The glycoproteins of human neuroblastoma cells contain a high proportion of fucosyl residues linked alpha 1 leads to 3 to N- acetylglucosamine (Fuc alpha 1 leads to 3G1cNAc) on the oligosaccharide antennae. Only a limited number of human tumors share this feature although all tumors and transformed cell lines have in common glycoproteins which contain a high proportion of multiantennary oligosaccharides. In part A we will continue our studies using lectin binding properties and 500-MHz 1H-NMR to define the glycopeptide containing Fuc alpha 1 leads to 3G1cNAc. The studies of the relationship of Fuc alpha 1 leads to 3G1cNAc to neuroblastoma will be extended by use of molecular probes to the enzyme, beta- N-acetylglucosaminide alpha 1 leads to 3fucosyltransferase, which is responsible for the fucosyl residues in this specific linkage. The DNA probes will be used to address biological questions relating to human neuroblastoma including the mechanisms responsible for the increased activity of this enzyme and the apparent concerted action of the enzyme with the oncogene N-myc. The enzyme is already pruified to electrophoretic homogeneity and thus probes will be generated by two approaches and used to screen genomic or cDNA libraries: 1) preparation of antibodies to the pruified enzyme, and 2) synthesis of oligonucleotides which will be deduced from a partial amino acid sequence of the pruified enzyme. In part B we will address the multiantennary oligosaccharides. NIH 3T3 cells which have been transformed by transfection of human tumor DNA will be used. NIH 3T3 cells contain terminal alpha-galactosyl residues as shown by NMR and lectin affinity. After transformation, the alpha-galactosyl residues appear to be replaced by sialic acid. We will continue to study the glycopeptides from NIH 3T3 and alpha 1-1 cells by lectin affinity and NMR analysis. The studies will be extended to pruify beta-D- galactoside alpha 2 leads to 3 sialyltransferase which will be used to obtain the necessary probes as described above to screen a cDNA library in the event that these probes are not available from other investigators. To understand the regulation of these enzymes in tumor cells on the molecular level will contribute to understanding the role they play in neuroblastoma and other tumor cells. In addition, basic information will be obtained concerning the synthesis of glycoproteins.
