Syndapin is dispensable for synaptic vesicle endocytosis at the Drosophila larval neuromuscular junction

Mol Cell Neurosci. 2009 Feb;40(2):234-41. doi: 10.1016/j.mcn.2008.10.011. Epub 2008 Nov 12.

Abstract

Syndapin is a conserved dynamin-binding protein, with predicted function in synaptic-vesicle endocytosis. Here, we combine genetic mutational analysis with in vivo cell biological assays to ask whether Drosophila syndapin (Synd) is an essential component of synaptic-vesicle recycling. The only isoform of Drosophila syndapin (synd) is broadly expressed and at high levels in the nervous system. synd mutants are late-larval lethals, but fertile adult "escapers" frequently emerge. Contrary to expectation, we report that the Synd protein is predominantly postsynaptic, undetectable at presynaptic varicosities at Drosophila third-instar larval neuromuscular junctions. Electrophysiological and synaptopHluorin imaging in control, synd-deficient or synd-overexpressing motor neurons reveals that synd is dispensable for synaptic-vesicle endocytosis. Our work in Drosophila leads to the suggestion that syndapin may not be a general or essential component in dynamin-dependent synaptic-vesicle endocytosis.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Alleles
  • Animals
  • Animals, Genetically Modified
  • Carrier Proteins / genetics
  • Carrier Proteins / metabolism*
  • Drosophila Proteins / genetics
  • Drosophila Proteins / metabolism*
  • Drosophila melanogaster* / anatomy & histology
  • Drosophila melanogaster* / physiology
  • Dynamins / genetics
  • Dynamins / metabolism
  • Larva* / anatomy & histology
  • Larva* / physiology
  • Membrane Potentials / physiology
  • Nerve Tissue Proteins / genetics
  • Nerve Tissue Proteins / metabolism*
  • Neuromuscular Junction / physiology*
  • Protein Isoforms / genetics
  • Protein Isoforms / metabolism
  • Synaptic Transmission / physiology
  • Synaptic Vesicles / metabolism*

Substances

  • Carrier Proteins
  • Drosophila Proteins
  • Nerve Tissue Proteins
  • Protein Isoforms
  • Synd protein, Drosophila
  • Dynamins