Open AccessA β-catenin gradient links the clock and wavefront systems in mouse embryo segmentation
Author(s) -
Alexander Aulehla,
Winfried Wiegraebe,
Valérie Baubet,
Matthias Wahl,
ChuXia Deng,
Makoto Mark Taketo,
Mark Lewandoski,
Olivier Pourquié
Publication year - 2007
Publication title -
nature cell biology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 11.38
H-Index - 369
eISSN - 1476-4679
pISSN - 1465-7392
DOI - 10.1038/ncb1679
Subject(s) - wnt signaling pathway , biology , microbiology and biotechnology , paraxial mesoderm , embryonic stem cell , circadian clock , embryo , segmentation , mesoderm , neuroscience , signal transduction , genetics , computer science , circadian rhythm , artificial intelligence , gene
Rhythmic production of vertebral precursors, the somites, causes bilateral columns of embryonic segments to form. This process involves a molecular oscillator--the segmentation clock--whose signal is translated into a spatial, periodic pattern by a complex signalling gradient system within the presomitic mesoderm (PSM). In mouse embryos, Wnt signalling has been implicated in both the clock and gradient mechanisms, but how the Wnt pathway can perform these two functions simultaneously remains unclear. Here, we use a yellow fluorescent protein (YFP)-based, real-time imaging system in mouse embryos to demonstrate that clock oscillations are independent of beta-catenin protein levels. In contrast, we show that the Wnt-signalling gradient is established through a nuclear beta-catenin protein gradient in the posterior PSM. This gradient of nuclear beta-catenin defines the size of the oscillatory field and controls key aspects of PSM maturation and segment formation, emphasizing the central role of Wnt signalling in this process.