Learn More
While there is compelling evidence that the synaptic vesicle protein synaptotagmin serves as the major Ca2+ sensor for regulated exocytosis, it is not known how Ca2+ binding initiates membrane fusion. Here we report that Ca2+ increases the affinity, by approximately 2 orders of magnitude, between synaptotagmin and syntaxin 1, a component of the synaptic(More)
Synaptotagmin serves as the major Ca2+ sensor for regulated exocytosis from neurons. While the mechanism by which synaptotagmin regulates membrane fusion remains unknown, studies using Drosophila indicate that the molecule functions as a multimeric complex and that its second C2 domain is essential for efficient excitation-secretion coupling. Here we(More)
The membrane proteins SNAP-25, syntaxin, and synaptobrevin (vesicle-associated membrane protein) have recently been implicated as central elements of an exocytotic membrane fusion complex in neurons. Here we report that SNAP-25 binds directly to both syntaxin and synaptobrevin. The SNAP-25-binding domain of syntaxin lies between residues 199 and 243, within(More)
Synaptotagmin I is localized to synaptic vesicles where it functions in the calcium-triggered release of neurotransmitters. Here we demonstrate that synaptotagmin I covalently incorporated [3H]palmitate after metabolic labelling of PC-12 cells and rat brain synaptosomes. Labeling was localized to a tryptic fragment that contains a cluster of cysteine(More)
We describe the development of a new secretory production system for the enhanced production of a single-chain variable fragment (scFv) against the anthrax toxin in Corynebacterium glutamicum. For efficient secretory production of the antibody fragment, the following components were examined: (1) signal peptides, (2) codon usage of antibody fragment, (3)(More)
Syncollin is a pancreatic zymogen granule protein that was isolated through its ability to bind to syntaxin. Here we show that syncollin has a cleavable signal sequence and can be removed from granule membranes by washing with sodium carbonate. When membranes were subjected to Triton X-114 partitioning, syncollin was found predominantly in the aqueous(More)
by BoNT/A (residues 1 to 197) were reconstituted into vesicles (with 15% PS). As a control, a truncated version of SNAP-25 that mimics cleavage by BoNT/E (corresponding to residues 1 to 180), was tested in parallel [this cleavage event results in a more profound block of exocytosis (13)]. Fusion was abolished by the " BoNT/E " truncation (Fig. 4B). In(More)
  • 1