Cellular mechanisms for the biogenesis and transport of synaptic and dense-core vesicles.

The release of intercellular messengers from synaptic (SVs) and dense-core vesicles (DCVs) constitutes the primary mechanism for communication between neighboring or distant cells and organs in response to stimuli. Here we review the life span of SVs and DCVs found in the brain, neuroendocrine and exocrine tissues. These vesicles must be formed, trafficked, and their contents secreted; processes which require orchestrated actions of a great repertoire of lipids, proteins, and enzymes. For biogenesis and vesicular budding, lipids that influence curvature and aggregation of cargo are necessary for pinching off of vesicles. Vesicles travel on cytoskeletal filaments powered by motors that control the dynamics: location, speed, and directionality of movement. Regardless of mechanisms of traffic, vesicles arrive at sites of release and are docked for exocytosis, followed by membrane fusion, and release of vesicular content to exert physiological responses. Neurological disorders with pathology involving abnormal vesicular budding, trafficking, or secretion are discussed.