title: β-catenin is O-GlcNAc glycosylated at Serine 23: implications for β-catenin's subcellular localization and transactivator function.
abstract: BACKGROUND
  We have previously reported that β-catenin is post-translationally modified with a single O-linked attachment of β-N-acetyl-glucosamine (O-GlcNAc). We showed that O-GlcNAc regulated β-catenin's subcellular localization and transcriptional activity.
  
  
  OBJECTIVE
  The objectives of this investigation were to identify the putative O-GlcNAc sites of β-catenin and the relevance of identified sites in the regulation of β-catenin's localization and transcriptional activity.
  
  
  METHODS
  Missense mutations were introduced to potential O-GlcNAc sites of pEGFP-C2-N-Terminal- or pEGFP-C2-Wild Type-β-catenin by site-directed mutagenesis. We determined the levels of O-GlcNAc-β-catenin, subcellular localization, interaction with binding partners and transcriptional activity of the various constructs.
  
  
  RESULTS
  Serine 23 of β-catenin was determined as a site for O-GlcNAc modification which regulated its subcellular distribution, its interactions with cellular partners and consequently its transcriptional activity.
  
  
  CONCLUSIONS
  O-GlcNAcylation of Serine 23 is a novel regulatory modification for β-catenin's subcellular localization and transcriptional activity. This study is the first report to characterize site specific regulation of β-catenin by the O-GlcNAc modification.
authors.affiliation: Department of Pediatrics, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, AB, Canada T6G 2E1.
authors.forename: Jacqueline R
authors.initials: JR
authors.lastname: Ha
authors.affiliation: Department of Pediatrics, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, AB, Canada T6G 2E1.
authors.forename: Li
authors.initials: L
authors.lastname: Hao
authors.affiliation: Department of Pediatrics, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, AB, Canada T6G 2E1.
authors.forename: Geetha
authors.initials: G
authors.lastname: Venkateswaran
authors.affiliation: Department of Pediatrics, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, AB, Canada T6G 2E1.
authors.forename: Yu Hao
authors.initials: YH
authors.lastname: Huang
authors.affiliation: Department of Pediatrics, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, AB, Canada T6G 2E1.
authors.forename: Elizabeth
authors.initials: E
authors.lastname: Garcia
authors.affiliation: Department of Pediatrics, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, AB, Canada T6G 2E1. Electronic address: sujata.persad@ualberta.ca.
authors.forename: Sujata
authors.initials: S
authors.lastname: Persad
mesh_terms: D000117:Acetylglucosamine / Q000378:metabolism*; D006031:Glycosylation; D006801:Humans; D010766:Phosphorylation; D011485:Protein Binding; D011499:Protein Processing, Post-Translational; D017434:Protein Structure, Tertiary; D021381:Protein Transport; D012694:Serine / Q000378:metabolism*; D014018:Tissue Distribution; D015534:Trans-Activators / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D015533:Transcriptional Activation / Q000502:physiology; D014407:Tumor Cells, Cultured; D051176:beta Catenin / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*
chemical_list: D015534:Trans-Activators; D051176:beta Catenin; D012694:Serine; D000117:Acetylglucosamine
keywords: O-GlcNAcylation; Subcellular localization; Transcriptional function; β-Catenin