Fig. 4.
Function of pain and pyx in peripheral sensory tissues is key for negative geotaxis. (A) Expression of the dominant negative UAS-pyxFAP driven by pyx-Gal4 disrupted negative geotaxis in the climbing assay. Note that in the 3 genotypes each transgene was in homozygous state. *, significant difference from pyx-Gal4 based on ANOVA (α level = 0.05) and post hoc test of Games Howell (ANOVA). n = 10 trials in each group. (B) pyx-Gal4 did not drive mCD8::GFP reporter expression in the brain or thoracico-abdominal ganglion. CNS tissues were stained with the nc82 antibody to visualize neuropil (red) and anti-GFP antibody to visualize the reporter. (Scale bars, 100 μm.) (C) Expression of UAS-pyxFAP driven by Appl-Gal4 (a pan-neuronal Gal4 driver) had no effect on negative geotaxis. n = 9 trials in each group. (D) In the leg, nuclear DsRed expression driven by iav-Gal4 was only detected in femoral chordotonal organs. Inset shows a cluster of nuclei of chordotonal neurons. (E) iav-Gal4 did not drive mCD8::GFP expression in central neurons, but anti-GFP staining was present in projections of sensory afferents from Johnston's organ and leg chordotonal neurons (green). (Scale bars, 100 μm.) (F) Expression of UAS-pain under the control of iav-Gal4 restored negative geotaxis. *, significant difference from each of the 2 controls, based on ANOVA (α level = 0.05) and post hoc test of Games Howell. n = 39 trials for pain1; iav-Gal4/+, n = 35 trials for pain1; UAS-pain/+, and n = 39 trials for pain1; iav-Gal4/UAS-pain. Data are mean ± SEM.