Fiche publication
Date publication
juin 2010
Auteurs
Membres identifiés du Cancéropôle Est :
Dr FREUND Jean-Noël
Tous les auteurs :
Coant N, Ben Mkaddem S, Pedruzzi E, Guichard C, Treton X, Ducroc R, Freund JN, Cazals-Hatem D, Bouhnik Y, Woerther PL, Skurnik D, Grodet A, Fay M, Biard D, Lesuffleur T, Deffert C, Moreau R, Groyer A, Krause KH, Daniel F, Ogier-Denis E
Lien Pubmed
Résumé
The homeostatic self-renewal of the colonic epithelium requires coordinated regulation of the canonical Wnt/beta-catenin and Notch signaling pathways to control proliferation and lineage commitment of multipotent stem cells. However, the molecular mechanisms by which the Wnt/beta-catenin and Notch1 pathways interplay in controlling cell proliferation and fate in the colon are poorly understood. Here we show that NADPH oxidase 1 (NOX1), a reactive oxygen species (ROS)-producing oxidase that is highly expressed in colonic epithelial cells, is a pivotal determinant of cell proliferation and fate that integrates Wnt/beta-catenin and Notch1 signals. NOX1-deficient mice reveal a massive conversion of progenitor cells into postmitotic goblet cells at the cost of colonocytes due to the concerted repression of phosphatidylinositol 3-kinase (PI3K)/AKT/Wnt/beta-catenin and Notch1 signaling. This conversion correlates with the following: (i) the redox-dependent activation of the dual phosphatase PTEN, causing the inactivation of the Wnt pathway effector beta-catenin, and (ii) the downregulation of Notch1 signaling that provokes derepression of mouse atonal homolog 1 (Math1) expression. We conclude that NOX1 controls the balance between goblet and absorptive cell types in the colon by coordinately modulating PI3K/AKT/Wnt/beta-catenin and Notch1 signaling. This finding provides the molecular basis for the role of NOX1 in cell proliferation and postmitotic differentiation.
Référence
Mol Cell Biol. 2010 Jun;30(11):2636-50
