XB-ART-6796Semin Cell Dev Biol June 1, 2002; 13 (3): 243-9.
Non-canonical Wnt signaling in Xenopus: regulation of axis formation and gastrulation.
Wnt proteins form a family of secreted glycoproteins that are involved in different developmental processes such as differentiation, proliferation, cell migration and cell polarity. To exert its function, Wnt proteins activate different intracellular signaling cascades. Whereas the canonical, Wnt/beta-catenin pathway is well characterized, less is known about the function of non-canonical Wnt pathways in vertebrates. I here summarize recent findings implicating important roles for Wnt/Ca(2+) and Wnt/JNK signaling during different aspects of early Xenopus laevis development, namely axis formation and gastrulation movements.
PubMed ID: 12137733
Article link: Semin Cell Dev Biol
Species referenced: Xenopus
Genes referenced: camk2g ctnnb1 dvl2 mapk8
Article Images: [+] show captions
|Figure 1. Wnt signaling pathways in early Xenopus embryos. Only major components of the pathways are shown and discussed in the text. For detailed description of Wnt pathways see References 1–4. Components that interact with dishevelled and which might route incoming Wnt signals into specific directions are given in italic.|
|Figure 2. Establishing the dorso–ventral axis in Xenopus embryos. During cortex rotation, dishevelled (dsh) and β-catenin accumulate on the dorsal side of the embryo and activate dorsal marker genes as discussed in the text. Before the onset of zygotic transcription at midblastula transition, a higher CamKII activity can be measured on the ventral side. CamKII is involved in activating ventral marker genes.|
|Figure 3. CamKII can phenocopy the effect of Wnt-5A. CamKII blocks axis duplication elicited by injection of Xwnt-8 and thus can phenocopy the effect of Wnt-5A class members. However, CamKII does not revert axis duplication triggered by injections of a dominant-negative BMP receptor (tBR).|