Oviduct glycoprotein

Kdn-gp appeared to be synthesized during relatively later stages of oogenesis, since it was undetectable in the oocyte 3 months prior to ovulation. Although the cell types that synthesize Kdn-gp have not been identified, it is most likely synthesized under hormonal control in some extraoocj e cells (i.e. follicle cells), secreted and partly incorporated into the second outermost layer of the vitelline envelope just before ovulation. Kdn-gp may thus be a molecule homologous to the oviduct glycoproteins of mammals that are reported to be secreted and partly incorporated into the egg surface [58-60]. 

Buhi WC, Alvarez IM, Choi I, Cleaver BD, Simmen FA 1996 Molecular cloning and characterization of an estrogen-dependent porcine oviductal secretory glycoprotein. Biol Reprod 55 1305-1314... 

Malette, B., Paquette, Y., Merlen, Y. and Bleau, G. (1995) Oviductins possess chitinase and mucin-like domains a lead in the search for biological function of these oviduct-specific ZP-associating glycoproteins. Molecular Reproduction and Development 41, 384-397. 

Sendai, Y., Abe, H., Kikuchi, M., Satoh, T. and Hoshi, H. (1995) Purification and molecular cloning of bovine oviduct specific glycoprotein. Biology of Reproduction 50, 927-934. 

Secretion of nonglycosylated macromolecules in the presence of tunicamycin has also been investigated in a number of other cells. Rat-liver cell-secretion ol albumin (a carbohydrate-free protein), transferrin, and a-acid glycoprotein was not inhibited, and, in chick-liver cells, only a decrease by 10-25% in the secretion of transferrin and the apoprotein B chain of very-low-density lipoprotein was noted.463,464 The secretion of ovalbumin (a glycoprotein) from hen oviduct was not blocked by tunicamycin.465... 

Paul-Gardais, A., Picard, J., Hermelin, B. Turnover of sulfate in glycopeptides from egg shell membranes and hen oviduct sulfated glycoproteins. Biochim. Biophys. Acta 354, 11 (1974)... 

In contrast to sero- and lactotransferrins, glycans of ovotransferrins from avian egg-white contain a bisecting A-acetylglucosamine residue, like other glycoproteins from oviducts, such as ovomucoid and ovalbumin for instance (Fig. 16A-C). Like all of the avian egg glycoproteins, ovotransferrins are not fueosylated. 

I. Brockhausen, J. Carver, H. Schachter, Control of Glycoprotein Synthesis. XIV. The use of oligosaccharide substrates and HPLC to study the sequential pathway for N-acetylglucosa-minyltransferases I, II, III, IV, V and VI in the biosynthesis of highly branched N-glycans by hen oviduct membranes, Biochem Cell Biol, 1988, 66, 1134-1151. 

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