title: BAR-SH3 sorting nexins are conserved interacting proteins of Nervous wreck that organize synapses and promote neurotransmission.
abstract: Nervous wreck (Nwk) is a conserved F-BAR protein that attenuates synaptic growth and promotes synaptic function in Drosophila. In an effort to understand how Nwk carries out its dual roles, we isolated interacting proteins using mass spectrometry. We report a conserved interaction between Nwk proteins and BAR-SH3 sorting nexins, a family of membrane-binding proteins implicated in diverse intracellular trafficking processes. In mammalian cells, BAR-SH3 sorting nexins induce plasma membrane tubules that localize NWK2, consistent with a possible functional interaction during the early stages of endocytic trafficking. To study the role of BAR-SH3 sorting nexins in vivo, we took advantage of the lack of genetic redundancy in Drosophila and employed CRISPR-based genome engineering to generate null and endogenously tagged alleles of SH3PX1. SH3PX1 localizes to neuromuscular junctions where it regulates synaptic ultrastructure, but not synapse number. Consistently, neurotransmitter release was significantly diminished in SH3PX1 mutants. Double-mutant and tissue-specific-rescue experiments indicate that SH3PX1 promotes neurotransmitter release presynaptically, at least in part through functional interactions with Nwk, and might act to distinguish the roles of Nwk in regulating synaptic growth and function.
authors.affiliation: Laboratory of Cell and Molecular Biology, University of Wisconsin-Madison, Madison, WI 53706, USA.
authors.forename: Fiona P
authors.initials: FP
authors.lastname: Ukken
authors.affiliation: Cell and Molecular Biology Training Program, University of Wisconsin-Madison, Madison, WI 53706, USA.
authors.forename: Joseph J
authors.initials: JJ
authors.lastname: Bruckner
authors.affiliation: Laboratory of Cell and Molecular Biology, University of Wisconsin-Madison, Madison, WI 53706, USA.
authors.forename: Kurt L
authors.initials: KL
authors.lastname: Weir
authors.affiliation: Laboratory of Cell and Molecular Biology, University of Wisconsin-Madison, Madison, WI 53706, USA.
authors.forename: Sarah J
authors.initials: SJ
authors.lastname: Hope
authors.affiliation: Laboratory of Cell and Molecular Biology, University of Wisconsin-Madison, Madison, WI 53706, USA.
authors.forename: Samantha L
authors.initials: SL
authors.lastname: Sison
authors.affiliation: Laboratory of Cell and Molecular Biology, University of Wisconsin-Madison, Madison, WI 53706, USA.
authors.forename: Ryan M
authors.initials: RM
authors.lastname: Birschbach
authors.affiliation: Cellular Biology and Anatomy, Georgia Regents University, Augusta, GA 30912, USA.
authors.forename: Lawrence
authors.initials: L
authors.lastname: Hicks
authors.affiliation: Neuroscience Training Program, University of Wisconsin-Madison, Madison, WI 53705, USA.
authors.forename: Kendra L
authors.initials: KL
authors.lastname: Taylor
authors.affiliation: Neuroscience Training Program, University of Wisconsin-Madison, Madison, WI 53705, USA Department of Neuroscience, University of Wisconsin-Madison, Madison, WI 53705, USA.
authors.forename: Erik W
authors.initials: EW
authors.lastname: Dent
authors.affiliation: Cellular Biology and Anatomy, Georgia Regents University, Augusta, GA 30912, USA.
authors.forename: Graydon B
authors.initials: GB
authors.lastname: Gonsalvez
authors.affiliation: Laboratory of Cell and Molecular Biology, University of Wisconsin-Madison, Madison, WI 53706, USA Cell and Molecular Biology Training Program, University of Wisconsin-Madison, Madison, WI 53706, USA Laboratory of Genetics, University of Wisconsin-Madison, Madison, WI 53706, USA oconnorgiles@wisc.edu.
authors.forename: Kate M
authors.initials: KM
authors.lastname: O'Connor-Giles
mesh_terms: D000818:Animals; D002352:Carrier Proteins / Q000378:metabolism; D002460:Cell Line; D002540:Cerebral Cortex / Q000166:cytology; D017124:Conserved Sequence; D029721:Drosophila Proteins / Q000378:metabolism*; D004331:Drosophila melanogaster / Q000378:metabolism*; D047908:Intracellular Signaling Peptides and Proteins; D051379:Mice; D009154:Mutation / Q000235:genetics; D009419:Nerve Tissue Proteins / Q000378:metabolism*; D055495:Neurogenesis; D009469:Neuromuscular Junction / Q000378:metabolism; D009474:Neurons / Q000378:metabolism; D018377:Neurotransmitter Agents / Q000378:metabolism; D011485:Protein Binding; D021381:Protein Transport; D058305:Sorting Nexins / Q000378:metabolism*; D013569:Synapses / Q000378:metabolism* / Q000648:ultrastructure; D009435:Synaptic Transmission
chemical_list: D002352:Carrier Proteins; D029721:Drosophila Proteins; D047908:Intracellular Signaling Peptides and Proteins; D009419:Nerve Tissue Proteins; D018377:Neurotransmitter Agents; C498519:SH3PX1 protein, Drosophila; D058305:Sorting Nexins; C483010:nwk protein, Drosophila
keywords: Drosophila neuromuscular junction; Nervous wreck; Neurotransmission; Sorting nexin; Synaptogenesis