The trimeric complex formed between V-SNARE (VAMP) and the T-SNAREs (syntaxin and SNAP 25) after priming step is called transSNARE complex because the members of each group lie on the opposide side of the membrane, plasmamembrane side and the vesicular membrane side. Ca2+ influx through the Voltage gated Calcium Channels (VGCC) initaites the process of fusion of the synaptic vesicle in the presynaptic cell. The rise in Ca2+ leads to the activation of Protein Kinase A through rise in cAMP. Synaptotagmin, a Ca2+ sensor proetin also plays a role in the fusion process. Following fusion the members of V and T SNARES lie on the same membrane formin the cis-SNARES. The fusion of release causes the release of the neurotransmitter into the synaptic cleft.
SNARE binding activity of Docked serotonin loaded synaptic vesicle [plasma membrane]