Work Package 6 (ESR 7)

Clock networks in insects

General details

GermanyLocation
University of Wuerzburg, DE

Supervisors
Prof. C. Helfrich-Förster

ESR 7
Enrico Bertolini

Other partners involved
Biologicke centrum AV CR, v.v.i.
Czech Republic

Secondments

Biologicke centrum AV CR, v.v.i. for 2 months in year 1 – training in Linden bug biology and methodology
Oxitec for 2 months in year 2 – training Olive fly biology and methodology
University of Leicester for 2 months in year 3 – training on diapausing paradigms and Nasonia biology

Objectives

  • Anatomical/functional analysis of clock network in Nasonia, Chymomyza, Pyrrhocoris and Bactrocerca
  • Study role of M and E-cells for adaptations to natural-like long- and short-days in Drosophila melanogaster

Methods

  • Test available antibodies and design RNAi constructs for all species by month 18
  • Finish behavioural experiments on Drosophila
  • Describe the clock network in the 4 insect species by month 30
  • Finish the functional characterisation of clock neurons in the 4 insect species by month 36

Description

Comparative neurogenetic analysis of seasonal circadian adaptation in D. melanogaster
To study the regulation of diapause predicted by the internal coincidence model in insects with clear photoperiodic diapause such as Nasonia, ChymomyzaPyrrhocoris and Bactrocerca, the first step will be the characterisation of the clock network in these insects by ICC using antibodies against the neuropeptides PDF and Ion Transport Peptide (ITP). In Drosophila, PDF is used as a neurotransmitter by the M-neurons and ITP by the E-neurons. Since neuropeptide use is highly conserved in insects, we expect that the two antibodies will reliably reveal putative M and E oscillators in the selected species. The second step will be the knock-down of clock or neuropeptide genes by RNAi, and testing any effects on both activity rhythms and diapauses. These latter experiments will represent collaborations with Groningen, Ceske, and Oxitec. Mutants that express PER in just four M- or four E-neurons (in contrast to the full set of 150) behave astonishingly normally under certain light-conditions in the laboratory; but it is not clear whether they can adapt to seasonal changes. The two-oscillator model would predict they cannot. To challenge the model, we will investigate behavioural rhythmicity and clock-protein cycling in these flies in nature as well as under simulated laboratory natural short- and long-day conditions. We will also study the seasonal diapause response. Rouyer, Stanewsky, Pyza and Kyriacou will also be involved regarding M and E cells, photoreceptor and thermal input, natural entrainment and diapause. Actual Analytics will be involved in monitoring subtle behavioural changes that cannot be detected in the conventional behavioural assays. We will model the behavioural results in cooperation with Beersma and Hut.

Results and milestones

1) Month 8 Project plan & personal development plan for individual training requirements
2) Month 14 Report of detailed research plans
3) Month 26 Report of experimental results and plans for publication
4) Month 36 At least one publication drafted.

Synergies, Risks & Exploitation

The partners bring different expertise to the project, providing a multidimensional enhancement of
the biology. Risks, RNAi in non-models insects can be difficult but has been successful in these species. The comparative mapping of functional neuronal networks in these non-model species are important for understanding potential weaknesses of economically important insects by the SMEs. New algorithms will be marketed by Actual.

See more Work Packages in Research Area B