Localization, proteomics, and metabolite profiling reveal a putative vesicular transporter for UDP-glucose
Abstract
Vesicular neurotransmitter transporters (VNTs) mediate the selective uptake and enrichment of small molecule neurotransmitters into synaptic vesicles (SVs) and are therefore a major determinant of the synaptic output of specific neurons. To identify novel VNTs expressed on SVs (thus identifying new neurotransmitters and/or neuromodulators), we conducted localization profiling of 361 solute carrier (SLC) transporters tagging with a fluorescent protein in neurons, which revealed 40 possible candidates through comparison with a known SV marker. We parallelly performed proteomics analysis of immunoisolated SVs and identified 7 transporters in overlap. Ultrastructural analysis confirmed one of the transporters, SLC35D3, localized to SVs. Finally, by combining metabolite profiling with a radiolabeled substrate transport assay, we identified UDP-glucose as the principal substrate for SLC35D3. These results provide new insights into the functional role of SLC transporters in neurotransmission and improve our understanding of the molecular diversity of chemical transmitters.
Data availability
All data generated or analysed during this study are included in the manuscript and supporting files.
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Author details
Funding
Beijing Municipal Science & Technology Commission (Z181100001318002)
- Yulong Li
Peking-Tsinghua Center for Life Sciences
- Yulong Li
State Key Laboratory of Membrane Biology
- Yulong Li
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 procedures were performed using protocols approved by the Institutional Animal Care and Use Committee at Peking University. ( LSC LiYL 1 )
Reviewing Editor
- Rebecca Seal, University of Pittsburgh School of Medicine, United States
Version history
- Received: December 3, 2020
- Accepted: July 15, 2021
- Accepted Manuscript published: July 16, 2021 (version 1)
- Version of Record published: August 18, 2021 (version 2)
Copyright
© 2021, Qian 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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