Biology subjects

Staubach, F.

Publications and source records attributed to Staubach, F..

13 recordsLinked to original sources

bioRxiv2024

A diverse gut virome from Drosophila melanogaster

Drosophila melanogaster is not only one of the most important models of antiviral immunity in invertebrates, but is also a powerful model for research of the gut microbiome. Although recent studies have continued to improve our knowledge of the fly gut microbiota, the viral component of the microbiome has remained unexplored. Here we explore the viral component of the Drosophila melanogaster gut microbiome using deep metagenomic DNA sequencing. We recovered 3035 phage sequences, resulting in 167 viral Metagenome-Assembled Genomes. The majority of these sequences are potentially novel bacteriophages from the order Caudovirales, which mainly target major gut bacteria of D. melanogaster, including Lactobacillus, Acetobacter, and Gluconobacter. Our functional annotation and discovery of auxiliary metabolic genes showed that these bacteriophages have the potential to influence microbial metabolism and genetic information processing. We also identified evidence of known fly pathogens Drosophila Kallithea nudivirus, Vesanto bidna-like virus, and Viltain densovirus, some of which were common in our studied populations. Our findings reveal a complex and diverse phage community in the D. melanogaster gut microbiome, paving the way to study host-phage related research in the natural microbial communities.

microbiology↗

bioRxiv2023

Integrated spatial protein and RNA analysis on the same section using MICS technology

Spatial Biology has evolved from the molecular characterization of microdissected cells to high throughput spatial RNA and protein expression analysis at scale. The main limitation of spatial technologies so far is the inability to resolve protein and RNA information in the same histological section. Here, we report for the first time the integration of highly multiplexed RNA and protein detection on the same tissue section. We developed a new, automated, spatial RNA detection method (RNAsky), which is based on targeted rolling circle amplification and iterative staining. We combine RNAsky with MACSima Imaging Cyclic Staining (MICS) based protein analysis and show compatibility with subsequent standard hematoxylin and eosin (H&E) staining. Using both, open-source tools and our recently developed software suite MACS(R) iQ View, we demonstrate our multiomics MICS workflow by characterizing key immune-oncology markers at subcellular resolution across normal and diseased tissues.

molecular biology↗

bioRxiv2021

Drosophila Evolution over Space and Time (DEST) - A New Population Genomics Resource

Drosophila melanogaster is a leading model in population genetics and genomics, and a growing number of whole-genome datasets from natural populations of this species have been published over the last 20 years. A major challenge is the integration of these disparate datasets, often generated using different sequencing technologies and bioinformatic pipelines, which hampers our ability to address questions about the evolution and population structure of this species. Here we address these issues by developing a bioinformatics pipeline that maps pooled sequencing (Pool-Seq) reads from D. melanogaster to a hologenome consisting of fly and symbiont genomes and estimates allele frequencies using either a heuristic (PoolSNP) or a probabilistic variant caller (SNAPE-pooled). We use this pipeline to generate the largest data repository of genomic data available for D. melanogaster to date, encompassing 271 population samples from over 100 locations in >20 countries on four continents based on a combination of 121 unpublished and 150 previously published genomic datasets. Several of these locations have been sampled at different seasons across multiple years. This dataset, which we call Drosophila Evolution over Space and Time (DEST), is coupled with sampling and environmental meta-data. A web-based genome browser and web portal provide easy access to the SNP dataset. Our aim is to provide this scalable platform as a community resource which can be easily extended via future efforts for an even more extensive cosmopolitan dataset. Our resource will enable population geneticists to analyze spatio-temporal genetic patterns and evolutionary dynamics of D. melanogaster populations in unprecedented detail.

genomics↗

bioRxiv2020

The discovery, distribution and diversity of DNA viruses associated with Drosophila melanogaster in Europe

Drosophila melanogaster is an important model for antiviral immunity in arthropods, but very few DNA viruses have been described from the family Drosophilidae. This deficiency limits our opportunity to use natural host-pathogen combinations in experimental studies, and may bias our understanding of the Drosophila virome. Here we report fourteen DNA viruses detected in a metagenomic analysis of approximately 6500 pool-sequenced Drosophila, sampled from 47 European locations between 2014 and 2016. These include three new Nudiviruses, a new and divergent Entomopox virus, a virus related to Leptopilina boulardi filamentous virus, and a virus related to Musca domestica salivary gland hypertrophy virus. We also find an endogenous genomic copy of Galbut virus, a dsRNA Partitivirus, segregating at very low frequency. Remarkably, we find that Drosophila Vesanto virus, a small DNA virus previously described as a Bidnavirus, may be composed of up to 12 segments and represent a new lineage of segmented DNA viruses. Two of the DNA viruses, Drosophila Kallithea nudivirus and Drosophila Vesanto virus are relatively common, found in 2% or more of wild flies. The others are rare, with many likely to be represented by a single infected fly. We find that virus prevalence in Europe reflects the prevalence seen in publicly-available datasets, with Drosophila Kallithea nudivirus and Drosophila Vesanto virus the only ones commonly detectable in public data from wild-caught flies and large population cages, and the other viruses being rare or absent. These analyses suggest that DNA viruses are at lower prevalence than RNA viruses in D. melanogaster, and may be less likely to persist in laboratory cultures. Our findings go some way to redressing an earlier bias toward RNA virus studies in Drosophila, and lay the foundation needed to harness the power of Drosophila as a model system for the study of DNA viruses.

microbiology↗

bioRxiv2020

Horizontal gene transfer-mediated bacterial strain variation affects host fitness

How microbes affect host fitness and environmental adaptation has become a fundamental research question in evolutionary biology. We tested for associations of bacterial genomic variation and Drosophila melanogaster offspring number in a microbial Genome Wide Association Study (GWAS). Leveraging strain variation in the genus Gluconobacter, a genus of bacteria that are commonly associated with Drosophila under natural conditions, we pinpoint the thiamine biosynthesis pathway (TBP) as contributing to differences in fitness conferred to the fly host. By tracing the evolutionary history of TBP genes in Gluconobacter, we find that TBP genes were most likely lost and reacquired by horizontal gene transfer (HGT). We suggest that HGT might contribute to microbiome flexibility and speculate that it can also more generally contribute to host adaptation.

evolutionary biology↗

bioRxiv2020

Inference of recent admixture using genotype data

The inference of biogeographic ancestry (BGA) has become a focus of forensic genetics. Misinference of BGA can have profound unwanted consequences for investigations and society. We show that recent admixture can lead to misclassification and erroneous inference of ancestry proportions, using state of the art analysis tools with (i) simulations, (ii) 1000 genomes project data, and (iii) two individuals analyzed using the ForenSeq DNA Signature Prep Kit. Subsequently, we extend existing tools for estimation of individual ancestry (IA) by allowing for different IA in both parents, leading to estimates of parental individual ancestry (PIA), and a statistical test for recent admixture. Estimation of PIA outperforms IA in most scenarios of recent admixture. Furthermore, additional information about parental ancestry can be acquired with PIA that may guide casework. HighlightsO_LIWe improve statistical methods as used in STRUCTURE and ADMIXTURE for Biogeographical Ancestry (BGA) inference to account for recent admixture, i.e. different admixture of both parents. C_LIO_LIThe resulting recent admixture model has a higher accuracy in estimating individual admixture in most cases. C_LIO_LIWe give a likelihood ratio test for recent admixture, which is both highly specific and sensitive for recent admixture. C_LIO_LIWe find evidence of recent admixture in the 1000 genomes dataset. C_LIO_LIThe self-report on recent admixture of two self-sequenced samples was only confirmed in one case. C_LI

genetics↗

bioRxiv2019

No evidence for immune-gene specific signals of selection in termites

It has been hypothesized that selection pressure from pathogens plays an important role in shaping social evolution. Social behaviour, in particular brood care, is associated with pathogen pressure in wood-dwelling \"lower\" termites. Yet, generally pathogen pressure is low in wood-dwelling termite species that never leave the nest except for the mating flight. In comparison, pathogen pressure is higher in species that leave the nest to forage, and thus constantly encounter a diversity of microbes from their environment. We hypothesized that such differences in pathogen pressure are also reflected by differences in the intensity of natural selection on immune genes. We tested this hypothesis in a phylogenetic framework, analyzing rates of non-synonymous and synonymous substitutions on single-copy immune genes. Therefore, we leveraged recent genomic and transcriptomic data from eight termite species, representing wood-dwelling and foraging species as well as 14 additional species spanning the winged insects (Pterygota). Our results provide no evidence for a role of pathogen pressure in selection intensity on single-copy immune genes. Instead, we found evidence for a genome-wide pattern of relaxed selection in termites.\n\nLife Science Identifiers (as available Zoobank)Ephemera danica:\n\nurn:lsid:zoobank.org:act:06633F75-4809-4BB3-BDCB-6270795368D5\n\nCoptotermes sp.\n\nurn:lsid:zoobank.org:pub:D6724B7F-F27A-47DC-A4FC-12859ECA0C71\n\nBlattella germanica:\n\nrn:lsid:zoobank.org:pub:1EA126BA-E9D2-4AA6-8202-26BA5B09B8AD\n\nLocusta migratoria\n\nurn:lsid:zoobank.org:pub:D792A09E-844A-412A-BFCA-5293F8388F8C\n\nPeriplaneta americana (Blatta americana):\n\nurn:lsid:zoobank.org:act:95113A55-4C6D-4DC7-A0E5-620BACADFFE5\n\nApis mellifera:\n\nurn:lsid:zoobank.org:act:9082C709-6347-4768-A0DC-27DC44400CB2\n\nBombyx mori (Phalaena (Bombyx) mori)\n\nurn:lsid:zoobank.org:act:215466E3-E77F-46E9-8097-372837D7A375\n\nDrosophila melanogaster:\n\nurn:lsid:zoobank.org:act:5B39F0AA-270D-4AA8-B9A3-C36A3A265910

evolutionary biology↗

bioRxiv2019

Continent-wide structure of bacterial microbiomes of European Drosophila melanogaster suggests host-control

The relative importance of host-control, environmental effects, and stochasticity in the assemblage of host-associated microbiomes has been much debated. With recent sampling efforts, the underpinnings of D. melanogasters microbiome structure have become tractable on larger spatial scales. We analyzed the microbiome among fly populations that were sampled across Europe by the European Drosophila Population Genomics Consortium (DrosEU). We combined environmental data on climate and food-substrate, dense genomic data on host population structure, and microbiome profiling. Food-substrate, temperature, and host population-structure correlated with microbiome-structure. The microbes, whose abundance was co-structured with host populations, also differed in abundance between flies and their substrate in an independent survey, suggesting host-control. Patterns of enrichment and depletion of microbes between host and substrate were consistent with a model of host-control, where the host manipulates its microbiome for its benefit. Putative host-control was bacterial strain specific, supporting recent evidence for high specificity of D. melanogaster-microbe interaction.

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↗

bioRxiv2018

Genomic analysis of European Drosophila melanogaster populations on a dense spatial scale reveals longitudinal population structure and continent-wide selection

Genetic variation is the fuel of evolution, with standing genetic variation especially important for short-term evolution and local adaptation. To date, studies of spatio-temporal patterns of genetic variation in natural populations have been challenging, as comprehensive sampling is logistically difficult, and sequencing of entire populations costly. Here, we address these issues using a collaborative approach, sequencing 48 pooled population samples from 32 locations, and perform the first continent-wide genomic analysis of genetic variation in European Drosophila melanogaster. Our analyses uncover longitudinal population structure, provide evidence for continent-wide selective sweeps, identify candidate genes for local climate adaptation, and document clines in chromosomal inversion and transposable element frequencies. We also characterise variation among populations in the composition of the fly microbiome, and identify five new DNA viruses in our samples.

evolutionary biology↗

bioRxiv2017

Rapid seasonal evolution in innate immunity of wild Drosophila melanogaster

Understanding the rate of evolutionary change and the genetic architecture that facilitates rapid adaptation is a current challenge in evolutionary biology. Comparative studies show that genes with immune function are among the most rapidly evolving genes in a range of taxa. Here, we use immune defense in natural populations of D. melanogaster to understand the rate of evolution in natural populations and the genetics underlying the rapid change. We probed the immune system using the natural pathogens Enterococcus faecalis and Providencia rettgeri to measure post-infection survival and bacterial load of wild D. melanogaster populations collected across seasonal time along a latitudinal transect on the eastern North America (Massachusetts, Pennsylvania, and Virginia). There are pronounced and repeatable changes in the immune response over approximately 10 generations between the spring and fall populations with a significant but less distinct difference among geographic locations. Genes with known immune function are not enriched among alleles that cycle with seasonal time, but the immune function of a subset of seasonally cycling alleles in immune genes was tested using reconstructed outbred populations. We find that flies containing seasonal alleles in Thioester-containing protein 3 (Tep3) have different functional responses to infection and that epistatic interactions among seasonal Tep3 and Drosomycin-like 6 (Dro6) alleles produce the immune phenotypes observed in natural populations. This rapid, cyclic response to seasonal environmental pressure broadens our understanding of the complex ecological and genetic interactions determining the evolution of immune defense in natural populations.

evolutionary biology↗

bioRxiv2017

Individual Variation Of Natural D. melanogaster Associated Bacterial Communities

D. melanogaster has become an important model organism to study host-microbe interaction. However, we still know little about the natural microbial communities that are associated with D. melanogaster. Especially, information on inter-individual variation is still lacking because most studies so far have used pooled material from several flies. Here, we collected bacterial 16S rRNA gene community profiles from a set of 32 individuals from a single population and compare the variation to that of samples collected from different substrates and locations. While community differences were on average larger between samples collected from different substrates, there was still a surprising amount of variation of microbial communities between individual flies. The samples clustered into two groups suggesting that there are yet unknown factors that affect the composition of natural fly associated microbial communities and need research.\n\nImportanceD. melanogaster is an important model organism in evolutionary biology and also for the study of host-microbe interaction. In order to connect these to aspects of D. melanogaster biology, it is crucial to better understand the natural D. melanogaster microbiota because only the natural microbiota can affect the evolution of the host. We present, to our knowledge, the first data set that captures inter-individual variation of D. melanogaster associated bacterial communities. Clustering of communities into two larger groups suggests that there are important drivers of these communities that we do not understand yet suggesting in return that more research on the natural microbiota of D. melanogaster is needed.

microbiology↗

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↗