Egfr signaling regulates ommatidial rotation and cell motility in the Drosophila eye via MAPK/Pnt signaling and the Ras effector Canoe/AF6

Development. 2003 Nov;130(22):5413-23. doi: 10.1242/dev.00759. Epub 2003 Sep 24.

Abstract

Epidermal Growth Factor-receptor (Egfr) signaling is evolutionarily conserved and controls a variety of different cellular processes. In Drosophila these include proliferation, patterning, cell-fate determination, migration and survival. Here we provide evidence for a new role of Egfr signaling in controlling ommatidial rotation during planar cell polarity (PCP) establishment in the Drosophila eye. Although the signaling pathways involved in PCP establishment and photoreceptor cell-type specification are beginning to be unraveled, very little is known about the associated 90 degrees rotation process. One of the few rotation-specific mutations known is roulette (rlt) in which ommatidia rotate to a random degree, often more than 90 degrees. Here we show that rlt is a rotation-specific allele of the inhibitory Egfr ligand Argos and that modulation of Egfr activity shows defects in ommatidial rotation. Our data indicate that, beside the Raf/MAPK cascade, the Ras effector Canoe/AF6 acts downstream of Egfr/Ras and provides a link from Egfr to cytoskeletal elements in this developmentally regulated cell motility process. We provide further evidence for an involvement of cadherins and non-muscle myosin II as downstream components controlling rotation. In particular, the involvement of the cadherin Flamingo, a PCP gene, downstream of Egfr signaling provides the first link between PCP establishment and the Egfr pathway.

Publication types

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

MeSH terms

  • Animals
  • DNA-Binding Proteins
  • Drosophila / embryology*
  • Drosophila / genetics
  • Drosophila Proteins / metabolism
  • ErbB Receptors / metabolism*
  • Eye / embryology*
  • Eye Proteins / genetics
  • Eye Proteins / metabolism
  • Kinesins / metabolism
  • Ligands
  • Mitogen-Activated Protein Kinases / physiology
  • Myosins / metabolism
  • Nerve Tissue Proteins / genetics
  • Nerve Tissue Proteins / metabolism
  • Proto-Oncogene Proteins / physiology
  • Signal Transduction / genetics
  • Signal Transduction / physiology*
  • Transcription Factors
  • ras Proteins / metabolism

Substances

  • DNA-Binding Proteins
  • Drosophila Proteins
  • Eye Proteins
  • Ligands
  • Nerve Tissue Proteins
  • Proto-Oncogene Proteins
  • Transcription Factors
  • cno protein, Drosophila
  • pnt protein, Drosophila
  • aos protein, Drosophila
  • ErbB Receptors
  • Mitogen-Activated Protein Kinases
  • Myosins
  • Kinesins
  • ras Proteins