Abstract
Feeding decisions are highly plastic and bidirectionally regulated by neurons that either promote or inhibit feeding. In Drosophila melanogaster, recent studies have identified four GABAergic interneurons that act as critical brakes to prevent incessant feeding. These GABAergic neurons may inhibit target neurons that drive consumption. Here, we tested this hypothesis by examining GABA receptors and neurons that promote consumption. We find that Resistance to dieldrin (RDL), a GABAA type receptor, is required for proper control of ingestion. Knockdown of Rdl in a subset of neurons causes overconsumption of tastants. Acute activation of these neurons is sufficient to drive consumption of appetitive substances and non-appetitive substances and acute silencing of these neurons decreases consumption. Taken together, these studies identify GABAA receptor-expressing neurons that promote Drosophila ingestive behavior and provide insight into feeding regulation.
Highlights
The ability to adjust feeding behaviors in different environments and contexts is essential for an animal to survive
The fruit fly, Drosophila melanogaster, is an excellent model system to examine the neural circuits underlying the regulation of feeding behaviors; the fly brain contains a million fold fewer neurons compared to the human brain[2] and powerful genetic tools enable the manipulation of specific neurons
There are five GABAergic receptors in Drosophila: a heteromultimeric cationic channel composed of the subunits GABA and glycine-like receptor of Drosophila (GRD) and ligand-gated chloride channel homolog 3 (LCCH3) [18]; a GABAA type receptor (RDL) [19]; and 3 GABAB receptors (GABAB R1, GABAB R2, GABAB R3) [20]
Summary
The ability to adjust feeding behaviors in different environments and contexts is essential for an animal to survive. Homeostatic mechanisms that regulate food intake balance caloric consumption with energy expenditure, which influences the health, fitness, and body weight of an organism [1]. The fruit fly, Drosophila melanogaster, is an excellent model system to examine the neural circuits underlying the regulation of feeding behaviors; the fly brain contains a million fold fewer neurons compared to the human brain[2] and powerful genetic tools enable the manipulation of specific neurons. These features make the fly brain a tractable system for uncovering the neural circuitry for feeding regulation. The circuit principles uncovered in Drosophila may be shared throughout the animal kingdom
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
