Defective recycling of synaptic vesicles in synaptotagmin mutants of Caenorhabditis elegans

Nature. 1995 Nov 9;378(6553):196-9. doi: 10.1038/378196a0.


Synaptotagmin, an integral membrane protein of the synaptic vesicle, binds calcium and interacts with proteins of the plasma membrane. These observations suggest several possible functions for synaptotagmin in synaptic vesicle dynamics: it could facilitate exocytosis by promoting calcium-dependent fusion, inhibit exocytosis by preventing fusion, or facilitate endocytosis of synaptic vesicles from the plasma membrane by acting as a receptor for the endocytotic proteins of the clathrin AP2 complex. Here we show that synaptic vesicles are depleted at synaptic terminals in synaptotagmin mutants of the nematode Caenorhabditis elegans. This depletion is not caused by a defect in transport or by increased synaptic vesicle release, but rather by a defect in retrieval or synaptic vesicles from the plasma membrane. Thus we propose that, as well as being involved in exocytosis, synaptotagmin functions in vesicular recycling.

Publication types

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

MeSH terms

  • Aldicarb / pharmacology
  • Animals
  • Caenorhabditis elegans / genetics
  • Caenorhabditis elegans / metabolism*
  • Calcium-Binding Proteins*
  • Cholinesterase Inhibitors / pharmacology
  • Exocytosis
  • GTP-Binding Proteins / metabolism
  • Membrane Glycoproteins / genetics
  • Membrane Glycoproteins / metabolism*
  • Mutation
  • Nerve Tissue Proteins / genetics
  • Nerve Tissue Proteins / metabolism*
  • Synaptic Membranes / metabolism
  • Synaptic Vesicles / metabolism*
  • Synaptotagmins
  • rab3 GTP-Binding Proteins


  • Calcium-Binding Proteins
  • Cholinesterase Inhibitors
  • Membrane Glycoproteins
  • Nerve Tissue Proteins
  • Synaptotagmins
  • Aldicarb
  • GTP-Binding Proteins
  • rab3 GTP-Binding Proteins