title: Transient expression of sialylated glycans during glycoprotein processing by embryonal carcinomas.
abstract: Embryonal carcinoma and early embryonic cells express unusually large and complex carbohydrates on their surfaces that are lost during differentiation. These carbohydrates are composed of alternating galactose and N-acetylglucosamine residues and have either linear or branched architectures. Compared to the glycans expressed by many differentiated cells these glycans are poorly sialylated. However, metabolic studies reveal that there is a transient expression of sialylated glycans during the processing of glycoproteins by embryonal carcinomas. After a short pulse with mannose the major complex-type glycan is a biantennary glycan with two sialic acids. During subsequent chase periods this glycan species is replaced by unsialylated glycans that have elongated branches composed of alternating galactose and N-acetylglucosamine residues.
mesh_terms: D000818:Animals; D003208:Concanavalin A / Q000378:metabolism; D054278:Embryonal Carcinoma Stem Cells; D006023:Glycoproteins / Q000378:metabolism*; D051379:Mice; D019158:N-Acetylneuraminic Acid; D014411:Neoplastic Stem Cells / Q000378:metabolism*; D009439:Neuraminidase / Q000494:pharmacology; D011134:Polysaccharides / Q000378:metabolism*; D012794:Sialic Acids / Q000378:metabolism*
chemical_list: D006023:Glycoproteins; D011134:Polysaccharides; D012794:Sialic Acids; D003208:Concanavalin A; D009439:Neuraminidase; D019158:N-Acetylneuraminic Acid