An Estrogen-Dependent Glycoprotein is Synthesized and Released from the Oviduct in a Temporal- and Region-Specific Manner during Early Pregnancy in the Ewe1

Abstract

Administration of estradiol-17 beta (E) to ovariectomized (ovx) sheep results in the synthesis and release of an M(r) 90,000-92,000 glycoprotein into the oviductal lumen and into culture medium of ampullar explants (Biol Reprod 1992; 47:889-902). The objective of this study was to determine when and from what region of the oviduct the M(r) 90,000-92,000 glycoprotein is synthesized and released during early pregnancy. Estrous ewes were bred to intact rams of known fertility, and oviducts were obtained at estrus (Day 0) and at Days 1.5, 2, 3, 4, 6, and 16 of pregnancy. Pregnancy was verified by the presence of a fertilized egg or developing conceptus and a functional corpus luteum. Oviductal secretions were collected by flushing oviducts with saline and by explant culture. The oviductal fimbria, ampulla, and isthmus were individually cultured (24 h) in the presence of 3H-leucine (3H-leu) or 3H-glucosamine (3H-glcN). The presence of the M(r) 90,000-92,000 glycoprotein in oviductal flushings and culture medium was determined by fluorography and Western blotting. The M(r) 90,000-92,000 protein was present in SDS gels and blots of oviductal flushings from animals through Days 4-6 of pregnancy, but not in flushings from Day 16 pregnant animals or from ovx, untreated animals. This protein was present in 3H-leu- and 3H-glcN-labeled culture medium of the oviductal ampulla (Days 0, 1.5, 2, 3, 4, 6, and 16) and fimbria (Days 0, 1.5, 2, 3, and 4) during early pregnancy.(ABSTRACT TRUNCATED AT 250 WORDS)

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

“…This is in sharp contrast to what is observed in the sheep (Murray, 1993) and suggests that either the hamster glycoprotein is constitutively expressed and secreted or that the rate of turnover of the protein in the oviductal epithelium is longer that the estrus cycle itself. Castration of sexually mature female hamsters slightly reduces the immunodetection signal for oviductin in the oviduct epithelium and the administration of estradiol to prepubertal females obviously enhances its secretion (Malette et al, 1994).…”

“…In species such as the mouse (Kapur and Johnson, 1988), sheep (Gandolfi et al, 1991;Murray, 19921, and gilt (Buhi et al, 1993), immunocytolocalization of oviductin molecules appears to be restricted to the ampullary segment whereas it also occurs in the isthmic epithelium ofthe rabbit (Oliphant et al, 1984a) and baboon (Verhage et al, 1990) oviduct. The synthesis and secretion of sheep oviductin by the fimbrial segment of the oviduct were demonstrated by immunodetection of radiolabeled culture media of fimbrial explants resolved on Western blots (Murray, 1993), while the presence of mouse oviductin molecules into a subpopulation of the noncilated epithelial cells of the infundibulum was visualized using immunoelectron microscopy (Kapur and Johnson, 1988). lt remains to be determined whether bovine oviductin is secreted by the three oviductal segments (Boice et al, 1990a) or by the ampullar and fimbrial epithelia only (Abe et al, 1993b).…”

“…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.…”

Identification of differentially expressed genes in the oviduct of two rabbit lines divergently selected for uterine capacity using suppression subtractive hybridization

“…However, to our knowledge, this is the first study in which the expression of HSD17B4 has been described in the rabbit oviduct albeit the expression of other proteins of the same family has been identified (Krusche et al 2001). Taking into account the steroid inactivation role of the HSD17B4 protein, we could hypothesize that overexpression of HSD17B4 in the oviduct of L-line rabbits could modify the estrogen concentration, changing the oviduct fluid composition and subsequently affecting the early embryonic development (Murray 1993;Killian 2004;Gad et al 2011). Similarly, changes in steroid concentration could also modify the expression of PGR, causing the desynchronization of oviductal and uterine environments and affecting the posterior development and implantation of embryos (Gad et al 2011;Waclawik 2011).…”

Why doesn’t conventional IVF work in the horse? The equine oviduct as a microenvironment for capacitation/fertilization

“…Oestrogen-dependent oviduct secretory glycoprotein (OSG) or oviductin is a unique oviduct protein conserved across many mammalian species. OSG enhances sperm-oocyte binding and penetration through the zona pellucida, and also plays a role in early embryonic development (cattle: (Boice et al 1990); sheep: (Murray 1993); pig: (Kouba et al 2000)). However, when searching the equine genome Mugnier et al (2009a) were only able to find an OSG-like gene that included stop codons, which they concluded might be a pseudogene.…”