title: A readily retrievable pool of synaptic vesicles.
abstract: Although clathrin-mediated endocytosis is thought to be the predominant mechanism of synaptic vesicle recycling, it seems to be too slow for fast recycling. Therefore, it was suggested that a presorted and preassembled pool of synaptic vesicle proteins on the presynaptic membrane might support a first wave of fast clathrin-mediated endocytosis. In this study we monitored the temporal dynamics of such a 'readily retrievable pool' of synaptic vesicle proteins in rat hippocampal neurons using a new type of probe. By applying cypHer5E, a new cyanine dye-based pH-sensitive exogenous marker, coupled to antibodies to luminal domains of synaptic vesicle proteins, we could reliably monitor synaptic vesicle recycling and demonstrate the preferential recruitment of a surface pool of synaptic vesicle proteins upon stimulated endocytosis. By using fluorescence nanoscopy of surface-labeled synaptotagmin 1, we could resolve the spatial distribution of the surface pool at the periactive zone in hippocampal boutons, which represent putative sites of endocytosis.
authors.affiliation: Department of Membrane Biophysics, Max Planck Institute for Biophysical Chemistry, Goettingen, Germany.
authors.forename: Yunfeng
authors.initials: Y
authors.lastname: Hua
authors.forename: Raunak
authors.initials: R
authors.lastname: Sinha
authors.forename: Cora S
authors.initials: CS
authors.lastname: Thiel
authors.forename: Roman
authors.initials: R
authors.lastname: Schmidt
authors.forename: Jana
authors.initials: J
authors.lastname: Hüve
authors.forename: Henrik
authors.initials: H
authors.lastname: Martens
authors.forename: Stefan W
authors.initials: SW
authors.lastname: Hell
authors.forename: Alexander
authors.initials: A
authors.lastname: Egner
authors.forename: Jurgen
authors.initials: J
authors.lastname: Klingauf
mesh_terms: D000818:Animals; D000831:Animals, Newborn; D002352:Carrier Proteins / Q000235:genetics / Q000378:metabolism; D002478:Cells, Cultured; D004705:Endocytosis / Q000235:genetics / Q000502:physiology; D006624:Hippocampus / Q000166:cytology; D000072233:Homer Scaffolding Proteins; D008856:Microscopy, Fluorescence / Q000379:methods; D009474:Neurons / Q000166:cytology* / Q000187:drug effects; D051381:Rats; D013569:Synapses / Q000235:genetics / Q000502:physiology*; D013572:Synaptic Vesicles / Q000502:physiology*; D014162:Transfection; D050495:Vesicular Inhibitory Amino Acid Transport Proteins / Q000235:genetics / Q000378:metabolism
chemical_list: D002352:Carrier Proteins; D000072233:Homer Scaffolding Proteins; C118623:Slc32a1 protein, rat; D050495:Vesicular Inhibitory Amino Acid Transport Proteins