Use of galactosyltransferase to assess the biological function of O-linked N-acetyl-d-glucosamine: a potential role for O-GlcNAc during cell division

Exp Cell Res. 2001 Feb 15;263(2):243-53. doi: 10.1006/excr.2000.5110.


Many cytosolic and nuclear proteins are modified by monomeric O-linked N-acetyl-d-glucosamine (O-GlcNAc). The biological functions of this form of glycosylation are unclear but evidence suggests that it heightens regulation of protein function. To assess the biological function of O-GlcNAc addition, we examined the biological effects of galactosyltransferase (GalT) microinjected into the cytoplasm of Xenopus ovarian oocytes. GalT, which catalyzes beta1-4-galactose addition to O-GlcNAc, should inhibit deglycosylation and lectin-like interactions requiring unmodified O-GlcNAc residues. Although GalT injection into diplotene-arrested oocytes has no detectable effects on cell viability, it is toxic to oocytes entering meiosis. Cell-cycle-specific toxicity is recapitulated in vitro as GalT inhibits formation of nuclei and microtubule asters from cell-free extracts of ovulated frog eggs. These observations suggest that regulation of O-GlcNAc is important for cell cycle progression and may be important in diseases in which O-GlcNAc metabolism is abnormal. The methods described here outline a viable experimental scheme for ascribing a biological function to this form of glycosylation.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Acetylglucosamine / metabolism*
  • Animals
  • Cell Cycle* / drug effects
  • Cell Cycle* / physiology
  • Cell Survival / drug effects
  • Cell-Free System
  • Galactosyltransferases / metabolism
  • Galactosyltransferases / pharmacology*
  • Microinjections
  • Microscopy, Fluorescence
  • Nuclear Envelope / metabolism
  • Oocytes / drug effects
  • Oocytes / physiology
  • Progesterone / pharmacology
  • Spindle Apparatus / drug effects
  • Spindle Apparatus / metabolism
  • Xenopus laevis


  • Progesterone
  • Galactosyltransferases
  • Acetylglucosamine