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: Vesicle protein; Calcium-binding protein; Membrane protein, integral
Chromosomal Location of Human Ortholog: 12cen-q21
Cellular Component: presynaptic membrane; synaptic vesicle; neuron projection; synaptic vesicle membrane; plasma membrane; integral to membrane; excitatory synapse; cell junction
Molecular Function: protein C-terminus binding; identical protein binding; clathrin binding; calcium-dependent phospholipid binding; transporter activity; calcium ion binding; calcium-dependent protein binding; calmodulin binding; phosphatidylinositol-4,5-bisphosphate binding; protein binding; low-density lipoprotein receptor binding; phosphatidylserine binding; syntaxin-1 binding; phospholipid binding; phosphatidylinositol binding
Biological Process: regulation of exocytosis; positive regulation of calcium ion-dependent exocytosis; synaptic transmission; synaptic vesicle exocytosis; vesicle docking; glutamate secretion; neurotransmitter secretion; positive regulation of vesicle fusion; detection of calcium ion; protein homooligomerization
SS: The number of records in which this modification site was determined using site-specific methods. SS methods include amino acid sequencing, site-directed mutagenesis, modification site-specific antibodies, specific MS strategies, etc.