Signalling in mammalian egg activation: role of protein kinases

Embryonic development is initiated after the fertiliziing spermatozoon enters the egg and triggers a process known as 'egg activation'. Activation results in in increase in intracellular calcium concentration, cortical granule exocytosis (CGE), cell cycle resumption and recruitment of maternal mRNA. Various treatments can induce parthenogenetic activation characterized by the same manifestations. Signal transducton pathways similar to those known for somatic cells mediate the mammalian egg activation. This review focuses on the signal transduction pathways that occur during mammalian fertilization and during parthenogenetic egg activation. We discuss the possibility that members of the protein tyrosine kinase (PTKs) families. the Src Family PTKs in particular, operate during egg activation and that protein kinase C can induce CGE. (C) 2002 Elsevier Science Ireland Ltd. All rights reserved.