Figure 4.

Activation of Wnt/β-catenin pathway by Xfz4S and ECD8 is LRP dependent. (A) Xfz4S (500 pg/embryo) and Xwnt-3a (0.5 pg/embryo) when coinjected into the animal caps, expression of Xnr3 was induced. This activation of Xnr3 was blocked by coinjection of 300 pg Xdkk1 or 1 ng ΔC-LRP6 and was greatly reduced by 250 pg Xdsh-DIX. (B) Induction of Xnr3 expression by injection of ECD8 (500 pg/embryo) and Xwnt-5a (50 pg/embryo) was blocked by coinjection of 300 pg Xdkk1, 1 ng ΔC-LRP6 or by 250 pg Dsh-dd2. Coinjection of a dishevelled mutant lacking the DIX domain (Dsh-ΔDIX 250 pg/embryo) had no effect on ECD8 plus Wnt-5a induced activation of Xnr3.