PT - JOURNAL ARTICLE AU - Ray, L. Bryan TI - Cell Cycle Fertilization Trigger AID - 10.1126/scisignal.4170ec121 DP - 2011 Apr 26 TA - Science Signaling PG - ec121--ec121 VI - 4 IP - 170 4099 - http://stke.sciencemag.org/content/4/170/ec121.short 4100 - http://stke.sciencemag.org/content/4/170/ec121.full SO - Sci. Signal.2011 Apr 26; 4 AB - A critical point of cell cycle control, with implications for reproduction, is the exit of oocytes from meiosis II, the stage at which oocytes arrest until they are fertilized. One mechanism that contributes to this process is proteolytic degradation of cyclin B and consequent inactivation of the cyclin-dependent kinase Cdc2. Another mechanism for inhibiting activity of Cdc2 is phosphorylation by the protein kinase Wee1B. Oh et al. present evidence that this mechanism is also critical in mouse oocytes. Fertilization causes an increase in the intracellular concentration of free Ca2+, thus activating calcium-calmodulin–dependent protein kinase II, which in turn activates Wee1B. J. S. Oh, A. Susor, M. Conti, Protein tyrosine kinase Wee1B is essential for metaphase II exit in mouse oocytes. Science 332, 462–465 (2011). [Abstract] [Full Text]