Notch synergizes with axin to regulate the activity of armadillo in Drosophila

Dev Dyn. 2006 Oct;235(10):2656-66. doi: 10.1002/dvdy.20902.

Abstract

Cell fate decisions require the integration of various signalling inputs at the level of transcription and signal transduction. Wnt and Notch signalling are two important signalling systems that operate in concert in a variety of systems in vertebrates and invertebrates. There is evidence that the Notch receptor can modulate Wnt signalling and that its target is the activity and levels of Armadillo/beta-catenin. Here, we characterize this function of Notch in relation to Axin, a key element in the regulation of Wnt signalling that acts as a scaffold for the Shaggy/GSK3beta-dependent phosphorylation of Armadillo/beta-catenin. While Notch can regulate ectopic Wingless signalling caused by loss of function of Shaggy, it can only partially regulate the ectopic Wnt signalling induced by the loss of Axin function. The same interactions are observed in tissue culture cells where we observe a synergy in between Axin and Notch in the regulation of Armadillo/beta-catenin. Our results provide evidence for a function of Axin in the regulation of Armadillo that is different from its role as a scaffold for GSK3beta.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adaptor Proteins, Signal Transducing / genetics
  • Adaptor Proteins, Signal Transducing / metabolism*
  • Adaptor Proteins, Signal Transducing / physiology
  • Animals
  • Armadillo Domain Proteins / genetics
  • Armadillo Domain Proteins / metabolism*
  • Armadillo Domain Proteins / physiology
  • Axin Protein
  • Blotting, Western
  • Drosophila / genetics
  • Drosophila / growth & development
  • Drosophila / metabolism*
  • Drosophila Proteins / genetics
  • Drosophila Proteins / metabolism*
  • Drosophila Proteins / physiology
  • Glycogen Synthase Kinase 3 / genetics
  • Glycogen Synthase Kinase 3 / metabolism
  • Glycogen Synthase Kinase 3 / physiology
  • Immunohistochemistry
  • Phosphorylation
  • RNA Interference
  • Receptors, Notch / genetics
  • Receptors, Notch / metabolism*
  • Receptors, Notch / physiology
  • Signal Transduction / genetics
  • Signal Transduction / physiology
  • Wings, Animal / growth & development
  • Wings, Animal / metabolism
  • Wnt Proteins / genetics
  • Wnt Proteins / metabolism
  • Wnt Proteins / physiology
  • beta Catenin / genetics
  • beta Catenin / metabolism
  • beta Catenin / physiology

Substances

  • Adaptor Proteins, Signal Transducing
  • Armadillo Domain Proteins
  • Axin Protein
  • Axn protein, Drosophila
  • Drosophila Proteins
  • Receptors, Notch
  • Wnt Proteins
  • beta Catenin
  • Sgg protein, Drosophila
  • Glycogen Synthase Kinase 3