Unraveling the circadian puzzle: the role of different groups of clock neurons in the control of the oviposition rhythm in Drosophila melanogaster

RIVA, SABRINA; RISAU-GUSMAN, SEBASTIAN; FRANCO, D. LORENA

Buenos Aires

Simposio; Frontiers in Bioscience 4 Symposium; 2023

The cyclic succession ofday and night has led many living organisms to develop an internal"clock" that allows them to anticipate environmental changes for betteradaptation. In Drosophila melanogaster, approximately 150 neurons functioningas circadian oscillators have been identified, as the clock components in theseneurons fluctuate with a period close to 24 hours. These neurons are located inthe lateral and dorsal regions of the brain, referred to as lateral neurons(LN) and dorsal neurons (DN), respectively. The lateral neurons can be dividedinto ventral lateral neurons (LNvs), which include small and large neurons, anddorsal lateral neurons (LNds). On the other hand, the dorsal neurons aregrouped into three known clusters: DN1, DN2, and DN3.The egg-laying behavior,or oviposition, is a physiological process under the control of the circadianclock. The periodicity of oviposition is one of the least studied rhythms inDrosophila, and many important aspects related to the role of different groupsof circadian neurons in controlling this behavior still need to be elucidated.To test this, we silenced the molecular clock of each group of neurons thatmake up the circadian network. By monitoring the rhythmicity of egg-layingbehavior, we confirmed their importance in behavior control. We found thatneither the ventral lateral neuron group (sLNv) nor the dorsal neuron group(DN1) are individually relevant for regulating the rhythmicity of egg-laying.However, the group of dorsal lateral neurons (LNds) proved to be significant inregulating the rhythmicity of behavior, as silencing the clock in these neuronsled to a loss of rhythmicity in egg-laying. This suggests that this group ofclock neurons plays a central role in regulating the rhythmicity of this behavior