Tsukushi Modulates Xnr2, FGF and BMP Signaling: Regulation of Xenopus Germ Layer Formation
Figure 1
Signaling involved in Xenopus germ layer formation.
(A) Selected signaling pathways involved in Xenopus mesoderm and endoderm formation. Activation of pathways indicated by ‘+++’, inhibition of pathways indicated by ‘−−−‘. Ectoderm = red, mesoderm = green, endoderm = blue. FGF signal activity is required for mesoderm formation in addition to activity of activin-like signaling (represented here by Xnr2). FGF and BMP signal inhibition with Xnr2 signal activation is involved in endoderm induction mechanisms. (B) Selected signaling pathways involved in Xenopus mesoderm patterning. Active BMP signaling produces mesoderm with ventral character, whereas inhibition of BMP signaling produces mesoderm of dorsal character. Also, Xnr2 expressed in the dorsal region has activity to induce dorsal mesoderm.