The Drosophila tumor suppressor gene dlg is required for normal synaptic bouton structure

Neuron. 1994 Oct;13(4):823-35. doi: 10.1016/0896-6273(94)90249-6.


The Drosophila tumor suppressor gene lethal (1) discs large (dlg) encodes a protein necessary for normal cell growth in epithelial and brain tissue. It shares high sequence identity to the mammalian synaptic proteins PSD-95 and SAP-70, whose functions are unknown. To determine the localization and role of dlg at synapses, we investigated its distribution and the effects of dlg mutations on Drosophila neuromuscular junctions. We show that dlg immunoreactivity is expressed at one type of glutamatergic synapse and is associated with both presynaptic and postsynaptic membranes. Mutations in dlg alter the expression of dlg and cause striking changes in the structure of the subsynaptic reticulum, a postsynaptic specialization at these synapses. These results indicate that dlg is required for normal synaptic structure and offer insights regarding the role of dlg homologs at vertebrate synapses.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Animals
  • Drosophila / genetics*
  • Drosophila Proteins*
  • Female
  • Gene Expression
  • Genes, Tumor Suppressor*
  • Insect Hormones / analysis
  • Insect Hormones / genetics*
  • Insect Hormones / physiology
  • Microscopy, Electron
  • Mutation
  • Neuromuscular Junction / ultrastructure
  • Presynaptic Terminals / ultrastructure*
  • Synaptic Membranes / ultrastructure
  • Tumor Suppressor Proteins*


  • Drosophila Proteins
  • Insect Hormones
  • Tumor Suppressor Proteins
  • dlg1 protein, Drosophila