Biochemical characterization of a bovine oviduct-specific sialo-glycoprotein that sustains sperm viability in vitro.
A bovine oviduct-specific glycoprotein (BOGP) that sustained the viability of bovine spermatozoa in vitro was purified from an extract of bovine oviducts. The amino-terminal amino acid sequence of BOGP was found to be a homologous with that of oviductin, a protein from hamster that was recently characterized by Mallete and Bleau (1993: Biochem. J. 295, 437-445). Purified BOGP was characterized as a sialo-glycoprotein containing N-linked and O-linked sialo-oligosaccharides side chains with galactose, mannose, N-acetyl-D-galactosamine, N-acetyl-D-glucosamine, fucose and sialic acids in its core protein (57 kDa). Intact BOGP has a wide range of isoelectric points (pIs) from 6.5 to 3.0 but a narrow range of molecular masses around 95 kDa. On isoelectric focusing of neuraminidase-treated BOGP (AS-BOGP), a narrow band with a pI of 9.3 was observed, and the ability of AS-BOGP to maintain sperm viability was negligible. We propose that BOGP is a mucin-type sialo-glycoprotein with a molecular mass of 72 kDa that contains one N-linked and approx. 15 O-linked sialo-oligosaccharide chains. These side chains appear to be important for the maintenance of sperm viability.
Satoh
T
T
Research Institute for the Functional Peptides, Yamagata, Japan.
Abe
H
H
Sendai
Y
Y
Iwata
H
H
Hoshi
H
H
D000595:Amino Acid Sequence; D000818:Animals; D002417:Cattle; D002470:Cell Survival; D005187:Fallopian Tubes / Q000737:chemistry*; D005260:Female; D008297:Male; D008969:Molecular Sequence Data; D009844:Oligosaccharides / Q000032:analysis; D017386:Sequence Homology, Amino Acid; D012697:Serine Endopeptidases / Q000737:chemistry*; D012795:Sialoglycoproteins / Q000737:chemistry* / Q000494:pharmacology* / Q000502:physiology; D013094:Spermatozoa / Q000187:drug effects* / Q000502:physiology
D009844:Oligosaccharides; D012795:Sialoglycoproteins; D012697:Serine Endopeptidases; C074599:oviductin