Cloning and sequencing of a COUP transcription factor gene expressed in Xenopus embryos

A cDNA clone encoding COUP transcription factor, a member of the steroid/thyroid receptor superfamily, has been isolated from a Xenopus neurula (stage 17 embryo) library. Sequencing of this clone reveals an open reading frame encoding a 397 amino acid protein. The amino acid sequence of Xenopus COUP has been compared with its human and Drosophila homologues showing that there are few similarities within the amino-terminal region, whereas the remainder of the protein, including the putative DNA and ligand binding domains, is very well conserved.