Modulation of feeding behavior and peripheral taste response by aversive molecules in Drosophila melanogaster
Year: 2010
Type: dissertation
Abstract: In Drosophila melanogaster, taste involves hair-like structures called sensilla. At the tip of the sensilla, a pore allows the entry of the molecules in the hair shaft containing the dendrites of the chemosensory neurons. Each sensillum houses one mechanoreceptor neuron and two to four chemosensory neurons which are classified according to the taste quality they respond to. In this work, we have focused on the S cell, sensitive to sugars, and the L2 cell, which detects aversive molecules in many sensilla. We have developed a behavioral assay to measure feeding preferences in D. melanogaster. This assay, called MultiCAFE (MULTIple CApillary Feeder), quantitatively measures the consumption of solutions provided to groups of flies in several glass capillary tubes. This test allowed us to rank various alkaloids according to their antifeedant potency. We have studied the perception of these alkaloids in the taste sensilla of the proboscis, using extracellular electrophysiological recordings. Deterrent compounds have two modes of action on the taste sensilla: they activate the L2 cell but also inhibit the S cell if they are presented in mixture with sugars. We highlighted the specificity of this sugar detection inhibition. The mechanisms underlying this phenomenon are still unknown. We tested the hypothesis of a lateral interaction between the L2 and the S cell. We showed that the decrease in sucrose detection by the sugar-sensing cell in presence of strychnine is not due to a lateral inhibition caused by the bitter-sensing neuron.
Source: HAL
Author: Marie-Jeanne Sellier
Language: English
Subfield: Cellular and Molecular Neuroscience
Field: Neuroscience
Domain: Life Sciences
Open Access status: green
OpenAlex ID: W1170245253