Circadian rhythmicity by autocatalysis.
The temperature compensated in vitro oscillation of cyanobacterial KaiC phosphorylation, the first example of a thermodynamically closed system showing circadian rhythmicity, only involves the three Kai proteins (KaiA, KaiB, and KaiC) and ATP. In this paper, we describe a model in which the KaiA- and KaiB-assisted autocatalytic phosphorylation and dephosphorylation of KaiC are the source for circadian rhythmicity. This model, based upon autocatalysis instead of transcription-translation negative feedback, shows temperature-compensated circadian limit-cycle oscillations with KaiC phosphorylation profiles and has period lengths and rate constant values that are consistent with experimental observations.
Mehra
Arun
A
Department of Genetics, Dartmouth Medical School, Hanover, New Hampshire, USA.
Hong
Christian I
CI
Shi
Mi
M
Loros
Jennifer J
JJ
Dunlap
Jay C
JC
Ruoff
Peter
P
D001426:Bacterial Proteins / Q000378:metabolism*; D001683:Biological Clocks / Q000502:physiology*; D002384:Catalysis; D002940:Circadian Rhythm / Q000502:physiology*; D056925:Circadian Rhythm Signaling Peptides and Proteins; D003198:Computer Simulation; D000458:Cyanobacteria / Q000502:physiology*; D005246:Feedback / Q000502:physiology; D007700:Kinetics; D008954:Models, Biological; D010507:Periodicity; D010766:Phosphorylation; D015398:Signal Transduction; D013696:Temperature
D001426:Bacterial Proteins; D056925:Circadian Rhythm Signaling Peptides and Proteins; C114269:KaiA protein, cyanobacteria; C114270:KaiB protein, cyanobacteria; C114271:KaiC protein, cyanobacteria