Recent cyanobacterial Kai protein structures suggest a rotary clock.
The cyanobacterial circadian oscillator consists of three Kai proteins, KaiA, KaiB, and KaiC, in its oscillation feedback loop. Structural comparison reveals that the Kai system resembles the F1-ATPase system in which KaiC is equivalent to alpha(3)beta(3), KaiA to gammadelta, and KaiB to its inhibitory factor. It also suggests that there exists a possible haemagglutinin-like spring-loaded mechanism for the activation of KaiA during the formation of Kai complexes.
Wang
Jimin
J
Department of Molecular Biophysics and Biochemistry, Center for Structural Biology, Yale University, New Haven, Connecticut 06520-8114, USA. wang@mail.csb.yale.edu
D001426:Bacterial Proteins / Q000737:chemistry* / Q000378:metabolism; D001683:Biological Clocks; D056925:Circadian Rhythm Signaling Peptides and Proteins; D019281:Dimerization; D011487:Protein Conformation
D001426:Bacterial Proteins; D056925:Circadian Rhythm Signaling Peptides and Proteins; C114269:KaiA protein, cyanobacteria; C114270:KaiB protein, cyanobacteria; C114271:KaiC protein, cyanobacteria