N-glycosylation gene DPAGT1 is a target of the Wnt/beta-catenin signaling pathway

J Biol Chem. 2010 Oct 8;285(41):31164-73. doi: 10.1074/jbc.M110.149195. Epub 2010 Aug 6.

Abstract

Protein N-glycosylation and the Wnt/β-catenin signaling pathways play critical roles in development and cancer. Although N-glycosylation has been shown to influence Wnt signaling through its effects on Wnt ligands, it is unclear whether the Wnt/β-catenin pathway impacts protein N-glycosylation. In this study, we show that promoters of the first N-glycosylation gene, DPAGT1, from Chinese hamster ovary (CHO), Madin-Darby canine kidney (MDCK), and human epidermoid carcinoma (A253) cells contain the T-cell factor/lymphoid enhancer-binding factor (TCF/LEF) consensus sequence. Treatment of cells with a Wnt activator, lithium chloride, up-regulated DPAGT1 transcript levels that correlated with an increase in the β-catenin abundance. Furthermore, exposure of cells to a Wnt receptor ligand, Wnt3a, resulted in an increase in the DPAGT1 transcript levels that was abrogated by the Wnt inhibitor, Dickkopf-1. DNA mobility shift assays revealed specific protein complexes at the DPAGT1 TCF/LEF binding region that were competed off with antibodies to either Tcf3/4 or β-catenin. Chromatin immunoprecipitation analysis confirmed the presence of β-catenin at the DPAGT1 promoter in vivo. In addition, the DPAGT1 TCF/LEF sequence drove the expression of the luciferase reporter gene. Furthermore, up-regulation of DPAGT1 transcripts by Wnt3a led to altered N-glycosylation of E-cadherin. Interestingly, the DPAGT1 TCF/LEF sequence also interacted with γ-catenin, a close homologue of β-catenin, although not in a lithium chloride-dependent manner. Our results provide the first evidence that the Wnt/β-catenin signaling pathway regulates the metabolic pathway of protein N-glycosylation by targeting DPAGT1 expression. Moreover, they suggest the existence of another regulatory mechanism involving the interaction of Tcf with γ-catenin at the DPAGT1 promoter.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Adjuvants, Immunologic / pharmacology
  • Amino Acid Motifs
  • Animals
  • Basic Helix-Loop-Helix Leucine Zipper Transcription Factors / genetics
  • Basic Helix-Loop-Helix Leucine Zipper Transcription Factors / metabolism
  • Basic Helix-Loop-Helix Transcription Factors / genetics
  • Basic Helix-Loop-Helix Transcription Factors / metabolism
  • CHO Cells
  • Cadherins / genetics
  • Cadherins / metabolism
  • Cricetinae
  • Cricetulus
  • Desmoplakins / genetics
  • Desmoplakins / metabolism
  • Dogs
  • Gene Expression Regulation, Enzymologic / drug effects
  • Gene Expression Regulation, Enzymologic / physiology*
  • Glycosylation / drug effects
  • Humans
  • Intercellular Signaling Peptides and Proteins / genetics
  • Intercellular Signaling Peptides and Proteins / metabolism
  • Lithium Chloride / pharmacology
  • N-Acetylglucosaminyltransferases / biosynthesis*
  • N-Acetylglucosaminyltransferases / genetics
  • Promoter Regions, Genetic / physiology
  • Signal Transduction / drug effects
  • Signal Transduction / physiology*
  • Transcription Factor 4
  • Transcription Factors / genetics
  • Transcription Factors / metabolism
  • Wnt Proteins / genetics
  • Wnt Proteins / metabolism*
  • Wnt3 Protein
  • Wnt3A Protein
  • beta Catenin / genetics
  • beta Catenin / metabolism*
  • gamma Catenin

Substances

  • Adjuvants, Immunologic
  • Basic Helix-Loop-Helix Leucine Zipper Transcription Factors
  • Basic Helix-Loop-Helix Transcription Factors
  • Cadherins
  • DKK1 protein, human
  • Desmoplakins
  • Intercellular Signaling Peptides and Proteins
  • JUP protein, human
  • TCF3 protein, human
  • TCF4 protein, human
  • Transcription Factor 4
  • Transcription Factors
  • WNT3A protein, human
  • Wnt Proteins
  • Wnt3 Protein
  • Wnt3A Protein
  • beta Catenin
  • gamma Catenin
  • N-Acetylglucosaminyltransferases
  • dolichyl-phosphate alpha-N-acetylglucosaminyltransferase
  • Lithium Chloride