A Novel TGF-β-like Gene,fugacin,Specifically Expressed in the Spemann Organizer ofXenopus

Using a differential screening strategy, we have cloned a novelXenopusgene,fugacin,related to the transforming growth factor β superfamily. Transcripts were detected primarily in the dorsal marginal zone of late blastula. Thereafter, they became highly localized to the blastopore lip of early gastrula and were not observed at later stages. This gene, which is most homologous to the mouse genenodal,displays a new pattern of cysteine residues. These findings highlight the potential role of these growth factors during early vertebrate development.