VAMP/synaptobrevin isoforms 1 and 2 are widely and differentially expressed in nonneuronal tissues.

Abstract

Abstract. VAMP/synaptobrevin is part of the synaptic vesicle docking and fusion complex and plays a central role in neuroexocytosis. Two VAMP (vesicle-associated membrane protein) isoforms are expressed in the nervous system and are differently distributed among the specialized parts of the tissue. Here, VAMP-1 and -2 are shown to be present in all rat tissues tested, including kidney, adrenal gland, liver, pancreas, thyroid, heart, and smooth muscle. The two isoforms are differentially expressed in various tissues and their level may depend on differentiation. VAMP-1 is restricted to exocrine pancreas and to kidney tubular cells, whereas VAMP-2 is the predominant isoform present in Langerhans islets and in glomerular cells. Both isoforms show a patchy vesicular intracellular distribution in confocal microscopy. The present results provide evidence for the importance of neuronal VAMP proteins in the physiology of all cells.UKARYOTIC cells possess organized secretory pathways for the exocytosis of proteins and other molecules. These secretory routes consist of several discrete membrane compartments and of transport vesicles that shuttle between these compartments (Rothman and

Nephrin Is Critical for the Action of Insulin on Human Glomerular Podocytes

“…VAMP2 is an important vesicular SNARE that is involved in the targeting and docking of vesicles with cognate target SNARES in cells. It is predominantly involved in the docking of neurotransmitter secretary vesicles in neurones and insulin-responsive GLUT4-rich vesicles in muscle and adipocytes (42). We presume that nephrin is acting as a modifying protein in this SNARE complex in the podocyte.…”

Snake presynaptic neurotoxins with phospholipase A2 activity induce punctate swellings of neurites and exocytosis of synaptic vesicles

“…Polyclonal antibody against tubulin and phalloidin-TRITC (Sigma) were used at dilutions of 1:300 and 1:100, respectively. Polyclonal antibody against SNAP25 (produced in our laboratory against the 12 C-terminal amino acids of SNAP25) was used at a dilution of 1:300; monoclonal antibody against syntaxin (Synaptic Systems, Göttingen, Germany) was used at a dilution of 1:1000; polyclonal antibody against vesicle-attached membrane protein 2 (VAMP2) (Rossetto et al, 1996) was used at a dilution of 1:300; monoclonal antibody against synaptophysin (DAKO, Glostrup, Denmark) was used at a dilution of 1:10; monoclonal antibody against synaptotagmin 1 lumenal domain (Synaptic Systems) was used at a dilution of 1:100; polyclonal antibody against glial fibrillar acidic protein (GFAP) (DAKO) was used at a dilution of 1:1000. Fluorescein-or Texas-Red-conjugated secondary antibodies (Calbiochem, San Diego, CA, USA) were used at a working dilution of 1:100.…”

Ca2+or Sr2+Partially Rescues Synaptic Transmission in Hippocampal Cultures Treated with Botulinum Toxin A and C, But Not Tetanus Toxin

“…A mouse anti-synaptophysin monoclonal antibody (SY38, 1:20 dilution; Boehringer Mannheim, Mannheim, Germany) was applied (84 hr at 4°C) in incubation medium containing 0.4% Triton X-100, together with anti-VAM P/synaptobrevin-2 (1:100 dilution), anti-SNAP-25 (1:200 dilution), or anti-syntaxin (1:200 dilution) affinity-purified antibodies from rabbit [provided by C. Montecucco, University of Padua, Italy; for detailed description of the epitopes recognized by these antibodies, see Rossetto et al (1996) and Williamson et al (1996)]. Cultures were washed in incubation medium, followed by application of a biotinylated anti-rabbit antibody (1:200 dilution; 3 hr at 22°C), and then washed again before using an anti-mouse antibody (1:150 dilution; 20 min at 22°C) directly conjugated to FI TC to reveal the anti-synaptophysin antibodies.…”