The Drosophila Clock System



The present chapter describes the circadian clock system in fruit flies starting with the molecular mechanisms that generate circadian rhythms and then moving to the organismic level, whereby most importance is given to the clock network in the brain. It is shown that the molecular clock controls neuronal excitability and synaptic plasticity of the clock neurons in the brain, that these clock neurons communicate with each other via neuropeptides, and that they have different roles in controlling activity rhythms. The mechanisms by which the clock in the brain is entrained to light and temperature cycles are explained as well as the known output pathways by which it controls behavior. The chapter ends by discussing the significance of the clock as well as its immediate and evolutionary adaptations to different environmental conditions. Throughout the chapter, comparisons are made to the circadian system of other species.


Drosophila melanogaster Molecular clock mechanisms Circadian clock neurons Entrainment to light and temperature cycles Circadian output pathways Evolutionary clock adaptations 



I thank Ezio Rosato, Taishi Yoshii, Pamela Menegazzi, and Christiane Hermann-Luibl for their discussions and useful comments on this chapter and Marta Beauchamp for the language editing. Furthermore, I thank the German Research Foundation, the DFG, and the EU for continuously funding the research of my group.


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© Springer (India) Pvt. Ltd. 2017

Authors and Affiliations

  1. 1.Lehrstuhl für Neurobiologie und GenetikUniversitaet Wuerzburg, BiozentrumWuerzburgGermany

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