Modulation of the ligand-independent traffic of Notch by Axin and Apc contributes to the activation of Armadillo in Drosophila

Silvia Muñoz-Descalzo, Katarzyna Tkocz, Tina Balayo, Alfonso Martinez-Arias

Research output: Contribution to journalArticle

21 Citations (Scopus)

Abstract

There is increasing evidence for close functional interactions between Wnt and Notch signalling. In many instances, these are mediated by convergence of the signalling events on common transcriptional targets, but there are other instances that cannot be accounted for in this manner. Studies in Drosophila have revealed that an activated form of Armadillo, the effector of Wnt signalling, interacts with, and is modulated by, the Notch receptor. Specifically, the ligand-independent traffic of Notch serves to set up a threshold for the amount of this form of Armadillo and therefore for Wnt signalling. In the current model of Wnt signalling, a complex assembled around Axin and Apc allows GSK3 (Shaggy) to phosphorylate Armadillo and target it for degradation. However, genetic experiments suggest that the loss of function of any of these three elements does not have the same effect as elevating the activity of β-catenin. Here, we show that Axin and Apc, but not GSK3, modulate the ligandindependent traffic of Notch. This finding helps to explain unexpected differences in the phenotypes obtained by different ways of activating Armadillo function and provides further support for the notion that Wnt and Notch signalling form a single functional module.
Original languageEnglish
Pages (from-to)1501-1506
Number of pages6
JournalDevelopment
Volume138
Issue number8
Early online date9 Mar 2011
DOIs
Publication statusPublished - 15 Apr 2011

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Armadillos
Drosophila
Ligands
Notch Receptors
beta Catenin
Phenotype

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Modulation of the ligand-independent traffic of Notch by Axin and Apc contributes to the activation of Armadillo in Drosophila. / Muñoz-Descalzo, Silvia; Tkocz, Katarzyna; Balayo, Tina; Martinez-Arias, Alfonso.

In: Development, Vol. 138, No. 8, 15.04.2011, p. 1501-1506.

Research output: Contribution to journalArticle

Muñoz-Descalzo, Silvia ; Tkocz, Katarzyna ; Balayo, Tina ; Martinez-Arias, Alfonso. / Modulation of the ligand-independent traffic of Notch by Axin and Apc contributes to the activation of Armadillo in Drosophila. In: Development. 2011 ; Vol. 138, No. 8. pp. 1501-1506.
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