Synaptic vesicle generation from activity‐dependent bulk endosomes requires a dephosphorylation‐dependent dynamin–syndapin interaction

G.T. Cheung, M.A. Cousin, Journal of Neurochemistry (2019).

Download
OA 8.78 MB

Journal Article | Epub ahead of print | English
Author
;
Department
Abstract
Activity-dependent bulk endocytosis generates synaptic vesicles (SVs) during intense neuronal activity via a two-step process. First, bulk endosomes are formed direct from the plasma membrane from which SVs are then generated. SV generation from bulk endosomes requires the efflux of previously accumulated calcium and activation of the protein phosphatase calcineurin. However, it is still unknown how calcineurin mediates SV generation. We addressed this question using a series of acute interventions that decoupled the generation of SVs from bulk endosomes in rat primary neuronal culture. This was achieved by either disruption of protein–protein interactions via delivery of competitive peptides, or inhibition of enzyme activity by known inhibitors. SV generation was monitored using either a morphological horseradish peroxidase assay or an optical assay that monitors the replenishment of the reserve SV pool. We found that SV generation was inhibited by, (i) peptides that disrupt calcineurin interactions, (ii) an inhibitor of dynamin I GTPase activity and (iii) peptides that disrupt the phosphorylation-dependent dynamin I–syndapin I interaction. Peptides that disrupted syndapin I interactions with eps15 homology domain-containing proteins had no effect. This revealed that (i) calcineurin must be localized at bulk endosomes to mediate its effect, (ii) dynamin I GTPase activity is essential for SV fission and (iii) the calcineurin-dependent interaction between dynamin I and syndapin I is essential for SV generation. We therefore propose that a calcineurin-dependent dephosphorylation cascade that requires both dynamin I GTPase and syndapin I lipid-deforming activity is essential for SV generation from bulk endosomes.
Publishing Year
Date Published
2019-09-03
Journal Title
Journal of Neurochemistry
IST-REx-ID

Cite this

Cheung GT, Cousin MA. Synaptic vesicle generation from activity‐dependent bulk endosomes requires a dephosphorylation‐dependent dynamin–syndapin interaction. Journal of Neurochemistry. 2019. doi:10.1111/jnc.14862
Cheung, G. T., & Cousin, M. A. (2019). Synaptic vesicle generation from activity‐dependent bulk endosomes requires a dephosphorylation‐dependent dynamin–syndapin interaction. Journal of Neurochemistry. https://doi.org/10.1111/jnc.14862
Cheung, Giselle T, and Michael A. Cousin. “Synaptic Vesicle Generation from Activity‐dependent Bulk Endosomes Requires a Dephosphorylation‐dependent Dynamin–Syndapin Interaction.” Journal of Neurochemistry, 2019. https://doi.org/10.1111/jnc.14862.
G. T. Cheung and M. A. Cousin, “Synaptic vesicle generation from activity‐dependent bulk endosomes requires a dephosphorylation‐dependent dynamin–syndapin interaction,” Journal of Neurochemistry, 2019.
Cheung GT, Cousin MA. 2019. Synaptic vesicle generation from activity‐dependent bulk endosomes requires a dephosphorylation‐dependent dynamin–syndapin interaction. Journal of Neurochemistry.
Cheung, Giselle T., and Michael A. Cousin. “Synaptic Vesicle Generation from Activity‐dependent Bulk Endosomes Requires a Dephosphorylation‐dependent Dynamin–Syndapin Interaction.” Journal of Neurochemistry, Wiley, 2019, doi:10.1111/jnc.14862.
All files available under the following license(s):
Creative Commons License:
CC-BYCreative Commons Attribution 4.0 International Public License (CC-BY 4.0)
Main File(s)
Access Level
OA Open Access
Last Uploaded
2019-11-12T14:40:17Z


Export

Marked Publications

Open Data IST Research Explorer

Sources

PMID: 31479508
PubMed | Europe PMC

Search this title in

Google Scholar