title: Mutations in Wnt2 alter presynaptic motor neuron morphology and presynaptic protein localization at the Drosophila neuromuscular junction.
abstract: Wnt proteins are secreted proteins involved in a number of developmental processes including neural development and synaptogenesis. We sought to determine the role of the Drosophila Wnt7b ortholog, Wnt2, using the neuromuscular junction (NMJ). Mutations in wnt2 produce an increase in the number of presynaptic branches and a reduction in immunolabeling of the active zone proteins, Bruchpilot and synaptobrevin, at the NMJ. There was no change, however, in immunolabeling for the presynaptic proteins cysteine-string protein (CSP) and synaptotagmin, nor the postsynaptic proteins GluRIIA and DLG at the NMJ. Consistent with the presynaptic defects, wnt2 mutants exhibit approximately a 50% reduction in evoked excitatory junctional currents. Rescue, RNAi, and tissue-specific qRT-PCR experiments indicate that Wnt2 is expressed by the postsynaptic cell where it may serve as a retrograde signal that regulates presynaptic morphology and the localization of presynaptic proteins.
authors.affiliation: Department of Biological Sciences, Southern Illinois University Edwardsville, Edwardsville, Illinois, United States of America. fliebl@siue.edu
authors.forename: Faith L W
authors.initials: FL
authors.lastname: Liebl
authors.forename: Cassandra
authors.initials: C
authors.lastname: McKeown
authors.forename: Ying
authors.initials: Y
authors.lastname: Yao
authors.forename: Huey K
authors.initials: HK
authors.lastname: Hing
mesh_terms: D000818:Animals; D004330:Drosophila / Q000235:genetics / Q000378:metabolism*; D029721:Drosophila Proteins / Q000235:genetics* / Q000378:metabolism; D009046:Motor Neurons / Q000166:cytology* / Q000378:metabolism; D009154:Mutation; D009469:Neuromuscular Junction / Q000235:genetics / Q000378:metabolism*; D021381:Protein Transport; D013569:Synapses / Q000235:genetics / Q000378:metabolism*; D009435:Synaptic Transmission; D051154:Wnt2 Protein / Q000235:genetics* / Q000378:metabolism
chemical_list: D029721:Drosophila Proteins; D051154:Wnt2 Protein