Abstract
In synaptic transmission, vesicles are proposed to dock at presynaptic active zones by the association of synaptobrevin (v-SNARE) with syntaxin (t-SNARE). We test this hypothesis in Drosophila strains lacking neural synaptobrevin (n-synaptobrevin) or syntaxin. We showed previously that loss of either protein completely blocks synaptic transmission. Here, we attempt to establish the level of this blockade. Ultrastructurally, vesicles are still targeted to the presynaptic membrane and dock normally at specialized release sites. These vesicles are mature and functional since spontaneous vesicle fusion persists in the absence of n-synaptobrevin and since vesicle fusion is triggered by hyperosmotic saline in the absence of syntaxin. We conclude that the SNARE hypothesis cannot fully explain the role of these proteins in synaptic transmission. Instead, both proteins play distinct roles downstream of docking.
| Original language | English |
|---|---|
| Pages (from-to) | 663-73 |
| Number of pages | 11 |
| Journal | Neuron |
| Volume | 15 |
| Issue number | 3 |
| Publication status | Published - 1995 |
Keywords
- Animals
- Animals, Genetically Modified
- Binding Sites
- Black Widow Spider
- Calcium
- Drosophila
- Membrane Fusion
- Membrane Proteins
- Mutation
- Nerve Tissue Proteins
- Qa-SNARE Proteins
- R-SNARE Proteins
- Spider Venoms
- Synapses
- Synaptic Transmission
- Synaptic Vesicles