How It’s Made: The Synapse
Figure 4
In developing axons, synaptic vesicle and active zone proteins are delivered to developing presynaptic terminals via distinct precursor organelles. Synaptic vesicle protein transport vesicles (STVs) (red) carry a variety of synaptic vesicle proteins and have morphologies ranging from tubulovesicular structures to clusters of small clear vesicles that resemble synaptic vesicles. Piccolo-bassoon transport vesicles (PTVs) (green) carry several active zone proteins and have been described as dense-core vesicles. It is not clear which cues recruit these transport intermediates to developing synapses.
