Protein composition of axonal dopamine release sites in the striatum
Abstract
Dopamine is an important modulator of cognition and movement. We recently found that evoked dopamine secretion is fast and relies on active zone-like release sites. Here, we used in vivo biotin-identification (iBioID) proximity proteomics in mouse striatum to assess which proteins are present at these sites. Using three release site baits, we identified proteins that are enriched over the general dopamine axonal protein content, and they fell into categories including active zone, Ca2+ regulatory and synaptic vesicle proteins. We also detected many proteins not previously associated with vesicular exocytosis. Knockout of the presynaptic organizer protein RIM strongly decreased the hit number obtained with iBioID, while Synaptotagmin-1 knockout did not. α-Synuclein, a protein linked to Parkinson's disease, was enriched at release sites, and its enrichment was lost in both tested mutants. We conclude that RIM organizes scaffolded dopamine release sites and provide a proteomic assessment of the composition of these sites.
Data availability
All data generated or analyzed in this study are included in the figures and the source data tables. Source data files are provided for Figs. 1 to 3, Fig. 1 - figure supplement 2, Fig. 2 - figure supplements 1 and 2, and Fig. 3 - figure supplements 1 and 2.
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Author details
Funding
National Institute of Neurological Disorders and Stroke (R01NS103484)
- Pascal S Kaeser
National Institute of Neurological Disorders and Stroke (R01NS083898)
- Pascal S Kaeser
National Institute of Neurological Disorders and Stroke (F31NS105159)
- Lauren Kershberg
Harvard Medical School (Lefler Foundation)
- Pascal S Kaeser
Harvard Medical School (Brooks Fellowship)
- Aditi Banerjee
Harvard Medical School (Quan Fellowship)
- Lauren Kershberg
Harvard Medical School (Dean's Innovation Grant)
- Pascal S Kaeser
Harvard Medical School
- Pascal S Kaeser
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 animal experiments were performed according to institutional guidelines of Harvard University, and were in strict accordance with the recommendations in the Guide for the Care and Use of Laboratory Animals of the National Institutes of Health. All animal experiments were approved by the Harvard University Animal Care and Use Committee (protocol number IS00000049).
Copyright
© 2022, Kershberg 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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