Defining all principal components of a neural circuit, from sensory transduction to behavior, is one of the fundamental goals of neuroscience. While this presents a monumental challenge for a mammalian brain; the simpler nervous system, rich repertoire of innate behaviors, and unparalleled genetic tractability of Drosophila melanogaster afford a rare opportunity to uncover fundamentals of neural processing. To this end, our laboratory focuses on understanding how the processing of temperature stimuli in the Drosophila brain produces the appropriate aversive and attractive responses. The ability to sense temperature, thermosensation, provides organisms with critical information; yet it is one of the least understood sensory modalities. In Drosophila, rapid temperature changes are detected by dedicated hot and cold temperature receptors in the antenna, with 3 neurons responding to cooling and 3 neurons responding to heating. The axons of these cells terminate in segregated, adjacent 'hot' and 'cold' glomeruli in the brain; forming a topographic map for the representation of temperature, as demonstrated by calcium imaging. It is unclear how this spatial map of activity is processed by higher brain regions to direct behaviors. Here, I propose to map the transformation of temperature information in the Drosophila brain from sensory detection to the triggering of specific motor programs. This work will provide fundamental insights into high- level sensorimotor neuronal computations in a relatively simple system and may help explain how the brain processes all innate behaviors. In conducting these experiments, I will learn how to perform genetically targeted optogenetic stimulation with tandem two-photon optical recording and behavioral assays. Further, I will be trained in executive scientific skills such as experimental design, scientific communication, and professional networking.
A great deal of progress has revealed much on how sensory systems detect and process environmental variables, yet we know much less on the sensory-motor transformations that occur in the brain to produce goal-directed behavior. Thermosensation is likely one of the most ancient sensory modalities, yet still remains one of the least understood. Here, I propose to apply a series of neurogenetic and imaging approaches to study how hot and cold stimuli are processed to produce temperature preference in the brain of Drosophila melanogaster.
| Frank, Dominic D; Enjin, Anders; Jouandet, Genevieve C et al. (2017) Early Integration of Temperature and Humidity Stimuli in the Drosophila Brain. Curr Biol 27:2381-2388.e4 |
| Enjin, Anders; Zaharieva, Emanuela E; Frank, Dominic D et al. (2016) Humidity Sensing in Drosophila. Curr Biol 26:1352-8 |
