Filamin, a synaptic organizer in Drosophila, determines glutamate receptor composition and membrane growth

  1. GaYoung Lee
  2. Thomas L Schwarz  Is a corresponding author
  1. Boston Children's Hospital, United States

Abstract

Filamin is a scaffolding protein that functions in many cells as an actin-crosslinker. FLN90, an isoform of the Drosophila ortholog Filamin/cheerio that lacks the actin-binding domain, is here shown to govern the growth of postsynaptic membrane folds and the composition of glutamate receptor clusters at the larval neuromuscular junction. Genetic and biochemical analyses revealed that FLN90 is present surrounding synaptic boutons. FLN90 is required in the muscle for localization of the kinase dPak and, downstream of dPak, for localization of the GTPase Ral and the exocyst complex to this region. Consequently, Filamin is needed for growth of the subsynaptic reticulum. In addition, in the absence of filamin, type-A glutamate receptor subunits are lacking at the postsynapse, while type-B subunits cluster correctly. Receptor composition is dependent on dPak, but independent of the Ral pathway. Thus two major aspects of synapse formation, morphological plasticity and subtype-specific receptor clustering, require postsynaptic Filamin.

Article and author information

Author details

  1. GaYoung Lee

    The F.M. Kirby Neurobiology Center, Boston Children's Hospital, Boston, United States
    Competing interests
    The authors declare that no competing interests exist.
  2. Thomas L Schwarz

    The F.M. Kirby Neurobiology Center, Boston Children's Hospital, Boston, United States
    For correspondence
    Thomas.Schwarz@childrens.harvard.edu
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-7532-0250

Funding

National Institutes of Health (R01 NS041062)

  • Thomas L Schwarz

National Institutes of Health (NIH P30 HD018655)

  • Thomas L Schwarz

The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.

Copyright

© 2016, Lee & Schwarz

This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.

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  1. GaYoung Lee
  2. Thomas L Schwarz
(2016)
Filamin, a synaptic organizer in Drosophila, determines glutamate receptor composition and membrane growth
eLife 5:e19991.
https://doi.org/10.7554/eLife.19991

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https://doi.org/10.7554/eLife.19991

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