The protocadherin Flamingo is required for axon target selection in the Drosophila visual system

Nat Neurosci. 2003 Jun;6(6):557-63. doi: 10.1038/nn1063.

Abstract

Photoreceptor neurons (R cells) in the Drosophila visual system elaborate a precise map of visual space in the brain. The eye contains some 750 identical modules called ommatidia, each containing eight photoreceptor cells (R1-R8). Cells R1-R6 synapse in the lamina; R7 and R8 extend through the lamina and terminate in the underlying medulla. In a screen for visual behavior mutants, we identified alleles of flamingo (fmi) that disrupt the precise maps elaborated by these neurons. These mutant R1-R6 neurons select spatially inappropriate targets in the lamina. During target selection, Flamingo protein is dynamically expressed in R1-R6 growth cones. Loss of fmi function in R cells also disrupts the local pattern of synaptic terminals in the medulla, and Flamingo is transiently expressed in R8 axons as they enter the target region. We propose that Flamingo-mediated interactions between R-cell growth cones within the target field regulate target selection.

Publication types

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

MeSH terms

  • Alleles
  • Animals
  • Body Patterning / genetics
  • Brain / growth & development*
  • Brain / metabolism
  • Brain / ultrastructure
  • Brain Mapping
  • Cadherins / genetics
  • Cadherins / metabolism*
  • Cell Adhesion / genetics
  • Cell Communication / genetics
  • Cell Differentiation / genetics*
  • Drosophila Proteins
  • Drosophila melanogaster / growth & development*
  • Drosophila melanogaster / metabolism
  • Drosophila melanogaster / ultrastructure
  • Gene Expression Regulation, Developmental / genetics
  • Growth Cones / metabolism*
  • Growth Cones / ultrastructure
  • Microscopy, Electron
  • Mosaicism / genetics
  • Mutation / genetics
  • Photoreceptor Cells, Invertebrate / growth & development*
  • Photoreceptor Cells, Invertebrate / metabolism
  • Photoreceptor Cells, Invertebrate / ultrastructure
  • Synapses / metabolism
  • Synapses / ultrastructure
  • Visual Pathways / growth & development*
  • Visual Pathways / metabolism
  • Visual Pathways / ultrastructure

Substances

  • Cadherins
  • Drosophila Proteins
  • stan protein, Drosophila