The browser you are using is not supported by this website. All versions of Internet Explorer are no longer supported, either by us or Microsoft (read more here: https://www.microsoft.com/en-us/microsoft-365/windows/end-of-ie-support).

Please use a modern browser to fully experience our website, such as the newest versions of Edge, Chrome, Firefox or Safari etc.

Profile picture. Photo.

Carl Troein

Researcher

Profile picture. Photo.

Light and circadian regulation of clock components aids flexible responses to environmental signals

Author

  • Laura E. Dixon
  • Sarah K. Hodge
  • Gerben van Ooijen
  • Carl Troein
  • Ozgur E. Akman
  • Andrew J. Millar

Summary, in English

The circadian clock measures time across a 24h period, increasing fitness by phasing biological processes to the most appropriate time of day. The interlocking feedback loop mechanism of the clock is conserved across species; however, the number of loops varies. Mathematical and computational analyses have suggested that loop complexity affects the overall flexibility of the oscillator, including its responses to entrainment signals. We used a discriminating experimental assay, at the transition between different photoperiods, in order to test this proposal in a minimal circadian network (in Ostreococcus tauri) and a more complex network (in Arabidopsis thaliana). Transcriptional and translational reporters in O.tauri primarily tracked dawn or dusk, whereas in A.thaliana, a wider range of responses were observed, consistent with its more flexible clock. Model analysis supported the requirement for this diversity of responses among the components of the more complex network. However, these and earlier data showed that the O.tauri network retains surprising flexibility, despite its simple circuit. We found that models constructed from experimental data can show flexibility either from multiple loops and/or from multiple light inputs. Our results suggest that O.tauri has adopted the latter strategy, possibly as a consequence of genomic reduction.

Department/s

  • Computational Biology and Biological Physics - Undergoing reorganization

Publishing year

2014

Language

English

Pages

568-577

Publication/Series

New Phytologist

Volume

203

Issue

2

Document type

Journal article

Publisher

Wiley-Blackwell

Topic

  • Biophysics
  • Other Physics Topics

Keywords

  • biological clocks
  • flexibility
  • marine algae
  • mathematical analysis
  • nonlinear dynamics
  • photoperiod
  • systems biology

Status

Published

ISBN/ISSN/Other

  • ISSN: 1469-8137