Structural Requirements for Sulfation of Asparagine-Linked Oligosaccharides of Lutropin

• Published in: Proceedings of the National Academy of Sciences - PNAS Vol. 82; no. 23; pp. 7850 - 7854
• Main Authors: Green, Eric D., Morishima, Chihiro, Boime, Irving, Baenziger, Jacques U.
• Format: Journal Article
• Language: English
• Published: Washington, DC National Academy of Sciences of the United States of America 01-12-1985; National Acad Sciences
• Subjects: Adenine Nucleotides - metabolism; Analytical, structural and metabolic biochemistry; Animals; Biological and medical sciences; Carbohydrate Sequence; Cattle; Cell free system; Enzymes; Fundamental and applied biological sciences. Psychology; Glycoproteins; Glycoproteins - metabolism; Hormones; Liver; Luteinizing Hormone - metabolism; Microsomes - metabolism; Oligosaccharides; Oligosaccharides - metabolism; Phosphoadenosine Phosphosulfate - metabolism; Pituitary Gland - metabolism; Placenta; Protein Processing, Post-Translational; Proteins; Structure-Activity Relationship; Substrate Specificity; Sulfates; Sulfation; Sulfotransferases; Sulfurtransferases - metabolism; Tissue Distribution; Ungulates; Pituitary hormone; Bovine; Animal; Oligosaccharide; Asparagine; Biosynthesis; Glycoprotein hormone; LH; Post translational modification; Sulfatation
• ISSN: 0027-8424; 1091-6490
• DOI: 10.1073/pnas.82.23.7850

Human and bovine pituitary glycoprotein hormones (lutropin, follitropin, and thyrotropin) contain varying amounts of N-acetylgalactosamine and sulfate. The sulfate on asparagine-linked oligosaccharides of bovine lutropin (bLH) is present exclusively on GalNAc in the sequence GalNAc(β 1-4)GlcNAc(β 1-2)Manα . We have examined the structural requirements for sulfation of bLH oligosaccharides by using a reconstituted cell-free system. After cleavage from the protein, oligosaccharides containing the sequence GalNAc(β 1-4)GlcNAc(β 1-2)Manα were sulfated by enzymes in pituitary membranes. Addition of one or two sulfates was observed, depending upon the number of GalNAc acceptor sites on the oligosaccharide. Neither GalNAc alone nor oligosaccharides devoid of GalNAc were sulfated. Membranes from placenta or liver did not sulfate oligosaccharides released from bLH, indicating that the sulfating activity is pituitary-specific. The lack of peptide dependence for sulfation, in conjunction with the oligosaccharide specificity, suggests that the sequence GalNAc(β 1-4)GlcNAc(β 1-2)Manα contains the recognition signal for the sulfotransferase(s).