The role of N-acetylglucosaminyltransferase III and V in the post-transcriptional modifications of E-cadherin

Hum Mol Genet. 2009 Jul 15;18(14):2599-608. doi: 10.1093/hmg/ddp194. Epub 2009 Apr 29.

Abstract

It has long been recognized that E-cadherin dysfunction is a major cause of epithelial cell invasion. However, very little is known about the post-transcriptional modifications of E-cadherin and its role in E-cadherin mediated tumor progression. N-acetylglucosaminyltransferase III (GnT-III) catalyzes the formation of a bisecting GlcNAc structure in N-glycans, and has been pointed as a metastasis suppressor. N-acetylglucosaminyltransferase V (GnT-V) catalyzes the addition of beta1,6 GlcNAc branching of N-glycans, and has been associated to increase metastasis. The regulatory mechanism between E-cadherin expression and the remodeling of its oligosaccharides structures by GnT-III and GnT-V were explored in this study. We have demonstrated that wild-type E-cadherin regulates MGAT3 gene transcription resulting in increased GnT-III expression. We also showed that GnT-III and GnT-V competitively modified E-cadherin N-glycans. The GnT-III knockdown cells revealed a membrane de-localization of E-cadherin leading to its cytoplasmic accumulation. Further, the GnT-III knockdown cells also caused modifications of E-cadherin N-glycans catalyzed by GnT-III and GnT-V. Altogether our results have clarified the existence of a bidirectional crosstalk between E-cadherin and GnT-III/GnT-V that was, for the first time, reproduced in an in vivo model. This study opens new insights into the post-transcriptional modifications of E-cadherin in its biological function, in a tumor context.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Cadherins / genetics
  • Cadherins / metabolism*
  • Carcinoma / genetics
  • Carcinoma / metabolism
  • Cell Line, Tumor
  • Gene Expression
  • Glycosylation
  • Humans
  • N-Acetylglucosaminyltransferases / genetics
  • N-Acetylglucosaminyltransferases / metabolism*
  • Protein Processing, Post-Translational*
  • Protein Transport
  • Stomach Neoplasms / genetics
  • Stomach Neoplasms / metabolism

Substances

  • Cadherins
  • N-Acetylglucosaminyltransferases
  • beta-1,4-mannosyl-glycoprotein beta-1,4-N-acetylglucosaminyltransferase
  • alpha-1,6-mannosylglycoprotein beta 1,6-N-acetylglucosaminyltransferase