Agradecimientos:
This work was supported by the Max Planck Society; L.B. by Human Frontier
Science Program (HFSP) and Marie Curie; A.C.O., L.G.M. and J.P. by the
European Research Council (ERC) under the European Communities 7th
Framework Programme [FP7/2007–2013]/[ERC grant 207634]; J.P. by German
Research Foundation Normalverfaren [OA 53/2-1]; S.A. by Spanish Ministry of
Economy and Competitiveness (MINECO) grant PHYSDEV [FIS2012-32349]; F.J.
by the Max Planck Society; and A.C.O. by the Wellcome Trust [WT098025MA] and
the Medical Research Council (MRC) [MC_UP_1202/3. European Community's Seventh Framework Program
How signaling gradients supply positional information in a field of moving cells is an unsolved question in patterning and morphogenesis. Here, we ask how a Wnt signaling gradient regulates the dynamics of a wavefront of cellular change in a flow of cells duriHow signaling gradients supply positional information in a field of moving cells is an unsolved question in patterning and morphogenesis. Here, we ask how a Wnt signaling gradient regulates the dynamics of a wavefront of cellular change in a flow of cells during somitogenesis. Using time-controlled perturbations of Wnt signaling in the zebrafish embryo, we changed segment length without altering the rate of somite formation or embryonic elongation. This result implies specific Wnt regulation of the wavefront velocity. The observed Wnt signaling gradient dynamics and timing of downstream events support a model for wavefront regulation in which cell flow plays a dominant role in transporting positional information.[+][-]