Premium
The class 2 selenophosphate synthetase gene of Drosophila contains a functional mammalian‐type SECIS
Author(s) -
HirosawaTakamori Mitsuko,
Jäckle Herbert,
Vorbrüggen Gerd
Publication year - 2000
Publication title -
embo reports
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 4.584
H-Index - 184
eISSN - 1469-3178
pISSN - 1469-221X
DOI - 10.1093/embo-reports/kvd087
Subject(s) - selenoprotein , biology , selenocysteine , stop codon , genetics , gene , open reading frame , drosophila melanogaster , drosophila (subgenus) , biochemistry , peptide sequence , enzyme , cysteine , glutathione , glutathione peroxidase
Synthesis of monoselenophosphate, the selenium donor required for the synthesis of selenocysteine (Sec) is catalyzed by the enzyme selenophosphate synthetase (SPS), first described in Escherichia coli . SPS homologs were identified in archaea, mammals and Drosophila . In the latter, however, an amino acid replacement is present within the catalytic domain and lacks selenide‐dependent SPS activity. We describe the identification of a novel Drosophila homolog, Dsps2 . The open reading frame of Dsps2 mRNA is interrupted by an UGA stop codon. The 3′UTR contains a mammalian‐like Sec insertion sequence which causes translational readthrough in both transfected Drosophila cells and transgenic embryos. Thus, like vertebrates, Drosophila contains two SPS enzymes one with and one without Sec in its catalytic domain. Our data indicate further that the selenoprotein biosynthesis machinery is conserved between mammals and fly, promoting the use of Drosophila as a genetic tool to identify components and mechanistic features of the synthesis pathway.