Aedes aegyptigut transcriptomes respond differently to microbiome transplants from field-caught or laboratory-reared mosquitoes

Abstract

The mosquito microbiome is critical for host development and plays a major role in many aspects of mosquito biology. While the microbiome is commonly dominated by a small number of genera, there is considerable variation in composition among mosquito species, life stages, and geography. How the host controls and is affected by this variation is unclear. Using microbiome transplant experiments, we asked whether there were differences in transcriptional responses when mosquitoes of different species were used as microbiome donors. We used microbiomes from four different donor species spanning the phylogenetic breadth of the Culicidae, collected either from the laboratory or field. We found that when recipients received a microbiome from a donor reared in the laboratory, the response was remarkably similar regardless of donor species. However, when the donor had been collected from the field, far more genes were differentially expressed. We also found that while the transplant procedure did have some effect on the host transcriptome, this is likely to have had a limited effect on mosquito fitness. Overall, our results highlight the possibility that variation in mosquito microbiome communities are associated with variability in host-microbiome interactions and further demonstrate the utility of the microbiome transplantation technique.

Establishment and comparative genomics of a high-quality collection of mosquito-associated bacterial isolates - MosAIC (Mosquito-Associated Isolate Collection)

“…Using these approaches, we recently determined the ability of Cedecea neteri to form biofilms, showing this to be a key factor that contributes to colonisation of Aedes aegypti mosquitoes (39). We also found the transcriptome of transplant recipients responded similarly when receiving a microbiome from a laboratory-reared donor regardless of mosquito species, but showed more differentially expressed genes when the donor was field-caught (40).…”

A cryopreservation method to recover laboratory- and field-derived bacterial communities from mosquito larval habitats

“…We recently developed an approach to successfully isolate and transfer complete bacterial communities within and between adult mosquitoes of different donor and recipient species, including Aedes aegypti and Culex quinquefasciatus mosquitoes that serve as primary vectors of arboviral infections and filariasis in humans [13]. We then demonstrated the utility of this approach to study the factors shaping microbiota acquisition and assembly in mosquitoes and the mechanisms by which specific microbial taxa and assemblages contribute to different mosquito traits under controlled conditions [13,14]. However, while these results highlight the value of expanding tools to manipulate the microbiota in mosquitoes, important questions remain regarding (i) the utility of microbiota transplantation approaches to establish reproducible communities in mosquito larval rearing environments, which harbor bacterial communities that are much more complex than those in adult mosquitoes [15][16][17][18][19], and (ii) how microbiota transplantation efficacy may be shaped by long-term preservation of donor bacterial communities (e.g., via cryogenic freezing), which is absolutely necessary to facilitate longterm studies and intra-and interlaboratory comparisons but may introduce additional variability via impacts on bacterial viability and recovery [20][21][22][23][24][25].…”