Cloning, sequencing and functional expression of a novel human thioredoxinreductase

The DNA sequence encoding a novel human thioredoxin reductase has been dete rmined, The protein is predicted to have 524 amino acids including a conser ved -Cys-Val-Asn-Val-Gly-Cys catalytic site and a selenocysteine containing C-terminal -Gly-Cys-SeCys-Gly. The predicted molecular mass is 56.5. The n ewly identified TR sequence exhibits 54% identity to a previously reported human thioredoxin reductase and 37% identity to human glutathione reductase , Transient transfection of human embryonal kidney cells results in a 5-fol d increase in thioredoxin reductase activity but no increase in glutathione reductase activity. (C) 1999 Federation of European Biochemical Societies.