View Program - 63rd Annual Drosophila Research Conference

Glial cells are essential components of the nervous system that shape neural circuits underlying behavior. Many previous studies have found an important function for glia in the regulation of extracellular ion concentrations that affect neuronal excitability. To better understand how glial effects on ion gradients might affect neurons, we manipulated glial ion gradients using the GAL4/UAS system. Specifically, we expressed the light-gated anion channel GtACR1 or the thermal-gated cation channel dTRPA1 in glia and recorded immediate motor behaviors that occurred following light or thermal activation of the channel. Interestingly, a full body contraction was seen upon activating GtACR1 in glia. In contrast, activating dTRPA1 in glia triggered an apparently opposite behavior of full body relaxation and complete immobility. To rule out the possibility that leaky ion channel expression in neurons was the basis of these motor behaviors, we used GAL80 to prevent neuronal populations from expressing GtACR1 or dTRPA1. In both cases, the behaviors persisted, supporting that glia (and not unintended neuronal expression) contribute to the motor behaviors. To identify which glial subtype(s) produced the accordion phenotype and full body relaxation, we expressed GtACR1 and dTRPA1 in various glial populations. We found that GtACR1 expression in the perineurial and subperineurial glia produced the accordion phenotype, and dTRPA1 expression in the cortex, ensheathing, and wrapping glia produced the full body relaxation. Our results support that changes in glial ion gradients allow glia to directly influence the production of motor outputs.

Molecular mechanism glia use to contribute to the production of motor outputs in Drosophila