TY - JOUR
T1 - d-Galactosyltransferase and its endogenous substrates in chick embryo fibroblasts transformed by rous sarcoma virus
AU - Podolsky, Daniel K.
AU - Fournier, Deborah A.
AU - Isselbacher, Kurt J.
N1 - Funding Information:
by a grant (CA-31277) from the National Cancer Institute, National Institutes
PY - 1986/6/1
Y1 - 1986/6/1
N2 - UDP=d-galactose: 2-acetamido-2-deoxy-β-d-glucopyranosyl 4=β-d-galactosyltransferase (GalTase) activity was purified, from primary chick embryo fibroblast (CEF) transformed by a temperature-sensitive, Rous sarcoma virus mutant (CEF-RSV), by chromatography on an affinity resin prepared with monoclonal antibodies to GalTase. Cellular glycopeptides from CEF, as well as CEF-RSV, maintained at permissive (37°) [CEF-RSV (37°)] and nonpermissive temperatures (41°) [CEF-RSV (41°)], were solubilized and galactosylated in vitro by incubation with purified GalTase substrates, composed of at least six discrete complex glycopeptides having bi- to tetra-antennary structures. The glycopeptides isolated from transformed cells, CEF-RSV (37°), included the six types observed in nontransformed cells, but demonstrated alterations in their relative amounts, including an increase in the content of a glycopeptide containing 3 mannose and 4 glucosamine residues. Furthermore, two additional complex-type glycopeptides were isolated from CEF- but demonstrated alterations in their relative amounts, including an increase in the content of a glycopeptide containing 3 mannose and 4 glucosamine residues. Furthermore, two additional complex type glycopeptides were isolated from CEF-RSV (37°). These malignant transformation-related glycopeptides were partially characterized and found to represent tri- and tetra-antennary complex glycopeptides. Endogenous galactosylation appeared to have occurred in a branched, nonspecific manner in these transformed cell-derived glycopeptides. These findings indicate that transformed cells may contain a greater preponderance of more highly branched, complex oligosaccharides which are randomly galactosylated at non-reducing termini by cellular GalTase.
AB - UDP=d-galactose: 2-acetamido-2-deoxy-β-d-glucopyranosyl 4=β-d-galactosyltransferase (GalTase) activity was purified, from primary chick embryo fibroblast (CEF) transformed by a temperature-sensitive, Rous sarcoma virus mutant (CEF-RSV), by chromatography on an affinity resin prepared with monoclonal antibodies to GalTase. Cellular glycopeptides from CEF, as well as CEF-RSV, maintained at permissive (37°) [CEF-RSV (37°)] and nonpermissive temperatures (41°) [CEF-RSV (41°)], were solubilized and galactosylated in vitro by incubation with purified GalTase substrates, composed of at least six discrete complex glycopeptides having bi- to tetra-antennary structures. The glycopeptides isolated from transformed cells, CEF-RSV (37°), included the six types observed in nontransformed cells, but demonstrated alterations in their relative amounts, including an increase in the content of a glycopeptide containing 3 mannose and 4 glucosamine residues. Furthermore, two additional complex-type glycopeptides were isolated from CEF- but demonstrated alterations in their relative amounts, including an increase in the content of a glycopeptide containing 3 mannose and 4 glucosamine residues. Furthermore, two additional complex type glycopeptides were isolated from CEF-RSV (37°). These malignant transformation-related glycopeptides were partially characterized and found to represent tri- and tetra-antennary complex glycopeptides. Endogenous galactosylation appeared to have occurred in a branched, nonspecific manner in these transformed cell-derived glycopeptides. These findings indicate that transformed cells may contain a greater preponderance of more highly branched, complex oligosaccharides which are randomly galactosylated at non-reducing termini by cellular GalTase.
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U2 - 10.1016/S0008-6215(00)90380-X
DO - 10.1016/S0008-6215(00)90380-X
M3 - Article
C2 - 3015407
AN - SCOPUS:0022732228
SN - 0008-6215
VL - 149
SP - 225
EP - 239
JO - Carbohydrate Research
JF - Carbohydrate Research
IS - 1
ER -