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PubMed · 11580898

A trimeric protein complex functions as a synaptic chaperone machine.

S Tobaben·P Thakur·R Fernández-Chacón·T C Südhof·J Rettig·B Stahl
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Abstract

We identify a chaperone complex composed of (1) the synaptic vesicle cysteine string protein (CSP), thought to function in neurotransmitter release, (2) the ubiquitous heat-shock protein cognate Hsc70, and (3) the SGT protein containing three tandem tetratricopeptide repeats. These three proteins interact with each other to form a stable trimeric complex that is located on the synaptic vesicle surface, and is disrupted in CSP knockout mice. The CSP/SGT/Hsc70 complex functions as an ATP-dependent chaperone that reactivates a denatured substrate. SGT overexpression in cultured neurons inhibits neurotransmitter release, suggesting that the CSP/SGT/Hsc70 complex is important for maintenance of a normal synapse. Taken together, our results identify a novel trimeric complex that functions as a synapse-specific chaperone machine.

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Adenosine TriphosphateAnimalsBrain ChemistryCarrier ProteinsCells, CulturedExocytosisHSC70 Heat-Shock ProteinsHSP40 Heat-Shock ProteinsHSP70 Heat-Shock ProteinsHippocampusMacromolecular SubstancesMaleMembrane ProteinsMiceMice, KnockoutModels, BiologicalMolecular ChaperonesNerve Tissue ProteinsNeurotransmitter AgentsProtein BindingProtein FoldingProteinsRatsRats, WistarSynaptic TransmissionSynaptic VesiclesTwo-Hybrid System TechniquesJournal ArticleResearch Support, Non-U.S. Gov't

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S Tobaben, P Thakur, R Fernández-Chacón, T C Südhof, J Rettig, B Stahl. 2001-09-27. A trimeric protein complex functions as a synaptic chaperone machine.. https://doi.org/10.1016/s0896-6273(01)00427-5

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