Evolution of SUMO Function and Chain Formation in Insects

摘要: SUMOylation, the covalent binding of Small Ubiquitin-like Modifier (SUMO) to target proteins, is a posttranslational modification that regulates critical cellular processes in eukaryotes. In insects, SUMOylation has been studied holometabolous species, particularly dipteran Drosophila melanogaster, which contains single SUMO gene (smt3). This led assumption insects contain gene. However, analysis insect genomes shows basal two genes, orthologous vertebrate SUMO1 and SUMO2/3. Our phylogenetical reveals duplicated giving rise SUMO2/3 families early Metazoan evolution, later evolution lost after Hymenoptera divergence. To explore consequences this loss, we have examined characteristics different biological functions genes (SUMO1 SUMO3) hemimetabolous cockroach Blattella germanica compared them with those Smt3. Here, show metamorphic role evolutionary conserved although there regulatory switch from SUMO3 more derived ones. We also that, unlike vertebrates, proteins cannot form polySUMO chains due loss lysine residues within N-terminal part protein. Furthermore, formation by expression ectopic human deleterious effect Drosophila. These findings contribute understanding functional genes.