Work Package 11 (ESR 12)

Modelling of circadian basis in photoperiodic response

General details

NetherlandsLocation
Universytet of Groningen (NL)

Supervisors
Dr Roelof Hut
Prof Domien G Beersma

ESR 12
Theresa Flößner

Other partners involved

Secondments

Ceské Budèjovice for 4 months in year 2 – training in Linden bug methodology for photoperiodicity experiments
Oxitec for 4 months in year 3 – training in Olive fly methodology for photoperiodicity experiments

Objectives

  • Develop a theoretical framework which will help designing latitudinal cline experiments
  • Develop a database for relevant regional climatic conditions to aid interpretation of latitudinal cline experiments, specifically the Nasonia data obtained in WP3 (Van der Zande, Groningen, 2).
  • Develop a test to distinguish species specific photoperiodic timing mechanisms.
  • Develop a general model to identify how these mechanisms result in latitudinal clines

Methods

  • Create models that give qualitative predictions for the lab experiments by month 20.
  • Design experimental procedures to test model predictions in the lab by month 26.
  • Translate model and experimental results to predictions for latitudinal clines by month 32

Description

Developing novel automated rhythmic behaviour analyses
We have recently modeled how two widely discussed yet putative mechanisms of photoperiodic induction, the internal and external coincidence models, yield different predictions for latitudinal clines in circadian period. Briefly the model predicts that external coincidence timing (in which a circadian driven photo-inducible phase gives a short day response, diapause, if it is not exposed to light), will generate a monotonous function between circadian period and latitude crossing the 24-h circadian period. Internal coincidence (in which two circadian oscillators, one synchronized by dawn, the other by dusk, which will have a small phase difference between them in short days, triggering diapause), would generate a parabolic function with a peak (or trough) at 24-h. This prediction will be tested in a number of insect species with a clear photoperiodic phenotype and a wide geographical distribution such as Nasonia and the linden bug (co-supervisor Dolezel). Critical photoperiod determination in strains of Drosophila with a wide range of circadian periods will be performed in collaboration with Kyriacou and Costa.

Results and milestones

Results:
1) Month 8 Project plan & personal development plan for individual training requirements
2) Month 14 Report of detailed research plans.
3) Month 26 Modelling results are being compared to experimental results; Plans for publication.
4) Month 36 At least one publication drafted.

Synergies, Risks & Exploitation

The modelers will require support from the insect laboratories to test their predictions. Risks, perhaps the results may not fit the models so models will need elaboration. Modelling is of interest to all partners, but particularly to SMEs Oxitec and Biofly who can use model predictions to modify their experimental and release procedures.

See more Work Packages in Research Area C