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Tracking SNARE complex formation in live endocrine cells.

Seong J An·Wolfhard Almers
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Abstract

Syntaxin, synaptosome-associated protein of 25 kD (SNAP25), and vesicle-associated membrane protein/synaptobrevin are collectively called SNAP receptor (SNARE) proteins, and they catalyze neuronal exocytosis by forming a "core complex." The steps in core complex formation are unknown. Here, we monitored SNARE complex formation in vivo with the use of a fluorescent version of SNAP25. In PC12 cells, we found evidence for a syntaxin-SNAP25 complex that formed with high affinity, required only the amino-terminal SNARE motif of SNAP25, tolerated a mutation that blocks formation of other syntaxin-SNAP25 complexes, and assembled reversibly when Ca2+ entered cells during depolarization. The complex may represent a precursor to the core complex formed during a Ca2+-dependent priming step of exocytosis.

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Adrenal MedullaAnimalsBacterial ProteinsCell LineFluorescence Resonance Energy TransferGreen Fluorescent ProteinsHumansLuminescent ProteinsMembrane ProteinsNerve Tissue ProteinsPC12 CellsQa-SNARE ProteinsRatsRecombinant Fusion ProteinsSNARE ProteinsSynaptosomal-Associated Protein 25Vesicular Transport ProteinsJournal ArticleResearch Support, U.S. Gov't, P.H.S.

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Seong J An, Wolfhard Almers. 2004-11-05. Tracking SNARE complex formation in live endocrine cells.. https://doi.org/10.1126/science.1102559

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