Cell
Volume 107, Issue 5, 30 November 2001, Pages 591-603
Journal home page for Cell

Article
Drosophila Fragile X-Related Gene Regulates the MAP1B Homolog Futsch to Control Synaptic Structure and Function

https://doi.org/10.1016/S0092-8674(01)00589-XGet rights and content
Under an Elsevier user license
open archive

Abstract

Fragile X mental retardation gene (FMR1) encodes an RNA binding protein that acts as a negative translational regulator. We have developed a Drosophila fragile X syndrome model using loss-of-function mutants and overexpression of the FMR1 homolog (dfxr). dfxr nulls display enlarged synaptic terminals, whereas neuronal overexpression results in fewer and larger synaptic boutons. Synaptic structural defects are accompanied by altered neurotransmission, with synapse type-specific regulation in central and peripheral synapses. These phenotypes mimic those observed in mutants of microtubule-associated Futsch. Immunoprecipitation of dFXR shows association with futsch mRNA, and Western analyses demonstrate that dFXR inversely regulates Futsch expression. dfxr futsch double mutants restore normal synaptic structure and function. We propose that dFXR acts as a translational repressor of Futsch to regulate microtubule-dependent synaptic growth and function.

Cited by (0)

4

These authors contributed equally to this work.