Clathrin coat controls synaptic vesicle acidification by blocking vacuolar ATPase activity
- Max Planck Institute for Biophysical Chemistry, Germany
- European Neuroscience Institute (ENI), Germany
- Sciloop, Germany
- Max Delbrück Center for Molecular Medicine, Germany
- University of Texas Health Science Center, United States
- Kungliga Tekniska Högskolan, Sweden
Abstract
Newly-formed synaptic vesicles (SVs) are rapidly acidified by vacuolar adenosine triphosphatases (vATPases), generating a proton electrochemical gradient that drives neurotransmitter loading. Clathrin-mediated endocytosis is needed for the formation of new SVs, yet it is unclear when endocytosed vesicles acidify and refill at the synapse. Here, we isolated clathrin-coated vesicles (CCVs) from mouse brain to measure their acidification directly at the single vesicle level. We observed that the ATP-induced acidification of CCVs was strikingly reduced in comparison to SVs. Remarkably, when the coat was removed from CCVs, uncoated vesicles regained ATP-dependent acidification, demonstrating that CCVs contain the functional vATPase, yet its function is inhibited by the clathrin coat. Considering the known structures of the vATPase and clathrin coat, we propose a model in which the formation of the coat surrounds the vATPase and blocks its activity. Such inhibition is likely fundamental for the proper timing of SV refilling.
Data availability
The structure has been deposited with the EMDB-ID #4335.For additional information considering structure please contact Prof Dr Carsten Mim at carsten.mim@ki.se
Article and author information
Author details
Funding
Deutsche Forschungsgemeinschaft (Emmy Noether Young Investigator Award MI-1702/1)
- Ira Milosevic
Human Frontier Science Program (Young Investigator Grant RGY0074/16)
- Carsten Mim
Schram Stiftung (T287/25457)
- Ira Milosevic
Engelhorn Stiftung (Postdoc fellowship)
- Zohreh Farsi
Synaptic System PhD fellowship (PhD fellowship)
- Sindhuja Gowrisankaran
National Institutes of Health (GM118933)
- Eileen M Lafer
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Animal experimentation: Animal experiments were conducted according to the European Guidelines for animal welfare (2010/63/EU) with approval by the Lower Saxony Landesamt fur Verbraucherschutz und Lebensmittelsicherheit (LAVES), registration number 14/1701.
Copyright
© 2018, Farsi 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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Clathrin coat controls synaptic vesicle acidification by blocking vacuolar ATPase activity
eLife 7:e32569.
https://doi.org/10.7554/eLife.32569
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