Water Permeability,Lp, of the Mouse Sperm Plasma Membrane and Its Activation Energy Are Strongly Dependent on Interaction of the Plasma Membrane with the Sperm Cytoskeleton

Cryobiology ◽  
1997 ◽  
Vol 35 (1) ◽  
pp. 79-92 ◽  
Author(s):  
Esther E. Noiles ◽  
Kathleen A. Thompson ◽  
Bayard T. Storey
Keyword(s):  
Activation Energy ◽  
Plasma Membrane ◽  
Water Permeability ◽  
Mouse Sperm ◽  
Sperm Plasma Membrane

Interactions between gametes leading to fertilization: the sperm's eye view

1995 ◽  
Vol 7 (4) ◽  
pp. 927 ◽  
Author(s):  
BT Storey
Keyword(s):  
Plasma Membrane ◽  
Acrosome Reaction ◽  
Mammalian Species ◽  
Sperm Chromatin ◽  
Peptide Backbone ◽  
Mouse Sperm ◽  
Gamete Interactions ◽  
Sperm Plasma Membrane ◽  
Sperm Penetration ◽  
Strong Candidate

Sexual reproduction requires that the gamete carrying the male-derived haploid chromatin join with the gamete carrying the female-derived haploid chromatin during fertilization to produce the diploid zygote. To accomplish this feat, the sperm must not only meet the egg, it must recognize the egg and be recognized in turn by the egg, and in the end must enter and be engulfed by the egg. In this selective overview of gamete interactions that lead to fertilization, encounters of three kinds, followed by the finale of gamete fusion, are considered from the sperm's viewpoint, with particular emphasis on the mammalian species with the mouse as the principal model. The first encounter is with the zona pellucida of the egg, to whose surface the sperm must bind. Mouse sperm appear to have four binding sites for zona ligands. Three interact with sugar moieties of the oligosaccharide chains of the mouse zona glycoprotein ZP3; the fourth binds a peptide backbone arginine. Capacitation is not required for this encounter, but is obligate for the second encounter--induction of the acrosome reaction in the bound sperm. The acrosome reaction is an exocytotic process that makes available the enzymatic machinery needed for sperm penetration the zona which is the end point of a sequence of reactions directed by intracellular signalling systems. In mouse sperm, these systems are presumed to be activated by ligands on ZP3 binding to ligand-specific sperm receptors with consequent aggregation of receptors. No receptor has been identified with certainty, nor have candidates for putative ZP3 ligands been identified. Completion of the acrosome reaction allows the sperm to penetrate the zona and, bind to the egg plasma membrane, thereby completing the third encounter. In the mouse, a 94-kDa protein appears essential for this binding. In the guinea-pig, a sperm plasma membrane protein (formerly PH-30, now fertilin), is a strong candidate for the mediator of the fusion process by which the egg engulfs the sperm. Decondensation of the sperm chromatin reverses the remarkable packing of DNA organized by sperm protamines. Mitochondrial DNA is also engulfed by the egg; the question of whether this DNA makes a small finite, or null, contribution to cytosolic inheritance is still in debate. The puzzles attending these encounters are presented as reminders of the intricacy and fascination, as well as of the vital necessity, of gamete interaction.

scholarly journals A mouse sperm decapacitation factor receptor is phosphatidylethanolamine-binding protein 1

Reproduction ◽  
2005 ◽  
Vol 130 (4) ◽  
pp. 497-508 ◽  
Author(s):  
Rachel Gibbons ◽  
Susan A Adeoya-Osiguwa ◽  
Lynn R Fraser
Keyword(s):  
Plasma Membrane ◽  
Binding Protein ◽  
Human Sperm ◽  
Surface Proteins ◽  
Mouse Sperm ◽  
Fertility Treatments ◽  
State Dependent ◽  
Sperm Plasma Membrane ◽  
Associated Proteins ◽  
Functional Consequences

Capacitation is a pivotal event for mammalian spermatozoa, involving the loss of surface proteins known as decapacitation factors (DF) and consequent acquisition of fertilizing ability. Earlier studies showed that a mouse sperm DF binds to a receptor, DF-R, whose attachment to the sperm plasma membrane appears to involve a glycosylphosphatidylinositol (GPI) anchor. In the present study, purification and subsequent sequencing of DF-R has identified this ~23 kDa protein as phosphatidyletha-nolamine-binding protein 1 (PEBP 1). To obtain functional evidence that supports sequence homology data, purified recombinant PEBP 1 and PEBP 2 were evaluated for biological activity. While PEBP 1 was able to remove DF activity in solution at concentrations above ~1 nmol/l, PEBP 2 was ineffective, even at 600 nmol/l; this confirmed that DF-R is PEBP 1. Anti-PEBP 1 antiserum recognized recombinant PEBP 1 and a ~23 kDa protein in both mouse and human sperm lysates. Immunolocalization studies revealed that DF-R/PEBP 1 is located on the acrosomal cap, the post-acrosomal region and the flagellum of both mouse and human spermatozoa, with epitope accessibility being capacitation state-dependent and reversible. Treatment of cells with a phospholipase able to cleave GPI anchors essentially abolished immunostaining, thus confirming the extracellular location of DF-R/PEBP 1. We suggest that DF-R/PEBP 1 plays its fundamental role in capacitation by causing alterations in the sperm plasma membrane in both head and flagellum, with functional consequences for membrane-associated proteins. Obtaining more detail about DF ↔ DF-R interactions could lead to useful applications in both fertility treatments and new contraceptive approaches.

Lipid changes of goat sperm plasma membrane during epididymal maturation

1991 ◽  
Vol 1061 (2) ◽  
pp. 185-196 ◽  
Author(s):  
Ajay P.S. Rana ◽  
Gopal C. Majumder ◽  
Suniti Misra ◽  
Amitabha Ghosh
Keyword(s):  
Plasma Membrane ◽  
Epididymal Maturation ◽  
Sperm Plasma Membrane

Mechanism of human sperm activation by extracellular ATP

1996 ◽  
Vol 270 (6) ◽  
pp. C1709-C1714 ◽  
Author(s):  
C. Foresta ◽  
M. Rossato ◽  
P. Chiozzi ◽  
F. Di Virgilio
Keyword(s):  
Plasma Membrane ◽  
Acrosome Reaction ◽  
Human Sperm ◽  
Extracellular Atp ◽  
Effective Concentration ◽  
Na Channel ◽  
Monovalent Cations ◽  
Sperm Activation ◽  
Gated Channel ◽  
Sperm Plasma Membrane

We have identified the mechanism whereby extracellular ATP (ATPe) triggers the acrosome reaction in human spermatozoa. This nucleotide opens a ligand-gated ion channel expressed on the sperm plasma membrane. ATPe threshold and 50% effective concentration calculated on the total added ATPe are 0.1 and 2 mM, respectively, corresponding to a free ATP concentration (ATP4-) of 3 and 200 microM, respectively. The ATPe-gated channel is selective for monovalent cations (Na+, choline, and methylglucamine), whereas on the contrary, permeability to Ca2+ is negligible. Isosmolar replacement of extracellular Na+ with sucrose fully blocked ATPe-dependent sperm activation, thus suggesting a mandatory role for Na+ influx. These results show that human sperm express an ATPe-gated Na+ channel that might have an important role in sperm activation before egg fertilization.

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