scholarly journals GxGxE interactions and adaptive potential of the microbiome in Drosophila melanogaster

2020 ◽  
Author(s):  
Lucas P. Henry ◽  
Michael Fernandez ◽  
Julien F. Ayroles

AbstractThe microbiome may serve as a reservoir of adaptive potential if hosts can leverage microbial adaptations in stressful environments. However, the facilitation of rapid host adaptation may be limited by interactions between host genotype, microbiome, and environment (GH x GM x E). Here, to understand how host x microbiome x environment interactions shape adaptation, we leverage >150 generations of experimental evolution in Drosophila melanogaster in a stressful environment, high sugar (HS) diet. The microbiome of HS adapted flies shifted to be dominated by one bacteria, Acetobacter pasteurianus. We next performed a fully reciprocal transplant experiment using the dominant control and HS bacteria to measure life-history and metabolic traits in flies. Mismatches between fly evolution and microbiome exerted fitness costs by slowing development and reducing fecundity, especially in the stressful HS diet. The GH x GM x E interactions observed suggest that both ecological context and host evolution shape the adaptive potential of the microbiome. We conclude by proposing future directions that highlight the benefit of using experimental evolution to study the contribution of the microbiome to host evolution.

Author(s):  
Lucas P Henry ◽  
Julien F Ayroles

Experimental evolution has a long history of uncovering fundamental insights into evolutionary processes but has largely neglected one underappreciated component--the microbiome. As eukaryotic hosts evolve, the microbiome may also evolve in response. However, the microbial contribution to host evolution remains poorly understood. Here, we analyzed the metagenomes from 10 E&R experiments in Drosophila melanogaster to determine how the microbiome changes in response to host selection. Bacterial diversity was significantly different in 5/10 studies in traits associated with metabolism or immunity. Additionally, we find that excluding reads from a facultative symbiont, Wolbachia, in the analysis of bacterial diversity changes the inference, raising important questions for future E&R experiments in D. melanogaster. Our results suggest the microbiome often responds to host selection but highlights the need for more work to understand how the microbiome changes the host response to selection.


2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Lucas P. Henry ◽  
Julien F. Ayroles

Abstract Background Experimental evolution has a long history of uncovering fundamental insights into evolutionary processes, but has largely neglected one underappreciated component--the microbiome. As eukaryotic hosts evolve, the microbiome may also respond to selection. However, the microbial contribution to host evolution remains poorly understood. Here, we re-analyzed genomic data to characterize the metagenomes from ten Evolve and Resequence (E&R) experiments in Drosophila melanogaster to determine how the microbiome changed in response to host selection. Results Bacterial diversity was significantly different in 5/10 studies, primarily in traits associated with metabolism or immunity. Duration of selection did not significantly influence bacterial diversity, highlighting the importance of associations with specific host traits. Conclusions Our genomic re-analysis suggests the microbiome often responds to host selection; thus, the microbiome may contribute to the response of Drosophila in E&R experiments. We outline important considerations for incorporating the microbiome into E&R experiments. The E&R approach may provide critical insights into host-microbiome interactions and fundamental insight into the genomic basis of adaptation.


Climate ◽  
2021 ◽  
Vol 9 (2) ◽  
pp. 36
Author(s):  
Kelly L. Bennett ◽  
William Owen McMillan ◽  
Jose R. Loaiza

Ae. (Stegomyia) aegypti L. and Aedes (Stegomyia) albopictus Skuse mosquitoes are major arboviral disease vectors in human populations. Interspecific competition between these species shapes their distribution and hence the incidence of disease. While Ae. albopictus is considered a superior competitor for ecological resources and displaces its contender Ae. aegypti from most environments, the latter is able to persist with Ae. albopictus under particular environmental conditions, suggesting species occurrence cannot be explained by resource competition alone. The environment is an important determinant of species displacement or coexistence, although the factors underpinning its role remain little understood. In addition, it has been found that Ae. aegypti can be adapted to the environment across a local scale. Based on data from the Neotropical country of Panama, we present the hypothesis that local adaptation to the environment is critical in determining the persistence of Ae. aegypti in the face of its direct competitor Ae. albopictus. We show that although Ae. albopictus has displaced Ae. aegypti in some areas of Panama, both species coexist across many areas, including regions where Ae. aegypti appear to be locally adapted to dry climate conditions and less vegetated environments. Based on these findings, we describe a reciprocal transplant experiment to test our hypothesis, with findings expected to provide fundamental insights into the role of environmental variation in shaping the landscape of emerging arboviral disease.


2021 ◽  
Author(s):  
Mark Phillips ◽  
Kenneth R. Arnold ◽  
Zer Vue ◽  
Heather Beasley ◽  
Edgar Garza Lopez ◽  
...  

Experimental evolution with Drosophila melanogaster has been used extensively for decades to study aging and longevity. In recent years, the addition of DNA and RNA sequencing to this framework has allowed researchers to leverage the statistical power inherent to experimental evolution study the genetic basis of longevity itself. Here we incorporated metabolomic data into to this framework to generate even deeper insights into the physiological and genetic mechanisms underlying longevity differences in three groups of experimentally evolved D. melanogaster populations with different aging and longevity patterns. Our metabolomic analysis found that aging alters mitochondrial metabolism through increased consumption of NAD+ and increased usage of the TCA cycle. Combining our genomic and metabolomic data produced a list of biologically relevant candidate genes. Among these candidates, we found significant enrichment for genes and pathways associated with neurological development and function, and carbohydrate metabolism. While we do not explicitly find enrichment for aging canonical genes, neurological dysregulation and carbohydrate metabolism are both known to be associated with accelerated aging and reduced longevity. Taken together, our results in total provide very plausible genetic mechanisms for what might be driving longevity differences in this experimental system. More broadly, our findings demonstrate the value of combining multiple types of omic data with experimental evolution when attempting to dissect mechanisms underlying complex and highly polygenic traits like aging.


2020 ◽  
Author(s):  
Eva L. Koch ◽  
Sonja H. Sbilordo ◽  
Frédéric Guillaume

AbstractIn presence of rapid environmental changes, it is of particular importance to assess the adaptive potential of populations, which is mostly determined by the additive genetic variation (VA) in fitness. In this study we used Tribolium castaneum (red flour beetles) to investigate its adaptive potential in three new environmental conditions (Dry, Hot, Hot-Dry). We tested for potential constraints that might limit adaptation, including negative genetic covariance between female and male fitness. Based on VA estimates for fitness, we expected the highest relative fitness increase in the most stressful condition Hot-Dry and similar increases in single stress conditions Dry and Hot. High adaptive potential in females in Hot was reduced by a negative covariance with male fitness. We tested adaptation to the three conditions after 20 generations of experimental evolution and found that observed adaptation mainly matched our predictions. Given that body size is commonly used as a proxy for fitness, we also tested how this trait and its genetic variance (including non-additive genetic variance) were impacted by environmental stress. In both traits, variances were sex and condition dependent, but they differed in their variance composition, cross-sex and cross-environment genetic covariances, as well as in the environmental impact on VA.


2015 ◽  
Vol 186 (5) ◽  
pp. 582-593 ◽  
Author(s):  
Vanessa Kellermann ◽  
Ary A. Hoffmann ◽  
Torsten Nygaard Kristensen ◽  
Neda Nasiri Moghadam ◽  
Volker Loeschcke

Botany ◽  
2010 ◽  
Vol 88 (10) ◽  
pp. 930-936 ◽  
Author(s):  
Laura L. Beaton ◽  
Susan A. Dudley

Previous studies have demonstrated that plants collected as seeds from roadside populations of Dipsacus fullonum L. subsp sylvestris (Huds.) Claphamare more tolerant of high salinity, low osmotic potentials, and hypoxia during juvenile growth stages than those from oldfield populations. However, it is unclear how tolerance to these abiotic stressors translates into performance in the roadside environment. Here, we conducted a reciprocal transplant experiment between oldfield and roadside environments. Seeds from three roadside and three oldfield populations were planted into oldfield and roadside sites in late fall. Throughout the spring and summer, the survivorship and size of the seedlings were monitored to examine differences in performance in the two habitats. We also assessed the relation between performance in the field and previous in vitro measures of salt and drought tolerance of each population. A drought caused high mortality levels in the oldfield and roadside. Individuals from roadside populations did not exhibit increased growth or survivorship in the roadside environment. In the early months of seedling growth, neither salt nor drought tolerance were significantly correlated with performance in the roadside during seedling establishment. Rather, during these early months, the average size of individuals in each population in the field was positively correlated with the population’s average seed mass, indicating that maternal provisioning had a greater impact than tolerance to particular environmental stresses during the juvenile stages of development. However, later in the summer, after the drought began, the average size of individuals from each population in the field was positively correlated with that population’s average drought tolerance.


Oecologia ◽  
2009 ◽  
Vol 161 (4) ◽  
pp. 781-790 ◽  
Author(s):  
Susanne Wölfle ◽  
Monika Trienens ◽  
Marko Rohlfs

1989 ◽  
Vol 67 (12) ◽  
pp. 3618-3624 ◽  
Author(s):  
Susan R. Smythe ◽  
Ian Hutchinson

Four populations of Carex lyngbyei from each of three estuaries with contrasting salinity regimes in northwestern North America (deltas of the Nanaimo, Skagit, and Squamish rivers) were grown in a reciprocal transplant experiment to determine the degree to which morphological differences were genetic or environmentally based. Shoot height, biomass per shoot, and aboveground biomass differences were generally not maintained in the transplant environment, suggesting that genetic control on morphological variation was weak. Transplant site salinity regimes had little effect on shoot density or survival. It is suggested that broadly adapted genotypes, capable of this sort of plastic response, may have a competitive advantage in these fluctuating estuarine environments. Key words: Carex lyngbyei, Pacific Northwest, plasticity, reciprocal transplants.


Sign in / Sign up

Export Citation Format

Share Document