Inhibition of neurotransmitter release by C2-domain peptides implicates synaptotagmin in exocytosis.


Journal Article

Neurotransmitter release is triggered by Ca2+ ions binding to an unknown Ca2+ receptor within presynaptic terminals. Synaptotagmin, a Ca2(+)-binding protein of synaptic and other secretory vesicles, has been proposed to mediate vesicle-plasma membrane interactions during neurotransmitter release. Here we test this hypothesis using the giant synapse of the squid Loligo pealei, which because of its unusually large size and well established physiology is uniquely suited for dissecting presynaptic events. We find that injection of peptides from the C2 domains of synaptotagmin into squid giant presynaptic terminals rapidly and reversibly inhibits neurotransmitter release. Our data are consistent with these peptides competitively blocking release after synaptic vesicle docking and indicate that Ca2+ probably initiates neurotransmitter release by regulating the interaction of synaptotagmin with an acceptor protein.

Full Text

Cited Authors

  • Bommert, K; Charlton, MP; DeBello, WM; Chin, GJ; Betz, H; Augustine, GJ

Published Date

  • May 1993

Published In

Volume / Issue

  • 363 / 6425

Start / End Page

  • 163 - 165

PubMed ID

  • 8097867

Pubmed Central ID

  • 8097867

Electronic International Standard Serial Number (EISSN)

  • 1476-4687

International Standard Serial Number (ISSN)

  • 0028-0836

Digital Object Identifier (DOI)

  • 10.1038/363163a0


  • eng