Selective Transport of Glycolipid Molecules Containing N-acetylgalactosamine to the Basolateral Domain of Mouse Hepatocyte Plasma Membrane

To determine whether N-acetylgalactosamine (GaINAc)-or galactose (Gal)-containing components are present on the plasma membrane of hepatocytes, and, if so, to examine the distribution of the components on the plasma membrane, the binding of Dorichos biflorus agglutinin or soybean agglutinin to the plasma membrane of mouse hepatocytes was demonstrated histochemically. In addition, to determine the nature of the components containing GaINAc or Gal, the lectin binding sites were extracted from the plasma membrane and subjected to electrophoresis followed by lectin binding assay. Plasma membrane fractions from mouse hepatocytes included GaINAc-or Gal-containing components, and the components were glycolipid. The terminal sugar in the sugar chain of the glycolipid molecules was GaINAc. The glycolipid molecules containing GaINAc were predominantly localized along the basolateral (sinusoidal plus lateral) domain of the plasma membrane. Colchicine inhibited the transport of the glycolipid molecules to the plasma membrane. Therefore, glycolipid molecules containing GaINAc are selectively transported to the basolateral domain of the plasma membrane of mouse hepatocytes via vesicular transport.