Model of the sequential association of undocked synaptic vesicles with different AZM macromolecules leading to docking.

<p>When a docked synaptic vesicle (<b>A</b>) fuses with the presynaptic membrane (<b>B</b>), booms (purple), spars (red), and ribs (yellow gold) remain attached to the vesicle membrane until it undergoes flattening into the presynaptic membrane (<b>C</b>). An undocked vesicle within 50 nm of the docking site on the presynaptic membrane first forms connections with booms that have dissociated from the fused vesicle (<b>C</b>) and then sequentially with dissociated spars (<b>D</b>) and ribs-pins (<b>E</b>) which direct it to the docking site on the presynaptic membrane (<b>A</b>). Pins are not included in <b>B</b>, <b>C</b> and <b>D</b> because we were unable to distinguish them from other presynaptic membrane linked macromolecules as the fused vesicles flattened.