... synthesized in the Spemannorganizer, namely Follistatin, Chordin and Noggin[12]. These proteins are antagonists of BMP and othermembers of the TGF-b family, binding to and inhibit-ing these ... combined together, cor-respond to that of single-copy noggin homologs in other vertebrates, and could be explained as reflecting the additional genome duplication and subfunctionali-zation of the ... protein 2 in the early devel-opment of Xenopus laevis. Mech Dev 52, 357–370.7 Fainsod A, Steinbeisser H & De Robertis EM (1994) On the function of BMP-4 in patterning the marginalzone of the...