title: Robust circadian oscillations in growing cyanobacteria require transcriptional feedback.
abstract: The remarkably stable circadian oscillations of single cyanobacteria enable a population of growing cells to maintain synchrony for weeks. The cyanobacterial pacemaker is a posttranslational regulation (PTR) circuit that generates circadian oscillations in the phosphorylation state of the clock protein KaiC. Layered on top of the PTR is transcriptional-translational feedback regulation (TTR), common to all circadian systems, consisting of a negative feedback loop in which KaiC regulates its own production. We found that the PTR circuit is sufficient to generate oscillations in growing cyanobacteria. However, in the absence of TTR, individual oscillators were less stable and synchrony was not maintained in a population of cells. Experimentally constrained mathematical modeling reproduced sustained oscillations in the PTR circuit alone and demonstrated the importance of TTR for oscillator synchrony.
authors: Howard Hughes Medical Institute, Faculty of Arts and Sciences Center for Systems Biology, Department of Molecular and Cellular Biology, Harvard University, Cambridge, MA 02138, USA.
authors: Shu-Wen
authors: SW
authors: Teng
authors: Shankar
authors: S
authors: Mukherji
authors: Jeffrey R
authors: JR
authors: Moffitt
authors: Sophie
authors: S
authors: de Buyl
authors: Erin K
authors: EK
authors: O'Shea
mesh_terms: D002940:Circadian Rhythm / Q000235:genetics*; D025461:Feedback, Physiological; D014176:Protein Biosynthesis; D046940:Synechococcus / Q000235:genetics / Q000502:physiology*; D014158:Transcription, Genetic
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