Fig. 1. Primary structure of the urea transporter (UT) isolated from the kidney of Triakis scyllia. The deduced amino acid sequence is aligned with those of the Squalus acanthias UT (accession number AF257331), rat UT-A2 (U09957) and rat UT-B2 (U81518) using the Clustal algorithm. Amino acid residues identical to the Triakis UT are indicated in black. A putative N-glycosylation site and polypeptides used as antigens to generate antibodies are indicated with horizontal bars.