Development of early mouse and rabbit embryos without zona pellucida

Twelve embryos, ranging from a four-celled stage to late unilaminar blastocysts, were obtained from the bandicoots I. macrourus and P. nasuta and examined by light and electron microscopy. These early stages covered at least one-quarter of the 12.5-day gestation period. The three non-cellular egg membranes characteristic of marsupials (zona pellucida, mucoid coat and shell membrane) were present, although the zona was sometimes absent or discontinuous in the intermediate and late unilaminar blastocysts examined. At the four-celled stage the blastomeres were close to the zona, but they had lost contact with each other, probably due to the extrusion of yolk, a phenomenon which has been described in other marsupials. The embryo did not increase in diameter until it was composed of at least 75 contiguous cells, which were in contact with the zona. In several of the larger blastocysts the protoderm cells had lost contact with the zona. Subsequently, the number of cells increased considerably and they were flattened against the egg membranes to form the late unilaminar blastocyst stage. Electron microscopy of the protoderm cells revealed the presence of numerous microvilli, particularly on the outer surface, and a range of other structures as great as those found in eutherian mammals. Remnants of spindle bridges were common in one 75-celled embryo. The yolk material in the blastocoele was also composed of a variety of structures, including small crystalloid inclusions composed of hexagonal units about 8-10 nm in diameter. Similar crystalloids have been described in the cells of early mouse and rabbit embryos and in egg and embryonic cells of various amphibians.

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Effect of Zona Pellucida Removal on DNA Methylation in Early Mouse Embryos1

Biology of Reproduction ◽

10.1095/biolreprod.105.046284 ◽

2006 ◽

Vol 74 (2) ◽

pp. 307-313 ◽

Cited By ~ 18

Author(s):

Ricardo C. Ribas ◽

Jane E. Taylor ◽

Caroline McCorquodale ◽

Ana C. Mauricio ◽

Mário Sousa ◽

...

Keyword(s):

Dna Methylation ◽

Zona Pellucida ◽

Early Mouse

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Cell-matrix interactions in the early mouse embryo

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100123404 ◽

1992 ◽

Vol 50 (1) ◽

pp. 600-601

Author(s):

A.E. Sutherland ◽

P.G. Calarco ◽

C.H. Damsky

Keyword(s):

Mouse Embryo ◽

Giant Cells ◽

Blastocyst Stage ◽

Integrin Subunit ◽

Β1 Integrin ◽

Cell Stage ◽

Early Mouse Embryo ◽

Migratory Activity ◽

Early Mouse ◽

Cell Matrix Interactions

Cell-extracellular matrix (ECM) interactions mediated by the integrin family of receptors are critical for morphogenesis and may also play a regulatory role in differentiation during early development. We have examined the onset of expression of individual integrin subunit proteins in the early mouse embryo, and their roles in early morphogenetic events. As detected by immunoprecipitation, the α6, αV, β1, and β3 subunits are detected as early as the 4-cell stage, α5 at the hatched blastocyst stage and αl and α3 following blastocyst attachment. We tested the role of these integrins in the attachment and migratory activity of two cell populations of the early mouse embryo: the trophoblast giant cells, which invade the uterine stroma and ultimately contribute to the chorio-allantoic placenta, and the parietal endoderm, which migrates over the inner surface of the trophoblast and ultimately forms Reichert's membrane and the parietal yolk sac. Experiments were done in serum-free medium on substrates coated with laminin (Ln) and fibronectin (Fn). Trophoblast outgrowth occurs on Ln and its E8 fragment (long arm), but not on the E1’ fragment (cross region) (Figs. 1, 2 ). This outgrowth is inhibited by anti-E8, anti-Ln, and by the anti-β1 family antiserum anti-ECMR, but not by anti-αV or the function-perturbing GoH3 antibody that recognizes the α6/β1 integrin, a major Ln (E8) receptor. This suggests that trophoblast outgrowth on Ln or E8 is mediated by a different β1 integrin such as α3/β1. Early stages of trophoblast outgrowth (up to 48 hours) on Fn are inhibited by anti-Fn and by function-perturbing anti-αV antibodies, whereas at later times outgrowth becomes insensitive to anti-αV but remains sensitive to the anti-β1 family antiserum anti-ECMr, indicating that trophoblast cells modulate their interaction with Fn during outgrowth. Trophoblast outgrowth on vitronectin (Vn) is sensitive to anti-αV antibodies throughout the 5-day period examined.

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Effectiveness of zona pellucida protein ZPB as an immunocontraceptive antigen

Reproduction ◽

10.1530/reprod/120.1.19 ◽

2000 ◽

pp. 19-32 ◽

Cited By ~ 19

Author(s):

ML Martinez ◽

JD Harris

Keyword(s):

Menstrual Cycle ◽

Recombinant Protein ◽

Antibody Titre ◽

Zona Pellucida ◽

Protein A ◽

Papio Cynocephalus ◽

Cynomolgus Monkeys ◽

Menstrual Cycles ◽

Normal Menstrual Cycle

Immunization of female mammals with native zona pellucida (ZP) proteins is known to cause infertility. Since each human ZP protein is now available as a purified recombinant protein, is it possible to compare the immunocontraceptive potential of each ZP protein. A breeding study was conducted in cynomolgus monkeys (Macaca fasicularis) after immunization with recombinant human ZP (rhZP) proteins (ZPA, ZPB, ZPC) separately and in combinations. This study demonstrated that immunization with recombinant human ZPB (rhZPB) protein caused cynomolgus monkeys to become infertile for 9-35 months. A second study was conducted in baboons (Papio cynocephalus), which yielded a similar result. The baboons immunized with rhZPB became infertile for 9 to > 20 months. During the time of maximum antibody titre, some animals experienced disruption of the menstrual cycle, but eventually all of the animals resumed normal menstrual cycles. Control animals and animals immunized with other rhZP proteins all became pregnant before any of the rhZPB-treated animals. This is the first study in which a recombinant ZP protein has consistently induced infertility in a primate without permanent disruption of the normal menstrual cycle.

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Reproductive characteristics of the african pygmy hedgehog, atelerix albiventris

Reproduction ◽

10.1530/reprod/120.1.143 ◽

2000 ◽

pp. 143-150 ◽

Cited By ~ 8

Author(s):

JM Bedford ◽

OB Mock ◽

SK Nagdas ◽

VP Winfrey ◽

GE Olson

Keyword(s):

Fallopian Tube ◽

Zona Pellucida ◽

Sperm Head ◽

Reproductive Characteristics ◽

Cumulus Oophorus ◽

The Matrix ◽

Main Components ◽

Initial Binding ◽

Structural Matrix

To obtain further perspective on reproduction and particularly gamete function among so-called primitive mammals presently grouped in the Order Insectivora, we have examined the African hedgehog, Atelerix albiventris, in light of unusual features reported in shrews and moles. Atelerix proves to share many but not all of the characteristics seen in these other insectivores. The penis of Atelerix has a 'snail-like' form, but lacks the surface spines common in insectivores and a number of other mammals. Hedgehog spermatozoa display an eccentric insertion of the tail on the sperm head, and they manifest the barbs on the perforatorium that, in shrews, probably effect the initial binding of the sperm head to the zona pellucida. As a possible correlate, the structural matrix of the hedgehog acrosome comprises only two main components, as judged by immunoblotting, rather than the complex of peptides seen in the matrix of some higher mammals. The Fallopian tube of Atelerix is relatively simple; it displays only minor differences in width and in the arborized epithelium between the isthmus and ampulla, and shows no evidence of the unusual sperm crypts that characterize the isthmus or ampulla, depending on the species, in shrews and moles. In common with other insectivores, Atelerix appears to be an induced ovulator, as judged by the ovulation of some 6-8 eggs by about 23 h after injection of hCG. The dense cumulus oophorus appeared to have little matrix, in keeping with the modest dimensions of the tubal ampulla and, while it was not quite as discrete as that of soricids, it did show the same insensitivity to 0.5% (w/v) ovine or bovine hyaluronidase.

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Differences between antigenic determinants of pig and cat zona pellucida proteins

Reproduction ◽

10.1530/reprod/119.1.15 ◽

2000 ◽

pp. 15-23 ◽

Cited By ~ 15

Author(s):

K Jewgenow ◽

M Rohleder ◽

I Wegner

Keyword(s):

In Vitro Fertilization ◽

Zona Pellucida ◽

Antigenic Determinants ◽

Vitro Fertilization ◽

Contraceptive Vaccine ◽

Sperm Binding ◽

Dependent Inhibition ◽

Dose Dependent Inhibition ◽

Dose Dependent

Despite many efforts, the control of reproduction in feral cat populations is still a problem in urban regions around the world. Immunocontraception is a promising approach; thus the present study examined the suitability of the widely used pig zona pellucida proteins (pZP) for contraception in feral domestic cats. Purified zona pellucida proteins obtained from pig and cat ovaries were used to produce highly specific antisera in rabbits. Antibodies against pZP raised in rabbits or lions were not effective inhibitors of either in vitro sperm binding (cat spermatozoa to cat oocytes) or in vitro fertilization in cats, whereas antibodies against feline zona pellucida proteins (fZP) raised in rabbits showed a dose-dependent inhibition of in vitro fertilization. Immunoelectrophoresis, ELISA and immunohistology of ovaries confirmed these results, showing crossreactivity of anti-fZP sera to fZP and to a lesser extent to pZP, but no interaction of anti-pZP sera with fZP. It is concluded that cat and pig zonae pellucidae express a very small number of shared antigenic determinants, making the use of pZP vaccine in cats questionable. A contraceptive vaccine based on feline zona pellucida determinants will be a better choice for the control of reproduction in feral cats if immunogenity can be achieved.

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Interspecific variation of zona pellucida glycoconjugates in several species of marsupial

Reproduction ◽

10.1530/reprod/119.1.111 ◽

2000 ◽

pp. 111-120 ◽

Cited By ~ 5

Author(s):

JA Chapman ◽

OW Wiebkin ◽

WG Breed

Keyword(s):

Glycine Max ◽

Sialic Acid ◽

Zona Pellucida ◽

Fluorescein Isothiocyanate ◽

Interspecific Variation ◽

Lectin Histochemistry ◽

Sialic Acids ◽

Arachis Hypogea ◽

Marsupial Species ◽

Similar Intensity

The zona pellucida glycoconjugate content of several marsupial species was investigated using differential lectin histochemistry. Ovaries from fat-tailed dunnarts, a southern brown bandicoot, grey short-tailed opossums, brushtail possums, ringtail possums, koalas and eastern grey kangaroos were fixed, embedded in paraffin wax, sectioned and stained with ten fluorescein isothiocyanate-conjugated lectins. Sections were also incubated with either neuraminidase or saponified, respectively, before incubation with the lectins to identify saccharide residues masked by sialic acids or O-acetyl groups on sialic acids. The zonae pellucidae surrounding the oocytes of the marsupials demonstrated interspecific variation in glycoconjugate content, with mannose-containing glycoconjugates exhibiting the greatest variation. Some of the zona pellucida glycoconjugates of all species, except those of the opossums, were masked by sialic acid with an increase in fluorescence with lectins from Arachis hypogea (PNA), and Glycine max (SBA), after desialylation. The disaccharide beta-galactose(1-4)N-acetyl-D-glucosamine appeared to be conformationally masked by O-acetyl groups of sialic acids in the zonae pellucidae of all species, with an increase in fluorescence with the lectin from Erythrina cristagalli (ECA), after saponification. Similar intensity and localization of beta-(1-4)-N-acetyl-D-glucosamine, as shown by staining of the lectin from Triticum vulgaris (WGA), to the inner and outer regions of the zona pellucida, were found to those reported in eutherian species. WGA fluorescence became uniform throughout the zonae pellucidae after saponification, indicating differential O-acetylation of sialic acids on the internal compartment of the zonae pellucidae.

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Effect of ornidazole on fertility of male rats: inhibition of a glycolysis-related motility pattern and zona binding required for fertilization in vitro

Reproduction ◽

10.1530/reprod/118.1.127 ◽

2000 ◽

pp. 127-135 ◽

Cited By ~ 23

Author(s):

W Bone ◽

NG Jones ◽

G Kamp ◽

CH Yeung ◽

TG Cooper

Keyword(s):

Zona Pellucida ◽

Glucose Utilization ◽

Cumulus Cells ◽

Glycolytic Enzyme ◽

Male Rats ◽

Fertilization In Vitro ◽

Swimming Pattern ◽

Principal Piece ◽

Free Media

The effects of the male antifertility agent ornidazole on glycolysis as a prerequisite for fertilization were investigated in rats. Antifertility doses of ornidazole inhibited glycolysis within mature spermatozoa as determined from the lack of glucose utilization, reduced acidosis under anaerobic conditions and reduced glycolytic enzyme activity. As a consequence, cauda epididymidal spermatozoa from ornidazole-fed rats were unable to fertilize rat oocytes in vitro, with or without cumulus cells, which was not due to transfer of an inhibitor in epididymal fluid with the spermatozoa. Under IVF conditions, binding to the zona pellucida was reduced in spermatozoa from ornidazole-fed males and the spermatozoa did not undergo a change in swimming pattern, which was observed in controls. The block to fertilization could be explained by the disruption of glycolysis-dependent events, since reduced binding to the zona pellucida and a lack of kinematic changes were demonstrated by control spermatozoa in glucose-free media in the presence of respiratory substrates. The importance of glycolysis for binding to, and penetration of, the zona pellucida, and hyperactivation in rats is discussed in relation to the glycolytic production of ATP in the principal piece in which local deprivation of energy may explain the reduced force of spermatozoa from ornidazole-fed males.

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