Biophysical clocks face a trade-off between internal and external noise resistance
Many organisms use free running circadian clocks to anticipate the day night cycle. However, others organisms use simple stimulus-response strategies ('hourglass clocks') and it is not clear when such strategies are sufficient or even preferable to free running clocks. Here, we find that free running clocks, such as those found in the cyanobacterium Synechococcus elongatus and humans, can efficiently project out light intensity fluctuations due to weather patterns ('external noise') by exploiting their limit cycle attractor. However, such limit cycles are necessarily vulnerable to 'internal noise'. Hence, at sufficiently high internal noise, point attractor-based 'hourglass' clocks, such as those found in a smaller cyanobacterium with low protein copy number, Prochlorococcus marinus, outperform free running clocks. By interpolating between these two regimes in a diverse range of oscillators drawn from across biology, we demonstrate biochemical clock architectures that are best suited to different relative strengths of external and internal noise.
The code and data used in the simulations are available via Github https://github.com/WeerapatP/elife_tradeoff_clocks
Article and author information
- Arvind Murugan
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
- Aleksandra M Walczak, École Normale Supérieure, France
- Received: April 17, 2018
- Accepted: June 23, 2018
- Accepted Manuscript published: July 10, 2018 (version 1)
- Version of Record published: July 25, 2018 (version 2)
© 2018, Pittayakanchit et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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