--- _id: '7005' abstract: - lang: eng text: 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. article_processing_charge: No article_type: original author: - first_name: Giselle T full_name: Cheung, Giselle T id: 471195F6-F248-11E8-B48F-1D18A9856A87 last_name: Cheung orcid: 0000-0001-8457-2572 - first_name: Michael A. full_name: Cousin, Michael A. last_name: Cousin citation: ama: Cheung GT, Cousin MA. Synaptic vesicle generation from activity‐dependent bulk endosomes requires a dephosphorylation‐dependent dynamin–syndapin interaction. Journal of Neurochemistry. 2019;151(5):570-583. doi:10.1111/jnc.14862 apa: 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. Wiley. https://doi.org/10.1111/jnc.14862 chicago: 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. https://doi.org/10.1111/jnc.14862. ieee: 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, vol. 151, no. 5. Wiley, pp. 570–583, 2019. ista: Cheung GT, Cousin MA. 2019. Synaptic vesicle generation from activity‐dependent bulk endosomes requires a dephosphorylation‐dependent dynamin–syndapin interaction. Journal of Neurochemistry. 151(5), 570–583. mla: 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, vol. 151, no. 5, Wiley, 2019, pp. 570–83, doi:10.1111/jnc.14862. short: G.T. Cheung, M.A. Cousin, Journal of Neurochemistry 151 (2019) 570–583. date_created: 2019-11-12T14:37:08Z date_published: 2019-12-01T00:00:00Z date_updated: 2023-08-30T07:21:50Z day: '01' ddc: - '570' department: - _id: SiHi doi: 10.1111/jnc.14862 external_id: isi: - '000490703100001' pmid: - '31479508' file: - access_level: open_access checksum: ec1fb2aebb874009bc309adaada6e1d7 content_type: application/pdf creator: dernst date_created: 2020-02-05T10:30:02Z date_updated: 2020-07-14T12:47:47Z file_id: '7452' file_name: 2019_JournNeurochemistry_Cheung.pdf file_size: 4334962 relation: main_file file_date_updated: 2020-07-14T12:47:47Z has_accepted_license: '1' intvolume: ' 151' isi: 1 issue: '5' language: - iso: eng month: '12' oa: 1 oa_version: Published Version page: 570-583 pmid: 1 publication: Journal of Neurochemistry publication_identifier: eissn: - 1471-4159 issn: - 0022-3042 publication_status: published publisher: Wiley quality_controlled: '1' scopus_import: '1' status: public title: Synaptic vesicle generation from activity‐dependent bulk endosomes requires a dephosphorylation‐dependent dynamin–syndapin interaction tmp: image: /images/cc_by.png legal_code_url: https://creativecommons.org/licenses/by/4.0/legalcode name: Creative Commons Attribution 4.0 International Public License (CC-BY 4.0) short: CC BY (4.0) type: journal_article user_id: 4359f0d1-fa6c-11eb-b949-802e58b17ae8 volume: 151 year: '2019' ...