Uncoupling the roles of synaptotagmin I as a dual Ca2+ sensor during endo- and exocytosis of synaptic vesicles

  title={Uncoupling the roles of synaptotagmin I as a dual Ca2+ sensor during endo- and exocytosis of synaptic vesicles},
  author={Jun Yao and Sung E. Kwon and Jon D. Gaffaney and F. Mark Dunning and Edwin R. Chapman},
  journal={Nature neuroscience},
  pages={243 - 249}
Synaptotagmin I (syt1) is required for normal rates of synaptic vesicle endo- and exocytosis. However, whether the kinetic defects observed during endocytosis in Syt1 knockout neurons are secondary to defective exocytosis or whether syt1 directly regulates the rate of vesicle retrieval remains unknown. To address this question, we sought to dissociate these two activities. We uncoupled the function of syt1 in exo- and endocytosis in mouse neurons either by re-targeting the protein or via… 

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Synaptotagmin I is necessary for compensatory synaptic vesicle endocytosis in vivo

It is demonstrated that Syt I is necessary for the endocytosis of synaptic vesicles that have undergone exocytotic treatment using a functional SyT I protein.

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It is shown that endocytosis is significantly impaired in the absence of SytI with the relative rates of endocytic-endocytic coupling in synapses reduced approximately 3-fold with respect to WT.

Three distinct kinetic groupings of the synaptotagmin family: candidate sensors for rapid and delayed exocytosis.

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