Abstract
OVGP1 is the major non-serum glycoprotein in the oviduct fluid at the time of fertilization and early embryo development. Its activity differs among species. Here, we show that the C-terminal region of recombinant OVGP1 regulates its binding to the extracellular zona pellucida and affects its activity during fertilization. While porcine OVGP1 penetrates two-thirds of the thickness of the zona pellucida, shorter OVGP1 glycoproteins, including rabbit OVGP1, are restricted to the outer one-third of the zona matrix. Deletion of the C-terminal region reduces the ability of the glycoprotein to penetrate through the zona pellucida and prevents OVGP1 endocytosis. This affects the structure of the zona matrix and increases its resistance to protease digestion. However, only full-length porcine OVGP1 is able to increase the efficiency rate of in vitro fertilization. Thus, our findings document that the presence or absence of conserved regions in the C-terminus of OVGP1 modify its association with the zona pellucida that affects matrix structure and renders the zona matrix permissive to sperm penetration and OVGP1 endocytosis into the egg.
Highlights
Corresponding to region A, region BD and region D which were inserted in-frame with mMBP
Consistent with the observation that the three putative N-glycosylation sites of OVGP1 are located in region A (NetNGlyc 1.0 Server), its N-glycosylation did not depend on the presence of the D region, as shown by the fact that full-length pig OVGP1 (pOVGP1) and pOVGP1ab displayed comparable molecular weight shifts upon digestion with N-Glycosidase-F (Fig. 1b)
Recombinant glycoproteins expressed in HEK 293T cells were purified by immobilized metal-affinity chromatography (IMAC) (Fig. 1b) and their identity was confirmed by mass spectrometry analysis (MS/MS) (Supplementary Material Fig. S3)
Summary
Corresponding to region A (pOVGP1a, lane 1), region BD (mMBP-pOVGP1bd, lane 2) and region D (mMBPpOVGP1d, lane 3) which were inserted in-frame with mMBP (lane 4). The C-terminal region has a low degree of identity (37–63%) and similarity (50–75%) as well as several insertions/deletions in its sequence. Region B shows low identity among different mammals and contains multiple insertions/deletions. Virtually nothing is known about the contribution of the different regions of OVGP1 to its biological activity, or whether the presence or absence of the C-terminus of OVGP1 affects its species-specific roles. For this reason, we examined, at both the molecular and physiological level the role of the C-terminal region of OVGP1 in fertilization
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
