| Modification Notes |
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. Most of the known selenoproteins are members of the Glutathione peroxidase or iodothyronine deiodinase families. The Selenoprotein N glycoprotein localizes to the endoplasmic reticulum (ER) and contains selenocysteine at its active site. There are two isoforms associated with Selenoprotein N: isoform 1, the full-length transcript; and isoform 2, which lacks exon 3. Seleno-protein N is primarily expressed in skeletal muscle, brain, lung and placenta, but isoform 2 can also be detected in heart and stomach tissues. Mutations in SEPN1, the gene encoding for Selenoprotein, cause multiminicore disease and rigid spine muscular dystrophy. |