Downregulation of a GABA receptor affects sleep behavior in unanticipated ways in Drosophila

FLORENCIA FERNANDEZ; NARA I MURARO

Valparaiso

Congreso; XIV Latin American Symposium on Chronobiology -LASC 2017; 2017

XIV LASC Organizing Committee

Sleep is a complex andvital behavior regulated by both, circadian and homeostatic mechanisms.  The neural circuits involved in sleephomeostasis are not well described yet, but it has been proposed that GABAergicinputs to the large lateral ventral neurons (lLNvs) of the adult brain of Drosophila melanogaster may have therole of informing those highly integrative circadian and arousal neurons aboutthe sleep homeostat status.Starting from thispoint, our aim was to study GABAergic inhibition on LNvs, its influence onsleep behavior and its role on the sleep homeostat. For this, we quantifiedsleep behavior by inferring it from locomotor activity under basal and sleepdeprivation conditions. In addition, we studied the levels of Pigment DispersingFactor in the axonal projections of the lLNvs in order to evidence the effectover neuronal outputs under those circumstances. Finally, we are currentlyperforming electrophysiological recordings to identify the extent of the roleof the neurotransmitter GABA in the neuronal circuit studied.Our findings indicate that downregulation of the GABAA receptor Rdl in LNvs affects sleep behavior in the way it was reported.Moreover, we have now confirmed its previously suggested role on the sleephomeostat. However, we have surprisingly found thatsleep can be differentially affected by the downregulation of Rdl in the LNvs when the genetic manipulation is performed ina constitutive or an acute fashion. This indicates that compensation played an important part on previously reported phenotypesand opens unexpected possibilities of theactual mechanism of action involved.