Figure 5.

Model for the effects of GST–SYP on the vesicle pool and on neurotransmitter release. In control synapses stimulated at high-frequency (Upper), many vesicles are recycled by rapid endocytosis (RE) and some collapse into the membrane and are retrieved by clathrin-mediated endocytosis (CME). When rapid endocytosis is blocked (Lower), more of the fused SVs are forced to recycle via CCVs. Because the clathrin pathway is slower, the result is a temporary redistribution of SV membrane from the active zone to the clathrin-dependent recycling pathway. The depletion of vesicles at the active zone results in a decrease in transmitter release.