A novel class of inferior colliculus principal neurons labeled in vasoactive intestinal peptide-cre mice
- University of Michigan, United States
- Northeast Ohio Medical University, United States
Abstract
Located in the midbrain, the inferior colliculus (IC) is the hub of the central auditory system. Although the IC plays important roles in speech processing, sound localization, and other auditory computations, the organization of the IC microcircuitry remains largely unknown. Using a multifaceted approach in mice, we have identified vasoactive intestinal peptide (VIP) neurons as a novel class of IC principal neurons. VIP neurons are glutamatergic stellate cells with sustained firing patterns. Their extensive axons project to long-range targets including the auditory thalamus, auditory brainstem, superior colliculus, and periaqueductal gray. Using optogenetic circuit mapping, we found that VIP neurons integrate input from the contralateral IC and the dorsal cochlear nucleus. The dorsal cochlear nucleus also drove feedforward inhibition to VIP neurons, indicating that inhibitory circuits within the IC shape the temporal integration of ascending inputs. Thus, VIP neurons are well-positioned to influence auditory computations in a number of brain regions.
Data availability
All data generated or analysed during this study are included in the manuscript and supporting files. Source data files have been provided for Figures 3, 4, 5, 7, and 8 and Table 2.
Article and author information
Author details
Michael Thomas Roberts
Funding
Deutsche Forschungsgemeinschaft (401540516)
- David Goyer
Hearing Health Foundation (Emerging Research Grant)
- Michael Thomas Roberts
National Institutes of Health (DC016880)
- Michael Thomas Roberts
National Institutes of Health (DC004391)
- Brett R Schofield
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Animal experimentation: All experiments were approved by the University of Michigan Institutional Animal Care and Use Committee (protocol # PRO00006642 and PRO00008773) and were in accordance with NIH guidelines for the care and use of laboratory animals.
Copyright
© 2019, Goyer 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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A novel class of inferior colliculus principal neurons labeled in vasoactive intestinal peptide-cre mice
eLife 8:e43770.
https://doi.org/10.7554/eLife.43770
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