title: Branching beta 1-6N-acetylglucosaminetransferases and polylactosamine expression in mouse F9 teratocarcinoma cells and differentiated counterparts.
abstract: beta-All-trans-retinoic acid (RA)-induced endodermal differentiation of mouse F9 teratocarcinoma cells is accompanied by changes in glycoprotein glycosylation, including expression of i antigen (i.e. polylactosamine) and leukophytohemagglutinin-reactive oligosaccharides (i.e. -GlcNAc beta 1-6Man alpha 1-6-branched N-linked). We have used the F9 teratocarcinoma cells as a model to study developmental regulation of glycosyltransferase activities which are responsible for the biosynthesis of beta 1-6GlcNAc-branched N- and O-linked oligosaccharides and polylactosamine. Growth of F9 cells in the presence of 10(-6) M RA for 4 days increased core 2 GlcNAc transferase and GlcNAc transferase V activities by 13- and 6-fold, respectively, whereas the activities of GlcNAc transferase I, beta 1-3GlcNAc transferase (i), beta 1-4Gal transferase, and beta 1-3Gal transferase increased 2-4-fold. Induction of glycosyltransferase activities by RA was dose-dependent and showed a biphasic response with approximately half of the increase observed 3 days after RA treatment and the remainder occurred by day 4. PYS-2, a parietal endoderm cell line, showed levels of glycosyltransferase activities similar to those of RA-treated F9 cells. Glycosyltransferase activities in the RA-resistant F9 cell line (RA-3-10) were low and showed only a small induction by RA. These observations suggest that differentiation of F9 cells is closely associated with induction of multiple glycosyltransferase activities, with most pronounced increases in GlcNAc transferase V and 2',5'-tetradenylate (core 2) GlcNAc transferase. The increase in GlcNAc transferase V was also reflected by the 4-6-fold increase in the binding of 125I-leukophytohemagglutinin to several cellular glycoproteins, which occurred after 3 days of RA treatment. The endo-beta-galactosidase-sensitive polylactosamine content of membrane glycoproteins and, in particular, the LAMP-1 glycoprotein was markedly increased after RA treatment of F9 cells. Consistent with these observations, fucosylated polylactosamine (i.e. dimeric Lex) was also increased in RA-treated cells. Analysis of the aryl oligosaccharides produced by F9 cells cultured in the presence of aryl alpha-D-GalNAc showed that RA treatment enhanced the synthesis of disialyl core 2 O-linked oligosaccharides and increased the polylactosamine content of the aryl oligosaccharides by > 20-fold. The results suggest that differentiation of F9 cells into endoderm is closely associated with increased GlcNAc transferase V and core 2 GlcNAc transferase activities, enzymes which control the level of beta 1-6GlcNAc-branched N- and O-linked oligosaccharides, the preferred substrates for polylactosamine addition.
authors.affiliation: Samuel Lunenfeld Research Institute, Mt. Sinai Hospital, Toronto, Ontario, Canada.
authors.forename: M
authors.initials: M
authors.lastname: Heffernan
authors.forename: R
authors.initials: R
authors.lastname: Lotan
authors.forename: B
authors.initials: B
authors.lastname: Amos
authors.forename: M
authors.initials: M
authors.lastname: Palcic
authors.forename: R
authors.initials: R
authors.lastname: Takano
authors.forename: J W
authors.initials: JW
authors.lastname: Dennis
mesh_terms: D000606:Amino Sugars / Q000096:biosynthesis*; D000818:Animals; D002236:Carbohydrate Conformation; D002240:Carbohydrate Sequence; D002454:Cell Differentiation / Q000187:drug effects / Q000502:physiology*; D002851:Chromatography, High Pressure Liquid; D002852:Chromatography, Ion Exchange; D004797:Enzyme-Linked Immunosorbent Assay; D006602:Hexosyltransferases / Q000378:metabolism*; D007700:Kinetics; D051379:Mice; D008861:Microsomes / Q000378:metabolism; D008969:Molecular Sequence Data; D017351:N-Acetylglucosaminyltransferases / Q000378:metabolism*; D009844:Oligosaccharides / Q000096:biosynthesis / Q000302:isolation & purification; D011134:Polysaccharides / Q000096:biosynthesis*; D013724:Teratoma; D014212:Tretinoin / Q000494:pharmacology; D014407:Tumor Cells, Cultured; D001616:beta-Galactosidase / Q000378:metabolism
chemical_list: D000606:Amino Sugars; D009844:Oligosaccharides; D011134:Polysaccharides; C016735:sialooligosaccharides; C066929:polylactosamine; D014212:Tretinoin; D006602:Hexosyltransferases; D017351:N-Acetylglucosaminyltransferases; C024850:alpha-1,3-mannosyl-glycoprotein beta-1,2-N-acetylglucosaminyltransferase I; C052254:alpha-1,6-mannosylglycoprotein beta 1,6-N-acetylglucosaminyltransferase; D001616:beta-Galactosidase