Fertilization begins with species-restricted interaction of sperm and the egg-coating envelope, which includes a three-dimensional meshwork of filaments composed of glycoproteins (called ZP proteins). Growing evidence has unveiled the molecular nature of ZP proteins; however, the structural property conferring fertilization competence to the egg-coating envelope remains unknown. Here, we show t...

A pre-requisite for sexual reproduction is successful unification of the male and female gametes; in externally-fertilising echinoderms the male gamete is brought into close proximity to the female gamete through chemotaxis, the associated signalling and flagellar beat changes being elegantly characterised in several species. In the human, sperm traverse a relatively high-viscosity mucus coatin...

Experiment was conducted to evaluate the effect of different levels of egg yolk for coating and storing spermatozoa. Ejaculates were collected from four rams. In each session, second ejaculates (n=4) were collected in a tube containing 1 mL coating buffers which were prepared by 10, 15 or 20% egg yolk plus Tris-fructose. Samples were pooled, centrifuged and the supernatant removed in the labora...

Two experiments were designed to examine the effects of crude seminal plasma (CSP) exposure ofejaculated and epididymal spermatozoa before freezing. Experiment 1, two consecutive ejaculates werecollected (n=4) within 5 min, the second one was carried out in a tube containing Fiser extender (coatedspermatozoa); by centrifugation, seminal plasma was removed from coated ejaculates. The pellets wer...

sperms are highly specialized cells for delivering dna from male to the ovum. incredibly, wide degree of diversity in sperm morphology in their basic structures i.e. head, middle piece and tail is found across species. differences in terms of overall size of the sperm, shape and number of sperm produced are also incredible. one of the key for this variations or diversity in sperm may be associa...

We used fracture-label and surface labeling techniques to characterize the distribution and topology of wheat germ agglutinin (WGA) receptors in the plasma membrane of boar sperm heads. We show that freeze-fracture results in preferential, but not exclusive, partition of WGA-binding sites with the outer (exoplasmic) half of the plasma membrane. Labeling of the inner (protoplasmic) half of the m...

Understanding the biochemical processes associated with ovum fertilization and knowledge about the structure and function of individual substances participating in these processes is crucial for the development of biotechnological methods to improve reproduction of animals and humans. Among many components of seminal plasma, proteins and peptides play a specific role in regulation of the fertil...