an integral membrane protein of synaptic vesicles thought to serve as a Ca(2+) sensor in the process of vesicular trafficking and exocytosis. Calcium binding to synaptotagmin I participates in triggering neurotransmitter release at the synapse. Binds acidic phospholipids with a specificity that requires the presence of both an acidic head group and a diacyl backbone. A Ca(2+)-dependent interaction between synaptotagmin and putative receptors for activated protein kinase C has also been reported. It can bind to at least three additional proteins in a Ca(2+)-independent manner; these are neurexins, syntaxin and AP2. Note: This description may include information from UniProtKB.
Protein type: Calcium-binding; Membrane protein, integral; Vesicle