tracking-sugar-elicited-local-searching-behavior-in-drosophila

Tracking Sugar-Elicited Local Searching Behavior in <i>Drosophila</i>

Foraging behavior is essential for the survival of organisms as it enables them to locate and acquire essential food resources. In Drosophila, hunger ...

Nagoya University

Mechanosensation provides animals with important sensory information in addition to olfaction and gustation during feeding behavior. Here, we used  larvae to investigate the role of softness sensing in behavior and learning. In the natural environment, larvae need to dig into soft foods for feeding. Finding foods that are soft enough to dig into is likely to be essential for their survival. We report that larvae can discriminate between different agar concentrations and prefer softer agar. Interestingly, we show that larvae on a harder surface search for a softer surface using memory associated with an odor, and that they evaluate foods by balancing softness and sweetness. These findings suggest that larvae integrate mechanosensory information with chemosensory input while foraging. Moreover, we found that the larval preference for softness is affected by genetic background.

Softness sensing and learning in  larvae.

Animals need to detect in the food essential amino acids that they cannot synthesize. We found that the odorant binding protein OBP19b, which is highly expressed in  taste sensilla, is necessary for the detection of several amino acids including the essential l-phenylalanine. The recombinant OBP19b protein was produced and characterized for its binding properties: it stereoselectively binds to several amino acids. Using a feeding-choice assay, we found that OBP19b is necessary for detecting l-phenylalanine and l-glutamine, but not l-alanine or D-phenylalanine. We mapped the cells expressing OBP19b and compared the electrophysiological responses of a single taste sensillum to several amino acids: OBP19b mutant flies showed a reduced response compared to control flies when tested to preferred amino acids, but not to the other ones. OBP19b is well conserved in phylogenetically distant species suggesting that this protein is necessary for detection of specific amino acids in insects.

A conserved odorant binding protein is required for essential amino acid detection in Drosophila.

In  , wing epidermal cells undergo programmed cell death as the last step of metamorphosis. The aim of this study was to evaluate the role of  , particularly the  mutation (  ), an allele of  , in the cell death. The wing epithelial cell death is suppressed by loss-of-function mutation of  , indicating that the death is governed by a cascade involving  . Examination of the cell death in  showed that precocious death started at G stage, 3 h before eclosion. Thus, mutated-HID in the  mutant was activated at G stage, supporting the gain-of-function effect of  mutation.

Teiichi Tanimura

Neural Circuit Group,
Division of Biological Science,
Graduate School of Science,
Neural Circuit Group, Division of Biological Science, Graduate School of Science

Nagoya University

Tracking Sugar-Elicited Local Searching Behavior in Drosophila

Teiichi Tanimura

Neural Circuit Group,Division of Biological Science,Graduate School of Science,Neural Circuit Group, Division of Biological Science, Graduate School of Science

Nagoya University

Tracking Sugar-Elicited Local Searching Behavior in Drosophila

Neural Circuit Group,
Division of Biological Science,
Graduate School of Science,
Neural Circuit Group, Division of Biological Science, Graduate School of Science