Abstract
In vertebrates, the patterning of anterior-posterior (AP) axis is a fundamental process during embryogenesis. Wnt and FGF signalling pathways play important roles in regulating the patterning of embryo AP axis. Mouse Tbx6 encodes a transcription factor that has been demonstrated to be involved in the specification of the posterior tissue in mouse embryonic body. Here, we prove that morpholino-induced knockdown of XTbx6 impairs posterior development, indicating the requirement of XTbx6 in this process. Meanwhile, gain of XTbx6 function is sufficient to induce ectopic posterior structures in Xenopus embryos. Furthermore, XTbx6 activates the expression of Xwnt8 and FGF8, which are two mediators of posterior development, suggesting a mechanism by which XTbx6 modulates posterior patterning via Wnt and FGF signalling pathway activation.
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Acknowledgements
We thank Dr Peter S Klein (Department of Medicine and Cell and Developmental Biology, University of Pennsylvania), Dr Christof Niehrs (Division of Molecular Embryology German Cancer Research Center) for constructs, and Dr Schneider (Max-Planck-Institut fur Entwicklungsbiologie) for b-catenin antibody. We also thank Dr Jinhu Wang and Dr Zhao He for discussion of the project and critical reading of the manuscript. This work was supported by the National Natural Science Foundation of China (90408005, 30270650) and the National Key Project for Basic Science Research of China (2001CB509901).
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Lou, X., Fang, P., Li, S. et al. Xenopus Tbx6 mediates posterior patterning via activation of Wnt and FGF signalling. Cell Res 16, 771–779 (2006). https://doi.org/10.1038/sj.cr.7310093
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DOI: https://doi.org/10.1038/sj.cr.7310093
