Figure 1.
Fly immobilized for modified PER assay.
The fly is placed into a truncated yellow tip. Tastant is presented to the fly with a piece of paper dipped in a sucrose solution.
Figure 2.
Effect of an odorant 4-methylphenol on PER.
Wild type flies without a) antenna (Ant −, MP+), b) no olfactory organs (Ant −, MP −) are tested. c) Antenna less flies (Ant −, MP+) of Or83b::Gal4, UAS::shibirets1 and the progeny from crossing these two lines (Or83b::Gal4×UAS::shibirets1) were tested with 1% sucrose. +/− indicates the presence/absence of 4-methylphenol (0.2% v/v) in the sucrose solution. For all figures: Error bars are S.E.M. n = 7 to 14. Paired stutdent's t-test were done on arcsin converted values. * : p<.05, ** : p<.01, *** : p<.001.
Figure 3.
Taste enhancement through the maxillary palp by various odors.
a) The effect of ethyl acetate (0.01%, mixed together in sucrose solution), Fenchone and 3-octanol (pure liquid deliver by a cotton swab) were tested. The sucrose concentration was 1% for all samples. The addition of these odors did not have a significant effect at other sucrose concentrations (data not shown). Ant −, MP+flies were used. b) Dose response relationship of taste enhancement in the maxillary palp with 4-methyphenol and c) ethyl acetate. Average PER from Ant −, MP+flies is plotted. The sucrose concentration was 1% for all samples. The X-axis is on a log scale. d) Effect of banana odor on taste. Overripe banana was used as odor source instead of pure chemicals. Ant −, MP+flies were used. n = 7 to 14
Figure 4.
Effect of HU treatment on taste enhancement. Flies were treated with HU at early larval stage.
a) Newly eclosed flies were collected before they can feed, and tested. b) Wild type Ant −, MP+flies were used. n = 7 to 14
Figure 5.
Introducing a foreign receptor in the maxillary palp.
Effect of methyl salicylate on taste enhancement in a) UAS::Or10a/+, b) Or83b::Gal4 /+ line and c) the offspring from the cross UAS::Or10a×Or83b::Gal4. The threshold for sucrose was different in the three lines. But the significant point was still at the sub-threshold concentration. Ant −, MP+flies were used in all experiments. n = 7 to 14
Figure 6.
Taste enhancement in a) D. simulans, b) D. pseudoobscura, c)Musca domestica, all without antenna (Ant −, MP +).
n = 7 to 14