262V Poster - 02. Immunity and the microbiome
Wednesday April 06, 4:00 PM - 7:00 PM

Authors:
Tanner B. Call ¹; Paige E. Bonnette ²; John M. Chaston ³; Shaleen B. Korch ⁴; Gerald B. Call ⁴

Affiliations:
1) Arizona College of Osteopathic Medicine, Midwestern University, Glendale, AZ; 2) Biomedical Sciences Program, College of Graduate Studies, Midwestern University, Glendale, AZ; 3) Department of Plant and Wildlife Sciences, College of Life Sciences, Brigham Young University, Provo, UT; 4) Department of Pharmacology, College of Graduate Studies, Midwestern University, Glendale, AZ

Keywords:
m. microbiome; l. locomotion/flight

It is known that the microbiota can affect motor function in Drosophila melanogaster. We undertook an experiment to test the effects of different bacterial mono- and combination-associations in w¹¹¹⁸ in our novel climbing assay. This assay uses the TriKinetics Multibeam Monitor to record the location of 16 individual flies every second over a 20-minute period. Analysis of the data can reveal multiple climbing and motor parameters. Using the standard bleaching protocol, w¹¹¹⁸ embryos were made axenic (germ-free) and were then mono-associated with Acetobacter pomorum, Acetobacter tropicalis, Lactobacillus brevis, or Lactiplantibacillus plantarum. Another group of w¹¹¹⁸ flies were associated with a combination of all four bacteria (Combo). Interestingly, the Combo group had the most significant effects on climbing metrics compared to the axenic control group, including increases in average height climbed, number of climbs, and total height climbed, which were unchanged by any of the mono-associations. The amount of time spent by the flies in the lower tube portion was decreased in both the Combo and A. tropicalis groups. These two groups also had an increased amount of time spent in the upper tube portion, suggesting that A. tropicalis increases the ability and or motivation of the flies to climb to the top of the tube and stay there longer. Both of the Acetobacter mono-associations and the Combo group had increased total movements and passes through the middle of the tube, indicating that the Acetobacter mono-associations promote increased locomotion in general. Interestingly, the L. brevis and L. plantarum mono-associations had no effects on climbing. This detailed analysis of climbing behavior in this study reveals some interesting findings. First off, the combination of all four bacteria had the most effects on climbing, indicating that the mixed microbiota in conventional flies likely promotes substantial influences on climbing. This finding shows that the host climbing phenotype is determined by community interactions in the microbiota and not by one or more community members acting individually. Second, the Acetobacter species appeared to be the most significant contributors to the effects observed with the Combo group, while the Lactobacillus species had no effects on climbing.