Drosophila as a Model to Study the Mechanism of Nociception

Abstract

Nociception refers to the process of encoding and processing noxious stimuli, which allow animals to detect and avoid potentially harmful stimuli. Several types of stimuli can trigger nociceptive sensory transduction, including thermal, noxious chemicals, and harsh mechanical stimulation that depend on the corresponding nociceptors. In view of the high evolutionary conservation of the mechanisms that govern nociception from Drosophila melanogaster to mammals, investigation in the fruit fly Drosophila help us understand how the sensory nervous system works and what happen in nociception. Here, we present an overview of currently identified conserved genetics of nociception, the nociceptive sensory neurons responsible for detecting noxious stimuli, and various assays for evaluating different nociception. Finally, we cover development of anti-pain drug using fly model. These comparisons illustrate the value of using Drosophila as model for uncovering nociception mechanisms, which are essential for identifying new treatment goals and developing novel analgesics that are applicable to human health.

Keywords: Drosophila melanogaster; behavioral assay; conserved genetics; nociception; nociceptive sensory neurons.

FIGURE 1

Detection method of harmful temperature nociception in Drosophila. (A) When using a 46°C heat probe to contact Drosophila larvae, the rolling reaction time of wild-type larvae earlier than the larvae with impaired nociception. (B) Drosophila larvae with impaired nociception and wild-type larvae can cause rolling reaction when placed in water at 33–34 and 28–29°C respectively. (C) When using a cold probe to contact larvae, the rolling reaction time of wild-type larvae earlier than the larvae with impaired nociception. (D) After keeping the adult flies on a hot plate at 47°C, record the incubation period of the Drosophila to produce a jumping response. (E) Place the adult flies in a heating device, and wild-type flies will concentrate on the upper part of the device with a suitable temperature. (F) The optical drive heat avoidance test uses a heated aluminum ring as a harmful barrier between the adult Drosophila and the light source (attractive).

FIGURE 2

Detection method of chemical and mechanical nociception in Drosophila. (A) Use a pipette to place the chemical stimulus around the body of the larvae and record the incubation period. (B) Adult flies with impaired nociception eats indiscriminately, while wild-type flies eat only control food. (C) Provide two kinds of food and record the PER score of adult flies. (D) The von Frey fiber was calibrated and used for the determination of mechanical nociception: wild-type adult flies will have a rolling response when the force exceeds 45 mN, and the adult flies with impaired nociception have a greater rolling force.

FIGURE 3

Detection method of chronic pain perception in flies. (A) Drosophila larvae have a reduced nociceptive temperature threshold and overreact to noxious temperature stimuli after exposure to UV light. (B) After amputation, adult flies were subjected to thermal stimulation. Adult flies have increased thermal sensitivity to innocuous temperatures (allodynia).