Abstract
Maturation promoting factor (MPF) is universally recognized as the biological entity responsible for driving the cell cycle from G2- to M-phase. Histone H1 kinase activity is widely accepted as a biochemical indicator of p34cdc2 protein kinase complex activity and therefore MPF activity. In this paper we present results which indicate that during the G2- to M-phase transition in mouse oocytes the dynamic of p34cdc2 related histone H1 kinase activity differs markedly from the biological activity of MPF as measured by classical cell fusion procedures. MPF is activated just before germinal vesicle breakdown (GVBD) whereas histone H1 kinase is activated 5-7 h later coincident with the formation of the definitive first metaphase plate. The biological activity of MPF is merely reduced to about 50% of control levels by a short period of protein synthesis inhibition (1-2 h) and completely suppressed after a prolonged period of inhibition (4-5 h). By contrast, inhibition of protein synthesis in mouse oocytes results in a rapid and complete suppression of histone H1 kinase activity. Therefore, biological MPF and histone H1 kinase activity should not be used in an interchangeable manner during the G2- to M-phase transition in mouse oocytes.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callMore From: The International Journal of Developmental Biology
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
