Identification of an inhibitory neuron subtype, the L-stellate cell of the cochlear nucleus

  1. Tenzin Ngodup
  2. Gabriel E Romero
  3. Laurence O Trussell  Is a corresponding author
  1. Oregon Health and Science University, United States

Abstract

Auditory processing depends upon inhibitory signaling by interneurons, even at its earliest stages in the ventral cochlear nucleus (VCN). Remarkably, to date only a single subtype of inhibitory neuron has been documented in the VCN, a projection neuron termed the D-stellate cell. With the use of a transgenic mouse line, optical clearing and imaging techniques, combined with electrophysiological tools, we revealed a population of glycinergic cells in the VCN distinct from the D-stellate cell. These multipolar glycinergic cells were smaller in soma size and dendritic area, but over 10-fold more numerous than D-stellate cells. They were activated by AN and T-stellate cells, and made local inhibitory synaptic contacts on principal cells of the VCN. Given their abundance, combined with their narrow dendritic fields and axonal projections, it is likely that these neurons, here termed L-stellate cells, play a significant role in frequency-specific processing of acoustic signals.

Data availability

Datasets have been uploaded to Dryad, with the DOI doi:10.5061/dryad.69p8cz8xpThese are referred to in the appropriate figure legends.

The following data sets were generated

Article and author information

Author details

  1. Tenzin Ngodup

    Vollum Institute; Oregon Hearing Research Center, Oregon Health and Science University, Portland, United States
    Competing interests
    The authors declare that no competing interests exist.
  2. Gabriel E Romero

    Physiology and Pharmacology Graduate Program, Oregon Health and Science University, Portland, United States
    Competing interests
    The authors declare that no competing interests exist.
  3. Laurence O Trussell

    Vollum Institute; Oregon Hearing Research Center, Oregon Health and Science University, Portland, United States
    For correspondence
    trussell@ohsu.edu
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-1171-2356

Funding

National Institutes of Health (NS028901)

  • Laurence O Trussell

National Institutes of Health (DC004450)

  • Laurence O Trussell

National Institutes of Health (P30NS061800)

  • Laurence O Trussell

Hearing Health Foundation (Emerging Research Grant)

  • Tenzin Ngodup

Howard Hughes Medical Institute (Gilliam Fellowship)

  • Gabriel E Romero

The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.

Ethics

Animal experimentation: This study was performed in strict accordance with the recommendations in the Guide for the Care and Use of Laboratory Animals of the National Institutes of Health. All experimental procedures were approved by the Oregon Health and Science University's Institutional Animal Care and Use Committee, under protocol IP00000952.

Reviewing Editor

  1. Dwight E Bergles, Johns Hopkins University School of Medicine, United States

Publication history

  1. Received: December 11, 2019
  2. Accepted: November 2, 2020
  3. Accepted Manuscript published: November 3, 2020 (version 1)
  4. Version of Record published: December 16, 2020 (version 2)

Copyright

© 2020, Ngodup et al.

This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.

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  1. Tenzin Ngodup
  2. Gabriel E Romero
  3. Laurence O Trussell
(2020)
Identification of an inhibitory neuron subtype, the L-stellate cell of the cochlear nucleus
eLife 9:e54350.
https://doi.org/10.7554/eLife.54350

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