title: Bi-directional signaling by Semaphorin 1a during central synapse formation in Drosophila.
abstract: Semaphorins have been intensively studied for their role in dendritic and axonal pathfinding, but less is known about their potential role in synapse formation. In the adult giant fiber (GF) system of fruit flies (Drosophila melanogaster), we show that transmembrane Semaphorin 1a (Sema-1a) is involved in synapse formation in addition to its role in guidance during pathfinding. Cell-autonomous rescue experiments showed that Sema-1a is involved in assembly of a central synapse and that it is required both pre- and postsynaptically. We also found that pre- but not postsynaptic gain-of-function Sema-1a was able to disrupt the GF-motor neuron synapse and that the phenotype depended on a proline-rich intracellular domain that contains a putative Enabled binding site. We suggest that transmembrane Sema-1a is part of a bi-directional signaling system that leads to the formation of the GF synapse and possibly acts as both a ligand and a receptor.
authors.affiliation: University of Massachusetts, Department of Biology, Morrill Science Center, Amherst, Massachusetts 01003, USA.
authors.forename: Tanja A
authors.initials: TA
authors.lastname: Godenschwege
authors.forename: Hailan
authors.initials: H
authors.lastname: Hu
authors.forename: Xiaoliang
authors.initials: X
authors.lastname: Shan-Crofts
authors.forename: Corey S
authors.initials: CS
authors.lastname: Goodman
authors.forename: Rodney K
authors.initials: RK
authors.lastname: Murphey
mesh_terms: D000818:Animals; D030801:Animals, Genetically Modified; D002454:Cell Differentiation / Q000235:genetics*; D002490:Central Nervous System / Q000166:cytology / Q000196:embryology* / Q000378:metabolism; D004330:Drosophila / Q000166:cytology / Q000196:embryology* / Q000378:metabolism; D005260:Female; D008297:Male; D009154:Mutation / Q000235:genetics; D009421:Nervous System Malformations / Q000235:genetics / Q000378:metabolism; D010641:Phenotype; D017729:Presynaptic Terminals / Q000378:metabolism* / Q000648:ultrastructure; D017434:Protein Structure, Tertiary / Q000235:genetics; D011930:Reaction Time / Q000235:genetics; D039961:Semaphorins / Q000172:deficiency* / Q000235:genetics; D015398:Signal Transduction / Q000235:genetics*; D013570:Synaptic Membranes / Q000235:genetics / Q000378:metabolism
chemical_list: D039961:Semaphorins