Incorporation of the hexose analogue 2-deoxy-D-galactose into membrane glycoproteins in HepG2 cells.
The incorporation of 2-deoxy-D-galactose into the oligosaccharide moieties of glycoproteins and the consequences of 2-deoxy-D-galactose treatment on the fucosylation of glycoproteins were investigated in the human hepatoma cell line HepG2. Using different methods, it was shown that treatment of HepG2 cells with 2-deoxy-D-galactose leads to an incorporation of 2-deoxy-D-galactose and a decrease of L-fucose incorporation into the oligosaccharides of glycoproteins. The extent of labeling by L-[3H]fucose was determined by removing L-[3H]fucose from labeled cells with the aid of a purified alpha 1,2-fucosidase from Aspergillus niger. Using this method, it was shown that 2-deoxy-D-galactose markedly inhibits alpha 1,2-fucosylation. Measurement of the amount of 2-deoxy-D-galactose incorporated, however, showed that replacement of D-galactose by 2-deoxy-D-galactose does not entirely account for the decrease in alpha 1,2-fucosylation. In addition, a hitherto unreported compensatory increase of alpha 1,3/alpha 1,4-fucosylation was found to occur when alpha-1,2-fucosylation was inhibited by treatment with 2-deoxy-D-galactose.
Geilen
C C
CC
Institut für Molekularbiologie und Biochemie der Freien Universität Berlin, Germany.
Kannicht
C
C
Orthen
B
B
Heidrich
C
C
Paul
C
C
Grunow
D
D
Nuck
R
R
Reutter
W
W
D000255:Adenosine Triphosphate / Q000378:metabolism; D001201:Ascites / Q000378:metabolism; D002250:Carbon Radioisotopes; D006528:Carcinoma, Hepatocellular; D002460:Cell Line; D002462:Cell Membrane / Q000378:metabolism; D002846:Chromatography, Affinity; D002849:Chromatography, Gas; D002851:Chromatography, High Pressure Liquid; D005643:Fucose / Q000378:metabolism; D005690:Galactose / Q000031:analogs & derivatives* / Q000378:metabolism; D006801:Humans; D007700:Kinetics; D008113:Liver Neoplasms; D008562:Membrane Glycoproteins / Q000096:biosynthesis* / Q000302:isolation & purification; D011134:Polysaccharides / Q000096:biosynthesis / Q000302:isolation & purification; D011865:Radioisotope Dilution Technique; D014407:Tumor Cells, Cultured
D002250:Carbon Radioisotopes; D008562:Membrane Glycoproteins; D011134:Polysaccharides; D005643:Fucose; C019327:2-deoxy-lyxo-hexose; D000255:Adenosine Triphosphate; D005690:Galactose