Sperm plasma membrane

About: Sperm plasma membrane is a research topic. Over the lifetime, 1016 publications have been published within this topic receiving 49964 citations.

Adhesion molecules and matrix proteins on human spermatozoa.

Abstract: Ejaculated spermatozoa and spermatogenic cells express alpha- and beta-chains of beta 1, 3 and 4 integrins as well as their ligands fibronectin and laminin in an extended intra- and interindividual variation and in different patterns of location. The mRNA transcripts of these molecules were detectable by nested polymerase chain reaction in the spermatozoa. The conclusion of a functional competence of these adhesion molecules (AM) was supported by their relation to the results of the zona-free hamster oocyte penetration (HOP) test, the in vitro fertilization of human oocytes and cell attachment assays. AM labelling was influenced by the disintegration of the sperm plasma membrane, especially in seminal plasma, by progesterone, human follicular fluid and microorganisms, but was barely modified by sperm cryopreservation. Despite substantial advances in the knowledge about sperm adhesion molecules, many questions remain to be answered.

The Interactions of Sea Urchin Gametes During Fertilization

Abstract: The interactions between sea urchin spermatozoa and ova during fertilization usually exhibit a high degree of species specificity. Under natural conditions and reasonable gamete concentrations, most interspecific inseminations fail to yield zygotes. Macromolecules on the external surfaces of the apposing gametes must surely be responsible for successful gamete recognition, adhesion and fusion. Species specific recognition between surface components of sperm and egg could occur during at least three events comprising the fertilization process. The first event is the interaction of the sperm plasma membrane with the egg jelly coat. This induces the sperm acrosome reaction resulting in the exocytosis of the “bindin” -containing acrosome granule and also the extrusion of the acrosome process from the anterior tip of the sperm. The second event is the adhesion of the bindin-coated acrosome process to glycoprotein “bindin receptors” on the external surface of the egg vitelline layer. The third event is the penetration of the vitelline layer and the fusion of sperm and egg plasma membranes. With the isolations of the component of egg jelly which induces the acrosome reaction, sperm bindin from the acrosome vesicle and the egg surface bindin receptor from the vitelline layer, there is hope of discovering the molecular basis of this most interesting intercellular interaction which results in the activation of embryonic development.

Cross-linking a maturation-dependent ram sperm plasma membrane antigen induces the acrosome reaction.

Abstract: ESA152 is a highly hydrophobic 18 kDa sialoglycoprotein, which becomes expressed on ram sperm in the proximal cauda epididymis. ESA 152 is expressed on all regions of the sperm surface, most strongly on the posterior region of the head, most weakly on the anterior region of the head. In this paper, we show that induction of the acrosome reaction with Ca2+ ionophore causes ESA152 to be redistributed from the posterior to the anterior region of the head plasma membrane. Cross-linking ESA152 with bivalent antibody causes similar redistribution and induces the acrosome reaction, Induction of the acrosome reaction with ESA152 antibody requires Ca2+ but is insensitive to (10 ng/ml) pertussis toxin.