The Xfeb gene is directly upregulated by Zic1 during early neural development

The transcription factor Zic1 plays important roles in patterning the neural plate in early vertebrate development. However, few genes that are regulated by Zic1 are known. We have identified a new direct downstream target gene of Zic1 that we have named Xfeb. Xfeb is a member of the pathogenesis-related (PR) protein superfamily and contains five tandem SCP domains. The sequence of Xfeb suggests that it may possess serine protease activity. Xfeb is expressed in the presumptive hindbrain region during neurula stages and in somite tissues later in development. Xfeb represses the hindbrain gene hoxB1 and the anterior neural gene otx2, suggesting that Xfeb is involved in regionalizing the neural plate, possibly by ensuring a posterior expression limit for otx2.