Mechanism underlying starvation-dependent modulation of olfactory behavior in Drosophila larva

Abstract

38Starvation enhances olfactory sensitivity that encourage animals to search for food. The 39 molecular mechanisms that enable sensory neurons to remain flexible and adapt to a particular 40 internal state remain poorly understood. Here, we study the roles of GABA and insulin signaling 41 in starvation-dependent modulation of olfactory sensory neuron (OSN) function in the 42Drosophila larva. We show that GABAB-receptor and insulin-receptor are necessary for OSN 43 modulation. Using a novel OSN-specific gene expression analysis, we explore downstream 44 targets of insulin signaling in OSNs. Our results strongly suggest that insulin and GABA 45 signaling pathways interact within OSNs and modulate OSN function by impacting olfactory 46 information processing and neurotransmission. We further show that manipulating these 47 signaling pathways specifically in the OSNs impact larval feeding behavior and its body weight. 48These results challenge the prevailing model of OSN modulation and highlight opportunities to 49 better understand OSN modulation mechanisms and their relationship to animal physiology. 50 51

Dscam1 overexpression impairs the function of the gut nervous system in Drosophila

“…Larval locomotor behavior can be influenced by feeding state, as larvae with eating impairments display wandering behavior, 42 and starved larvae displaying increased locomotion and altered foraging strategies 43‐45 . We tested the effect on distance traveled and the average speed of larvae over‐expressing full‐length Dscam1 and Dscam1‐ΔC (Figure 7A).…”

“…Larval locomotor behavior can be influenced by feeding state, as larvae with eating impairments display wandering behavior, 42 and starved larvae displaying increased locomotion and altered foraging strategies. [43][44][45] We tested the effect on distance traveled and the average speed of larvae over-expressing full-length Dscam1 and Dscam1-ΔC (Figure 7A). 46,47 Dscam1 over-expressing larvae showed a decrease in average speed compared to control larvae when the Ret-P2A and -P2B drivers were used (Figure 7B).…”

Modality specific roles for metabotropic GABAergic signaling and calcium induced calcium release mechanisms in regulating cold nociception

“…In neonatal hippocampal cultures, GABA B receptors have been shown to colocalize with G αq and function through IP 3 R and PKCα enhancing L-type Ca 2+ current (Karls & Mynlieff, 2015). Additionally, GABA B receptors are required in olfactory sensory neuron for Drosophila larval feeding responses (Slankster et al, 2020). These recent findings, including our reported findings, support new emerging roles for GABA B receptors in signaling pathways promoting stimulus evoked behaviors, where GABA B receptors are required for neural activity.…”