Estudi de les selenoproteïnes de

Miniopterus natalensis



Selenoproteins are a type of protein which contain selenocysteines (Sec) in their sequences. Selenocystein, the 21st aminoacid, has a selenium which is covalently bonded. Its structure is nearly identical with that of cysteine, except with selenium in place of sulfur[1]. The first time that a Sec was reported in a protein was in 1978, and GPX was the first where it was found[2]. Sec are really interesting proteins as the codon for Sec is TGA, a codon which normally acts as a stop codon in nonselenoprotein genes. It is also known that selenoproteins contains a Sec insertion sequence (SECIS) element in the 3′-UTR (untranslated region)[3]. This SECIS element is required in every eukaryotic selenoproteins in order to recode UGA to the Sec codon[4]. The objective of our project is to identify selenoproteins in Miniopterus natalensis genome by comparing by homology the selenoproteome of our specie with the ones of Myotis lucifugus and Mus musculus.

In order to carry out this project, some bioinformatic tools as well as Selenodb database were used. Also, a bioinformatic programme has been designed so it has been possible to automatize the process to predict the presence or not of selenoproteins in Miniopterus natalensis. Another programme which was used to predict SECIS elements was Selenoprotein prediction server, which was also used to obtain Seblastian predictions.

From the predictions obtained as a result, it has been able to predict 20 selenoproteins. It has also been characterized 9 cysteine homologous and 6 proteins which are responsible for the selenocysteines synthesis. However, it should be taken into consideration that it is only the prediction based on two other species. In order to complete the full selenoproteosome of Miniopterus natalensis more studies should be carried out.