Click here to close
Hello! We notice that you are using Internet Explorer, which is not supported by Xenbase and may cause the site to display incorrectly.
We suggest using a current version of Chrome,
FireFox, or Safari.
???displayArticle.abstract???
In Xenopus embryos, the cell cycle is driven by an autonomous biochemical oscillator that controls the periodic activation and inactivation of cyclin B1-CDK1. The oscillator circuit includes a system of three interlinked positive and double-negative feedback loops (CDK1 -> Cdc25 -> CDK1; CDK1 -/ Wee1 -/ CDK1; and CDK1 -/ Myt1 -/ CDK1) that collectively function as a bistable trigger. Previous work established that this bistable trigger is essential for CDK1 oscillations in the early embryonic cell cycle. Here, we assess the importance of the trigger in the somatic cell cycle, where checkpoints and additional regulatory mechanisms could render it dispensable. Our approach was to express the phosphorylation site mutant CDK1AF, which short-circuits the feedback loops, in HeLa cells, and to monitor cell cycle progression by live cell fluorescence microscopy. We found that CDK1AF-expressing cells carry out a relatively normal first mitosis, but then undergo rapid cycles of cyclin B1 accumulation and destruction at intervals of 3-6 h. During these cycles, the cells enter and exit M phase-like states without carrying out cytokinesis or karyokinesis. Phenotypically similar rapid cycles were seen in Wee1 knockdown cells. These findings show that the interplay between CDK1, Wee1/Myt1, and Cdc25 is required for the establishment of G1 phase, for the normal approximately 20-h cell cycle period, and for the switch-like oscillations in cyclin B1 abundance characteristic of the somatic cell cycle. We propose that the HeLa cell cycle is built upon an unreliable negative feedback oscillator and that the normal high reliability, slow pace and switch-like character of the cycle is imposed by a bistable CDK1/Wee1/Myt1/Cdc25 system.
Beal,
Effect of UV on cleavage of Xenopus laevis.
1975, Pubmed,
Xenbase
Beal,
Effect of UV on cleavage of Xenopus laevis.
1975,
Pubmed
,
Xenbase
Berridge,
The versatility and complexity of calcium signalling.
2001,
Pubmed
Blasina,
The role of inhibitory phosphorylation of CDC2 following DNA replication block and radiation-induced damage in human cells.
1997,
Pubmed
Chan,
Kinetochore structure and function.
2005,
Pubmed
Chen,
Integrative analysis of cell cycle control in budding yeast.
2004,
Pubmed
Ciliberto,
Steady states and oscillations in the p53/Mdm2 network.
2005,
Pubmed
Cohen-Fix,
Anaphase initiation in Saccharomyces cerevisiae is controlled by the APC-dependent degradation of the anaphase inhibitor Pds1p.
1996,
Pubmed
,
Xenbase
Cross,
Two redundant oscillatory mechanisms in the yeast cell cycle.
2003,
Pubmed
Cross,
Testing a mathematical model of the yeast cell cycle.
2002,
Pubmed
Elowitz,
A synthetic oscillatory network of transcriptional regulators.
2000,
Pubmed
Gerhart,
Cell cycle dynamics of an M-phase-specific cytoplasmic factor in Xenopus laevis oocytes and eggs.
1984,
Pubmed
,
Xenbase
Gong,
Cyclin A2 regulates nuclear-envelope breakdown and the nuclear accumulation of cyclin B1.
2007,
Pubmed
Goodwin,
Oscillatory behavior in enzymatic control processes.
1965,
Pubmed
Gould,
Tyrosine phosphorylation of the fission yeast cdc2+ protein kinase regulates entry into mitosis.
1989,
Pubmed
Gupta,
Rescue of a human cell line from endogenous Cdk1 depletion by Cdk1 lacking inhibitory phosphorylation sites.
2007,
Pubmed
Hagting,
Human securin proteolysis is controlled by the spindle checkpoint and reveals when the APC/C switches from activation by Cdc20 to Cdh1.
2002,
Pubmed
Harris,
The p53 pathway: positive and negative feedback loops.
2005,
Pubmed
Hershko,
Components of a system that ligates cyclin to ubiquitin and their regulation by the protein kinase cdc2.
1994,
Pubmed
HODGKIN,
A quantitative description of membrane current and its application to conduction and excitation in nerve.
1952,
Pubmed
Jackman,
Active cyclin B1-Cdk1 first appears on centrosomes in prophase.
2003,
Pubmed
Jaspersen,
Inhibitory phosphorylation of the APC regulator Hct1 is controlled by the kinase Cdc28 and the phosphatase Cdc14.
1999,
Pubmed
Jin,
Role of inhibitory CDC2 phosphorylation in radiation-induced G2 arrest in human cells.
1996,
Pubmed
Jin,
Nuclear localization of cyclin B1 controls mitotic entry after DNA damage.
1998,
Pubmed
Jones,
Probing the precision of the mitotic clock with a live-cell fluorescent biosensor.
2004,
Pubmed
Kanda,
Histone-GFP fusion protein enables sensitive analysis of chromosome dynamics in living mammalian cells.
1998,
Pubmed
King,
A 20S complex containing CDC27 and CDC16 catalyzes the mitosis-specific conjugation of ubiquitin to cyclin B.
1995,
Pubmed
,
Xenbase
King,
How proteolysis drives the cell cycle.
1996,
Pubmed
Krek,
Mutations of p34cdc2 phosphorylation sites induce premature mitotic events in HeLa cells: evidence for a double block to p34cdc2 kinase activation in vertebrates.
1991,
Pubmed
Leonhardt,
Dynamics of DNA replication factories in living cells.
2000,
Pubmed
Lewis,
Calcium signaling mechanisms in T lymphocytes.
2001,
Pubmed
Liou,
STIM is a Ca2+ sensor essential for Ca2+-store-depletion-triggered Ca2+ influx.
2005,
Pubmed
Listovsky,
Mammalian Cdh1/Fzr mediates its own degradation.
2004,
Pubmed
,
Xenbase
Lopez-Girona,
Serine-345 is required for Rad3-dependent phosphorylation and function of checkpoint kinase Chk1 in fission yeast.
2001,
Pubmed
Moir,
Nuclear lamins A and B1: different pathways of assembly during nuclear envelope formation in living cells.
2000,
Pubmed
Murray,
The role of cyclin synthesis and degradation in the control of maturation promoting factor activity.
1989,
Pubmed
,
Xenbase
Musacchio,
The spindle-assembly checkpoint in space and time.
2007,
Pubmed
Myers,
Silencing gene expression with Dicer-generated siRNA pools.
2005,
Pubmed
Nasmyth,
At the heart of the budding yeast cell cycle.
1996,
Pubmed
Nigg,
Mitotic kinases as regulators of cell division and its checkpoints.
2001,
Pubmed
Norbury,
Regulatory phosphorylation of the p34cdc2 protein kinase in vertebrates.
1991,
Pubmed
,
Xenbase
Novak,
Numerical analysis of a comprehensive model of M-phase control in Xenopus oocyte extracts and intact embryos.
1993,
Pubmed
,
Xenbase
Novak,
Mathematical model of the cell division cycle of fission yeast.
2001,
Pubmed
Pines,
Mitosis: a matter of getting rid of the right protein at the right time.
2006,
Pubmed
Pomerening,
Systems-level dissection of the cell-cycle oscillator: bypassing positive feedback produces damped oscillations.
2005,
Pubmed
,
Xenbase
Pomerening,
Building a cell cycle oscillator: hysteresis and bistability in the activation of Cdc2.
2003,
Pubmed
,
Xenbase
Ptacek,
Global analysis of protein phosphorylation in yeast.
2005,
Pubmed
Rape,
Autonomous regulation of the anaphase-promoting complex couples mitosis to S-phase entry.
2004,
Pubmed
Reppert,
Coordination of circadian timing in mammals.
2002,
Pubmed
Rust,
Ordered phosphorylation governs oscillation of a three-protein circadian clock.
2007,
Pubmed
Sarkaria,
Inhibition of ATM and ATR kinase activities by the radiosensitizing agent, caffeine.
1999,
Pubmed
Sha,
Hysteresis drives cell-cycle transitions in Xenopus laevis egg extracts.
2003,
Pubmed
,
Xenbase
Sudakin,
The cyclosome, a large complex containing cyclin-selective ubiquitin ligase activity, targets cyclins for destruction at the end of mitosis.
1995,
Pubmed
Thron,
A model for a bistable biochemical trigger of mitosis.
1996,
Pubmed
Toyoshima-Morimoto,
Polo-like kinase 1 phosphorylates cyclin B1 and targets it to the nucleus during prophase.
2001,
Pubmed
,
Xenbase
Tyson,
Regulation of the eukaryotic cell cycle: molecular antagonism, hysteresis, and irreversible transitions.
2001,
Pubmed
Ubersax,
Targets of the cyclin-dependent kinase Cdk1.
2003,
Pubmed
Uhlmann,
Sister-chromatid separation at anaphase onset is promoted by cleavage of the cohesin subunit Scc1.
1999,
Pubmed
Visintin,
CDC20 and CDH1: a family of substrate-specific activators of APC-dependent proteolysis.
1997,
Pubmed
Waizenegger,
Two distinct pathways remove mammalian cohesin from chromosome arms in prophase and from centromeres in anaphase.
2000,
Pubmed
,
Xenbase
Walsh,
Phosphorylation of the cyclin b1 cytoplasmic retention sequence by mitogen-activated protein kinase and Plx.
2003,
Pubmed
,
Xenbase
Wasserman,
The cyclic behavior of a cytoplasmic factor controlling nuclear membrane breakdown.
1978,
Pubmed
,
Xenbase
Zhou,
Harnessing the ubiquitination machinery to target the degradation of specific cellular proteins.
2000,
Pubmed