Biology subjects

Dedeine, F.

Publications and source records attributed to Dedeine, F..

3 recordsLinked to original sources

bioRxiv2020

Alteration of gut microbiota with rifampicin does not impair maternal care in the European earwig

AO_SCPLOWBSTRACTC_SCPLOWThe microbes residing within the gut of an animal host often increase their own fitness by modifying their hosts physiological, reproductive, and behavioural functions. Whereas recent studies suggest that they may also shape host sociality and therefore have critical effects on animal social evolution, the impact of the gut microbiota on maternal care remains unexplored. This is surprising, as this behaviour is widespread among animals, often determines the fitness of both juveniles and parents, and is essential in the evolution of complex animal societies. Here, we tested whether life-long alterations of the gut microbiota with rifampicin - a broad-spectrum antibiotic - impair pre- and post-hatching maternal care in the European earwig. Our results first confirm that rifampicin altered the mothers gut microbial communities and indicate that the composition of the gut microbiota differs before and after egg care. Contrary to our predictions, however, the rifampicin-induced alterations of the gut microbiota did not modify pre- or post-hatching care. Independent of maternal care, rifampicin increased the females feces production and resulted in lighter eggs and juveniles. By contrast, rifampicin altered none of the other 21 physiological, reproductive and longevity traits measured over the 300 days of a females lifetime. Overall, these findings reveal that altering the gut microbiota with a large spectrum antibiotic such as rifampicin does not necessarily affect host sociality. They also emphasize that not all animals have evolved a co-dependence with their microbiota and call for caution when generalizing the central role of gut microbes in host biology.

evolutionary biology↗

bioRxiv2019

Ecological specificity of the metagenome in a set of lower termite species supports contribution of the microbiome to adaptation of the host

BackgroundElucidating the interplay between hosts and their microbiomes in ecological adaptation has become a central theme in evolutionary biology. A textbook example of microbiome-mediated adaptation is the adaptation of lower termites to a wood-based diet, as they depend on their gut microbiome to digest wood. Lower termites have further adapted to different life types. Termites of the wood-dwelling life type never leave their nests and feed on a uniform diet. Termites of the foraging life type forage for food outside the nest and have access to other nutrients. Here we sought to investigate whether the microbiome that is involved in food substrate breakdown and nutrient acquisition might contribute to adaptation to these ecological differences. We reasoned that this should leave ecological imprints on the microbiome.\n\nResultsWe investigated the protist and bacterial microbiomes of a total of 29 replicate colonies from five termite species, covering both life types, using metagenomic shotgun sequencing. The microbiome of wood-dwelling species with a uniform wood diet was enriched for genes involved in lignocellulose degradation. Furthermore, metagenomic patterns suggest that the microbiome of wood-dwelling species relied primarily on direct fixation of atmospheric nitrogen, while the microbiome of foraging species entailed the necessary pathways to utilize nitrogen in the form of nitrate for example from soil.\n\nConclusionOur findings are consistent with the notion that the microbiome of wood-dwelling species bears an imprint of its specialization on degrading a uniform wood diet, while the microbiome of the foraging species might reflect its adaption to access growth limiting nutrients from more diverse sources. This supports the idea that specific subsets of functions encoded by the microbiome can contribute to host adaptation.

evolutionary biology↗

bioRxiv2016

Bacterial but not protist gut microbiota align with ecological specialization in a set of lower termite species

The role of microbes in adaptation of higher organisms to the environment is becoming increasingly evident, but remains poorly understood. Protist and bacterial microbes facilitate that lower termites thrive on wood and are directly involved in substrate break down. During the course of evolution lower termites adapted to different diets and lifestyles. In order to test whether there are changes of the termite gut microbiota that co-occur and hence could be related to diet and lifestyle adaptation, we assessed the bacterial and protist communities in a multispecies framework profiling three wood-dwelling and two foraging lower termite species using 16S and 18S rRNA gene amplicon sequencing. Termites were kept under controlled conditions on the same diet to minimize environmental effects on their gut microbiota. We found that protist communities group according to host phylogeny while bacterial communities group according to lifestyle. The change from the ancestral wood-dwelling to a foraging lifestyle coincides with exposure to more diverse and higher concentrations of pathogens as well as a more diverse diet. Accordingly, we identified bacteria that are associated with foraging termites of the genus Reticulitermes and could function as probiotics or be metabolically important on a more diverse diet. Furthermore, protist and bacterial diversity are correlated, suggesting not only that many termite gut bacteria are associated with protists, but also suggesting a role of protist diversity in the evolution of bacterial diversity in the termite gut or vice versa.

evolutionary biology↗