Light and circadian regulation of clock components aids flexible responses to environmental signals
Författare
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.
Publiceringsår
2014
Språk
Engelska
Sidor
568-577
Publikation/Tidskrift/Serie
New Phytologist
Volym
203
Issue
2
Dokumenttyp
Artikel i tidskrift
Förlag
Wiley-Blackwell
Ämne
- Biophysics
- Other Physics Topics
Nyckelord
- biological clocks
- flexibility
- marine algae
- mathematical analysis
- nonlinear dynamics
- photoperiod
- systems biology
Status
Published
ISBN/ISSN/Övrigt
- ISSN: 1469-8137