A profile of fertilization in mammals

Fertilization is defined as the process of union of two gametes, eggs and s perm. When mammalian eggs and sperm come into contact in the female oviduct , a series of steps is set in motion that can lead to fertilization and ult imately to development of new individuals. The pathway begins with species- specific binding of sperm to eggs and ends a relatively short time later wi th fusion of a single sperm with each egg. Although this process has been i nvestigated extensively, only recently have the molecular components of egg and sperm that participate in the mammalian fertilization pathway been ide ntified, Some of these components may participate in gamete adhesion and ex ocytosis, whereas others may be involved in gamete fusion, Here we describe selected aspects of mammalian fertilization and address some of the latest experimental evidence that bears on this important area of research.