FIGURE 3.

Gut bacteria regulate the motor function and lifespan of female FL-HD Drosophila. (A) Newly eclosed FL-HD flies or controls expressing full length HTT with 25Qs (WT-HTT) were treated with penicillin-streptomycin (ABX) for 15 days to eliminate gut bacteria. A climbing assay was performed at days 1, 5, 10, and 15 post-treatment. The data are graphed as mean ± SEM, two-way ANOVA with Tukey’s multiple-comparisons test. ***p < 0.001, n = 9 groups of 10 flies. (B) Bacteria-deficient adult FL-HD flies were fed different strains of E. coli, A. senegalensis, and L. rhamnosus for 15 days. Locomotive behavior for each condition was quantified as in part (A). The data are reported as mean ± SEM, two-way ANOVA with Tukey’s multiple-comparisons test. ***p < 0.001; **p < 0.01, n = 6 groups of 10 flies. Part (C) shows the survival curve for FL-HD flies treated with two E. coli strains. The percent of flies that survived over time was calculated at different time points. The data are represented as mean ± SEM, two-way ANOVA with Tukey’s multiple-comparisons test. ***p < 0.001; **p < 0.01; *p < 0.05, n = 6 groups of 10 flies. (D) Immunostaining of the GI tract of control or E. coli (curli) treated FL-HD flies demonstrating bacterial colonization of fly gut. A monoclonal antibody generated to E. coli was used for detection. DAPI was used to stain the nuclei.