Identification and Characterization of De Novo-Synthesized Porcine Oviductal Secretory Proteins1

Abstract

Oviductal secretory products provide a biochemical environment important for establishment of pregnancy. A previous study identified three de novo-synthesized glycoproteins by one-dimensional SDS-PAGE as well as increased incorporation of [3H]Leu into secretory protein by whole oviduct and ampulla associated with proestrus, estrus, and metestrus only. Here, our objective was to further identify and characterize oviductal secretory proteins, specifically 115,000- and 85,000-Mr estrus-associated proteins (EAP). Two-dimensional SDS-PAGE resolved the 115,000-Mr protein into two proteins of 100,000 Mr, one basic and one acidic, and the 85,000-Mr protein into 75,000- and 85,000-Mr species (pI less than 4.0). Differential secretion of proteins between ampulla and isthmus was indicated. The 100,000-, 75,000-, and 85,000-Mr proteins were synthesized by ampulla during estrus but not by isthmus nor by uterine endometrium. De novo-synthesized EAP were labeled with glucosamine, Leu, and Met, and the 75,000-85,000-Mr proteins from ampulla and a 30,000-Mr family from isthmus were labeled with fucose. Inorganic [35S]sulfate labeled three EAP. Fractionation of culture medium by gel filtration demonstrated differences between products secreted by ampulla and isthmus and suggested that some EAP may be found as high-molecular weight forms in the native state. Results indicate that porcine oviductal tissue synthesizes specific EAP at the time of fertilization and early cleavage-stage embryonic development, that there are differences in the type and distribution of glycoproteins from ampulla and isthmus, and that post-translational modifications occur with the addition of glucosamine, fucose, and inorganic sulfate.

Mouse oviduct-specific glycoprotein is an egg-associated ZP3-independent sperm-adhesion ligand

“…Composed of two major domains, a catalytically inactive chitinase domain and a C-terminal O-glycosylation domain, OGP is expressed in response to estrogen stimulation in the oviduct of numerous mammals, including pig (Buhi et al, 1990), hamster (Robitaille et al, 1988), baboon (Boice et al, 1990), bovine , mice (Kapur and Johnson, 1985) and humans (Verhage et al, 1988). Co-incubation of OGP or media conditioned with OGP (i.e.…”

Oviductins possess chitinase‐ and mucin‐like domains: A lead in the search for the biological function of these oviduct‐specific ZP‐associating glycoproteins

“…Extensive charge heterogeneity is a common property of all oviductins hitherto characterized (see Table 2): the presence of predominantly acidic and basic isoelectric variants was also reported for the baboon , human (Rapisarda et al, 1993), and porcine (Buhi et al, 1990) that a protein with the PI of the a form can be generated from the p form (Malette and Bleau, 1993).…”

“…In this review, we present the complete amino acid sequence of the processed hamster oviductin polypeptide, critically examine the relationships between the biochemical and immunological characteristics of oviductin molecules from various species, and report on the striking finding of chitinase-like and Sermhr rich, repeated mucin-type units in these glycoprotein structures. Finally, we propose that oviductins might poten- Buhi et al, 1990, 1994Buhi et al, 1990 Malette and Bleau, 1993;Merlen et al, 1994 and 8.0 70.890d 7 Suzuki et al, 1994 aApparent molecular mass on reducing SDS-PAGE. bRefers to the number of potential sites of N-glycosylation.…”

“…Indeed, hamster oviductin was shown to consist of at least two principal charge isoforms, the a and p forms, that possess different levels of glycosylation (Malette and Bleau, 1993). We have recently proposed (Malette and Bleau, 1993) that the heterogeneity of hamster oviductin, also reported in other species (Gandolfi et al, 1989;Buhi et al, 1990;Boice et al, 1990a;Donnelly et al, 1991;Rapisarda et al, 1993), might target different populations of the glycosylated molecules to distinct cellular localizations.…”

“…Indeed, while it has been clearly demonstrated that some of these oviduct-specific secretory proteins are released in response to endogenous estrogen at estrus in the mouse (Horvat et al, 1992), sheep (Sutton et al, 1986;Murray, 19931, human (Verhage et al, 1988), cow (Malayer et al, 1988;Gerena and Killian, 1990; Abe et al, 1993b), baboon (Ver- , and gilt (Buhi et al, 1989(Buhi et al, , 1990 or in ovariectomized estrogen-treated animals (Oliphant et al, 1984b;Buhi et al, ,1992Murray, 1993;) the role of steroid sex hormones in the control of the secretion (Malette et al, 1994) or mRNA expression (Donnelly et al, 1991;Arias et al, 1994) of others seems to be different. Some of these oviduct-specific secretory glycoproteins possess the interesting properties of interaction with the zona pellucida (zp) and/or perivitelline (PV) space of the oocyte during its passage through the oviduct and remain associated with the embryo until implantation.…”