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Synaptotagmin 7 splice variants differentially regulate synaptic vesicle recycling.

Tuhin Virmani·Weiping Han·Xinran Liu·Thomas C Südhof·Ege T Kavalali
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Abstract

The speed of synaptic vesicle recycling determines the efficacy of neurotransmission during repetitive stimulation. Synaptotagmins are synaptic C(2)-domain proteins that are involved in exocytosis, but have also been linked to endocytosis. We now demonstrate that upon expression in transfected neurons, a short splice variant of synaptotagmin 7 that lacks C(2)-domains accelerates endocytic recycling of synaptic vesicles, whereas a longer splice variant that contains C(2)-domains decelerates recycling. These results suggest that alternative splicing of synaptotagmin 7 acts as a molecular switch, which targets vesicles to fast and slow recycling pathways.

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Alternative SplicingAnimalsAnimals, NewbornCalcium-Binding ProteinsCells, CulturedGenetic VariationHippocampusMembrane GlycoproteinsMembrane PotentialsMicroscopy, ElectronNerve Tissue ProteinsNeuronsRatsRats, Sprague-DawleyReceptors, Cell SurfaceRecombinant ProteinsSynapsesSynaptic VesiclesSynaptotagminsJournal ArticleResearch Support, Non-U.S. Gov't

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Tuhin Virmani, Weiping Han, Xinran Liu, Thomas C Südhof, Ege T Kavalali. 2003-10-15. Synaptotagmin 7 splice variants differentially regulate synaptic vesicle recycling.. https://doi.org/10.1093/emboj%2Fcdg514

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