Adult-born neurons facilitate olfactory bulb pattern separation during task engagement
Abstract
The rodent olfactory bulb incorporates thousands of newly generated inhibitory neurons daily throughout adulthood, but the role of adult neurogenesis in olfactory processing is not fully understood. Here we adopted a genetic method to inducibly suppress adult neurogenesis and investigated its effect on behavior and bulbar activity. Mice without young adult-born neurons (ABNs) showed normal ability in discriminating very different odorants but were impaired in fine discrimination. Furthermore, two-photon calcium imaging of mitral cells (MCs) revealed that the ensemble odor representations of similar odorants were more ambiguous in the ablation animals. This increased ambiguity was primarily due to a decrease in MC suppressive responses. Intriguingly, these deficits in MC encoding were only observed during task engagement but not passive exposure. Our results indicate that young olfactory ABNs are essential for the enhancement of MC pattern separation in a task engagement-dependent manner, potentially functioning as a gateway for top-down modulation.
Article and author information
Author details
Funding
National Institute on Deafness and Other Communication Disorders (R01 DC014690-01)
- Takaki Komiyama
Human Frontier Science Program
- Itaru Imayoshi
- Takaki Komiyama
Ministry of Education, Culture, Sports, Science, and Technology
- Itaru Imayoshi
Japan Science and Technology Agency
- Itaru Imayoshi
- Takaki Komiyama
National Institute on Deafness and Other Communication Disorders (R21 DC012641)
- Takaki Komiyama
National Institute on Deafness and Other Communication Disorders (U01 NS094342)
- Takaki Komiyama
National Eye Institute (P30EY022589)
- Takaki Komiyama
National Institute of Neurological Disorders and Stroke (R01 NS091010A)
- Takaki Komiyama
National Eye Institute (R01 EY025349)
- Takaki Komiyama
New York Stem Cell Foundation
- Takaki Komiyama
David and Lucile Packard Foundation
- Takaki Komiyama
Pew Charitable Trusts
- Takaki Komiyama
McKnight Foundation
- Takaki Komiyama
Kavli Foundation
- Takaki Komiyama
National Science Foundation (1734940)
- Takaki Komiyama
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Reviewing Editor
- Naoshige Uchida, Harvard University, United States
Ethics
Animal experimentation: All procedures were in accordance with protocols approved by the Institutional Animal Care and Use Committee at UCSD (protocol number s10221) or Kyoto University (permit number Med Kyo 16216) and guidelines of the National Institute of Health.
Version history
- Received: October 21, 2017
- Accepted: March 12, 2018
- Accepted Manuscript published: March 13, 2018 (version 1)
- Version of Record published: April 23, 2018 (version 2)
Copyright
© 2018, Li 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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