Circuit and Behavioral Basis of Egg-Laying Site Selection in Drosophila melanogaster

Abstract

<p>One of the outstanding goals of neuroscience is to understand how neural circuits are assembled to produce context appropriate behavior. In an ever changing environment, it is critical for animals to be able to flexibly respond to different stimuli to optimize their behavioral responses accordingly. Oviposition, or the process of choosing where to lay eggs, is an important behavior for egg-laying animals, yet the neural mechanisms of this behavior are still not completely understood. Here, we use the genetically tractable organism, Drosophila melanogaster, to investigate how the brain decides which substrates are best for egg deposition. We show that flies prefer to lay eggs away from UV light and that induction egg-laying correlates with increased movement away from UV. Both egg-laying and movement aversion of UV are mediated through R7 photoreceptors, but only movement aversion is mediated through Dm8 amacrine neurons. We then identify octopaminergic neurons as being potential modulators of egg-laying output. Collectively, this work reveals new insights into the neural mechanisms that govern Drosophila egg-laying behavior.</p>