Molecular control of cell migration during Xenopus gastrulation by different Wnt signalling pathways

在脊椎动物的原肠发育中，退化中胚层的会聚延伸(CE)对于前后体轴的形成和伸长是至关重要的。在过去的几年中，规范和非规范的Wnt信号对这些形态发生运动的调节的要求已经被证明。Qur结果表明，非典范的Wnt信号通路抑制了典范途径，但反之亦然，Xnr-3是典型的Wnt途径的关键靶基因。最近，我们已经证明了非洲爪哇在收敛伸展过程中，在中胚层中协调细胞极性的旁轴原钙粘附素。我们还发现，XPAPC除了在细胞间黏附中发挥作用外，还能够触发包括JNK激活在内的信号事件。未来的研究将继续我们关于XWnt-5A信号转导的作用和典型Wnt途径的靶点的工作，其中一个重点将是Xnr-3的功能特征。我们工作中的另一个主要主题是阐明XPAPC协调极性的分子机制。为此，我们试图确定它的相互作用伙伴，它与WNT-信号的联系，以及XPAPC信号活动的细胞内下游效应器。

In vertebrate gastrulation convergent extension (CE) of the involuting mesoderm is crucial for the formation and elongation of the anterior-posterior body axis. The requirement of canonical and non-canonical Wnt-signalling for the regulation of these morphogenetic movements has been shown during the last years. Qur results show that non-canonical Wnt-signalling inhibits the canonical pathway, but not vice versa and that Xnr-3 is the key target gene of the canonical Wnt pathway for convergent extension. Recently we have demonstrated that Xenopus paraxial protocadherin coordinates cell polarity in the mesoderm during convergent extension. We also found that apart from its function in cell-cell adhesion XPAPC is capable of triggering signalling events including JNK activation. Future reseach will continue our work on the role of XWnt-5A signalling and the targets of the canonical Wnt-pathway, one focus will be functional characterisation of Xnr-3. Another major topic in our work will be to elucidate the molecular mechanisms by which XPAPC coordinates polarity. For this purpose we sought to identify its interaction partners, its connection to Wnt-signalling, and the intracellular downstream effectors of XPAPC signalling activity.