O-GlcNAcylation of tubulin inhibits its polymerization

Amino Acids. 2011 Mar;40(3):809-18. doi: 10.1007/s00726-010-0698-9. Epub 2010 Jul 28.


The attachment of O-linked β-N-acetylglucosamine (O-GlcNAc) to proteins is an abundant and reversible modification that involves many cellular processes including transcription, translation, cell proliferation, apoptosis, and signal transduction. Here, we found that the O-GlcNAc modification pattern was altered during all-trans retinoic acid (tRA)-induced neurite outgrowth in the MN9D neuronal cell line. We identified several O-GlcNAcylated proteins using mass spectrometric analysis, including α- and β-tubulin. Further analysis of α- and β-tubulin revealed that O-GlcNAcylated peptides mapped between residues 173 and 185 of α-tubulin and between residues 216 and 238 of β-tubulin, respectively. We found that an increase in α-tubulin O-GlcNAcylation reduced heterodimerization and that O-GlcNAcylated tubulin did not polymerize into microtubules. Consequently, when O-GlcNAcase inhibitors were co-incubated with tRA, the extent of neurite outgrowth was decreased by 20% compared to control. Thus, our data indicate that the O-GlcNAcylation of tubulin negatively regulates microtubule formation.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Acetylglucosamine / metabolism*
  • Amino Acid Sequence
  • Cell Line
  • Down-Regulation*
  • Glycosylation
  • HEK293 Cells
  • Humans
  • Microtubules / chemistry
  • Microtubules / metabolism
  • Molecular Sequence Data
  • Neurons / cytology
  • Neurons / metabolism
  • Polymerization
  • Tubulin / chemistry
  • Tubulin / genetics
  • Tubulin / metabolism*


  • Tubulin
  • Acetylglucosamine