Please use this identifier to cite or link to this item:
https://hdl.handle.net/2445/25209
Title: | The t-SNAREs syntaxin 1 and SNAP-25 are present on organelles that participate in synaptic vesicle recycling |
Author: | Walch-Solimena, Christiane Blasi Cabús, Joan Edelmann, Lambert Chapmann, Edwin R. Fischer von Mollard, Gabriele Jahn, Reinhard |
Keywords: | Neurones Sinapsi Neurotransmissió Interacció cel·lular Neurons Synapses Neural transmission Cell interaction |
Issue Date: | 15-Feb-1995 |
Publisher: | Rockefeller University Press |
Abstract: | Syntaxin 1 and synaptosome-associated protein of 25 kD (SNAP-25) are neuronal plasmalemma proteins that appear to be essential for exocytosis of synaptic vesicles (SVs). Both proteins form a complex with synaptobrevin, an intrinsic membrane protein of SVs. This binding is thought to be responsible for vesicle docking and apparently precedes membrane fusion. According to the current concept, syntaxin 1 and SNAP-25 are members of larger protein families, collectively designated as target-SNAP receptors (t-SNAREs), whose specific localization to subcellular membranes define where transport vesicles bind and fuse. Here we demonstrate that major pools of syntaxin 1 and SNAP-25 recycle with SVs. Both proteins cofractionate with SVs and clathrin-coated vesicles upon subcellular fractionation. Using recombinant proteins as standards for quantitation, we found that syntaxin 1 and SNAP-25 each comprise approximately 3% of the total protein in highly purified SVs. Thus, both proteins are significant components of SVs although less abundant than synaptobrevin (8.7% of the total protein). Immunoisolation of vesicles using synaptophysin and syntaxin specific antibodies revealed that most SVs contain syntaxin 1. The widespread distribution of both syntaxin 1 and SNAP-25 on SVs was further confirmed by immunogold electron microscopy. Botulinum neurotoxin C1, a toxin that blocks exocytosis by proteolyzing syntaxin 1, preferentially cleaves vesicular syntaxin 1. We conclude that t-SNAREs participate in SV recycling in what may be functionally distinct forms. |
Note: | Reproducció digital del document publicat a: http://dx.doi.org/10.1083/jcb.128.4.637 |
It is part of: | Journal of Cell Biology, 1995, vol. 128, núm. 4, p. 637-645 |
URI: | https://hdl.handle.net/2445/25209 |
Related resource: | http://dx.doi.org/10.1083/jcb.128.4.637 |
ISSN: | 0021-9525 |
Appears in Collections: | Articles publicats en revistes (Patologia i Terapèutica Experimental) |
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