Selenoprotein P/SEPP1 [B9]

Selenium is an essential trace element that is incorporated as selenocysteine into the primary structure of selenoproteins. Nutritional deficiency of selenium decreases selenoprotein concentrations and leads to pathologic conditions. Selenoprotein P (SEPP1) is a major selenoprotein that is not a member of those families. It is an extracellular glycoprotein that is present in several isoforms and is the only selenoprotein known to contain multiple selenocysteine residues. A growing body of evidence relates selenium to cancer prevention, immune system function, male fertility, cardiovascular disorder, control of the aging and neurodiseases process. Selenoproteins are thought to be responsible for the majority of these biomedical effects of selenium. It has been also implicated in the regulation of signaling pathways through catalysis of thiol/disulfide exchange.