title: Dual functionality of O-GlcNAc transferase is required for Drosophila development.
abstract: Post-translational modification of intracellular proteins with O-linked N-acetylglucosamine (O-GlcNAc) catalysed by O-GlcNAc transferase (OGT) has been linked to regulation of diverse cellular functions. OGT possesses a C-terminal glycosyltransferase catalytic domain and N-terminal tetratricopeptide repeats that are implicated in protein-protein interactions. Drosophila OGT (DmOGT) is encoded by super sex combs (sxc), mutants of which are pupal lethal. However, it is not clear if this phenotype is caused by reduction of O-GlcNAcylation. Here we use a genetic approach to demonstrate that post-pupal Drosophila development can proceed with negligible OGT catalysis, while early embryonic development is OGT activity-dependent. Structural and enzymatic comparison between human OGT (hOGT) and DmOGT informed the rational design of DmOGT point mutants with a range of reduced catalytic activities. Strikingly, a severely hypomorphic OGT mutant complements sxc pupal lethality. However, the hypomorphic OGT mutant-rescued progeny do not produce F2 adults, because a set of Hox genes is de-repressed in F2 embryos, resulting in homeotic phenotypes. Thus, OGT catalytic activity is required up to late pupal stages, while further development proceeds with severely reduced OGT activity.
authors.affiliation: MRC Protein Phosphorylation and Ubiquitylation Unit, University of Dundee, Dundee, UK.
authors.forename: Daniel
authors.initials: D
authors.lastname: Mariappa
authors.affiliation: MRC Protein Phosphorylation and Ubiquitylation Unit, University of Dundee, Dundee, UK.
authors.forename: Xiaowei
authors.initials: X
authors.lastname: Zheng
authors.affiliation: MRC Protein Phosphorylation and Ubiquitylation Unit, University of Dundee, Dundee, UK.
authors.forename: Marianne
authors.initials: M
authors.lastname: Schimpl
authors.affiliation: Division of Molecular Microbiology, University of Dundee, Dundee, UK.
authors.forename: Olawale
authors.initials: O
authors.lastname: Raimi
authors.affiliation: MRC Protein Phosphorylation and Ubiquitylation Unit, University of Dundee, Dundee, UK.
authors.forename: Andrew T
authors.initials: AT
authors.lastname: Ferenbach
authors.affiliation: Division of Cell and Developmental Biology, College of Life Sciences, University of Dundee, Dundee, UK.
authors.forename: H-Arno J
authors.initials: HA
authors.lastname: Müller
authors.affiliation: MRC Protein Phosphorylation and Ubiquitylation Unit, University of Dundee, Dundee, UK Division of Molecular Microbiology, University of Dundee, Dundee, UK dmfvanaalten@dundee.ac.uk.
authors.forename: Daan M F
authors.initials: DM
authors.lastname: van Aalten
mesh_terms: D000818:Animals; D004330:Drosophila / Q000201:enzymology* / Q000254:growth & development; D029721:Drosophila Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D006801:Humans; D017351:N-Acetylglucosaminyltransferases / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D011487:Protein Conformation; D013379:Substrate Specificity
chemical_list: D029721:Drosophila Proteins; D017351:N-Acetylglucosaminyltransferases; C449880:O-GlcNAc transferase
keywords: Drosophila development; Hox; O-GlcNAc; O-GlcNAc transferase