Sperm Membrane and Zona Pellucida Interactions during Fertilization

Egg zona pellucida glycoproteins mZP3 and mZP2 serve as primary and secondary sperm receptors, respectively, during initial stages of fertilization in mice [Wassarman (1988) A. Rev. Biochem. 57, 415–442]. These receptors interact with complementary egg-binding proteins (EBPs) located on the sperm surface to support species-specific gamete adhesion. Results of whole-mount autoradiographic experiments suggest that purified egg mZP3 and mZP2 bind preferentially to acrosome-intact (AI) and acrosome-reacted (AR) sperm heads, respectively [Bleil and Wassarman (1986) J. Cell Biol. 102, 1363–1371]. Here, we used purified egg mZP2, egg mZP3 and fetuin, which were coupled directly to colloidal gold (‘gold-probes’), to examine binding of these glycoproteins to membrane compartments of AI and AR sperm by transmission electron microscopy. mZP3 gold-probes were found associated primarily with plasma membrane overlying the acrosomal and post-acrosomal regions of AI sperm heads. They were also found associated with plasma membrane overlying the post-acrosomal region of AR sperm heads. mZP2 gold-probes were found associated primarily with inner acrosomal membrane of AR sperm heads, although some gold was associated with outer acrosomal membrane of AI sperm that had holes in plasma membrane overlying the acrosome. Fetuin gold-probes, used to assess background levels of binding, were bound at relatively low levels to plasma membrane and inner acrosomal membrane of AI and AR sperm, respectively. None of the gold-probes exhibited significant binding to sperm tails, or to red blood cells and residual bodies present in sperm preparations. These results provide further evidence that mZP2 and mZP3 bind preferentially to heads of AR and AI sperm, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

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Sperm Membrane Potential: Hyperpolarization during Capacitation Regulates Zona Pellucida-Dependent Acrosomal Secretion

Developmental Biology ◽

10.1006/dbio.1995.1304 ◽

1995 ◽

Vol 171 (2) ◽

pp. 554-563 ◽

Cited By ~ 144

Author(s):

Yang Zeng ◽

Edward N. Clark ◽

Harvey M. Florman

Keyword(s):

Membrane Potential ◽

Zona Pellucida ◽

Sperm Membrane

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Inhibition of mouse acrosome reaction and sperm-zona pellucida binding by anti-human sperm membrane protein 1 antibody

Asian Journal of Andrology ◽

10.1111/j.1745-7262.2007.00247.x ◽

2007 ◽

Vol 9 (1) ◽

pp. 23-29 ◽

Cited By ~ 9

Author(s):

Guo-Yan Cheng ◽

Jian-Li Shi ◽

Min Wang ◽

Yan-Qin Hu ◽

Chun-Meng Liu ◽

...

Keyword(s):

Membrane Protein ◽

Zona Pellucida ◽

Acrosome Reaction ◽

Human Sperm ◽

Sperm Membrane

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ZP3-dependent activation of sperm cation channels regulates acrosomal secretion during mammalian fertilization.

The Journal of Cell Biology ◽

10.1083/jcb.134.3.637 ◽

1996 ◽

Vol 134 (3) ◽

pp. 637-645 ◽

Cited By ~ 96

Author(s):

C Arnoult ◽

Y Zeng ◽

H M Florman

Keyword(s):

Membrane Potential ◽

Pertussis Toxin ◽

Zona Pellucida ◽

Mammalian Sperm ◽

Transient Rise ◽

Transduction Mechanisms ◽

Dependent Signal ◽

Sperm Membrane ◽

Mammalian Fertilization

The sperm acrosome reaction is a Ca(2+)-dependent secretory event required for fertilization. Adhesion to the egg's zona pellucida promotes Ca2+ influx through voltage-sensitive channels, thereby initiating secretion. We used potentiometric fluorescent probes to determine the role of sperm membrane potential in regulating Ca2+ entry. ZP3, the glycoprotein agonist of the zona pellucida, depolarizes sperm membranes by activating a pertussis toxin-insensitive mechanism with the characteristics of a poorly selective cation channel. ZP3 also activates a pertussis toxin-sensitive pathway that produces a transient rise in internal pH. The concerted effects of depolarization and alkalinization open voltage-sensitive Ca2+ channels. These observations suggest that mammalian sperm utilize membrane potential-dependent signal transduction mechanisms and that a depolarization pathway is an upstream transducing element coupling adhesion to secretion during fertilization.

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TMEM95 is a sperm membrane protein essential for mammalian fertilization

eLife ◽

10.7554/elife.53913 ◽

2020 ◽

Vol 9 ◽

Cited By ~ 5

Author(s):

Ismael Lamas-Toranzo ◽

Julieta G Hamze ◽

Enrica Bianchi ◽

Beatriz Fernández-Fuertes ◽

Serafín Pérez-Cerezales ◽

...

Keyword(s):

Membrane Protein ◽

Membrane Fusion ◽

Zona Pellucida ◽

Sperm Protein ◽

Egg Protein ◽

Egg Membrane ◽

Sperm Membrane ◽

Mammalian Fertilization ◽

Male Specific ◽

Mechanical Injection

The fusion of gamete membranes during fertilization is an essential process for sexual reproduction. Despite its importance, only three proteins are known to be indispensable for sperm-egg membrane fusion: the sperm proteins IZUMO1 and SPACA6, and the egg protein JUNO. Here we demonstrate that another sperm protein, TMEM95, is necessary for sperm-egg interaction. TMEM95 ablation in mice caused complete male-specific infertility. Sperm lacking this protein were morphologically normal exhibited normal motility, and could penetrate the zona pellucida and bind to the oolemma. However, once bound to the oolemma, TMEM95-deficient sperm were unable to fuse with the egg membrane or penetrate into the ooplasm, and fertilization could only be achieved by mechanical injection of one sperm into the ooplasm, thereby bypassing membrane fusion. These data demonstrate that TMEM95 is essential for mammalian fertilization.

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Mice expressing aberrant sperm-specific protein PMIS2 produce normal-looking but fertilization-incompetent spermatozoa

Molecular Biology of the Cell ◽

10.1091/mbc.e11-12-1025 ◽

2012 ◽

Vol 23 (14) ◽

pp. 2671-2679 ◽

Cited By ~ 30

Author(s):

Ryo Yamaguchi ◽

Yoshitaka Fujihara ◽

Masahito Ikawa ◽

Masaru Okabe

Keyword(s):

Zona Pellucida ◽

Cumulus Cells ◽

Specific Protein ◽

Aberrant Expression ◽

Sperm Transport ◽

Vitro Fertilization ◽

Sperm Binding ◽

Sperm Membrane ◽

Domain 3

Eight kinds of gene-disrupted mice (Clgn, Calr3, Pdilt, Tpst2, Ace, Adam1a, Adam2, and Adam3) show impaired sperm transition into the oviducts and defective sperm binding to the zona pellucida. All of these knockout strains are reported to lack or show aberrant expression of a disintegrin and metallopeptidase domain 3 (ADAM3) on the sperm membrane. We performed proteomic analyses of the proteins of these infertile spermatozoa to clarify whether the abnormal function is caused exclusively by a deficiency in ADAM3 expression. Two proteins, named PMIS1 and PMIS2, were missing in spermatozoa from Clgn-disrupted mice. To study their roles, we generated two gene-disrupted mouse lines. Pmis1-knockout mice were fertile, but Pmis2-knockout males were sterile because of a failure of sperm transport into the oviducts. Pmis2-deficient spermatozoa also failed to bind to the zona pellucida. However, they showed normal fertilizing ability when eggs surrounded with cumulus cells were used for in vitro fertilization. Further analysis revealed that these spermatozoa lacked the ADAM3 protein, but the amount of PMIS2 was also severely reduced in Adam3-deficient spermatozoa. These results suggest that PMIS2 might function both as the ultimate factor regulating sperm transport into the oviducts and in modulating sperm–zona binding.

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137. ELUCIDATION OF THE MOLECULAR MECHANISMS THAT UNDERPIN CAPACITATION-ASSOCIATED SPERM SURFACE REMODELLING

Reproduction Fertility and Development ◽

10.1071/srb09abs137 ◽

2009 ◽

Vol 21 (9) ◽

pp. 56

Author(s):

B. Nixon ◽

B. Skinner ◽

R. J. Aitken

Keyword(s):

Zona Pellucida ◽

Intracellular Trafficking ◽

Molecular Mechanisms ◽

Surface Expression ◽

The Novel ◽

Post Translational Modification ◽

Sperm Surface ◽

Concomitant Reduction ◽

Molecular Machinery ◽

Sperm Membrane

Recent research from our laboratory has provided evidence that sperm-egg interaction is mediated by a multimeric sperm receptor complex. Furthermore, we have demonstrated that this complex is assembled on the sperm surface during the final phase of their maturation, a process known as capacitation. The mechanisms underpinning this capacitation-associated surface remodelling remain poorly understood and are the subject of our current investigation. Specifically we have focused on whether this process is driven by vesicle mediated, intracellular trafficking of proteins. For this purpose we have examined the presence and physiological significance of a key part of the molecular machinery necessary for this form of trafficking, namely the enzyme dynamin. Our studies revealed that sperm are endowed with at least two isoforms of dynamin (1 and 2) both of which reside within the peri-acrosomal region of the sperm head, a location compatible with a role in sperm membrane remodelling. Consistent with this putative role, it was demonstrated that dynamin 1 was phosphorylated during capacitation, a post-translational modification that has been causally linked to both its activation and to the capacitation-associated surface remodelling of mouse spermatozoa. Furthermore, it was demonstrated that pharmacological inhibition of dynamin activity led to a concomitant reduction in the ability of spermatozoa to bind to the zona pellucida of homologous oocytes. This suppression was also correlated with reduced surface expression of a number of proteins including a subset of putative sperm-zona pellucida receptors. Collectively these data support the novel hypothesis that dynamin does participate indirectly in sperm membrane remodelling events by virtue of its ability to mediate intracellular trafficking.

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