In vitro regulation of circadian phosphorylation rhythm of cyanobacterial clock protein KaiC by KaiA and KaiB

FEBS Lett. 2010 Mar 5;584(5):898-902. doi: 10.1016/j.febslet.2010.01.016. Epub 2010 Jan 16.

Abstract

Biochemical circadian oscillation of KaiC phosphorylation, by mixing three Kai proteins and ATP, has been proven to be the central oscillator of the cyanobacterial circadian clock. In vivo, the intracellular levels of KaiB and KaiC oscillate in a circadian fashion. By scrutinizing KaiC phosphorylation rhythm in a wide range of Kai protein concentrations, KaiA and KaiB were found to be "parameter-tuning" and "state-switching" regulators of KaiC phosphorylation rhythm, respectively. Our results also suggest a possible entrainment mechanism of the cellular circadian clock with the circadian variation of intracellular levels of Kai proteins.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Bacterial Proteins / genetics
  • Bacterial Proteins / metabolism*
  • Circadian Rhythm / genetics
  • Circadian Rhythm / physiology*
  • Circadian Rhythm Signaling Peptides and Proteins / genetics
  • Circadian Rhythm Signaling Peptides and Proteins / metabolism*
  • Cyanobacteria / metabolism
  • Cyanobacteria / physiology*
  • Phosphorylation
  • Recombinant Proteins / genetics
  • Recombinant Proteins / metabolism

Substances

  • Bacterial Proteins
  • Circadian Rhythm Signaling Peptides and Proteins
  • KaiA protein, cyanobacteria
  • KaiB protein, cyanobacteria
  • KaiC protein, cyanobacteria
  • Recombinant Proteins