Dr. Alan Diamond
My interest in anti-oxidants dates back to graduate studies in which I characterized the very unusual tRNA that inserts selenocysteine during protein synthesis in response to specific UGA codons in the mRNAs encoding selenoproteins. At that time, I didn’t realize how many human selenoproteins there were or their importance in maintain health. I gained experience in cancer molecular genetics during my post-doctoral fellowship at Harvard Medical School with Geoffrey Cooper. My first academic position was at the University of Chicago where I initially used to the tools of molecular and cell biology to study the effects of increasing the levels of anti-oxidant proteins on radiation-induced DNA damage, but returned to working on the biosynthesis and regulation of selenoproteins. These efforts evolved to the study of selenium-containing proteins in cancer prevention, with a focus on one particular selenoprotein, the cytoplasmic glutathione peroxidase (GPx-1) that detoxifies hydrogen and lipid peroxides. The work that followed has established that this protein’s levels can be regulated by the availability of selenium, increased GPx-1 levels can protect cells from DNA damage and naturally occurring polymorphisms in GPx-1 associated with disease risk are functional and contribute to ultimately determining enzyme activity. These polymorphisms also determine the cellular distribution of GPx-1 between the cytoplasm and mitochondria, consequently impacting mitochondrial function. The work on GPx-1 has been expanded to include the study of two other selenoproteins, SELENOF (Sep15) and SELENOP (SelP), as well as the non-selenocysteine containing selenium-containing protein, Selenium Binding Protein 1 (SBP1).