title: Syndapin is dispensable for synaptic vesicle endocytosis at the Drosophila larval neuromuscular junction.
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.
authors.affiliation: Smurfit Institute of Genetics and Trinity College Institute of Neuroscience, Lloyd Building, University of Dublin, Trinity College, Dublin 2, Ireland. kumarv@tcd.ie
authors.forename: Vimlesh
authors.initials: V
authors.lastname: Kumar
authors.forename: Suneel Reddy
authors.initials: SR
authors.lastname: Alla
authors.forename: K S
authors.initials: KS
authors.lastname: Krishnan
authors.forename: Mani
authors.initials: M
authors.lastname: Ramaswami
mesh_terms: D000483:Alleles; D000818:Animals; D030801:Animals, Genetically Modified; D002352:Carrier Proteins / Q000235:genetics / Q000378:metabolism*; D029721:Drosophila Proteins / Q000235:genetics / Q000378:metabolism*; D004331:Drosophila melanogaster / Q000033:anatomy & histology / Q000502:physiology; D034281:Dynamins / Q000235:genetics / Q000378:metabolism; D007814:Larva / Q000033:anatomy & histology / Q000502:physiology; D008564:Membrane Potentials / Q000502:physiology; D009419:Nerve Tissue Proteins / Q000235:genetics / Q000378:metabolism*; D009469:Neuromuscular Junction / Q000502:physiology*; D020033:Protein Isoforms / Q000235:genetics / Q000378:metabolism; D009435:Synaptic Transmission / Q000502:physiology; D013572:Synaptic Vesicles / Q000378:metabolism*
chemical_list: D002352:Carrier Proteins; D029721:Drosophila Proteins; D009419:Nerve Tissue Proteins; D020033:Protein Isoforms; C540273:Synd protein, Drosophila; D034281:Dynamins