... Follistatin, Chordin and Noggin[12]. These proteins are antagonists of BMP and othermembers of the TGF-b family, binding to and inhibit-ing these signaling molecules from binding to theirreceptors ... theirreceptors in the extracellular space, thus inhibiting ven-tralizing activities. Of these proteins, Chordin has along-range effect. In Xenopus, expression of the chordingene is localized to the dorsal ... activities, being able to antagonizeBMPs. The expressed regions combined together, cor-respond to that of single-copy noggin homologs in other vertebrates, and could be explained as reflecting the additional...