Synaptotagmin I, a Ca2+ sensor for neurotransmitter release

Trends Neurosci. 2003 Aug;26(8):413-22. doi: 10.1016/S0166-2236(03)00195-4.


The discovery that Ca(2+) triggers rapid neurotransmitter release has prompted the search for the Ca(2+) sensor. There is now general agreement that the vesicle-associated Ca(2+)-binding protein, synaptotagmin I, is required for the tight temporal coupling between Ca(2+) influx and synaptic vesicle fusion. However, the precise mechanism of Ca(2+)-sensing by synaptotagmin I is still under debate despite intensive investigation using genetic, biochemical and electrophysiological tools. Here, we discuss many of the genetic manipulations from the past few years that have shed light on the Ca(2+)-sensing function of synaptotagmin I. We also present our view as to how the Ca(2+) signal is translated rapidly into membrane fusion at fast chemical synapses.

Publication types

  • Research Support, Non-U.S. Gov't
  • Review

MeSH terms

  • Animals
  • Caenorhabditis elegans
  • Calcium Signaling / physiology*
  • Calcium-Binding Proteins / physiology*
  • Drosophila
  • Exocytosis / physiology
  • Membrane Glycoproteins / physiology*
  • Mice
  • Models, Neurological
  • Nerve Tissue Proteins / physiology*
  • Neurotransmitter Agents / metabolism*
  • Receptors, Cell Surface / physiology
  • Synaptic Transmission / physiology*
  • Synaptotagmin I
  • Synaptotagmins


  • Calcium-Binding Proteins
  • Membrane Glycoproteins
  • Nerve Tissue Proteins
  • Neurotransmitter Agents
  • Receptors, Cell Surface
  • Synaptotagmin I
  • Syt1 protein, mouse
  • Synaptotagmins