Insulin Producing Cells Monitor the Cold and Compensate the Cold-Induced Sleep in Drosophila

Abstract

Sleep is regulated by environmental factors including temperature, but the neural circuits that receive the sensory signal and mediate the regulation remain unclear. We examined how cold could influence Drosophila sleep patterns and its neural mechanism. The results showed that Drosophila has more sleep duration, less sleep latency and deeper sleep depth under cold condition. We identified the Insulin-producing Cells (IPCs) can be activated by cold, and receive the cold signal from the 11216 cold-sensing neuron without a direct synaptic connection. Elevation of IPCs' sensitivity to cold impairs the sleeppromoting effect of cold while blocking of IPCs enhance the effect mostly on sleep circadian, suggesting that the cold activated IPCs have a compensative role in sleep regulation. Our finding revealed a potential neural circuit that help maintain sleep circadian in detrimental environment and may give new insight to the complicated sleep regulation mechanism.

Neuroendocrine Regulation of Reproductive Dormancy in the Fruit Fly Drosophila melanogaster: A Review of Juvenile Hormone-Dependent Regulation

“…Since a lower level of feeding results in the suppression of energy expenditure, the dormancy-inducing low temperature might negatively affect IPC activity, possibly leading to reproductive dormancy. Meanwhile, curiously and paradoxically, some studies have reported that IPCs are activated by cold-sensing neurons at 18 • C rather than 25 • C (Li and Gong, 2015;Zhang et al, 2019), whereas the function of cold-sensing neurons in dormancy-inducing conditions has not yet been investigated. Further studies will be needed to clarify how low temperatures influence IPC activity to induce reproductive dormancy.…”