Identification of a Sperm Penetration Factor in the Oviduct of the Golden Hamster1

Abstract

Previously, we found oviductal eggs to be significantly more penetrable and fertilizable in vitro than ovulated eggs collected from the ovarian bursa, while bursal eggs were comparable to mature (unovulated) follicular eggs. Incubation of follicular eggs with a soluble eluate of oviductal egg cumulus complexes (COF) increased sperm penetration: the activity was macromolecular, was destroyed at 56 degrees C, and was produced in the oviduct. We now report purification of this oviductal factor that enhances penetration of follicular eggs and have identified it as oviductin (OVN). Oviducts, 1-1.5 h post-LH from eCG-primed females, were homogenized and the cytosolic fraction was chromatographed on a Helix pomatia lectin affinity column; specific proteins were eluted with 0.2 M N-acetyl-D-galactosamine. Fractions were monitored by dot-blot assay using as the primary antibody monoclonal antibody (mAb) 1C4 against OVN. Proteins were resolved by one-dimensional SDS-gel electrophoresis, followed by electrotransfer and immunostaining of Western blots. OVN fractions were indexed to COF by quantitative dot-blot assay, and activity was bioassayed by penetration of follicular eggs within 1 h of coincubation with precapacitated sperm +/- factors: COF and BSA (high and low controls, respectively) and fractions from the lectin-isolated peak. The mean penetration rates for three isolations were 17 +/- 4.0a, 51.7 +/- 5.0b, and 49 +/- 2.7b% for BSA, COF, and column fractions, respectively (p < or = 0.05). Purified OVN bound to follicular zonae during culture. Acrosome-intact sperm heads bound OVN during 30 min of incubation both before (t = 0 h) and after capacitation (t = 5.5 h) (visualized by indirect immunofluorescence).(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

“…Nevertheless, successful fertilization in the physiological in vivo environment might be facilitated by oviductal glycoproteins (for review see Bavister, 1988). Indeed, Boatman and Magnoni (1994) have recently reported that the incubation of ovarian oocytes with purified hamster oviductin increases sperm penetration.…”

“…However, this report did not address the precise site of association of the oviductal glycoprotein with the spermatozoa. Indirect immunofluorescence studies using a specific MAb (Boatman and Magnoni, 1994) showed that purified hamster oviductin binds in vitro to homologous sperm on the acrosomal crescent, however neither hamster nor human oviductin were found to associate with human sperm using the same techniques (Reuter et al, 1994). In vitro incubation of [35S]methionine-labeled proteins synthesized by bovine oviduct cultures with bull spermatozoa followed by the analysis of the solubilized sperm membranes using autoradiography and immunoblotting revealed that bovine oviductin associates with the sperm membranes (King and Killian, 1994).…”

Antibodies against the C-terminal peptide of rabbit oviductin inhibit mouse early embryo development to pass 2-cell stage

“…In the future, gain-of-function experiments may help to confirm the importance of the Cterminal peptide of the rabbit oviductin in the development of early embryo. It was reported that oviductin has a function on fertilization [3], [4], [16], while our research suggested that oviductin also has a function on the release of early embryonic development block.…”

“…One thinks that the oviductins is necessary for the normal development of early embryos, the other thinks that the early embryo can develop normally in absence of oviductins, provided that the media were done more meticulously and the cultural environment is controlled more stringently. Recently there are many reports about the function of mammalian oviductins [1][2][3][4], but there is no report yet about any oviductin which has a definite function in the development of early embryo. In our previous studies, we have gained loss of function evidence to suggest that the rabbit 64 kDa oviductin has a function in overcoming the development block of early embryos in vitro.…”

Influence of Estrogen and Progesterone on Ultrastructural Indices of Oviductal Epithelium in Sexually Immature Mice

“…The oviduct serves as an optimal environment for the transport of gametes, fertilization and early development of embryo (Roblero and Garavagno 1979;Fisher et al 1982;Forceledo et al 1982;Fuentealba et al 1988;Nieder and Macon 1987;Abe et al 1995;Boatman and Magnoni 1995;Lapointe et al 1995;Kim et al 1996a). Moreover, papers concerned with cultivation of zygots together with the oviductal epithelial cells, refer to the importance of the oviducts, too (Sathananthan et al 1990;Takeuchi et al 1992).…”