Tweek, an evolutionarily conserved protein, is required for synaptic vesicle recycling

Neuron. 2009 Jul 30;63(2):203-15. doi: 10.1016/j.neuron.2009.06.017.


Synaptic vesicle endocytosis is critical for maintaining synaptic communication during intense stimulation. Here we describe Tweek, a conserved protein that is required for synaptic vesicle recycling. tweek mutants show reduced FM1-43 uptake, cannot maintain release during intense stimulation, and harbor larger than normal synaptic vesicles, implicating it in vesicle recycling at the synapse. Interestingly, the levels of a fluorescent PI(4,5)P(2) reporter are reduced at tweek mutant synapses, and the probe is aberrantly localized during stimulation. In addition, various endocytic adaptors known to bind PI(4,5)P(2) are mislocalized and the defects in FM1-43 dye uptake and adaptor localization are partially suppressed by removing one copy of the phosphoinositide phosphatase synaptojanin, suggesting a role for Tweek in maintaining proper phosphoinositide levels at synapses. Our data implicate Tweek in regulating synaptic vesicle recycling via an action mediated at least in part by the regulation of PI(4,5)P(2) levels or availability at the synapse.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Blotting, Western
  • DNA, Complementary
  • Diptera
  • Drosophila Proteins / physiology*
  • Endocytosis / genetics
  • Endocytosis / physiology*
  • Eye Abnormalities / genetics
  • Immunohistochemistry
  • Microscopy, Electron, Transmission
  • Molecular Sequence Data
  • Mutation
  • Nerve Tissue Proteins / physiology*
  • Neurons / metabolism*
  • Neurons / ultrastructure
  • Phosphatidylinositol Phosphates / metabolism*
  • Pyridinium Compounds / metabolism
  • Quaternary Ammonium Compounds / metabolism
  • Reverse Transcriptase Polymerase Chain Reaction
  • Synapses / genetics
  • Synapses / metabolism*
  • Synapses / ultrastructure
  • Synaptic Transmission / genetics
  • Synaptic Transmission / physiology*
  • Synaptic Vesicles / genetics
  • Synaptic Vesicles / metabolism*
  • Synaptic Vesicles / ultrastructure


  • DNA, Complementary
  • Drosophila Proteins
  • FM1 43
  • Nerve Tissue Proteins
  • Phosphatidylinositol Phosphates
  • Pyridinium Compounds
  • Quaternary Ammonium Compounds