Synchronous and opponent thermosensors use flexible cross-inhibition to orchestrate thermal homeostasis
Luis Hernandez-Nunez, Alicia Chen, Gonzalo Budelli, Matthew Berck, Vincent Richter, Anna Rist, Andreas S. Thum, Albert Cardona, Mason Klein, Paul Garrity, Aravinthan D. T. Samuel
Abstract
WCs and CCs detect temperature changes using overlapping combinations of ionotropic receptors: Ir68a, Ir93a, and Ir25a for WCs and Ir21a, Ir93a, and Ir25a for CCs. WCs mediate avoidance to warming while cross-inhibiting avoidance to cooling, and CCs mediate avoidance to cooling while cross-inhibiting avoidance to warming. Ambient temperature-dependent regulation of the strength of WC- and CC-mediated cross-inhibition keeps larvae near their homeostatic set point. Using neurophysiology, quantitative behavioral analysis, and connectomics, we demonstrate how flexible integration between warming and cooling pathways can orchestrate homeostatic thermoregulation.