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Selenoproteins And Selenocysteine Insertion System In The Model Plant Cell System, Chlamydomonas Reinhardtii, Sergey V. Novoselov, Mahadev Rao, Natalia V. Onoshko, Huijun Zhi, Gregory V. Kryukov, Youbin Xiang, Donald P. Weeks, Dolph A. Hatfield, Vadim Gladyshev

Vadim Gladyshev Publications

Known eukaryotic selenocysteine (Sec)-containing proteins are animal proteins, whereas selenoproteins have not been found in yeast and plants. Surprisingly, we detected selenoproteins in a member of the plant kingdom, Chlumydomonas reinhardtii, and directly identified two of them as phospholipid hydroperoxide glutathione peroxidase and selenoprotein W homologs. Moreover, a selenocysteyl-tRNA was isolated that recognized specifically the Sec codon UGA. Subsequent gene cloning and bioinformatics analyses identified eight additional selenoproteins, including methionine-Ssulfoxide reductase, a selenoprotein specific to Chlumydomonas. Chlumydomonas selenoprotein genes contained selenocysteine insertion sequence (SECIS) elements that were similar, but not identical, to those of animals. These SECIS elements could direct …