G-protein gamma subunit 1 is required for sugar reception in Drosophila.
Though G-proteins have been implicated in the primary step of taste signal transduction, no direct demonstration has been done in insects. We show here that a G-protein gamma subunit, Ggamma1, is required for the signal transduction of sugar taste reception in Drosophila. The Ggamma1 gene is expressed mainly in one of the gustatory receptor neurons. Behavioral responses of the flies to sucrose were reduced by the targeted suppression of neural functions of Ggamma1-expressing cells using neural modulator genes such as the modified Shaker K+ channel (EKO), the tetanus toxin light chain or the shibire (shi(ts1)) gene. RNA interference targeting to the Ggamma1 gene reduced the amount of Ggamma1 mRNA and suppressed electrophysiological response of the sugar receptor neuron. We also demonstrated that responses to sugars were lowered in Ggamma1 null mutant, Ggamma1(N159). These results are consistent with the hypothesis that Ggamma1 participates in the signal transduction of sugar taste reception.
Ishimoto
Hiroshi
H
Department of Biology, Graduate School of Sciences, Kyushu University, Ropponmatsu, Fukuoka, Japan.
Takahashi
Kuniaki
K
Ueda
Ryu
R
Tanimura
Teiichi
T
D000818:Animals; D001522:Behavior, Animal / Q000187:drug effects / Q000502:physiology; D029721:Drosophila Proteins / Q000235:genetics / Q000378:metabolism*; D004331:Drosophila melanogaster / Q000033:anatomy & histology / Q000187:drug effects* / Q000235:genetics / Q000378:metabolism*; D044388:GTP-Binding Protein gamma Subunits / Q000235:genetics / Q000378:metabolism*; D015870:Gene Expression; D006720:Homozygote; D009154:Mutation / Q000235:genetics; D009474:Neurons / Q000187:drug effects / Q000378:metabolism; D015221:Potassium Channels / Q000235:genetics / Q000378:metabolism; D034622:RNA Interference; D051637:Shaker Superfamily of Potassium Channels; D013395:Sucrose / Q000494:pharmacology*; D013649:Taste / Q000187:drug effects / Q000502:physiology*
D029721:Drosophila Proteins; D044388:GTP-Binding Protein gamma Subunits; C587156:Ggamma1 protein, Drosophila; D015221:Potassium Channels; C496929:Sh protein, Drosophila; D051637:Shaker Superfamily of Potassium Channels; D013395:Sucrose