Synchronization of sleep-wake rhythms by the visual system in Drosophila
Dates:18 September 2017 - 29 June 2018
Date limite de candidature:29 June 2018
~ Sept-Dec 2017
~ Jan-March 2018
~ April-June 2018
Brain circadian clocks control sleep-wake cycles. In Drosophila, the brain clock relies on a network of about 150 neurons that show oscillations of clock gene expression. Different subsets of clock neurons contribute to specific behavioral components and use sensory inputs such as light and temperature to synchronize with day-night cycles. The clock perceive light through either the intrinsic photoreceptive molecule cryptochrome or six rhodopsins that are distributed in three photoreceptive structures: compound eye, Hofbauer-Buchner eyelet, and ocelli. One major goal of the lab is to identify and define the properties of the neuronal circuits that connect photoreceptors to the clock network. Histamine is the neurotransmitter of insect photoreceptors and our results show that each of the two histamine-gated chloride channels (ORT and HISCL1) is used by first-order interneurons, as well as cells recently identified in the lab, to collect light information from the photoreceptors. The project will aim at characterizing the specific function of each of the two histamine receptors in the different circuits that bring light information to the different groups of clock neurons. Drosophila neurogenetic tools will be used to study combinations of specific rhodopsins, histamine receptors and clock neurons in order to understand how specific light input circuits allows the adaptation of the sleep-wake behavior to the daily changes of the environment. Anatomical (characterization of interneurons and their associations with upstream photoreceptors and downstream clock neurons) as well as functional (connectivity assays based on calcium imaging in the neurons) analyses will be performed to probe the relevant circuits.
Institut des Neurosciences Paris-Saclay (Neuro-PSI) - Bât. 32/33, 1 Av. de la Terrasse, 91190 Gif-sur-Yvette - firstname.lastname@example.org