ATPase activity and its temperature compensation of the cyanobacterial clock protein KaiC

KaiA, KaiB and KaiC constitute the circadian clock machinery in cyanobacteria. KaiC is a homohexamer; its subunit contains duplicated halves, each with a set of ATPase motifs. Here, using highly purified KaiC preparations of the thermophilic cyanobacterium Thermosynechococcus elongatus BP‐1 produced in Escherichia coli, we found that the N‐ and C‐terminal domains of KaiC had extremely weak ATPase activity. ATPase activity showed temperature compensation in wild‐type KaiC, but not in KaiCS431A/T432A, a mutant that lacks two phosphorylation sites. We concluded that KaiC phosphorylation is involved in the ATPase temperature‐compensation mechanism—which is probably critical to the stability of the circadian clock in cyanobacteria—and we hypothesized the following temperature‐compensation mechanism: (i) The C‐terminal phosphorylation sites of a KaiC hexamer subunit are phosphorylated by the C‐terminal domain of an adjacent KaiC subunit; (ii) the phosphorylation suppresses the ATPase activity of the C‐terminal domain; and (iii) the phosphorylated KaiC spontaneously dephosphorylates, resulting in the recover of ATPase activity.

[1]  Kenichi Hitomi,et al.  Tetrameric Architecture of the Circadian Clock Protein KaiB , 2005, Journal of Biological Chemistry.

[2]  Takao Kondo,et al.  KaiA-stimulated KaiC phosphorylation in circadian timing loops in cyanobacteria , 2002, Proceedings of the National Academy of Sciences of the United States of America.

[3]  T. Kondo,et al.  Nucleotide binding and autophosphorylation of the clock protein KaiC as a circadian timing process of cyanobacteria. , 2000, Proceedings of the National Academy of Sciences of the United States of America.

[4]  Takao Kondo,et al.  ATPase activity of KaiC determines the basic timing for circadian clock of cyanobacteria , 2007, Proceedings of the National Academy of Sciences.

[5]  Katsumi Imada,et al.  ATP‐induced hexameric ring structure of the cyanobacterial circadian clock protein KaiC , 2003, Genes to cells : devoted to molecular & cellular mechanisms.

[6]  Atsushi Hijikata,et al.  Role of KaiC phosphorylation in the circadian clock system of Synechococcus elongatus PCC 7942. , 2004, Proceedings of the National Academy of Sciences of the United States of America.

[7]  Fumio Hayashi,et al.  Hexamerization by the N-terminal domain and intersubunit phosphorylation by the C-terminal domain of cyanobacterial circadian clock protein KaiC. , 2006, Biochemical and biophysical research communications.

[8]  Shigeru Itoh,et al.  Roles of Two ATPase-Motif-containing Domains in Cyanobacterial Circadian Clock Protein KaiC* , 2004, Journal of Biological Chemistry.

[9]  M. Cox,et al.  recA protein-promoted ATP hydrolysis occurs throughout recA nucleoprotein filaments. , 1987, The Journal of biological chemistry.

[10]  Fumio Hayashi,et al.  Stoichiometric interactions between cyanobacterial clock proteins KaiA and KaiC. , 2004, Biochemical and biophysical research communications.

[11]  B. Sweeney,et al.  A CIRCADIAN RHYTHM IN CELL DIVISION IN A PROKARYOTE, THE CYANOBACTERIUM SYNECHOCOCCUS WH7803 1 , 1989 .

[12]  M. Ishiura,et al.  Circadian Rhythms in the Thermophilic Cyanobacterium Thermosynechococcus elongatus: Compensation of Period Length over a Wide Temperature Range , 2004, Journal of bacteriology.

[13]  L. Hightower,et al.  Unfolded proteins stimulate molecular chaperone Hsc70 ATPase by accelerating ADP/ATP exchange. , 1992, Biochemistry.

[14]  T. Kondo,et al.  The circadian clocks of plants and cyanobacteria. , 1999, Trends in plant science.

[15]  J. Dunlap.  Molecular Bases for Circadian Clocks , 1999, Cell.

[16]  K. Namba,et al.  Functionally Important Substructures of Circadian Clock Protein KaiB in a Unique Tetramer Complex* , 2005, Journal of Biological Chemistry.

[17]  Tetsuya Mori,et al.  Circadian clock protein KaiC forms ATP-dependent hexameric rings and binds DNA , 2002, Proceedings of the National Academy of Sciences of the United States of America.

[18]  Takao Kondo,et al.  KaiB functions as an attenuator of KaiC phosphorylation in the cyanobacterial circadian clock system , 2003, The EMBO journal.

[19]  Martin Egli,et al.  Visualizing a circadian clock protein: crystal structure of KaiC and functional insights. , 2004, Molecular cell.

[20]  Martin Egli,et al.  Analysis of KaiA–KaiC protein interactions in the cyano‐bacterial circadian clock using hybrid structural methods , 2006, The EMBO journal.

[21]  M. Cox.  The bacterial RecA protein as a motor protein. , 2003, Annual review of microbiology.

[22]  U. K. Laemmli,et al.  Cleavage of Structural Proteins during the Assembly of the Head of Bacteriophage T4 , 1970, Nature.

[23]  Martin Egli,et al.  Identification of key phosphorylation sites in the circadian clock protein KaiC by crystallographic and mutagenetic analyses. , 2004, Proceedings of the National Academy of Sciences of the United States of America.

[24]  Detlef D. Leipe,et al.  The bacterial replicative helicase DnaB evolved from a RecA duplication. , 2000, Genome research.

[25]  T. Nakatsu,et al.  Crystal structure of the C-terminal clock-oscillator domain of the cyanobacterial KaiA protein , 2004, Nature Structural &Molecular Biology.

[26]  T. Kondo,et al.  Cyanobacterial circadian pacemaker: Kai protein complex dynamics in the KaiC phosphorylation cycle in vitro. , 2006, Molecular cell.

[27]  T. Kondo,et al.  The circadian clock of cyanobacteria. , 2000, BioEssays : news and reviews in molecular, cellular and developmental biology.

[28]  T. Kondo,et al.  Reconstitution of Circadian Oscillation of Cyanobacterial KaiC Phosphorylation in Vitro , 2005, Science.

[29]  S. Golden,et al.  Structure and function from the circadian clock protein KaiA of Synechococcus elongatus: A potential clock input mechanism , 2002, Proceedings of the National Academy of Sciences of the United States of America.

[30]  M. Go,et al.  Two KaiA‐binding domains of cyanobacterial circadian clock protein KaiC , 2001, FEBS letters.

[31]  T. Yamaoka,et al.  Photosynthetic activities of a thermophilic blue-green alga , 1978 .

[32]  C. Johnson,et al.  Expression of a gene cluster kaiABC as a circadian feedback process in cyanobacteria. , 1998, Science.