Article

Besse, F. et al. The Ig cell adhesion molecule Basigin controls compartmentalization and vesicle release at Drosophila melanogaster synapses. J. Cell Biol. 177, 843-855

Developmental Biology Unit, European Molecular Biology Laboratory, D-69117 Heidelberg, Germany.
The Journal of Cell Biology (Impact Factor: 9.83). 07/2007; 177(5):843-55. DOI: 10.1083/jcb.200701111
Source: PubMed

ABSTRACT

Synapses can undergo rapid changes in size as well as in their vesicle release function during both plasticity processes and development. This fundamental property of neuronal cells requires the coordinated rearrangement of synaptic membranes and their associated cytoskeleton, yet remarkably little is known of how this coupling is achieved. In a GFP exon-trap screen, we identified Drosophila melanogaster Basigin (Bsg) as an immunoglobulin domain-containing transmembrane protein accumulating at periactive zones of neuromuscular junctions. Bsg is required pre- and postsynaptically to restrict synaptic bouton size, its juxtamembrane cytoplasmic residues being important for that function. Bsg controls different aspects of synaptic structure, including distribution of synaptic vesicles and organization of the presynaptic cortical actin cytoskeleton. Strikingly, bsg function is also required specifically within the presynaptic terminal to inhibit nonsynchronized evoked vesicle release. We thus propose that Bsg is part of a transsynaptic complex regulating synaptic compartmentalization and strength, and coordinating plasma membrane and cortical organization.

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    • "In Drosophila, depletion of CD147 causes lethality and specific knockdown in the eye leads to misplaced subcellular organelles in photoreceptor cells [76]. Furthermore, CD147-depleted flies have misplaced glial cellphotoreceptor interactions and altered synaptic vesicle release [77]; these phenotypes may be secondary to a conserved YEKRRK sequence in the cytoplasmic tail [78]. Thus, data from the knockout models suggests CD147 has a multitude of functions including regulation of cytoskeletal remodeling, assembly of cell-cell interaction modules and subcellular vesicle distribution that span an array of biologic functions. "
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