Poly-N-acetyllactosamine glycans of cellular glycoproteins: predominance of linear chains in mouse neuroblastoma and rat pheochromocytoma cell lines.
To study the properties of protein-bound oligosaccharides in neuronally differentiating cells, two model systems were used: murine N1E-115 and N-18 neuroblastoma cells inducible by serum starvation and rat PC12 pheochromocytoma cells inducible by nerve growth factor. Glycopeptides were prepared from cells metabolically labeled with [3H]glucosamine and analyzed by gel filtration. The properties of the high-molecular-weight glycopeptides were studied using enzymatic digestion with neuraminidase and endo-beta-galactosidase. In contrast to other cell lines analyzed, the neuroblastoma and pheochromocytoma lines contained predominantly glycopeptides completely cleavable with endo-beta-galactosidase, which indicated that they were linear-type poly-N-acetyllactosamine glycans. The proportion of these linear chains in the high-molecular-weight fraction increased during neuronal differentiation in both cell systems. The linear nature of the glycans was also correlated with positive anti-i and negative anti-I reactivity of the cells in immunofluorescence microscopy. Specific cell surface labeling for poly-N-acetyllactosamine glycans and sodium dodecyl sulfate-polyacrylamide gel electrophoresis revealed several glycoprotein components, some of which showed changes during neuronal differentiation. The high proportion of linear poly-N-acetyllactosamine chains in these neuronal cell lines and its increase during neuronal differentiation suggests that these glycans may be a characteristic feature of neuronal or neuronally differentiating cells.
Spillmann
D
D
Finne
J
J
D000310:Adrenal Gland Neoplasms / Q000032:analysis*; D000818:Animals; D002460:Cell Line; D005455:Fluorescent Antibody Technique; D005910:Glioma / Q000032:analysis; D006023:Glycoproteins / Q000032:analysis*; D051379:Mice; D008970:Molecular Weight; D009447:Neuroblastoma / Q000032:analysis*; D009474:Neurons / Q000032:analysis; D010673:Pheochromocytoma / Q000032:analysis*; D011134:Polysaccharides / Q000032:analysis*; D051381:Rats
D006023:Glycoproteins; D011134:Polysaccharides; C037199:poly-N-acetyllactosamine