The egg coat zona pellucida 3 glycoprotein – evolution of its putative sperm-binding region in Old World murine rodents (Rodentia: Muridae)

In eutherian mammals, before fertilisation can occur the spermatozoon has to bind to, and penetrate, the egg coat, the zona pellucida (ZP). In the laboratory mouse there is good evidence that the primary sperm-binding site is a protein region encoded by Exon 7 of the ZP3 gene and it has been proposed that binding is species specific and evolves by sexual selection. In the present study we investigate these hypotheses by comparing Exon 6 and 7 sequences of ZP3 in 28 species of murine rodents of eight different divisions from Asia, Africa and Australasia, in which a diverse array of sperm morphologies occurs. We found considerable nucleotide (and corresponding amino acid) sequence divergence in Exon 7, but not in Exon 6, across these species, with evidence for positive selection at five codon positions. This molecular divergence does not appear to be due to reinforcement to reduce hybridisation, nor does it correlate with divergence in sperm head morphology or tail length, thus it is unlikely to be driven by inter-male sperm competition. Other forms of post-copulatory sexual selection therefore appear to have resulted in the molecular divergence of this region of ZP3 in this highly speciose group of mammals.

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Sperm morphology of the Rattini – are the interspecific differences due to variation in intensity of intermale sperm competition?

Reproduction Fertility and Development ◽

10.1071/rd17431 ◽

2018 ◽

Vol 30 (11) ◽

pp. 1434 ◽

Cited By ~ 4

Author(s):

Tessa Pahl ◽

Hanna J. McLennan ◽

Yun Wang ◽

Anang S. Achmadi ◽

Kevin C. Rowe ◽

...

Keyword(s):

Sexual Selection ◽

Sperm Competition ◽

Sperm Morphology ◽

Tail Length ◽

Sperm Head ◽

Apical Hook ◽

Interspecific Differences ◽

Murine Rodent ◽

Murine Rodents ◽

Sperm Size

It is widely accepted that in mammals a causal relationship exists between postcopulatory sexual selection and relative testes mass of the species concerned, but how much it determines sperm size and shape is debatable. Here we detailed for the largest murine rodent tribe, the Rattini, the interspecific differences in relative testes mass and sperm form. We found that residual testes mass correlates with sperm head apical hook length as well as its angle, together with tail length, and that within several lineages a few species have evolved highly divergent sperm morphology with a reduced or absent apical hook and shorter tail. Although most species have a relative testes mass of 1–4%, these derived sperm traits invariably co-occur in species with much smaller relative testes mass. We therefore suggest that high levels of intermale sperm competition maintain a sperm head with a long apical hook and long tail, whereas low levels of intermale sperm competition generally result in divergent sperm heads with a short or non-existent apical hook and shorter tail. We thus conclude that sexual selection is a major selective force in driving sperm head form and tail length in this large tribe of murine rodents.

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Molecular evolution of the carboxy terminal region of the zona pellucida 3 glycoprotein in murine rodents

Reproduction ◽

10.1530/rep-06-0043 ◽

2007 ◽

Vol 133 (4) ◽

pp. 697-708 ◽

Cited By ~ 12

Author(s):

Christine A Swann ◽

Steven J B Cooper ◽

William G Breed

Keyword(s):

Positive Selection ◽

Zona Pellucida ◽

Laboratory Mouse ◽

Sequence Diversity ◽

Murine Rodents ◽

Selective Forces ◽

Carboxy Terminal Region ◽

Low Levels ◽

Species Specific ◽

Carboxy Terminal

In mammals, before fertilization can occur, sperm have to bind to, and penetrate, the zona pellucida (ZP). In the laboratory mouse, which has been used as a model system for fertilization studies, sperm–ZP binding has been found to be mediated by a region at the carboxy terminal, encoded by exon 7 of theZp3gene. This region shows considerable interspecific sequence diversity with some evidence of adaptive evolution in mammals, suggesting that it may contribute to species-specific sperm–ZP binding. However, in a previous study of sequence diversity of ZP3 of three species of Australian murine rodents, we found an identical protein sequence of the region encoded by exon 7. Here, we expand this earlier study to determine the sequence diversity of this region in 68 out of the 130 species of Australasian murine rodents. Maximum likelihood analyses, using representatives of both New Guinean and Australian taxa, provide evidence of positive selection at three codons adjacent to, or within, the putative combining-site for sperm of ZP3, but this was not evident when the analysis was restricted to the Australian taxa. The latter group showed low levels of both intra- and inter-generic sequence divergences in the region encoded by exon 7 of Zp3, with little evidence that this region contributes to species specificity of sperm–ZP binding. These findings suggest that the selective forces acting on theZp3exon 7 region during the evolution of the Australasian murine rodents have been variable, and that positive selection has only occurred in a few lineages.

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ZP4 Is Present in Murine Zona Pellucida and Is Not Responsible for the Specific Gamete Interaction

Frontiers in Cell and Developmental Biology ◽

10.3389/fcell.2020.626679 ◽

2021 ◽

Vol 8 ◽

Author(s):

Mª José Izquierdo-Rico ◽

Carla Moros-Nicolás ◽

Míriam Pérez-Crespo ◽

Ricardo Laguna-Barraza ◽

Alfonso Gutiérrez-Adán ◽

...

Keyword(s):

Animal Model ◽

Zona Pellucida ◽

Acrosome Reaction ◽

Functional Roles ◽

Sperm Binding ◽

The Status ◽

Murine Rodents ◽

Mouse Species ◽

Mammalian Eggs

Mammalian eggs are surrounded by an extracellular matrix called the zona pellucida (ZP). This envelope participates in processes such as acrosome reaction induction, sperm binding, protection of the oviductal embryo, and may be involved in speciation. In eutherian mammals, this coat is formed of three or four glycoproteins (ZP1–ZP4). While Mus musculus has been used as a model to study the ZP for more than 35 years, surprisingly, it is the only eutherian species in which the ZP is formed of three glycoproteins Zp1, Zp2, and Zp3, Zp4 being a pseudogene. Zp4 was lost in the Mus lineage after it diverged from Rattus, although it is not known when precisely this loss occurred. In this work, the status of Zp4 in several murine rodents was tested by phylogenetic, molecular, and proteomic analyses. Additionally, assays of cross in vitro fertilization between three and four ZP rodents were performed to test the effect of the presence of Zp4 in murine ZP and its possible involvement in reproductive isolation. Our results showed that Zp4 pseudogenization is restricted to the subgenus Mus, which diverged around 6 MYA. Heterologous in vitro fertilization assays demonstrate that a ZP formed of four glycoproteins is not a barrier for the spermatozoa of species with a ZP formed of three glycoproteins. This study identifies the existence of several mouse species with four ZPs that can be considered suitable for use as an experimental animal model to understand the structural and functional roles of the four ZP proteins in other species, including human.

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Egg cortical granule N-acetylglucosaminidase is required for the mouse zona block to polyspermy.

The Journal of Cell Biology ◽

10.1083/jcb.123.6.1431 ◽

1993 ◽

Vol 123 (6) ◽

pp. 1431-1440 ◽

Cited By ~ 87

Author(s):

D J Miller ◽

X Gong ◽

G Decker ◽

B D Shur

Keyword(s):

Zona Pellucida ◽

Binding Sites ◽

Binding Activity ◽

Cortical Granule ◽

Cortical Granules ◽

Sperm Binding ◽

Competitive Inhibitors ◽

Glycosidase Inhibitor ◽

Egg Coat

The mammalian egg must be fertilized by only one sperm to prevent polyploidy. In most mammals studied to date, the primary block to polyspermy occurs at the zona pellucida, the mammalian egg coat, after exocytosis of the contents of the cortical granules into the perivitelline space. The exudate acts on the zona, causing it to lose its ability to bind sperm and to be penetrated by sperm previously bound to the zona. However, the cortical granule components responsible for the zona block have not been identified. Studies described herein demonstrate that N-acetylglucosaminidase is localized in cortical granules and is responsible for the loss in sperm-binding activity leading to the zona block to polyspermy. Before fertilization, sperm initially bind to the zona by an interaction between sperm surface GalTase and terminal N-acetylglucosamine residues on specific oligosaccharides of the zona glycoprotein ZP3 (Miller, D. J., M. B. Macek, and B. D. Shur. 1992. Nature (Lond.). 357:589-593). These GalTase-binding sites are lost from ZP3 after fertilization, an effect that can be duplicated by N-acetylglucosaminidase treatment. Therefore, N-acetylglucosaminidase, or a related glycosidase, may be present in cortical granules and be responsible for ZP3's loss of sperm-binding activity at fertilization. Of eight glycosidases assayed in exudates of ionophore-activated eggs, N-acetylglucosaminidase was 10-fold higher than any other activity. The enzyme was localized to cortical granules using immunoelectron microscopy. Approximately 70 or 90% of the enzyme was released from cortical granules after ionophore activation or in vivo fertilization, respectively. The isoform of N-acetylglucosaminidase found in cortical granules was identified as beta-hexosaminidase B, the beta, beta homodimer. Inhibition of N-acetylglucosaminidase released from activated eggs, with either competitive inhibitors or with specific antibodies, resulted in polyspermic binding to the zona pellucida. Another glycosidase inhibitor or nonimmune antibodies had no effect on sperm binding to activated eggs. Therefore, egg cortical granule N-acetylglucosaminidase is released at fertilization, where it inactivates the sperm GalTase-binding site, accounting for the block in sperm binding to the zona pellucida.

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Cryo-EM Structure of Native Human Uromodulin, a Zona Pellucida Module Polymer

10.1101/2020.05.28.119206 ◽

2020 ◽

Cited By ~ 1

Author(s):

Alena Stsiapanava ◽

Chenrui Xu ◽

Martina Brunati ◽

Sara Zamora-Caballero ◽

Céline Schaeffer ◽

...

Keyword(s):

Electron Microscopy ◽

Zona Pellucida ◽

Binding Sites ◽

Lateral Interaction ◽

Biological Processes ◽

Binding Region ◽

Sperm Binding ◽

Cryo Electron Microscopy ◽

Uropathogenic Bacteria ◽

Egg Coat

SUMMARYAssembly of extracellular filaments and matrices mediating fundamental biological processes such as morphogenesis, hearing, fertilization and antibacterial defense is driven by a ubiquitous polymerization module known as zona pellucida (ZP) “domain”. Despite the conservation of this element from hydra to human, no information is available on the filamentous conformation of any ZP module protein. Here we report the cryo-electron microscopy structure of uromodulin (UMOD)/Tamm-Horsfall protein, the most abundant protein in human urine and an archetypal ZP module-containing molecule, in its mature homopolymeric state. UMOD forms a one-start helix with an unprecedented 180-degree twist between subunits enfolded by interdomain linkers that have completely reorganized as a result of propeptide dissociation. Lateral interaction between filaments in the urine generates sheets exposing a checkerboard of binding sites to capture uropathogenic bacteria, and UMOD-based models of mammalian and avian heteromeric egg coat filaments identify a common sperm-binding region at the interface between subunits.

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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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