A cyanobacterial circadian timing mechanism.

@article{Ditty2003ACC,
  title={A cyanobacterial circadian timing mechanism.},
  author={Jayna L. Ditty and S. B. Williams and Susan S. Golden},
  journal={Annual review of genetics},
  year={2003},
  volume={37},
  pages={
          513-43
        }
}
Cyanobacteria such as Synechococcus elongatus PCC 7942 exhibit 24-h rhythms of gene expression that are controlled by an endogenous circadian clock that is mechanistically distinct from those described for diverse eukaryotes. Genetic and biochemical experiments over the past decade have identified key components of the circadian oscillator, input pathways that synchronize the clock with the daily environment, and output pathways that relay temporal information to downstream genes. The mechanism… 
Winding up the cyanobacterial circadian clock.
TLDR
The mechanisms by which S. elongatus maintains internal time are reviewed, how external stimuli affect this oscillation is discussed, and the mechanisms underlying circadian controlled cellular events are evaluated.
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TLDR
This work provides the first unbiased characterization of circadian gene expression in S. elongatus, demonstrating that ~65% of genes display oscillation in continuous light conditions, with some genes peaking in expression at subjective dawn and others at subjective dusk.
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TLDR
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TLDR
The research presented in this dissertation explores the regulatory mechanisms that exist at each level of the clock system and depicts the internal timekeeping elements KaiA, KaiB, and KaiC interacting with one another to form a large, multimeric complex that assembles and disassembled over the course of a day.
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TLDR
Analysis of 11,264 genomes clearly demonstrates that components of the Synechococcus elongatus PCC 7942 circadian clock are present in Bacteria and Archaea, and proposes putative networks of reduced and fully functional clock systems.
Minimal tool set for a prokaryotic circadian clock
TLDR
An analysis of 11,264 genomes clearly demonstrates that components of the Synechococcus elongatus PCC 7942 circadian clock are present in Bacteria and Archaea, and identifies putative KaiC-based timing systems in organisms outside as well as variations within Cyanobacteria.
Circadian Timing Mechanism in the Prokaryotic Clock System of Cyanobacteria
TLDR
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Oscillations in supercoiling drive circadian gene expression in cyanobacteria
TLDR
It is shown that the topological status of the chromosome is highly correlated with circadian gene expression state and that perturbation of superhelical status within the physiological range elicits global changes in gene expression similar to those that occur during the normal circadian cycle.
Integrating the circadian oscillator into the life of the cyanobacterial cell.
  • S. Golden
  • Biology, Medicine
    Cold Spring Harbor symposia on quantitative biology
  • 2007
TLDR
With sophisticated biochemical, biophysical, genetic, and genomic tools in place, the circadian clock of the unicellular cyanobacterium Synechococcus elongatus is poised to be the first for which a systems-level understanding can be achieved.
Proteins Found in a CikA Interaction Assay Link the Circadian Clock, Metabolism, and Cell Division in Synechococcus elongatus
TLDR
Phenotypic analyses of null and overexpression alleles demonstrate that four proteins are involved in at least one of the functions--circadian period regulation, phase resetting, and cell division--attributed to CikA, and predictions based on sequence similarity suggest that these proteins function through protein phosphorylation, iron-sulfur cluster biosynthesis, and redox regulation.
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