Projects per year
Circadian rhythms are ubiquitous in eukaryotes, and coordinate numerous aspects of behaviour, physiology and metabolism, from sleep/wake cycles in mammals to growth and photosynthesis in plants. This daily timekeeping is thought to be driven by transcriptional-translational feedback loops, whereby rhythmic expression of 'clock' gene products regulates the expression of associated genes in approximately 24-hour cycles. The specific transcriptional components differ between phylogenetic kingdoms. The unicellular pico-eukaryotic alga Ostreococcus tauri possesses a naturally minimized clock, which includes many features that are shared with plants, such as a central negative feedback loop that involves the morning-expressed CCA1 and evening-expressed TOC1 genes. Given that recent observations in animals and plants have revealed prominent post-translational contributions to timekeeping, a reappraisal of the transcriptional contribution to oscillator function is overdue. Here we show that non-transcriptional mechanisms are sufficient to sustain circadian timekeeping in the eukaryotic lineage, although they normally function in conjunction with transcriptional components. We identify oxidation of peroxiredoxin proteins as a transcription-independent rhythmic biomarker, which is also rhythmic in mammals. Moreover we show that pharmacological modulators of the mammalian clock mechanism have the same effects on rhythms in Ostreococcus. Post-translational mechanisms, and at least one rhythmic marker, seem to be better conserved than transcriptional clock regulators. It is plausible that the oldest oscillator components are non-transcriptional in nature, as in cyanobacteria, and are conserved across kingdoms.
|Number of pages||5|
|Publication status||Published - 2011|
- Biological Markers
- Circadian Rhythm
- Gene Expression Regulation
- Protein Synthesis Inhibitors
- Transcription, Genetic
FingerprintDive into the research topics of 'Circadian rhythms persist without transcription in a eukaryote'. Together they form a unique fingerprint.
- 2 Finished
Miinimal models of the circadian clock in a novael biological system
1/12/07 → 31/05/11
SynthSys; formerly CSBE: Centre for Systems Biology at Edinburgh
Millar, A., Beggs, J., Ghazal, P., Goryanin, I., Hillston, J., Plotkin, G., Tollervey, D., Walton, A. & Robertson, K.
8/01/07 → 31/12/12
- 1 Article
Non-transcriptional oscillators in circadian timekeepingvan Ooijen, G. & Millar, A. J., 1 Nov 2012, In: Trends in biochemical sciences. 37, 11, p. 484-492 9 p.
Research output: Contribution to journal › Article › peer-review
Study of plants may reveal the impact of jet lag and shift work on people
14 items of Media coverage
Research breakthrough could help combat illnesses related to the disruption of the body clock
12 items of Media coverage