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PubMed · 7553862

Complexins: cytosolic proteins that regulate SNAP receptor function.

H T McMahon·M Missler·C Li·T C Südhof
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Abstract

A family of proteins called complexins was discovered that compete with alpha-SNAP, but not synaptotagmin, for SNAP receptor binding. Complexins I and II are highly homologous hydrophilic proteins that are tightly conserved, with 100% identity among mouse, rat, and human complexin II. They are enriched in neurons where they colocalize with syntaxin and SNAP-25; in addition, complexin II is expressed ubiquitously at low levels. Complexins bind weakly to syntaxin alone and not at all to synaptobrevin and SNAP-25, but strongly to the SNAP receptor-core complex composed of these three molecules. They compete with alpha-SNAP for binding to the core complex but not with other interacting molecules, including synaptotagmin I, suggesting that the complexins regulate the sequential interactions of alpha-SNAP and synaptotagmins with the SNAP receptor during exocytosis.

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Adaptor Proteins, Vesicular TransportAmino Acid SequenceAnimalsBrain ChemistryCalciumCalcium-Binding ProteinsCarrier ProteinsCytosolExocytosisGene ExpressionHippocampusHumansMacromolecular SubstancesMembrane FusionMembrane GlycoproteinsMembrane ProteinsMiceMolecular Sequence DataNerve Tissue ProteinsNeuronsR-SNARE ProteinsRatsRecombinant Fusion ProteinsSNARE ProteinsSequence AlignmentSequence Homology, Amino AcidSoluble N-Ethylmaleimide-Sensitive Factor Attachment ProteinsSpecies SpecificitySynaptic VesiclesSynaptosomal-Associated Protein 25Synaptotagmin ISynaptotagminsVesicular Transport ProteinsComparative StudyJournal ArticleResearch Support, Non-U.S. Gov't

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H T McMahon, M Missler, C Li, T C Südhof. 1995-10-06. Complexins: cytosolic proteins that regulate SNAP receptor function.. https://doi.org/10.1016/0092-8674(95)90239-2

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