Mannosamine, a novel inhibitor of glycosylphosphatidylinositol incorporation into proteins Academic Article uri icon


MeSH Major

  • Glycolipids
  • Hexosamines
  • Phosphatidylinositols
  • Protozoan Proteins


  • Mannosamine (2-amino-2-deoxy D-mannose) is shown here to block the incorporation of glycosylphosphatidylinositol (GPI) into GPI-anchored proteins. The amino sugar drastically reduced the surface expression of a recombinant GPI-anchored protein in polarized MDCK cells, converted this apical membrane-bound protein to an unpolarized secretory product and blocked the expression of endogenous GPI-anchored proteins. Furthermore, it specifically inhibited the incorporation of [3H]ethanolamine (a GPI component) into mammalian and trypanosomal GPI-anchored proteins and into a well characterized GPI-lipid of Trypanosoma brucei. These results suggest that mannosamine converted an apical GPI-anchored protein to a non-polarized secretory product by depleting transfer competent GPI-precursor lipids. Our inhibitor studies provide new independent evidence for the apical targeting role of GPI in polarized epithelia and open the way towards a greater understanding of the functional role of GPI in membrane trafficking and cell regulation.

publication date

  • December 1991



  • Academic Article



  • eng

PubMed Central ID

  • PMC452876

PubMed ID

  • 1829673

Additional Document Info

start page

  • 1969

end page

  • 77


  • 10


  • 8