Ethanolamine Phosphotransferase 1 (EPT1)

Selenoproteins, such as SELI, contain the rare twenty-first amino acid, selenocysteine (sec). These proteins lack common amino acid sequence motifs, but the 3-prime untranslated regions of selenoprotein genes have a common stem-loop structure, the sec insertion sequence (SECIS), that is necessary for the recognition of UGA as a sec codon rather than as a stop signal.

By searching databases using a SECIS-based method to identify putative selenoproteins, Kryukov et al. (2003) identified SELI. The deduced 397-amino acid protein contains a sec at position 387, near the C terminus. SELI mRNA was detected in a variety of tissues and cell types.