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Similarly, nerve cells seem to package key components of synapses—the specialized structures that allow the cells to communicate with one another—and collectively ship the material to points where these complexes take shape. "Everything is bundled [and transported] together.
The final stage of construction probably happens at the site of cell-cell contact," says Stephen J. Smith of Stanford University. This new view of synapse assembly has emerged from efforts to study the cellular connections as they form—a phenomenon challenging to observe. In their latest work, Smith and his Stanford colleagues Susanne E. Ahmari and JoAnn Buchanan were following a synaptic protein called VAMP. This molecule helps form vesicles, sacs containing the chemicals that on