Abstract:
Animals adapt their behavior to meet a variety of internal needs. A vital example is the need to eat and ingest the appropriate nutrient composition to maintain nutrient homeostasis by fulfilling current or anticipated nutrient requirements. Hunger and appetite for specific nutrients are driven by internal states like nutrient and mating states. How internal states act to modulate behavior remains poorly understood.
Using volumetric 2-photon imaging, we created a functional atlas of the subesophageal zone (SEZ), the first taste processing center in the Drosophila brain. We found that protein deprivation shapes sensorimotor processing across large sections of the neuropil. In contrast, reproductive state, although also driving protein appetite, resulted in a more focused modulation of regions related to feeding motor output. Employing a novel computational strategy, we identify driver lines that label neurons that innervate state-modulated brain regions. We show that the newly identified ‘borboleta’ region is sufficient to direct food choice towards protein-rich food.
Interestingly, carbohydrate deprivation results in the modulation of different regions within the SEZ, indicating that distinct neural circuits are engaged based on the specific nutrient deficit. These findings underscore how nutrient-specific needs dynamically shape sensory information processing in the brain to guide homeostatic behaviors.