TY - JOUR
T1 - Biosynthesis of sulfated asparagine-linked oligosaccharide on bovine lutropin
AU - Green, E. D.
AU - Boimes, I.
AU - Baenziger, J. U.
PY - 1986
Y1 - 1986
N2 - The asparagine-linked oligosaccharides on bovine lutropin (bLH) are unusual, containing GalNAc and sulfate but no galactose or sialic acid. Oligosaccharides from metabolically radiolabeled or purified bLH consist of non- (neutral), mono- (S-1), and di- (S-2) sulfated structures. We have previously shown that S-2 is a complex type oligosaccharide bearing two peripheral branches with the sequence SO4→GalNAc→GlcNAc attached to a typical Man3GlcNAc2 core (Green, E.D., van Halbeek, H., Boime, I., and Baenziger, J.U. (1985) J. Biol. Chem. 260, 15623-15630). We have now characterized the S-1 oligosaccharides on bLH which, in contrast to S-2, consist of several different structures of both the hybrid and complex types. The sulfate on S-1 oligosaccharides is located exclusively within the peripheral sequence SO4→GalNAc→GlcNAc. The GalNAc bearing hybrid structures, either with or without sulfate, cannot be processed to mono- or disulfated complex oligosaccharides due to the inability of either α-mannosidase II or GlcNAc-transferase II to act on GalNAc containing oligosaccharides. Since both Gal and GalNAc are added to oligosaccharides on some pituitary hormones, for example bovine and ovine follitropin and human lutropin, the Gal- and GalNAc-transferase appear to be key elements in regulating the synthesis of sulfated oligosaccharides on bLH and the other pituitary glycoprotein hormones.
AB - The asparagine-linked oligosaccharides on bovine lutropin (bLH) are unusual, containing GalNAc and sulfate but no galactose or sialic acid. Oligosaccharides from metabolically radiolabeled or purified bLH consist of non- (neutral), mono- (S-1), and di- (S-2) sulfated structures. We have previously shown that S-2 is a complex type oligosaccharide bearing two peripheral branches with the sequence SO4→GalNAc→GlcNAc attached to a typical Man3GlcNAc2 core (Green, E.D., van Halbeek, H., Boime, I., and Baenziger, J.U. (1985) J. Biol. Chem. 260, 15623-15630). We have now characterized the S-1 oligosaccharides on bLH which, in contrast to S-2, consist of several different structures of both the hybrid and complex types. The sulfate on S-1 oligosaccharides is located exclusively within the peripheral sequence SO4→GalNAc→GlcNAc. The GalNAc bearing hybrid structures, either with or without sulfate, cannot be processed to mono- or disulfated complex oligosaccharides due to the inability of either α-mannosidase II or GlcNAc-transferase II to act on GalNAc containing oligosaccharides. Since both Gal and GalNAc are added to oligosaccharides on some pituitary hormones, for example bovine and ovine follitropin and human lutropin, the Gal- and GalNAc-transferase appear to be key elements in regulating the synthesis of sulfated oligosaccharides on bLH and the other pituitary glycoprotein hormones.
UR - http://www.scopus.com/inward/record.url?scp=0022884332&partnerID=8YFLogxK
M3 - Article
C2 - 2946684
AN - SCOPUS:0022884332
SN - 0021-9258
VL - 261
SP - 16309
EP - 16316
JO - Journal of Biological Chemistry
JF - Journal of Biological Chemistry
IS - 35
ER -