title: Triggering the all-or-nothing switch into mitosis.
abstract: The past decade of cell cycle investigations has identified many roads not taken. The kinase that drives mitosis can be modulated by cyclins, by activating phosphorylation, by inhibitory phosphorylation and by binding of inhibitors, but one of these regulatory options controls the transition from G2 phase to mitosis in most circumstances. A switch-like mechanism integrates signals of cellular status and commits the cell to mitosis by abruptly removing inhibitory phosphate from preformed cyclin:Cdk1 complexes. The pathways that flip this switch alter the balance of modifying reactions to favor dephosphorylation, thereby generating a flood of mitotic kinase.
authors.affiliation: Dept of Biochemistry and Biophysics, University of California, San Francisco, San Francisco, CA 94143-0448, USA. ofarrell@cgl.ucsf.edu
authors.forename: P H
authors.initials: PH
authors.lastname: O'Farrell
mesh_terms: D000818:Animals; D016203:CDC2 Protein Kinase / Q000378:metabolism*; D018844:Cyclin-Dependent Kinases / Q000378:metabolism*; D016213:Cyclins / Q000378:metabolism*; D016195:G2 Phase / Q000502:physiology*; D006801:Humans; D008938:Mitosis / Q000502:physiology*; D010766:Phosphorylation
chemical_list: D016213:Cyclins; D016203:CDC2 Protein Kinase; D018844:Cyclin-Dependent Kinases