Maria Granovsky

Learn More
T-cell activation requires clustering of a threshold number of T-cell receptors (TCRs) at the site of antigen presentation, a number that is reduced by CD28 co-receptor recruitment of signalling proteins to TCRs. Here we demonstrate that a deficiency in beta1,6 N-acetylglucosaminyltransferase V (Mgat5), an enzyme in the N-glycosylation pathway, lowers(More)
The Golgi enzyme beta1,6 N-acetylglucosaminyltransferase V (Mgat5) is up-regulated in carcinomas and promotes the substitution of N-glycan with poly N-acetyllactosamine, the preferred ligand for galectin-3 (Gal-3). Here, we report that expression of Mgat5 sensitized mouse cells to multiple cytokines. Gal-3 cross-linked Mgat5-modified N-glycans on epidermal(More)
Golgi beta1,6N-acetylglucosaminyltransferase V (MGAT5) is required in the biosynthesis of beta1,6GlcNAc-branched N-linked glycans attached to cell surface and secreted glycoproteins. Amounts of MGAT5 glycan products are commonly increased in malignancies, and correlate with disease progression. To study the functions of these N-glycans in development and(More)
Glycosylation of glycoproteins and glycolipids is one of many molecular changes that accompany malignant transformation. GlcNAc-branched N-glycans and terminal Lewis antigen sequences have been observed to increase in some cancers, and to correlate with poor prognosis. Herein, we review evidence that beta1, 6GlcNAc-branching of N-glycans contributes(More)
N- and O-linked glycan structures of cell surface and secreted glycoproteins serve a variety of functions related to cell-cell communication in systems affecting development and disease. The more sophisticated N-glycan biosynthesis pathway of metazoans diverges from that of yeast with the appearance of the medial-Golgi beta-N-acetylglucosaminyltransferases(More)
To investigate the developmental role of complex N-linked oligosaccharides, we previously inactivated the mouse Mgat1 gene which encodes UDP-N-acetylglucosamine: alpha-3-D-mannoside beta-1,2-N-acetylglucosaminyltransferase I (GlcNAc-TI). Mgat1-null embryos developed morphogenic abnormalities by embryonic day (E) 9.5 and failed to survive beyond E10.5. Prior(More)
In order to investigate the role of the peptide moiety of glycoproteins in the control of O-glycan biosynthesis, UDPgalactose:glycoprotein-N-acetyl-D-galactosamine 3-beta-D-galactosyltransferase (core 1 beta 3-Gal-T) from rat liver was tested for its specificity towards GalNAc-containing glycopeptide substrates. Series of glycopeptides have been synthesized(More)
UDP-GlcNAc:Manalpha1-6Manbeta-R beta1-6-N-acetylglucosaminyltransferase V (GlcNAc-TV) and UDP-GlcNAc:Galbeta1-3GalNAc-R beta1-6-N-acetylglucosaminyltransferase (core 2 GlcNAc-T) are Golgi enzymes that catalyse the biosynthesis of beta1-6GlcNAc-branched intermediates in the N- and O-linked biosynthesis pathways, respectively. The activities of these enzymes(More)
BACKGROUND An infectious etiology for childhood acute lymphoblastic leukemia (ALL) has long been suspected, although the characteristics of the putative childhood ALL-inducing agent(s) remain a mystery. We describe the testing of ALL leukemia cells for the presence of DNA sequences of the polyomavirus family: JC virus, BK virus, and simian virus 40 (SV40).(More)
Glycoproteins in mammalian cells are modified with complex-type aspargine-linked glycans of variable chain lengths and composition. Observations of mice carrying mutations in glycosyltransferase genes imply that N-glycan structures regulate T-cell receptor clustering and hence sensitivity to agonists. We argue that the heterogeneity inherent in(More)