The Early Metazoan Trichoplax adhaerens Possesses a Functional O-GlcNAc System *

摘要

Background: Protein O -GlcNAcylation and orthologues of O -GlcNAc transferase (OGT) and O -GlcNAcase (OGA) occur separately or together in all kingdoms of life. Results: The basal metazoan Trichoplax adhaerens is the simplest organism to possess functional OGT, OGA, and protein O -GlcNAcylation together. Conclusion: Reversible protein O -GlcNAcylation is conserved throughout the metazoan lineage. Significance: T. adhaerens can be used as a reductionist model to identify evolutionarily conserved O -GlcNAc targets. Protein O -GlcNAcylation is a reversible post-translational signaling modification of nucleocytoplasmic proteins that is essential for embryonic development in bilateria. In a search for a reductionist model to study O -GlcNAc signaling, we discovered the presence of functional O -GlcNAc transferase (OGT), O -GlcNAcase (OGA), and nucleocytoplasmic protein O -GlcNAcylation in the most basal extant animal, the placozoan Trichoplax adhaerens . We show via enzymatic characterization of Trichoplax OGT/OGA and genetic rescue experiments in Drosophila melanogaster that these proteins possess activities/functions similar to their bilaterian counterparts. The acquisition of O -GlcNAc signaling by metazoa may have facilitated the rapid and complex signaling mechanisms required for the evolution of multicellular organisms.