Biology subjects

Reuss, F.

Publications and source records attributed to Reuss, F..

7 recordsLinked to original sources

bioRxiv2026

Insecticide resistance of Culex pipiens f. pipiens is geographically widespread in Germany and displays an unmatched genotypic and phenotypic resistance state

In Germany, insecticide use is recommended during mosquito-borne disease outbreaks, yet nationwide data on insecticide resistance in key vector species are scarce. This is particularly relevant for Culex pipiens s.l., a vector of West Nile virus. Here, we provide the first broad-scale assessment of molecular insecticide resistance (kdr and ace-1 mutations) in Cx. pipiens f. pipiens across Germany. We associated insecticide resistances with environmental conditions, potential links with mitochondrial variation of the cytochrome c oxidase I (COI) gene as well as phenotypic resistance (CDC bottle assay with permethrin) of the Frankfurt population with elevated kdr frequencies. Kdr resistance alleles were detected in German Cx. pipiens f. pipiens reaching frequencies of up to 50% in the metropolitan areas of Berlin and Frankfurt am Main. Annual precipitation was negatively associated with kdr allele frequency. Interestingly, ace-1 resistance mutations were only present in the metropolitan area of Frankfurt am Main and in Muggensturm (Rhine valley, southwestern Germany). COI haplotype analyses revealed low genetic variability within German Cx. pipiens f. pipiens populations with no association to the insecticide resistance genotype. Phenotypic assays of the Frankfurt population showed early signs of permethrin resistance, but unmatched genotypic and phenotypic resistance state. This study provides the first broad-scale assessment of molecular insecticide resistance in Cx. pipiens f. pipiens across Germany, establishing a baseline for resistance surveillance and vector control. Further research is needed to identify factors shaping phenotypic resistance, as molecular markers alone may not reliably predict resistance. Since sampling was restricted to urban green spaces, broader sampling across environmental gradients is needed to identify additional environmental effectors.

molecular biology↗

bioRxiv2026

Standing Genomic Variation inferred by popGWAS Predicts Seedling Drought Survival Experiment in Fagus sylvatica

Intensifying drought regimes across Central Europe, driven by global climate change, pose an increasing threat to forest regeneration, with the seedling stage representing the primary demographic bottleneck for long-lived tree species such as Fagus sylvatica. While intraspecific phenotypic variation in drought resistance among beech seedlings has been documented, the genomic basis of this variation remains poorly understood. Existing provenance trial approaches capture broad-sense heritability but lack the resolution to identify specific causal loci. To address this gap, we conducted a controlled soil drought experiment with Fagus sylvatica seedlings and applied a population-level genome-wide association study (GWAS), and leveraged individual survival length as a direct fitness proxy. We detected substantial variation in survival duration (10-40 days) among populations, with corresponding allele frequency differences at candidate loci whose functional annotations partially reflect known responses to environmental stress. Notably, seedlings sourced from an official seed bank consistently underperformed relative to wild-collected material, suggesting that current seed sourcing practices may inadvertently deplete adaptive genetic diversity. Our results demonstrate that standing genomic variation in natural Fagus sylvatica populations predicts differential seedling drought survival, and that the species retains substantial genetic potential to cope with prolonged spring drought when natural genetic diversity is preserved. These findings have direct implications for assisted migration strategies and seed sourcing guidelines under projected climate scenarios.

evolutionary biology↗

bioRxiv2026

Climate change intensifies rapid genomic selection beyond the ancestral niche of Fagus sylvatica

As climate change accelerates, the persistence of long-lived organisms increasingly depends on their capacity to adapt in situ. While phenotypic plasticity provides an immediate buffer, it remains uncertain whether forest trees can evolve rapidly enough to track shifting climatic niches. Here, we investigate the adaptive potential of European beech (Fagus sylvatica L.), a keystone temperate species, by leveraging different growth classes as a quasi-time-series. This approach allows us to compare growth classes established under the relatively stable climate of the early 20th century against those regenerating under contemporary warming (+1.1{degrees}C global mean temperature increase). Integrating pool-seq data from three growth classes across 43 sites in Germany with satellite-derived environmental stress indicators, we characterised past, current and projected future climate-driven selection. We detected rapid, genome-wide selective sweeps between the oldest and youngest growth classes, particularly in sites already exceeding their historical climatic niche (defined as the 95% confidence interval of pre-warming conditions). Notably, selection signatures have shifted over time: while older classes show signatures related to biotic interactions, younger cohorts exhibit intense selection on genes managing abiotic heat and drought stress. In the warmest regions, we estimated exceptionally high selection coefficients (s{approx}2), suggesting intense selection where beech trees exceed their ancestral niche. In older growth classes, distance and geology account for genetic differences between populations but in young growth classes climate is the primary factor, highlighting the importance of climate change. However, predictive modelling reveals a critical threshold to this resilience. While adaptive potential appears sufficient to maintain population persistence under low-emission scenarios (SSP1-2.6), high-emission trajectories (SSP5-8.5) are projected to rapidly outpace the species evolutionary capacity. These findings demonstrate that while trees can undergo remarkably rapid genomic shifts, the sheer velocity of unmitigated climate change threatens to exceed the fundamental limits of forest adaptation.

evolutionary biology↗

bioRxiv2025

Discovery of a Novel Chimeric Transposase-Transposon System for Advanced Genome Engineering

Transposases revolutionized the field of genetic engineering, yet the scarcity of functional systems remains a challenge. In response, we conducted a metagenomic screening and identified a novel transposase system from Acyrthosiphon pisum. Through systematic optimization, we enhanced nuclear localization, transposon composition, and created a hyperactive transposase variant to boost transposition efficiency. Intriguingly, the combined application of the newly discovered transposase with inverted terminal repeat sequences from a related pea aphid species, Aphis craccivora, further enhanced transposition activity, resulting in the first chimeric transposase system reported so far. We investigated the genomic integration events following transposition in mammalian cells, to understand the underlying mechanisms and optimize the efficiency of transgene integration. This optimized system can expedite the generation of recombinant protein producing CHO cell lines, even surpassing the hyperactive piggyBac system with regards to cell specific productivity. These findings introduce a significant addition to the field of semi-targeted transgene integration technologies, offering substantial potential for enhancing biologics manufacturing.

bioengineering↗

bioRxiv2025

Predicting forest tree leaf phenology under climate change using satellite monitoring and population-based GWAS

Leaf phenology, a critical determinant of plant fitness and ecosystem function, is undergoing rapid shifts due to climate change, yet its complex genetic and environmental drivers remain incompletely understood. Understanding the genetic basis of phenological adaptation is crucial for forecasting forest responses to a changing climate. Here, we integrate multi-year satellite-derived phenology from 46 Fagus sylvatica (European beech) populations across Germany with a population-based genome-wide association study to dissect the environmental and genetic drivers of leaf-out day (LOD) and leaf shedding day (LSD). We show that environmental factors, particularly temperature forcing and water availability, are the primary drivers of LOD variation, while LSD is influenced by a more complex suite of climatic cues. Our genomic analysis identifies candidate genes associated with LOD and LSD, primarily linked to circadian rhythms and dormancy pathways, respectively. Furthermore, genomic prediction models incorporating these loci accurately reconstruct past phenological dynamics, providing a powerful framework to forecast forest vulnerability and adaptation to future climate change.

evolutionary biology↗

bioRxiv2021

dynamAedes: a unified modelling framework for invasive Aedes mosquitoes

O_LIMosquito species belonging to the genus Aedes have attracted the interest of scientists and public health officers for their invasive species traits and efficient capacity of transmitting viruses affecting humans. Some of these species were brought outside their native range by human activities such as trade and tourism, and colonised new regions thanks to a unique combination of eco-physiological traits. C_LIO_LIConsidering mosquito physiological and behavioural traits to understand and predict the spatial and temporal population dynamics is thus a crucial step to develop strategies to mitigate the local densities of invasive Aedes populations. C_LIO_LIHere, we synthesised the life cycle of four invasive Aedes species (Ae. aegypti, Ae. albopictus, Ae. japonicus and Ae. koreicus) in a single multi-scale stochastic modelling framework which we coded in the R package dynamAedes. We designed a stage-based and time-discrete stochastic model driven by temperature, photo-period and inter-specific larval competition that can be applied to three different spatial scales: punctual, local and regional. These spatial scales consider different degrees of spatial complexity and data availability, by accounting for both active and passive dispersal of mosquito species as well as for the heterogeneity of the input temperature data. C_LIO_LIOur overarching aim was to provide a flexible, open-source and user-friendly tool rooted in the most updated knowledge on species biology which could be applied to the management of invasive Aedes populations as well as for more theoretical ecological inquiries. C_LI

ecology↗

bioRxiv2020

Genomic basis of drought resistance in Fagus sylvatica

In the course of global climate change, central Europe is experiencing more frequent and prolonged periods of drought. The drought years 2018 and 2019 affected European beeches (Fagus sylvatica L.) differently: even in the same stand, drought damaged trees neighboured healthy trees, suggesting that the genotype rather than the environment was responsible for this conspicuous pattern. We used this natural experiment to study the genomic basis of drought resistance with Pool-GWAS. Contrasting the extreme phenotypes identified 106 significantly associated SNPs throughout the genome. Most annotated genes with associated SNPs (>70%) were previously implicated in the drought reaction of plants. Non-synonymous substitutions led either to a functional amino acid exchange or premature termination. A SNP-assay with 70 loci allowed predicting drought phenotype in 98.6% of a validation sample of 92 trees. Drought resistance in European beech is a moderately polygenic trait that should respond well to natural selection, selective management, and breeding. Impact StatementEuropean beech harbours substantial genetic variation at genomic loci associated with drought resistance and the loci identified in this study can help to accelerate and monitor adaptation to climate change.

plant biology↗