Molecular circuitry of endocytosis at nerve terminals.

Presynaptic terminals are specialized compartments of neurons responsible for converting electrical signals into secreted chemicals. This self-renewing process of chemical synaptic transmission is accomplished by the calcium-triggered fusion of neurotransmitter-containing vesicles with the plasma membrane and subsequent retrieval and recycling of vesicle components. Whereas the release of neurotransmitters has been studied for over 50 years, the process of synaptic vesicle endocytosis has remained much more elusive. The advent of imaging techniques suited to monitor membrane retrieval at presynaptic terminals and the discovery of the molecules that orchestrate endocytosis have revolutionized our understanding of this critical trafficking event.