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Q79PF4 (KAIC_SYNE7) Reviewed, UniProtKB/Swiss-Prot

Last modified June 11, 2014. Version 96. Feed History...

Clusters with 100%, 90%, 50% identity | Documents (2) | Third-party data text xml rdf/xml gff fasta
to top of pageNames·Attributes·General annotation·Ontologies·Interactions·Sequence annotation·Sequences·References·Cross-refs·Entry info·DocumentsCustomize order

Names and origin

Protein namesRecommended name:
Circadian clock protein kinase KaiC

EC=2.7.11.1
Gene names
Name:kaiC
Ordered Locus Names:Synpcc7942_1216
ORF Names:see0011
OrganismSynechococcus elongatus (strain PCC 7942) (Anacystis nidulans R2) [Complete proteome] [HAMAP]
Taxonomic identifier1140 [NCBI]
Taxonomic lineageBacteriaCyanobacteriaOscillatoriophycideaeChroococcalesSynechococcus

Protein attributes

Sequence length519 AA.
Sequence statusComplete.
Protein existenceEvidence at protein level

General annotation (Comments)

Function

Core component of the KaiABC clock protein complex, which constitutes the main circadian regulator in cyanobacteria. Binds to DNA. The KaiABC complex may act as a promoter-nonspecific transcription regulator that represses transcription, possibly by acting on the state of chromosome compaction. Ref.1 Ref.12

Catalytic activity

ATP + a protein = ADP + a phosphoprotein. HAMAP-Rule MF_01836

Cofactor

Magnesium. Ref.15

Enzyme regulation

The interaction with KaiA enhances its phosphorylation status, while the interaction with KaiB decreases it. A KaiA dimer is sufficient to enhance KaiC phosphorylation. Ref.8 Ref.10 Ref.11

Subunit structure

Homohexamer; hexamerization is dependent on ATP-binding. Core component of the KaiABC complex, at least composed of a KaiC homohexamer, a KaiB dimer and two KaiA dimers. Interacts directly with SasA. Ref.4 Ref.6 Ref.7 Ref.9 Ref.10 Ref.11

Developmental stage

Accumulates in a circadian fashion, peaking at circadian time (CT) 15-18. Ref.14

Induction

Down-regulated by itself. Ref.8 Ref.10 Ref.11 Ref.12

Domain

The KaiC domains mediate the interaction with KaiA. HAMAP-Rule MF_01836

Post-translational modification

Phosphorylated on serine/threonine residues by autocatalysis. Both phosphorylated and unphosphorylated forms exist. Can probably autophosphorylate and autodephosphorylate. Phosphorylated form correlates with clock speed. Ref.5 Ref.8 Ref.10 Ref.11

Miscellaneous

'Kai' means 'cycle' in Japanese.

Sequence similarities

Belongs to the KaiC family.

Contains 2 kaiC domains.

Ontologies

Keywords
   Biological processBiological rhythms
Transcription
Transcription regulation
   DomainRepeat
   LigandATP-binding
DNA-binding
Magnesium
Metal-binding
Nucleotide-binding
   Molecular functionKinase
Repressor
Serine/threonine-protein kinase
Transferase
   PTMPhosphoprotein
   Technical term3D-structure
Complete proteome
Gene Ontology (GO)
   Biological_processcircadian rhythm

Inferred from electronic annotation. Source: UniProtKB-HAMAP

entrainment of circadian clock

Inferred from direct assay Ref.4. Source: UniProtKB

negative regulation of circadian rhythm

Traceable author statement Ref.7. Source: UniProtKB

regulation of phosphorelay signal transduction system

Inferred from direct assay PubMed 16882723. Source: CACAO

regulation of transcription, DNA-templated

Inferred from electronic annotation. Source: UniProtKB-KW

transcription, DNA-templated

Inferred from electronic annotation. Source: UniProtKB-KW

   Molecular_functionATP binding

Inferred from electronic annotation. Source: UniProtKB-HAMAP

DNA binding

Inferred from electronic annotation. Source: UniProtKB-KW

identical protein binding

Inferred from physical interaction Ref.4. Source: IntAct

magnesium ion binding

Inferred from electronic annotation. Source: UniProtKB-HAMAP

protein binding

Inferred from physical interaction Ref.4Ref.6Ref.7PubMed 12441347Ref.11PubMed 19395479. Source: IntAct

protein serine/threonine kinase activity

Inferred from electronic annotation. Source: UniProtKB-KW

protein serine/threonine/tyrosine kinase activity

Inferred from electronic annotation. Source: UniProtKB-HAMAP

Complete GO annotation...

Binary interactions

Sequence annotation (Features)

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifier

Molecule processing

Chain1 – 519519Circadian clock protein kinase KaiC HAMAP-Rule MF_01836
PRO_0000217782

Regions

Domain19 – 260242KaiC 1
Domain261 – 493233KaiC 2
Nucleotide binding46 – 538ATP HAMAP-Rule MF_01836
Nucleotide binding288 – 2958ATP HAMAP-Rule MF_01836

Sites

Metal binding2951Magnesium
Metal binding3181Magnesium
Metal binding3191Magnesium
Metal binding3781Magnesium

Amino acid modifications

Modified residue4321Phosphothreonine; by autocatalysis HAMAP-Rule MF_01836

Experimental info

Mutagenesis521K → A: Induces an arrhythmic phenotype. Ref.5
Mutagenesis711G → A: Lowers the amplitude and distords the waveform of the circadian rhythm. Ref.5
Mutagenesis871A → V in kaiC1; shortens the period of the circadian rhythm to 22 hours.
Mutagenesis1141G → A: Extends the period of the circadian rhythm to 27 hours. Ref.5
Mutagenesis1151Q → A: Abolishes the circadian rhythm. Ref.5
Mutagenesis1571S → C in kaiC2; extends the period of the circadian rhythm to 29 hours.
Mutagenesis2151R → C in kaiC3; shortens the period of the circadian rhythm to 16 hours and decreases the interaction with KaiA.
Mutagenesis2361P → S in kaiC4; extends the period of the circadian rhythm to 28 hours.
Mutagenesis2481P → L in kaiC6; induces a low amplitude phenotype and decreases the interaction with KaiA.
Mutagenesis2481P → S in kaiC5; induces an arrhythmic phenotype.
Mutagenesis2531R → H in kaiC7; extends the period of the circadian rhythm to 40 hours.
Mutagenesis2731M → I in kaiC8; extends the period of the circadian rhythm to 37 hours.
Mutagenesis2941K → A: Induces a long period phenotype. Ref.5
Mutagenesis3211R → Q in kaiC9; shortens the period of the circadian rhythm to 21 hours.
Mutagenesis4091T → A in kaiC10; extends the period of the circadian rhythm to 27 hours.
Mutagenesis4211G → R in kaiC11; extends the period of the circadian rhythm to 44 hours and increases the interaction with KaiA.
Mutagenesis4221A → T in kaiC15; able to suppress the kaiA2 extended phenotype.
Mutagenesis4321T → A: Loss of function. Ref.15
Mutagenesis4421Y → H in kaiC12; extends the period of the circadian rhythm to 60 hours and increases the interaction with KaiA.
Mutagenesis4601G → E in kaiC13; induces an arrhythmic phenotype.
Mutagenesis4951T → A in kaiC14; induces an arrhythmic phenotype.

Secondary structure

........................................................................................................ 519
Helix Strand Turn

Details...

Sequences

Sequence LengthMass (Da)Tools
Q79PF4 [UniParc].

Last modified July 5, 2004. Version 1.
Checksum: 855DFE131EFFF3CF

FASTA51958,003
        10         20         30         40         50         60 
MTSAEMTSPN NNSEHQAIAK MRTMIEGFDD ISHGGLPIGR STLVSGTSGT GKTLFSIQFL 

        70         80         90        100        110        120 
YNGIIEFDEP GVFVTFEETP QDIIKNARSF GWDLAKLVDE GKLFILDASP DPEGQEVVGG 

       130        140        150        160        170        180 
FDLSALIERI NYAIQKYRAR RVSIDSVTSV FQQYDASSVV RRELFRLVAR LKQIGATTVM 

       190        200        210        220        230        240 
TTERIEEYGP IARYGVEEFV SDNVVILRNV LEGERRRRTL EILKLRGTSH MKGEYPFTIT 

       250        260        270        280        290        300 
DHGINIFPLG AMRLTQRSSN VRVSSGVVRL DEMCGGGFFK DSIILATGAT GTGKTLLVSR 

       310        320        330        340        350        360 
FVENACANKE RAILFAYEES RAQLLRNAYS WGMDFEEMER QNLLKIVCAY PESAGLEDHL 

       370        380        390        400        410        420 
QIIKSEINDF KPARIAIDSL SALARGVSNN AFRQFVIGVT GYAKQEEITG LFTNTSDQFM 

       430        440        450        460        470        480 
GAHSITDSHI STITDTIILL QYVEIRGEMS RAINVFKMRG SWHDKAIREF MISDKGPDIK 

       490        500        510 
DSFRNFERII SGSPTRITVD EKSELSRIVR GVQEKGPES 

« Hide

References

« Hide 'large scale' references
[1]"Expression of a gene cluster kaiABC as a circadian feedback process in cyanobacteria."
Ishiura M., Kutsuna S., Aoki S., Iwasaki H., Andersson C.R., Tanabe A., Golden S.S., Johnson C.H., Kondo T.
Science 281:1519-1523(1998) [PubMed] [Europe PMC] [Abstract]
Cited for: NUCLEOTIDE SEQUENCE [GENOMIC DNA], FUNCTION, MUTANTS KAIC1; KAIC2; KAIC3; KAIC4; KAIC5; KAIC6; KAIC7; KAIC8; KAIC9; KAIC10; KAIC11; KAIC12; KAIC13 AND KAIC14.
[2]"Synechococcus elongatus PCC7942 cosmid 7G3."
Holtman C.K., Sandoval P., Chen Y., Socias T., Mohler B.J., McMurtry S., Gonzalez A., Salinas I., Golden S.S., Youderian P.
Submitted (JUN-2002) to the EMBL/GenBank/DDBJ databases
Cited for: NUCLEOTIDE SEQUENCE [GENOMIC DNA].
[3]"Complete sequence of chromosome 1 of Synechococcus elongatus PCC 7942."
US DOE Joint Genome Institute
Copeland A., Lucas S., Lapidus A., Barry K., Detter J.C., Glavina T., Hammon N., Israni S., Pitluck S., Schmutz J., Larimer F., Land M., Kyrpides N., Lykidis A., Richardson P.
Submitted (AUG-2005) to the EMBL/GenBank/DDBJ databases
Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA].
Strain: PCC 7942.
[4]"Physical interactions among circadian clock proteins KaiA, KaiB and KaiC in cyanobacteria."
Iwasaki H., Taniguchi Y., Ishiura M., Kondo T.
EMBO J. 18:1137-1145(1999) [PubMed] [Europe PMC] [Abstract]
Cited for: INTERACTION WITH KAIA AND KAIB.
[5]"Nucleotide binding and autophosphorylation of the clock protein KaiC as a circadian timing process of cyanobacteria."
Nishiwaki T., Iwasaki H., Ishiura M., Kondo T.
Proc. Natl. Acad. Sci. U.S.A. 97:495-499(2000) [PubMed] [Europe PMC] [Abstract]
Cited for: ATP-BINDING, AUTOPHOSPHORYLATION, MUTAGENESIS OF LYS-52; GLY-71; GLY-114; GLN-115 AND LYS-294.
[6]"A kaiC-interacting sensory histidine kinase, SasA, necessary to sustain robust circadian oscillation in cyanobacteria."
Iwasaki H., Williams S.B., Kitayama Y., Ishiura M., Golden S.S., Kondo T.
Cell 101:223-233(2000) [PubMed] [Europe PMC] [Abstract]
Cited for: INTERACTION WITH SASA.
[7]"Two KaiA-binding domains of cyanobacterial circadian clock protein KaiC."
Taniguchi Y., Yamaguchi A., Hijikata A., Iwasaki H., Kamagata K., Ishiura M., Go M., Kondo T.
FEBS Lett. 496:86-90(2001) [PubMed] [Europe PMC] [Abstract]
Cited for: INTERACTION WITH KAIA, MUTANTS KAIC3; KAIC6; KAIC11 AND KAIC12.
[8]"KaiA-stimulated KaiC phosphorylation in circadian timing loops in cyanobacteria."
Iwasaki H., Nishiwaki T., Kitayama Y., Nakajima M., Kondo T.
Proc. Natl. Acad. Sci. U.S.A. 99:15788-15793(2002) [PubMed] [Europe PMC] [Abstract]
Cited for: PHOSPHORYLATION, ENZYME REGULATION, MUTANT KAIC15.
[9]"Circadian clock protein KaiC forms ATP-dependent hexameric rings and binds DNA."
Mori T., Saveliev S.V., Xu Y., Stafford W.F., Cox M.M., Inman R.B., Johnson C.H.
Proc. Natl. Acad. Sci. U.S.A. 99:17203-17208(2002) [PubMed] [Europe PMC] [Abstract]
Cited for: HEXAMERIZATION, DNA-BINDING, ATP-BINDING.
[10]"Cyanobacterial circadian clockwork: roles of KaiA, KaiB and the kaiBC promoter in regulating KaiC."
Xu Y., Mori T., Johnson C.H.
EMBO J. 22:2117-2126(2003) [PubMed] [Europe PMC] [Abstract]
Cited for: ENZYME REGULATION, PHOSPHORYLATION, INTERACTION WITH KAIB.
[11]"KaiB functions as an attenuator of KaiC phosphorylation in the cyanobacterial circadian clock system."
Kitayama Y., Iwasaki H., Nishiwaki T., Kondo T.
EMBO J. 22:2127-2134(2003) [PubMed] [Europe PMC] [Abstract]
Cited for: ENZYME REGULATION, PHOSPHORYLATION, INTERACTION WITH KAIB.
[12]"Global gene repression by KaiC as a master process of prokaryotic circadian system."
Nakahira Y., Katayama M., Miyashita H., Kutsuna S., Iwasaki H., Oyama T., Kondo T.
Proc. Natl. Acad. Sci. U.S.A. 101:881-885(2004) [PubMed] [Europe PMC] [Abstract]
Cited for: FUNCTION OF THE KAIABC COMPLEX, INDUCTION.
[13]"Stoichiometric interactions between cyanobacterial clock proteins KaiA and KaiC."
Hayashi F., Ito H., Fujita M., Iwase R., Uzumaki T., Ishiura M.
Biochem. Biophys. Res. Commun. 316:195-202(2004) [PubMed] [Europe PMC] [Abstract]
Cited for: STOICHIOMETRY OF THE COMPLEX FORMED WITH KAIA.
[14]"Circadian rhythms in the synthesis and degradation of a master clock protein kaiC in cyanobacteria."
Imai K., Nishiwaki T., Kondo T., Iwasaki H.
J. Biol. Chem. 279:36534-36539(2004) [PubMed] [Europe PMC] [Abstract]
Cited for: DEVELOPMENTAL STAGE.
[15]"Visualizing a circadian clock protein; crystal structure of kaiC and functional insights."
Pattanayek R., Wang J., Mori T., Xu Y., Johnson C.H., Egli M.
Mol. Cell 15:375-388(2004) [PubMed] [Europe PMC] [Abstract]
Cited for: X-RAY CRYSTALLOGRAPHY (2.8 ANGSTROMS) OF HEXAMER, COFACTOR, MUTAGENESIS OF THR-432.
+Additional computationally mapped references.

Cross-references

Sequence databases

EMBL
GenBank
DDBJ
AB010691 Genomic DNA. Translation: BAA37103.1.
AY120853 Genomic DNA. Translation: AAM82686.1.
CP000100 Genomic DNA. Translation: ABB57246.1.
PIRT44269.
RefSeqYP_400233.1. NC_007604.1.

3D structure databases

PDBe
RCSB-PDB
PDBj
EntryMethodResolution (Å)ChainPositionsPDBsum
1TF7X-ray2.80A/B/C/D/E/F1-519[»]
1U9IX-ray2.80A/B/C/D/E/F1-519[»]
2GBLX-ray2.80A/B/C/D/E/F1-519[»]
3DVLX-ray2.80A/B/C/D/E/F1-519[»]
3JZMX-ray2.90A/B/C/D/E/F1-519[»]
3K09X-ray3.20A/B/C/D/E/F1-519[»]
3K0AX-ray3.00A/B/C/D/E/F1-519[»]
3K0CX-ray3.30A/B/C/D/E/F1-519[»]
3K0EX-ray3.20A/B/C/D/E/F1-519[»]
3K0FX-ray3.00A/B/C/D/E/F1-519[»]
3S1AX-ray3.00A/B/C/D/E/F1-519[»]
4DUGX-ray3.30A/B/C/D/E/F1-519[»]
4IJMX-ray3.35A/B/C/D/E/F14-519[»]
ProteinModelPortalQ79PF4.
SMRQ79PF4. Positions 14-519.
ModBaseSearch...
MobiDBSearch...

Protein-protein interaction databases

DIPDIP-33330N.
IntActQ79PF4. 3 interactions.
MINTMINT-8094424.
STRING1140.Synpcc7942_1216.

PTM databases

PhosSiteP0501119.

Protocols and materials databases

StructuralBiologyKnowledgebaseSearch...

Genome annotation databases

EnsemblBacteriaABB57246; ABB57246; Synpcc7942_1216.
GeneID3773504.
KEGGsyf:Synpcc7942_1216.
PATRIC23787739. VBISynElo51371_1398.

Organism-specific databases

CMRSearch...

Phylogenomic databases

eggNOGCOG0467.
HOGENOMHOG000230416.
KOK08482.
OrthoDBEOG6ZPSVX.

Enzyme and pathway databases

BioCycSYNEL:SYNPCC7942_1216-MONOMER.

Family and domain databases

Gene3D3.40.50.300. 2 hits.
HAMAPMF_01836. KaiC.
InterProIPR014774. Circ_KaiC/RadA.
IPR013503. Circadian_KaiC.
IPR010624. KaiC_dom.
IPR027417. P-loop_NTPase.
[Graphical view]
PfamPF06745. KaiC. 2 hits.
[Graphical view]
SUPFAMSSF52540. SSF52540. 2 hits.
TIGRFAMsTIGR02655. circ_KaiC. 1 hit.
PROSITEPS51146. KAIC. 2 hits.
[Graphical view]
ProtoNetSearch...

Other

EvolutionaryTraceQ79PF4.

Entry information

Entry nameKAIC_SYNE7
AccessionPrimary (citable) accession number: Q79PF4
Secondary accession number(s): Q31NX3, Q9Z3H2
Entry history
Integrated into UniProtKB/Swiss-Prot: October 11, 2004
Last sequence update: July 5, 2004
Last modified: June 11, 2014
This is version 96 of the entry and version 1 of the sequence. [Complete history]
Entry statusReviewed (UniProtKB/Swiss-Prot)
Annotation programProkaryotic Protein Annotation Program

Relevant documents

SIMILARITY comments

Index of protein domains and families

PDB cross-references

Index of Protein Data Bank (PDB) cross-references