Calcium-Dependent Exocytosis, Biophysical Models of
Calcium-dependent exocytosis is the biochemically controlled fusion of the bilipid secretory vesicle membrane with the bilipid cell membrane, triggered by the binding of several Ca2+ ions to control proteins such as synaptotagmins anchored at the interface between these two membranes. Exocytosis results in the release of vesicle contents into the extracellular space, namely, the release of neurotransmitter into the synaptic cleft in the case of neuronal synapses and neuromuscular junctions or the secretion of hormone into the bloodstream in the case of endocrine cells. Exocytosis also allows the transmembrane proteins contained in the vesicle membrane to be incorporated into the cell membrane, although such membrane protein trafficking is more characteristic of Ca2+-independent, constitutive exocytosis.
In synapses, neuromuscular junctions, and endocrine cells, fast Ca2+-triggered exocytosis of...
KeywordsVesicle Fusion Ribbon Synapse Vesicle Release Vesicle Pool Vesicle Priming
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