Biology subjects

Troitsky, T.

Publications and source records attributed to Troitsky, T..

3 recordsLinked to original sources

bioRxiv2022

Maternal transmission gives way to social transmission during gut microbiota assembly in wild mice

The mammalian gut microbiota influences a wide array of phenotypes and is considered a key determinant of fitness, yet knowledge about the transmission routes by which gut microbes colonise hosts in natural populations remains limited. Here, we use an intensively studied wild population of wood mice (Apodemus sylvaticus) to examine how vertical (maternal) and horizontal (social) transmission routes influence gut microbiota composition throughout life. We identify independent signals of maternal transmission (sharing of taxa between a mother and her offspring) and social transmission (sharing of taxa predicted by the social network), whose relative magnitudes shift as hosts age. In early life, gut microbiota composition is predicted to a similar extent by both maternal and social relationships, but by adulthood the impact of maternal transmission becomes undetectable, leaving only a signal of social transmission. By exploring which taxa drive the maternal transmission signal, we further identify a candidate maternally-transmitted bacterial family in wood mice, the Lactobacillaceae. Overall, our findings suggest a shifting transmission landscape for wild mice, with a mothers influence on microbiota composition waning as offspring age, while the impact of social contacts remains strong and consistent.

microbiology↗

bioRxiv2021

Synchronous seasonality in the gut microbiota of wild wood mouse populations

O_LIThe gut microbiome performs many important functions in mammalian hosts, with community composition shaping its functional role. However, what factors drive individual microbiota variation in wild animals and to what extent these are predictable or idiosyncratic across populations remains poorly understood. C_LIO_LIHere, we use a multi-population dataset from a common rodent species (the wood mouse, Apodemus sylvaticus), to test whether a consistent set of core gut microbes is identifiable in this species, and to what extent the predictors of microbiota variation are consistent across populations. C_LIO_LIBetween 2014 and 2018 we used capture-mark-recapture and 16S rRNA profiling to intensively monitor two wild UK mouse populations and their gut microbiota, as well as characterising the microbiota from a laboratory-housed colony of the same species. C_LIO_LIAlthough broadly similar at high taxonomic levels and despite being only 50km apart, the two wild populations did not share a single bacterial amplicon sequence variant (ASV). Meanwhile, the laboratory-housed colony shared many ASVs with one of the wild populations from which it is thought to have been founded decades ago. Despite strong taxonomic divergence in the microbiota, the factors predicting compositional variation in each wild population were remarkably similar. We identified a strong and consistent pattern of seasonal microbiota restructuring that occurred at both sites, in all years, and within individual mice. While the microbiota was highly individualised, seasonal convergence in the gut microbiota among individuals occurred in late winter/early spring. C_LIO_LIThese findings reveal highly repeatable seasonal gut microbiota dynamics across distinct populations of this species, despite divergent taxa being involved. Providing a platform for future work to understand the drivers and functional implications of such predictable seasonal microbiome restructuring, including whether it might provide the host with adaptive seasonal phenotypic plasticity. C_LI

ecology↗

bioRxiv2020

Social networks strongly predict the gut microbiota of wild mice

The mammalian gut teems with beneficial microbes, yet how hosts acquire these symbionts remains poorly understood. Research in primates suggests that microbes can be picked up via social contact, but the role of social interactions in non-group-living species remains unexplored. Here, we use a passive tracking system to collect high resolution spatiotemporal activity data from wild mice (Apodemus sylvaticus). Social network analysis revealed social association strength to be the strongest predictor of microbiota similarity among individuals, controlling for factors including spatial proximity and kinship, which had far smaller or nonsignificant effects. This social effect was limited to interactions involving males (male-male and male-female), implicating sex-dependent behaviours as driving processes. Social network position also predicted microbiota richness, with well-connected hub individuals having the most diverse microbiotas. Overall, these findings suggest social contact provides a key transmission pathway for gut symbionts even in relatively asocial mammals, that strongly shapes the adult gut microbiota. This work underlines the potential for individuals to pick up beneficial symbionts as well as pathogens from social interactions.

ecology↗