Cell Surface Glycoprotein and Asparagine-linked Sugar Chain Patterns of Rat Erythroleukemic Cell Lines¹

In order to elucidate whether chromosomal change or induction of differentiation is correlated with the change of the patterns of cell surface glycoproteins and asparagine-linked sugar chains, glycoproteins and carbohydrates of five rat erythroleukemic cell lines (K1DB, D5A1, K2D, K2DA, and K4D) were studied by sodium dodecyl sulfate:polyacrylamide gel electrophoresis and hydrazinolysis followed by gel chromatography, respectively. The surface glycoprotein patterns of five cell lines were very similar, each containing four glycoproteins with molecular weights of 250,000, 115,000, 80,000, and 28,000, respectively. Only D5A1, which can be induced to erythroid differentiation, had two additional glycoproteins, with molecular weights of 135,000 and 65,000, respectively. All neutral oligosaccharides obtained from plasma membranes of five cell lines by hydrazinolysis were of the high-mannose type, and the acidic oligosaccharides were of the complex type with three different types of outer chains in various combinations: ±NeuAcα2 → 6Galβ1 → 4GlcNAc; Galβ1 → 3Galβ1 → 4GlcNAc; and Galβ1 → 4GlcNAcβ1 → 3Galβ1 → 4GlcNAc. An interesting finding was that two sugar chains, NeuAcα2 → 6Galβ1 → 4GlcNAcβ1 → 2Manα1 → 3(Galβ1 → 4GlcNAcβ1 → 2Manα1 → 6)Manβ1 → 4GlcNAcβ1 → 4(±Fucα1 → 6)GlcNAc_OT (in which the subscript OT indicates a NaB³H₄-reduced oligosaccharide), were found only in surface carbohydrates of D5A1.