Gr64eMB03533 mutants exhibit a statistically significant reduction in the response to trehalose, melezitose, m-glucoside and glucose. However, responses to sucrose, maltose, maltotriose, fructose and glycerol are unaffected.
Gr64eMB03533 mutants show a marked loss of preference for 30% beer against 5mM (as in wild-type).
Gr64eMB03533 flies show a substantially reduced preference for yeast extract and fermented grape. The preference for ripe banana is indistinguishable from wild-type flies.
Gr64eMB03533 mutant flies show virtually no response to 10% glycerol, whereas control flies show a strong response.
Gr64eMB03533 flies have a responsive sugar neuron, as a stimulus of 100mM sucrose elicits a firing rate comparable to that in control flies.
L-type sensilla in Gr64eMB03533 flies lack a response to 10% glycerol. In contrast, mean responses to sucrose, fructose and glucose are as in wild-type.
Gr64eMB03533 flies show greatly reduced proboscis extension responses to glycerol. In feeding preference assays in which populations of flies are presented with 5mM sucrose against varying concentrations of glycerol, wild-type flies show strong preferences for 1% and 10% glycerol.
Gr64eMB03533 is rescued by Gr64eUAS.cWa/Scer\GAL4Gr5a.8.5
Expression of Gr64eScer\UAS.cWa in sugar taste neurons (under the control of Scer\GAL4Gr5a.8.5) restores glycerol sensitivity, although only partial rescue is seen at a 1% glycerol concentration.