μM IEM-1460) was consistent with a mixture of GluA2-lacking and GluA2-containing AMPARs. These data strongly imply that cochlear afferent synapses of the guinea pig contain GluA2-lacking CP-AMPARs. We propose these CP-AMPARs may be acutely antagonized with systemic dosing, to protect from glutamate excitotoxicity, while transmission at GluA2-containing AMPARs persists to mediate hearing during the protection.
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Affiliation(s)
- Amit Walia
- Department of Otolaryngology, Washington University in St. Louis School of Medicine, St. Louis, MO, United States
| | - Choongheon Lee
- Department of Otolaryngology, Washington University in St. Louis School of Medicine, St. Louis, MO, United States
| | - Jared Hartsock
- Department of Otolaryngology, Washington University in St. Louis School of Medicine, St. Louis, MO, United States
| | - Shawn S Goodman
- Department of Communication Sciences and Disorders, University of Iowa, Iowa City, IA, United States
| | - Roland Dolle
- Department of Biochemistry and Molecular Biophysics, Washington University Center for Drug Discovery, Washington University in St. Louis School of Medicine, St. Louis, MO, United States
| | - Alec N Salt
- Department of Otolaryngology, Washington University in St. Louis School of Medicine, St. Louis, MO, United States
| | - Jeffery T Lichtenhan
- Department of Otolaryngology, Washington University in St. Louis School of Medicine, St. Louis, MO, United States
| | - Mark A Rutherford
- Department of Otolaryngology, Washington University in St. Louis School of Medicine, St. Louis, MO, United States
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Bhandari P, Vandael D, Fernández-Fernández D, Fritzius T, Kleindienst D, Önal C, Montanaro J, Gassmann M, Jonas P, Kulik A, Bettler B, Shigemoto R, Koppensteiner P. GABA B receptor auxiliary subunits modulate Cav2.3-mediated release from medial habenula terminals. eLife 2021; 10:68274. [PMID: 33913808 PMCID: PMC8121548 DOI: 10.7554/elife.68274] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2021] [Accepted: 04/28/2021] [Indexed: 12/20/2022] Open
Abstract
The synaptic connection from medial habenula (MHb) to interpeduncular nucleus (IPN) is critical for emotion-related behaviors and uniquely expresses R-type Ca2+ channels (Cav2.3) and auxiliary GABAB receptor (GBR) subunits, the K+-channel tetramerization domain-containing proteins (KCTDs). Activation of GBRs facilitates or inhibits transmitter release from MHb terminals depending on the IPN subnucleus, but the role of KCTDs is unknown. We therefore examined the localization and function of Cav2.3, GBRs, and KCTDs in this pathway in mice. We show in heterologous cells that KCTD8 and KCTD12b directly bind to Cav2.3 and that KCTD8 potentiates Cav2.3 currents in the absence of GBRs. In the rostral IPN, KCTD8, KCTD12b, and Cav2.3 co-localize at the presynaptic active zone. Genetic deletion indicated a bidirectional modulation of Cav2.3-mediated release by these KCTDs with a compensatory increase of KCTD8 in the active zone in KCTD12b-deficient mice. The interaction of Cav2.3 with KCTDs therefore scales synaptic strength independent of GBR activation.
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Affiliation(s)
- Pradeep Bhandari
- Institute of Science and Technology Austria (IST Austria), Klosterneuburg, Austria
| | - David Vandael
- Institute of Science and Technology Austria (IST Austria), Klosterneuburg, Austria
| | | | | | - David Kleindienst
- Institute of Science and Technology Austria (IST Austria), Klosterneuburg, Austria
| | - Cihan Önal
- Institute of Science and Technology Austria (IST Austria), Klosterneuburg, Austria
| | - Jacqueline Montanaro
- Institute of Science and Technology Austria (IST Austria), Klosterneuburg, Austria
| | - Martin Gassmann
- Department of Biomedicine, University of Basel, Basel, Switzerland
| | - Peter Jonas
- Institute of Science and Technology Austria (IST Austria), Klosterneuburg, Austria
| | - Akos Kulik
- Institute of Physiology II, Faculty of Medicine, Freiburg, Germany.,BIOSS Centre for Biological Signalling Studies, University of Freiburg, Freiburg, Germany
| | - Bernhard Bettler
- Department of Biomedicine, University of Basel, Basel, Switzerland
| | - Ryuichi Shigemoto
- Institute of Science and Technology Austria (IST Austria), Klosterneuburg, Austria
| | - Peter Koppensteiner
- Institute of Science and Technology Austria (IST Austria), Klosterneuburg, Austria
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12
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Yan Y, Yang H, Xie Y, Ding Y, Kong D, Yu H. Research Progress on Alzheimer's Disease and Resveratrol. Neurochem Res 2020; 45:989-1006. [PMID: 32162143 DOI: 10.1007/s11064-020-03007-0] [Citation(s) in RCA: 43] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2019] [Revised: 02/27/2020] [Accepted: 03/03/2020] [Indexed: 12/13/2022]
Abstract
Alzheimer's disease (AD), a common irreversible neurodegenerative disease characterized by amyloid-β plaques, neurofibrillary tangles, and changes in tau phosphorylation, is accompanied by memory loss and symptoms of cognitive dysfunction. Increases in disease incidence due to the ageing of the population have placed a great burden on society. To date, the mechanism of AD and the identities of adequate drugs for AD prevention and treatment have eluded the medical community. It has been confirmed that phytochemicals have certain neuroprotective effects against AD. For example, some progress has been made in research on the use of resveratrol, a natural polyphenolic phytochemical, for the prevention and treatment of AD in recent years. Elucidation of the pathogenesis of AD will create a solid foundation for drug treatment. In addition, research on resveratrol, including its mechanism of action, the roles of signalling pathways and its therapeutic targets, will provide new ideas for AD treatment, which is of great significance. In this review, we discuss the possible relationships between AD and the following factors: synapses, α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA)-type glutamate receptors (AMPARs), silent information regulator 1 (SIRT1), and estrogens. We also discuss the findings of previous studies regarding these relationships in the context of AD treatment and further summarize research progress related to resveratrol treatment.
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Affiliation(s)
- Yan Yan
- The Department of Epidemiology and Health Statistics, Public Health School of Guangdong Medical University, Dongguan, 523808, Guangdong, China
| | - Huihuang Yang
- The Department of Epidemiology and Health Statistics, Public Health School of Guangdong Medical University, Dongguan, 523808, Guangdong, China
| | - Yuxun Xie
- The Department of Epidemiology and Health Statistics, Public Health School of Guangdong Medical University, Dongguan, 523808, Guangdong, China
| | - Yuanlin Ding
- The Department of Epidemiology and Health Statistics, Public Health School of Guangdong Medical University, Dongguan, 523808, Guangdong, China
| | - Danli Kong
- The Department of Epidemiology and Health Statistics, Public Health School of Guangdong Medical University, Dongguan, 523808, Guangdong, China.
| | - Haibing Yu
- The Department of Epidemiology and Health Statistics, Public Health School of Guangdong Medical University, Dongguan, 523808, Guangdong, China.
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13
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Role of GluA3 AMPA Receptor Subunits in the Presynaptic and Postsynaptic Maturation of Synaptic Transmission and Plasticity of Endbulb-Bushy Cell Synapses in the Cochlear Nucleus. J Neurosci 2020; 40:2471-2484. [PMID: 32051325 DOI: 10.1523/jneurosci.2573-19.2020] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2019] [Revised: 01/22/2020] [Accepted: 02/02/2020] [Indexed: 11/21/2022] Open
Abstract
The AMPA receptor (AMPAR) subunit GluA3 has been suggested to shape synaptic transmission and activity-dependent plasticity in endbulb-bushy cell synapses (endbulb synapses) in the anteroventral cochlear nucleus, yet the specific roles of GluA3 in the synaptic transmission at endbulb synapses remains unexplored. Here, we compared WT and GluA3 KO mice of both sexes and identified several important roles of GluA3 in the maturation of synaptic transmission and short-term plasticity in endbulb synapses. We show that GluA3 largely determines the ultrafast kinetics of endbulb synapses glutamatergic currents by promoting the insertion of postsynaptic AMPARs that contain fast desensitizing flop subunits. In addition, GluA3 is also required for the normal function, structure, and development of the presynaptic terminal which leads to altered short term-depression in GluA3 KO mice. The presence of GluA3 reduces and slows synaptic depression, which is achieved by lowering the probability of vesicle release, promoting efficient vesicle replenishment, and increasing the readily releasable pool of synaptic vesicles. Surprisingly, GluA3 also makes the speed of synaptic depression rate-invariant. We propose that the slower and rate-invariant speed of depression allows an initial response window that still contains presynaptic firing rate information before the synapse is depressed. Because this response window is rate-invariant, GluA3 extends the range of presynaptic firing rates over which rate information in bushy cells can be preserved. This novel role of GluA3 may be important to allowing the postsynaptic targets of spherical bushy cells in mice use rate information for encoding sound intensity and sound localization.SIGNIFICANCE STATEMENT We report novel roles of the glutamate receptor subunit GluA3 in synaptic transmission in synapses between auditory nerve fibers and spherical bushy cells (BCs) in the cochlear nucleus. We show that GluA3 contributes to the generation of ultrafast glutamatergic currents at these synapses, which is important to preserve temporal information about the sound. Furthermore, we demonstrate that GluA3 contributes to the normal function and development of the presynaptic terminal, whose properties shape short-term plasticity. GluA3 slows and attenuates synaptic depression, and makes it less dependent on the presynaptic firing rates. This may help BCs to transfer information about the high rates of activity that occur at the synapse in vivo to postsynaptic targets that use rate information for sound localization.
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14
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Ultrastructural and molecular features of excitatory and glutamatergic synapses. The auditory nerve synapses. VITAMINS AND HORMONES 2020; 114:23-51. [PMID: 32723545 DOI: 10.1016/bs.vh.2020.04.010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Glutamatergic synapses mediate fast synaptic transmission in the central nervous system. New developments highlight the importance of the synapse structural and molecular remodeling during development, aging and in neurological disorders. This chapter summarizes key structural and molecular aspects of the presynaptic and postsynaptic components of glutamatergic synapses in the brain. In addition, this chapter describes how the structure of the postsynaptic density and ionotropic glutamate content contribute to the function of auditory nerve synapses in the lower auditory brainstem.
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15
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Kuenzel T. Modulatory influences on time-coding neurons in the ventral cochlear nucleus. Hear Res 2019; 384:107824. [DOI: 10.1016/j.heares.2019.107824] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/10/2019] [Revised: 09/10/2019] [Accepted: 10/14/2019] [Indexed: 02/07/2023]
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16
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Taylor BK, Sinha GP, Donahue RR, Grachen CM, Morón JA, Doolen S. Opioid receptors inhibit the spinal AMPA receptor Ca 2+ permeability that mediates latent pain sensitization. Exp Neurol 2019; 314:58-66. [PMID: 30660616 DOI: 10.1016/j.expneurol.2019.01.003] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2018] [Revised: 12/24/2018] [Accepted: 01/05/2019] [Indexed: 01/02/2023]
Abstract
Acute inflammation induces sensitization of nociceptive neurons and triggers the accumulation of calcium permeable (CP) α-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid receptors (AMPARs) in the dorsal horn of the spinal cord. This coincides with behavioral signs of acute inflammatory pain, but whether CP-AMPARs contribute to chronic pain remains unclear. To evaluate this question, we first constructed current-voltage (IV) curves of C-fiber stimulus-evoked, AMPAR-mediated EPSCs in lamina II to test for inward rectification, a key characteristic of CP-AMPARs. We found that the intraplantar injection of complete Freund's adjuvant (CFA) induced an inward rectification at 3 d that persisted to 21 d after injury. Furthermore, the CP- AMPAR antagonist IEM-1460 (50 μM) inhibited AMPAR-evoked Ca2+ transients 21d after injury but had no effect in uninflamed mice. We then used a model of long-lasting vulnerability for chronic pain that is determined by the balance between latent central sensitization (LCS) and mu opioid receptor constitutive activity (MORCA). When administered 21 d after the intraplantar injection of CFA, intrathecal administration of the MORCA inverse agonist naltrexone (NTX, 1 μg, i.t.) reinstated mechanical hypersensitivity, and superfusion of spinal cord slices with NTX (10 μM) increased the peak amplitude of AMPAR-evoked Ca2+ transients in lamina II neurons. The CP-AMPAR antagonist naspm (0-10 nmol, i.t.) inhibited these NTX-induced increases in mechanical hypersensitivity. NTX had no effect in uninflamed mice. Subsequent western blot analysis of the postsynaptic density membrane fraction from lumbar dorsal horn revealed that CFA increased GluA1 expression at 2 d and GluA4 expression at both 2 and 21 d post-injury, indicating that not just the GluA1 subunit, but also the GluA4 subunit, contributes to the expression of CP-AMPARs and synaptic strength during hyperalgesia. GluA2 expression increased at 21 d, an unexpected result that requires further study. We conclude that after tissue injury, dorsal horn AMPARs retain a Ca2+ permeability that underlies LCS. Because of their effectiveness in reducing naltrexone-induced reinstatement of hyperalgesia and potentiation of AMPAR-evoked Ca2+ signals, CP-AMPAR inhibitors are a promising class of agents for the treatment of chronic inflammatory pain.
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Affiliation(s)
- Bradley K Taylor
- Department of Anesthesiology, Pittsburgh Center for Pain Research, University of Pittsburgh School of Medicine, 200 Lothrop St. Pittsburgh, PA 15213, USA; Department of Physiology, University of Kentucky School of Medicine, 800 Rose, St. Lexington, KY 40536-0298, USA.
| | - Ghanshyam P Sinha
- Department of Anesthesiology, Pittsburgh Center for Pain Research, University of Pittsburgh School of Medicine, 200 Lothrop St. Pittsburgh, PA 15213, USA; Department of Physiology, University of Kentucky School of Medicine, 800 Rose, St. Lexington, KY 40536-0298, USA.
| | - Renee R Donahue
- Department of Physiology, University of Kentucky School of Medicine, 800 Rose, St. Lexington, KY 40536-0298, USA.
| | - Carolyn M Grachen
- Department of Anesthesiology, Pittsburgh Center for Pain Research, University of Pittsburgh School of Medicine, 200 Lothrop St. Pittsburgh, PA 15213, USA; Department of Physiology, University of Kentucky School of Medicine, 800 Rose, St. Lexington, KY 40536-0298, USA.
| | - Jose A Morón
- Department of Anesthesiology, Washington University Pain Center, Washington University School of Medicine, 600 South Euclid, St Louis, MO 63110, USA.
| | - Suzanne Doolen
- Department of Anesthesiology, Pittsburgh Center for Pain Research, University of Pittsburgh School of Medicine, 200 Lothrop St. Pittsburgh, PA 15213, USA; Department of Physiology, University of Kentucky School of Medicine, 800 Rose, St. Lexington, KY 40536-0298, USA.
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17
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The ion channels and synapses responsible for the physiological diversity of mammalian lower brainstem auditory neurons. Hear Res 2018; 376:33-46. [PMID: 30606624 DOI: 10.1016/j.heares.2018.12.011] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/06/2018] [Revised: 12/12/2018] [Accepted: 12/22/2018] [Indexed: 11/20/2022]
Abstract
The auditory part of the brainstem is composed of several nuclei specialized in the computation of the different spectral and temporal features of the sound before it reaches the higher auditory regions. There are a high diversity of neuronal types in these nuclei, many with remarkable electrophysiological and synaptic properties unique to these structures. This diversity reflects specializations necessary to process the different auditory signals in order to extract precisely the acoustic information necessary for the auditory perception by the animal. Low threshold Kv1 channels and HCN channels are expressed in neurons that use timing clues for auditory processing, like bushy and octopus cells, in order to restrict action potential firing and reduce input resistance and membrane time constant. Kv3 channels allow principal neurons of the MNTB and pyramidal DCN neurons to fire fast trains of action potentials. Calcium channels on cartwheel DCN neurons produce complex spikes characteristic of these neurons. Calyceal synapses compensate the low input resistance of bushy and principal neurons of the MNTB by releasing hundreds of glutamate vesicles resulting in large EPSCs acting in fast ionotropic glutamate receptors, in order to reduce temporal summation of synaptic potentials, allowing more precise correspondence of pre- and post-synaptic potentials, and phase-locking. Pre-synaptic calyceal sodium channels have fast recovery from inactivation allowing extremely fast trains of action potential firing, and persistent sodium channels produce spontaneous activity of fusiform neurons at rest, which expands the dynamic range of these neurons. The unique combinations of different ion channels, ionotropic receptors and synaptic structures create a unique functional diversity of neurons extremely adapted to their complex functions in the auditory processing.
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18
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Lee JY, Krieger J, Herguedas B, García-Nafría J, Dutta A, Shaikh SA, Greger IH, Bahar I. Druggability Simulations and X-Ray Crystallography Reveal a Ligand-Binding Site in the GluA3 AMPA Receptor N-Terminal Domain. Structure 2018; 27:241-252.e3. [PMID: 30528594 DOI: 10.1016/j.str.2018.10.017] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2018] [Revised: 07/25/2018] [Accepted: 10/18/2018] [Indexed: 11/19/2022]
Abstract
Ionotropic glutamate receptors (iGluRs) mediate the majority of excitatory neurotransmission in the brain. Their dysfunction is implicated in many neurological disorders, rendering iGluRs potential drug targets. Here, we performed a systematic analysis of the druggability of two major iGluR subfamilies, using molecular dynamics simulations in the presence of drug-like molecules. We demonstrate the applicability of druggability simulations by faithfully identifying known agonist and modulator sites on AMPA receptors (AMPARs) and NMDA receptors. Simulations produced the expected allosteric changes of the AMPAR ligand-binding domain in response to agonist. We also identified a novel ligand-binding site specific to the GluA3 AMPAR N-terminal domain (NTD), resulting from its unique conformational flexibility that we explored further with crystal structures trapped in vastly different states. In addition to providing an in-depth analysis into iGluR NTD dynamics, our approach identifies druggable sites and permits the determination of pharmacophoric features toward novel iGluR modulators.
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Affiliation(s)
- Ji Young Lee
- Department of Computational and Systems Biology, School of Medicine, University of Pittsburgh, 3501 Fifth Avenue, Suite 3064 BST3, Pittsburgh, PA 15260, USA
| | - James Krieger
- Department of Computational and Systems Biology, School of Medicine, University of Pittsburgh, 3501 Fifth Avenue, Suite 3064 BST3, Pittsburgh, PA 15260, USA
| | - Beatriz Herguedas
- Neurobiology Division, MRC Laboratory of Molecular Biology, Cambridge Biomedical Campus, Francis Crick Avenue, Cambridge CB2 0QH, UK
| | - Javier García-Nafría
- Neurobiology Division, MRC Laboratory of Molecular Biology, Cambridge Biomedical Campus, Francis Crick Avenue, Cambridge CB2 0QH, UK
| | - Anindita Dutta
- Department of Computational and Systems Biology, School of Medicine, University of Pittsburgh, 3501 Fifth Avenue, Suite 3064 BST3, Pittsburgh, PA 15260, USA
| | - Saher A Shaikh
- Neurobiology Division, MRC Laboratory of Molecular Biology, Cambridge Biomedical Campus, Francis Crick Avenue, Cambridge CB2 0QH, UK
| | - Ingo H Greger
- Neurobiology Division, MRC Laboratory of Molecular Biology, Cambridge Biomedical Campus, Francis Crick Avenue, Cambridge CB2 0QH, UK.
| | - Ivet Bahar
- Department of Computational and Systems Biology, School of Medicine, University of Pittsburgh, 3501 Fifth Avenue, Suite 3064 BST3, Pittsburgh, PA 15260, USA.
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Pre- and postsynaptic ionotropic glutamate receptors in the auditory system of mammals. Hear Res 2018; 362:1-13. [DOI: 10.1016/j.heares.2018.02.007] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/01/2017] [Revised: 02/16/2018] [Accepted: 02/21/2018] [Indexed: 01/22/2023]
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