Reconstitution of Circadian Oscillation of Cyanobacterial KaiC Phosphorylation in Vitro

@article{Nakajima2005ReconstitutionOC,
  title={Reconstitution of Circadian Oscillation of Cyanobacterial KaiC Phosphorylation in Vitro},
  author={Masato Nakajima and Keiko Imai and Hiroshi Ito and Taeko Nishiwaki and Yoriko Murayama and Hideo Iwasaki and Tokitaka Oyama and Takao Kondo},
  journal={Science},
  year={2005},
  volume={308},
  pages={414 - 415}
}
Kai proteins globally regulate circadian gene expression of cyanobacteria. The KaiC phosphorylation cycle, which persists even without transcription or translation, is assumed to be a basic timing process of the circadian clock. We have reconstituted the self-sustainable oscillation of KaiC phosphorylation in vitro by incubating KaiC with KaiA, KaiB, and adenosine triphosphate. The period of the in vitro oscillation was stable despite temperature change (temperature compensation), and the… 

Autonomous synchronization of the circadian KaiC phosphorylation rhythm

The cyanobacterial circadian oscillator can be reconstituted in vitro by mixing three purified clock proteins, KaiA, KaiB and KaiC, with ATP and it is demonstrated that synchronization is tightly linked with KaiC dephosphorylation and is mediated by monomer exchange between KaiC hexamers during the early deph phosphorylation phase.

Evolution Analysis of the Circadian Clock Protein KaiB

Here, the evolution of the KaiB protein is studied to help understand the development of the circadian clock system in cyanobacteria.

A Molecular Dynamics Study of the Cyanobacterial Clock Protein KaiA

The dynamics of the KaiA protein of Thermosynechococcus elongatus is studied in order to understand the function of KaiA and its binding with KaiC and to study the circadian system in cyanobacteria.

Expression and Purification of Cyanobacterial Circadian Clock Protein KaiC and Determination of Its Auto-phosphatase Activity.

Circadian clocks of cyanobacteria are the simplest and one of the best studied models and can be used for in vitro reconstitution experiments and determination of the auto-phosphatase activity of KaiC as described in this protocol.

A model for circadian rhythm of cyanobacteria , which maintains oscillation without gene expression

Results of the present paper suggest that KaiA and KaiB strengthen the nonlinearity of KaiC phosphorylation, thereby promote the circadian rhythm in cyanobacteria.

A cyanobacterial circadian clock based on the Kai oscillator.

  • T. Kondo
  • Biology
    Cold Spring Harbor symposia on quantitative biology
  • 2007
It is demonstrated that the oscillation of KaiC phosphorylation is the primary pacemaker of the cyanobacterial circadian clock and a novel function of proteins as timing devices that govern cellular metabolism is revealed.
...

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