Molecular cloning of a novel Xenopus spalt gene (Xsal-3)

The sal (spalt) gene family is characterized by unique double zinc finger motifs and is conserved among various species from Drosophila to humans. Here we report a new Xenopus member of this family, Xsal-3. It is 38% homologous at the amino acid level to the previously reported Xenopus homologue of the spalt gene, Xsal-1. Alternatively spliced Xsal-3 transcripts give rise to RNAs coding either two or three double zinc fingers, and the longer form is expressed maternally. Xsal-3 is expressed in the neural tube, the mandibular, hyoid, and branchial arch, and the pronephric duct, which is different from the expression pattern of Xsal-1. These findings suggest that Xsal-3 may have distinct roles in early Xenopus development.