International Mammalian Genome Society

17th International Mouse Genome Conference

9-12 November 2003, Braunschweig, Germany

Plenary Presentations * Oral Presentations *
Poster Presentations: Behavioural Genetics and Genomics * Development and Stem Cells * Functional Genome Analysis * Mouse Models of Human Disease * Mouse System Biology Bioinformatics * Multigenic and Multifactorial Trait Analysis * Nutrition and Metabolic Disease * Phenotyping Methods Imaging * The Genetics and Genomics of Infectious Disease *
Verne Chapman Memorial Lecture * Table of Contents * Sponsor/Exhibitor List * Awards * Photographs

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POSTER 16 - DELTA/NOTCH SIGNALLING IS REQUIRED FOR PROPER NODE FORMATION

Przemeck GKH
GSF – Institute of Experimental Genetics

Co-Authors: 1) Vogel C, 2) Heinzmann U, 1) Beckers J, Hrabe de Angelis M
Institutions: 1) GSF – Institute of Experimental Genetics, 2) GSF – Institute of Pathology

Abstract Left-right (L/R) axis formation in vertebrates is a fundamental and evolutionary conserved process of early embryonic development and is crucial also for the proper morphogenesis of internal organs. Several genes required for the establishment and/or maintenance of L/R asymmetry include genes also expressed before node and midline development. Recently, we reported that Delta/Notch signalling is required for normal L/R determination in mice and that the loss-of-function of the Delta1 (Dll1) gene results in randomization of the direction of heart looping and embryonic turning. Along with altered expression patterns of the TGF-beta family genes Nodal, Leftb and Ebaf and the Notch-pathway genes Notch1, Notch2 and Lfng, Delta1 mutant embryos display alterations in the morphology and fine structure of the node. To investigate the latter defects in more detail we analyzed expression of several genes associated with node formation at Theiler stages (TS) 9 and 10. These expression data suggest that Delta/Notch signalling is required for proper node formation as shown, for example, by the reduced expression of Foxa2 in the primitive streak.