A single pair of pharyngeal neurons functions as a commander to reject high salt in .

Salt (NaCl), is an essential nutrient for survival, while excessive salt can be detrimental. In the fruit fly, , internal taste organs in the pharynx are critical gatekeepers impacting the decision to accept or reject a food. Currently, our understanding of the mechanism through which pharyngeal gustatory receptor neurons (GRNs) sense high salt are rudimentary.

A single pair of pharyngeal neurons functions as a commander to reject high salt in .

Salt is an essential nutrient for survival, while excessive NaCl can be detrimental. In the fruit fly, , internal taste organs in the pharynx are critical gatekeepers impacting the decision to accept or reject a food. Currently, our understanding of the mechanism through which pharyngeal gustatory receptor neurons (GRNs) sense high salt are rudimentary.

Protocol for binary food choice assays using .

Food preference is a fundamental behavior for animals to choose nutritious foods while rejecting foods containing toxins. Here, we describe binary food choice assays using , which are straightforward approaches for the characterization of two-way choice tastants. We detail the preparation of flies and dye-containing food, followed by the binary-choice feeding assays and the determination of the preference index (PI).

TRPγ is required in neuroendocrine cells for post-ingestive food selection.

The mechanism through which the brain senses the metabolic state, enabling an animal to regulate food consumption, and discriminate between nutritional and non-nutritional foods is a fundamental question. Flies choose the sweeter non-nutritive sugar, L-glucose, over the nutritive D-glucose if they are not starved. However, under starvation conditions, they switch their preference to D-glucose, and this occurs independent of peripheral taste neurons.

Molecular and neuronal mechanisms for amino acid taste perception in the Drosophila labellum.

Amino acids are essential nutrients that act as building blocks for protein synthesis. Recent studies in Drosophila have demonstrated that glycine, phenylalanine, and threonine elicit attraction, whereas tryptophan elicits aversion at ecologically relevant concentrations. Here, we demonstrated that eight amino acids, including arginine, glycine, alanine, serine, phenylalanine, threonine, cysteine, and proline, differentially stimulate feeding behavior by activating sweet-sensing gustatory receptor neurons (GRNs) in L-type and S-type sensilla.

Ionotropic receptors mediate nitrogenous waste avoidance in Drosophila melanogaster.

Ammonia and its amine-containing derivatives are widely found in natural decomposition byproducts. Here, we conducted biased chemoreceptor screening to investigate the mechanisms by which different concentrations of ammonium salt, urea, and putrescine in rotten fruits affect feeding and oviposition behavior. We identified three ionotropic receptors, including the two broadly required IR25a and IR76b receptors, as well as the narrowly tuned IR51b receptor.

Cucurbitacin B Suppresses Hyperglycemia Associated with a High Sugar Diet and Promotes Sleep in .

Secondary metabolites enable plants to protect themselves from herbivorous insects. Among these, cucurbitacin B (cuc-B) is a bitter-tasting compound with promising pharmacological potential. Dietary exposure to cuc-B lowered the hemolymph glucose levels of fed with a high carbohydrate diet, which is homologous to high blood glucose in humans, and its effect was comparable to that of metformin, a well-known glucose-lowering drug.

Cucurbitacin B Activates Bitter-Sensing Gustatory Receptor Neurons via Gustatory Receptor 33a in .

The Gustatory system enables animals to detect toxic bitter chemicals, which is critical for insects to survive food induced toxicity. Cucurbitacin is widely present in plants such as cucumber and gourds that acts as an anti-herbivore chemical and an insecticide. Cucurbitacin has a harmful effect on insect larvae as well.

Transient Receptor Potential Channels and Metabolism.

Transient receptor potential (TRP) channels are nonselective cationic channels, conserved among flies to humans. Most TRP channels have well known functions in chemosensation, thermosensation, and mechanosensation. In addition to being sensing environmental changes, many TRP channels are also internal sensors that help maintain homeostasis.