A bioinformatics approach to characterize mammalian selenoprotein T

The exact function and trafficking of selenoprotein T (SelT) are still unclear. This study was focused on using bioinformatics analysis as an approach to understanding the structure-function relationship of SelT and the trafficking of SelT between cellular compartments. Blast analysis revealed that SelT is present in mammals, birds, frogs, zebra fish, and green algae. Structural analyses revealed that SelT contains a CxxU motif in a thioredoxin-like fold, suggesting a redox function of SelT. Cysteine (Cys) residues were found in the place of selenocysteine in SelT Cys homologs in insects, roundworms, and plants. The SignalP program recognized signal peptides in both SelT and SelT Cys homologs. Mammalian SelT was predicted to contain an N-terminal signal peptide of 19 amino acid residues, which may be involved in targeting SelT to the endoplasmic reticulum. Finally, SelT may be localized in the plasma membrane in addition to its presence in the Golgi apparatus and the endoplasmic reticulum.