Peptidergic top-down control of metabolic state-dependent behavioral decisions in a conflicting sensory context

Abstract

Animals make economically beneficial behavioral decisions by integrating the external sensory environment with their internal state. The metabolic state, i.e. hunger, can shift priorities, prompting risk-taking and reducing responses to danger during foraging activities. How behavioral changes are processed in the nervous system to generate flexible responses based on needs and risks remains largely unclear. Here, we demonstrate in Drosophila larvae that the corticotropin releasing hormone (CRH) homolog diuretic hormone 44 (Dh44) and its producing neurons exert metabolic top-down control of behavioral choice in a conflicting sensory context. The metabolic state via Dh44 signaling mediates the transition from avoiding to tolerating aversive light conditions in the presence of food. In vivo imaging of neuropeptide release revealed that Dh44 regulates the acute release of Insulin-like peptide 7 (Ilp7) specifically in a conflicting context, thereby inducing light tolerance. Optogenetic activation of specific subsets of Dh44 or Ilp7 producing neurons during starvation is sufficient to shift behavior from light tolerance to avoidance by regulating light avoidance circuit responses. This top-down feedforward peptidergic circuit may represent a general mechanism that helps organisms to balance risk-taking with metabolic needs by allowing flexible adjustment of behavior in a conflicting multisensory environment.