Work Package 9 (ESR 10)

Seasonal light input

General details

Location
FranceCNRS, France

Supervisors
Dr Francois Rouyer

ESR 10
Faredin Alejevski

Other partners involved
Queen Mary University, UK

Secondments

Actual Analytics for 4 months at the beginning of year 3 – training in software analysis of video-recorded activity

Objectives

  • Determine how visual system and PDF signalling interact to adapt the activity pattern to daylength changes
  •  Identify qualitative differences between morning and evening activities in light-dark cycles

Methods

  • Produce genotypes with combinations of PDF, CRY, and visual system mutations in flies with PER expression restricted to clock neurons subsets for behavioral adaptation to daylength (month 12)
  • Analyze genotypes in light-dark cycles of different daylengths and temperature cycles (month 24)
  • Record morning and evening activities with a video-based system to identify specific behaviors (month 36)

Description

Adaptation of the circadian neuronal network to seasonal changes of light inputs in Drosophila

Our project aims to decipher how light and PDF influence the behavioural contributions of the E oscillators located in the lateral and the dorsal groups of clock neurons (DNs), that have recently been shown to contribute to both M and E activity. Flies carrying different combinations of the three identified oscillators (M, E and DNs) in the presence or the absence of PDF signalling will be entrained in short or long days, and will be analyzed for the distribution of their locomotor activity. Light control will be investigated by applying two different light intensities and either white light or red light to turn ON and OFF the contribution of the blue-light circadian photoreceptor, cryptochrome. This will be further analyzed by introducing temperature changes to the entrainment conditions. Significant inputs to this project will also be provided by Rosato (DNs function), Pyza (deciphering the role of light) and comparing our results with those of studies performed previously in natural conditions (Kyriacou, Costa). We are also anxious to analyse locomotor activity at much higher resolution than is presently practised, by developing software tools with Actual Analytics. For example, we have not been able to distinguish the M behaviour of wild-type flies, from that observed in flies which have only an intact M oscillator, nor the E behaviour of wild-type flies from that of flies expressing only the E oscillator. Our neurogenetic results suggest a cross-talk between the M and E oscillators that should be detectable in the behaviour of the M or E only flies. A video-based approach, rather than our current light-beam interruption method, may be more sensitive. Understanding whether the different circadian oscillators encode components other than gross activity levels would represent a significant advance in the clock field.

Results and milestones

1) Month 8: Project plan & personal development plan for individual training requirements
2) Month 14 Report of experimental results and plans for publication
3) Month 26 Report of detailed research plans, first results, and potential experimental problems
4) Month 36 Publication drafted

Synergies, Risks & Exploitation

Light (CNRS) and temperature (Queen Mary) expertise generates an integrated picture of summer and winter phenotypes. Actual will allow discrimination of behavioural subtleties previously missed. Risks, minimal. How insects switch between summer or winter phenotypes would be very useful for our SMEs in intervening in life cycles of economically important insect pests. Commercialisation of Actual algorithms.

See more Work Packages in Research Area B