Gut microbiome modulates Drosophila aggression through octopamine signaling

Abstract

Gut microbiome profoundly affects many aspects of host physiology and behaviors. Here we report that gut microbiome modulates aggressive behaviors in Drosophila. We found that germ-free males showed substantial decrease in inter-male aggression, which could be rescued by microbial re-colonization. These germ-free males are not as competitive as wild-type males for mating with females, although they displayed regular levels of locomotor and courtship behaviors. We further found that Drosophila microbiome interacted with diet during a critical developmental period for the proper expression of octopamine and manifestation of aggression in adult males. These findings provide insights into how gut microbiome modulates specific host behaviors through interaction with diet during development.

Behavior Individuality: A Focus on Drosophila melanogaster

“…It is known that Wolbachia infection affects different D. melanogaster behaviors such as sleep (Bi et al, 2018 ), temperature preference (Truitt et al, 2019 ), or aggression (Rohrscheib et al, 2015 ). Alteration in the gut microbiome can affect aggression in Drosophila males (Jia et al, 2021 ) or sleep and memory (Silva et al, 2021 ). Those results point to the interaction of individuals with microorganisms as another potential source of interindividual behavior variability that must be taken into consideration.…”

Drosophila Model for Studying Gut Microbiota in Behaviors and Neurodegenerative Diseases

“…At least three studies have reported that the gut microbiota does not affect courtship behavior in Drosophila [33,35,51]; however, it should be noted that each study used different wild-type flies and employed different methods to generate germ-free flies. Contrary to these studies, Heys et al showed that the gut microbiota counteracts the male outbreeding strategy by altering the female sexual signaling, which leads to reduced sperm transfer from male flies [31].…”

Life History Traits in Two Drosophila Species Differently Affected by Microbiota Diversity under Lead Exposure

“…Drosophila gut microbiota in laboratory is represented by a low-diversity bacterial community [4,5], but it has great implications on its overall health. The gut microbiome of Drosophila contributes to a variety of host traits, such as innate immunity [6], lifespan [7][8][9], nutrition and reproduction [10] and behavior [11,12]. Shifts in microbiota could lead to serious consequences on host physiology, causing even mortality [13].…”