The Drosophila Larval Neuromuscular Junction as a Model for Scaffold Complexes at Glutamatergic Synapses: Benefits and Limitations

Abstract

Based on unbeatable genetic accessibility and relative simplicity, the Drosophila larval neuromuscular junction has become a widely used model system for studying functional and structural aspects of excitatory glutamatergic synapses. Membrane-associated guanylate kinase–like proteins (MAGUKs) are first-order scaffolding molecules enriched at many cellular junctions, including synapses, where they coordinate multiple binding partners, including cell adhesion molecules and ion channels. The enrichment of the prototypic MAGUK Discs-Large at larval NMJs apparently parallels the high abundance of its homologs at excitatory synapses in the mammalian central nervous system. Here, the authors review selected aspects of the long-standing work on Dlg at fly neuromuscular junctions, thereby scrutinizing its subcellular localization, function, and regulation with regard to corresponding aspects of MAGUKs in vertebrate neurons.

Keywords::

• Dlg
• glutamate receptors
• MAGUK
• postsynaptic density
• PSD-95
• subsynaptic reticulum

Declaration of interest: Work in the authors' laboratory is supported by the Deutsche Forschungsgemeinschaft to U.T. and E.D.G. (SFB 854/TP8 and SFB 779/TPB9) and an IfN special project to U.T.