Of poly-A-acetyllactosamine

Murata T, Honda H, Hattori T, Usui T. Enzymatic synthesis of poly-A -acetyllactosamines as potential substrates for 23. 

Analysis of glycopeptides of different cell type in culture has revealed that at least small amounts of poly-A-acetyllactosamine chains are present in all cell lines analyzed [39], Interestingly, in the cells of neural origin the poly-A-acetyllactosamine glycans were mainly of the linear type, whereas those of other cell types were mainly branched. 

Labelling of the cell surface of PC 12 pheochromocytoma cells for the presence of poly-A-acetyllactosamine chains identifies a restricted number of glycoproteins as carriers of these glycans (Fig. 7). Induced neuronal differentiation of the cells in culture... 

In granulocytes, no branching of poly-Al-acetyllactosamines is observed, a 1-3-Fucosyltrans-ferase-catalyzed modification of the linear chains leads to the Lewis x antigen. If a2-3-sia-lyltransferase acts before fucosylation, sialyl Lewis x is formed. These carbohydrate stmc-tures are involved in a number of cell-cell interactions during the inflammatory response and... 

The poly-iV-acetyllactosamine glycans were first discovered as constituents of N-glycans in erythrocytes [36] and teratocarcinoma cells [37], in which they represent a major fraction of the cell surface carbohydrates. In contrast, analysis of whole brain tissue does not indicate the presence of major amounts of poly-77-acetyllactosamine chains [15]. That poly-A -acetyllactosamine glycans do exist in brain tissue is suggested by their accumulation in GMl-gangliosidosis [38]. Small amounts are also present in the form of keratan sulfate as 0-mannose linked chains (see above). 

Fig. 5. Induction of poly-iV-acetyllactosamine expression in differentiating mouse neuroblastoma cells. N1E-115 neuroblastoma cells were grown in the undifferentiated form or induced to differentiate by serum starvation for ten days. The glycopeptides metabolically labelled with H-glucosamine were prepared by pronase digestion and fractionated by gel filtration on a column of Bio-Gel P-100. The poIy-fV-acetyllactosamine glycopeptides (poly-LacNAc) were eluted in the fractions indicated by the bar [39].

Pierce, M, J Arango (1986) Rous sarcoma virus-transformed baby hamster kidney cells express higher levels of asparagine-linked tri- and tetraantennary glycopeptides containing [GlcNAc-beta (1,6)Man-alpha (1,6)Man] and poly-A-acetyllactosamine sequences than baby hamster kidney cells. J Biol Chem 261 10772-10777... 

Kupper, C.E., Rosencrantz, R.R., Henssen, B., Pelantova, H., Thones, S., Drozdova, A., Kren, V., and Elling, L. (2012) Chemo-enzymatic modification of poly-N-acetyllactosamine (LacNAc) oligomers and N,N-diacetyllactosamine (LacDiNAc) based on galactose oxidase treatment. Beilstein J. Org. Chem., 8, 712-725. 

Feizi, T., E.F. Hounsell, J. Alais, A. Veyrieres, and S. David. 1992. Further definition of the size of the blood group-I antigenic determinant using a chemically synthesised octasaccharide of poly-N-acetyllactosamine type. Carbohyd. Res. 10 289-297. 

Do, K.-Y, Smith, D. F., and Cummings, R. D., 1990, LAMP-1 in Cho cells is a primary carrier of poly-N-acetyllactosamine chains and is bound preferentially by a mammalian S-type lectin, Biochem. Biophys. Res. Commun. 173 1123-1128. 

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