CikA, a Bacteriophytochrome That Resets the Cyanobacterial Circadian Clock

Science. 2000 Aug 4;289(5480):765-8. doi: 10.1126/science.289.5480.765.

Abstract

The circadian oscillator of the cyanobacterium Synechococcus elongatus, like those in eukaryotes, is entrained by environmental cues. Inactivation of the gene cikA (circadian input kinase) shortens the circadian period of gene expression rhythms in S. elongatus by approximately 2 hours, changes the phasing of a subset of rhythms, and nearly abolishes resetting of phase by a pulse of darkness. The CikA protein sequence reveals that it is a divergent bacteriophytochrome with characteristic histidine protein kinase motifs and a cryptic response regulator motif. CikA is likely a key component of a pathway that provides environmental input to the circadian oscillator in S. elongatus.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Alleles
  • Amino Acid Motifs
  • Amino Acid Sequence
  • Bacterial Proteins*
  • Biological Clocks* / genetics
  • Biological Clocks* / physiology
  • Circadian Rhythm* / genetics
  • Circadian Rhythm* / physiology
  • Cyanobacteria / genetics
  • Cyanobacteria / physiology*
  • Gene Expression Regulation, Bacterial
  • Genes, Bacterial
  • Genes, Reporter
  • Luminescent Measurements
  • Molecular Sequence Data
  • Mutation
  • Phenotype
  • Protein Kinases / chemistry
  • Protein Kinases / genetics*
  • Protein Kinases / physiology
  • Sequence Alignment

Substances

  • Bacterial Proteins
  • Protein Kinases
  • CikA protein, bacteria

Associated data

  • GENBANK/AF258464