Oligodendrocytes regulate presynaptic properties and neurotransmission through BDNF signaling in the mouse brainstem
Neuron-glia communication contributes to the precise control of synaptic functions. Oligodendrocytes near synapses detect and respond to neuronal activity, but their role in synapse development and plasticity remains largely unexplored. We show that oligodendrocytes modulate neurotransmitter release at presynaptic terminals through secretion of brain derived neurotrophic factor (BDNF). Oligodendrocyte-derived BDNF functions via presynaptic tropomyosin receptor kinase B (TrkB) to ensure fast, reliable neurotransmitter release and auditory transmission in the developing brain. In auditory brainstem slices from Bdnf+/- mice, reduction in endogenous BDNF significantly decreased vesicular glutamate release by reducing the readily releasable pool of glutamate vesicles, without altering presynaptic Ca2+ channel activation or release probability. Using conditional knockout mice, cell-specific ablation of BDNF in oligodendrocytes largely recapitulated this effect, which was recovered by BDNF or TrkB agonist application. This study highlights a novel function for oligodendrocytes in synaptic transmission and their potential role in activity-dependent refinement of presynaptic properties.
All data generated or analysed during this study are included in the manuscript and supporting files.
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National Institute on Deafness and Other Communication Disorders (R01 DC03157)
- Jun Hee Kim
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Animal experimentation: All animal procedures were performed in accordance with the guidelines approved by the University of Texas Health Science Center, San Antonio (UTHSCSA) Institutional Animal Care and Use Committee protocols (#140045x).
- Dwight E Bergles, Johns Hopkins University School of Medicine, United States
- Received: September 21, 2018
- Accepted: April 17, 2019
- Accepted Manuscript published: April 18, 2019 (version 1)
- Version of Record published: May 7, 2019 (version 2)
© 2019, Jang 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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