Variation in the response to exercise stimulation in Drosophila: marathon runner versus sprinter genotypes

Abstract

Animals’ behaviors vary in response to their environment, both biotic and abiotic. These behavioral responses have significant impacts on animal survival and fitness, and thus, many behavioral responses are at least partially under genetic control. In Drosophila for example, genes impacting aggression, courtship behavior, circadian rhythms, and sleep have been identified. Animal activity also is influenced strongly by genetics. My lab previously has used the Drosophila melanogaster Genetics Reference Panel (DGRP) to investigate activity levels and identified over 100 genes linked to activity. Here, I re-examine these data to determine if Drosophila strains differ in their response to rotational exercise stimulation, not simply in the amount of activity, but in activity patterns and timing of activity. Specifically, I asked if there are fly strains exhibiting either a “marathoner” pattern of activity, i.e. remaining active throughout the two-hour exercise period, or a “sprinter” pattern, i.e. carrying out most of the activity early in the exercise period. The DGRP strains examined differ significantly in how much activity is carried out at the beginning of the exercise period, and this pattern is influenced by both sex and genotype. Interestingly, there is no clear link between the activity response pattern and lifespan of the animals. Using GWASs, I identify ten high confidence candidate genes that control to which degree Drosophila exercise behaviors fit a marathoner or sprinter activity pattern. This finding suggests that, similar to other aspects of locomotor behavior, timing of activity patterns in response to exercise stimulation is under genetic control.