Synaptotagmin I (SYT1)

The synaptotagmins are integral membrane proteins of synaptic vesicles thought to serve as Ca(2 ) sensors in the process of vesicular trafficking and exocytosis. Calcium binding to synaptotagmin I participates in triggering neurotransmitter release at the synapse.

synaptotagmin, a highly conserved synaptic vesicle protein, binds calcium at physiologic concentrations in a complex with negatively charged phospholipids. This binding is specific for calcium and involves the cytoplasmic domain of synaptotagmin. Calcium binding is dependent on the intact oligomeric structure of synaptotagmin; it is abolished by proteolytic cleavage at a single site.