Pathway: Interaction With Cumulus Cells And The Zona Pellucida
Reactions in pathway: Interaction With Cumulus Cells And The Zona Pellucida :
Interaction With Cumulus Cells And The Zona Pellucida
A typical mammalian egg is surrounded by an outer layer of about 3,000 cumulus cells embedded in an extracellular matrix rich in hyaluronic acid. It is suggested that the fertilizing sperm with it's acrosome intact, passes through the cumulus cell layer.
The zona pellucida (ZP), a glycoproteinaceous matrix surrounding the mammalian oocyte plays an important role in species specific sperm-egg binding, induction of acrosome reaction in the ZP bound spermatozoa, avoidance of polyspermy and protection of the embryo prior to implantation. The human ZP matrix is composed of 4 glycoproteins designated as ZP1, ZP2, ZP3 and ZP4.
Mammalian fertilization comprises sperm migration through the female reproductive tract, biochemical and morphological changes to sperm, and sperm-egg interaction in the oviduct. Although the broad concepts of fertilization are well defined, our understanding of the biochemical mechanisms underlying sperm-egg binding is limited.
Human reproduction mixes the genomes of two individuals, creating a new organism. The offspring individuals produced by sexual reproduction differ from their parents and from their siblings. Reproduction includes the reproductive system, sperm and egg production (haploid cells), fertilization, and the early stages embryo development.