The aim of this project is to elucidate the selenoproteome in Periophthalmodon schlosseri. Selenoproteins are proteins that include, at least, one selenocysteine (represented with U or Sec), which is considered the 21st amino acid. The main limitation in its identification is that selenocysteine is encoded by UGA, usually known as a STOP codon. The duality of this signal explains why this kind of proteins have been dismissed or wrongly annotated for several years.

In order to detect the selenoproteins and its machinery synthesis in Periophthalmodon schlosseri, an homology-based in silico comparison between the selenoproteome of Zebrafish and Periophthalodon’s genome was performed. Zebrafish is the elected organism due to it is the closer evolutionary-related model organism that have a well-characterized selenoproteome. Different bioinformatics tools such as tBLASTn, Exonerate, T_Coffe or SECISearch were required. Additionally an automatic program was designed to facilitate the analysis. Obtained results show high homology between Zebrafish and Periophthalodon’s selenoproteome. In fact, results allowed the characterization of 28 selenoproteins, 11 cys-containing selenoprotein homologues and 9 machinery proteins.

This study contributes with the identification of selenoproteins in new-sequenciated organisms.