Mutants in phospholipid signaling attenuate the behavioral response of adult Drosophila to trehalose.
In Drosophila melanogaster, gustatory receptor genes (Grs) encode putative G-protein-coupled receptors (GPCRs) that are expressed in gustatory receptor neurons (GRNs). One of the Gr genes, Gr5a, encodes a receptor for trehalose that is expressed in a subset of GRNs. Although a role for the G protein, Gsα, has been shown in Gr5a-expressing taste neurons, there is the residual responses to trehalose in Gsα mutants which could suggest additional transduction mechanisms. Expression and genetic analysis of the heterotrimeric G-protein subunit, Gq, shown here suggest involvement of this Gα subunit in trehalose perception in Drosophila. A green fluorescent protein reporter of Gq expression is detected in gustatory neurons in the labellum, tarsal segments, and wing margins. Animals heterozygous for dgq mutations and RNA interference-mediated knockdown of dgq showed reduced responses to trehalose in the proboscis extension reflex assay and feeding behavior assay. These defects were rescued by targeted expression of the wild-type dgqα transgene in the GRNs. These data together with observations from other mutants in phospholipid signaling provide insights into the mechanisms of taste transduction in Drosophila.
Kain
Pinky
P
National Centre for Biological Sciences, Tata Institute of Fundamental Research, Bellary Road, Bangalore 560065, India.
Badsha
Farhath
F
Hussain
Syed Mubarak
SM
Nair
Amit
A
Hasan
Gaiti
G
Rodrigues
Veronica
V
D000818:Animals; D001522:Behavior, Animal; D029721:Drosophila Proteins / Q000235:genetics* / Q000378:metabolism; D004331:Drosophila melanogaster / Q000187:drug effects / Q000235:genetics / Q000502:physiology*; D005260:Female; D043802:GTP-Binding Protein alpha Subunits, Gq-G11 / Q000235:genetics* / Q000378:metabolism; D006579:Heterozygote; D008297:Male; D009154:Mutation; D034622:RNA Interference; D011956:Receptors, Cell Surface / Q000235:genetics / Q000378:metabolism; D015398:Signal Transduction; D050052:TRPC Cation Channels / Q000235:genetics / Q000378:metabolism; D013649:Taste / Q000502:physiology; D014199:Trehalose / Q000494:pharmacology*
D029721:Drosophila Proteins; D011956:Receptors, Cell Surface; D050052:TRPC Cation Channels; C405956:gustatory receptor, Drosophila; D014199:Trehalose; D043802:GTP-Binding Protein alpha Subunits, Gq-G11