The control of release probability at nerve terminals.

Exocytosis is a fundamental membrane fusion process by which the soluble or membrane-associated cargoes of a secretory vesicle are delivered to the extracellular milieu or the cell surface. While essential for all organs, the brain relies on a specialized form of exocytosis to mediate information flow throughout its vast circuitry. Neurotransmitter-laden synaptic vesicles fuse with the plasma membrane on cue with astonishing speed in a probabilistic process that is both tightly regulated and capable of a fascinating array of plasticities. Here, we examine progress in the molecular understanding of synaptic vesicle fusion and its control.