Pharyngeal stimulation with sugar triggers local searching behavior in Drosophila

J Exp Biol. 2017 Sep 15;220(Pt 18):3231-3237. doi: 10.1242/jeb.161646. Epub 2017 Jul 6.


Foraging behavior is essential for all organisms to find food containing nutritional chemicals. A hungry Drosophila melanogaster fly performs local searching behavior after drinking a small amount of sugar solution. Using video tracking, we examined how the searching behavior is regulated in D. melanogaster We found that a small amount of highly concentrated sugar solution induced a long-lasting searching behavior. After the intake of sugar solution, a fly moved around in circles and repeatedly returned to the position where the sugar droplet had been placed. The non-nutritious sugar d-arabinose, but not the non-sweet nutritious sugar d-sorbitol, was effective in inducing the behavior, indicating that sweet sensation is essential. Furthermore, pox-neuro mutant flies, which have no external taste bristles, showed local searching behavior, suggesting the involvement of the pharyngeal taste organ. Experimental activation of pharyngeal sugar-sensitive gustatory receptor neurons by capsaicin using the GAL4/UAS system induced local searching behavior. In contrast, inhibition of pharyngeal sugar-responsive gustatory receptor neurons abolished the searching behavior. Together, our results indicate that, in Drosophila, the pharyngeal taste-receptor neurons trigger searching behavior immediately after ingestion.

Keywords: Dance; Feeding; Fly; Gustation.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Appetitive Behavior
  • Arabinose / metabolism*
  • Drosophila melanogaster / physiology*
  • Feeding Behavior
  • Glucose / metabolism*
  • Male
  • Sensilla / physiology*
  • Taste Perception / physiology*


  • Arabinose
  • Glucose