Polarized apical distribution of glycosyl-phosphatidylinositol-anchored proteins in a renal epithelial cell line Academic Article uri icon


MeSH Major

  • Glycolipids
  • Kidney
  • Membrane Proteins
  • Phosphatidylinositols


  • Polarized epithelial cell monolayers contain two distinct plasma membrane domains as delineated by the presence of tight junctions--i.e., an apical surface that faces the external environment and a basolateral surface that functions both in cell-cell contact and cell-substrate attachment. Central to the understanding of epithelial cell polarity is the question of how such cell-surface specializations are generated. A different class of membrane glycoproteins has recently emerged that may yield new insight into the mechanism underlying the biogenesis of this polarity. Members of this class contain a large extracellular protein domain linked to the membrane via glycosyl-phosphatidylinositol. Using a polarized renal epithelial cell line (Madin-Darby canine kidney), we identified endogenous glycosyl-phosphatidylinositol-anchored proteins through release by a phosphatidylinositol-specific phospholipase C. Six glycosyl-phosphatidylinositol-anchored proteins of 110, 85, 70, 55, 38, and 35 kDa were identified and appeared to be restricted to the apical surface. Our data are consistent with the notion that the glycosyl-phosphatidylinositol membrane anchor may contain the necessary information for "targeting" to the apical surface.

publication date

  • December 1988



  • Academic Article



  • eng

PubMed Central ID

  • PMC282796

PubMed ID

  • 2974157

Additional Document Info

start page

  • 9557

end page

  • 61


  • 85


  • 24