The genomic basis of copper tolerance inDrosophilais shaped by a complex interplay of regulatory and environmental factors

Abstract

Increases in industrialisation and anthropogenic activity have resulted in an increase in pollutants released into the environment. Of these pollutants, heavy metals such as copper are particularly concerning due to their bio-accumulative nature. Due to its highly heterogeneous distribution and its dual nature as both an essential micronutrient and toxic element, the genetic basis of copper tolerance is likely shaped by a complex interplay of physiological and environmental factors. Drosophila melanogaster, a long-standing sentinel of environmental toxins, is uniquely suited for the study of copper tolerance in arthropods and other more diverse species. In this study, we utilized the natural variation present in multiple populations of D. melanogaster collected across Europe to screen for variation in copper tolerance, which we found to be highly variable both within and between locations. While these collection locations covered a wide range of atmospheric and soil pollution levels, the degree of urbanization at the collection sites, rather than any other combination of environmental factors, was linked to copper tolerance. Moreover, differential expression analysis revealed that metabolism, reproduction, and protease induction contribute to copper response in tolerant and sensitive lines to different degrees. Additionally, the greatest transcriptomic and physiological responses to copper toxicity were seen in the midgut; where preservation of gut acidity is strongly linked to greater tolerance. Overall, our study provides a unique perspective on the genetic and environmental factors that shape copper tolerance in natural D. melanogaster populations and identifies new genes and physiological traits involved in this complex phenotype.

Induction and inhibition of Drosophila X chromosome gene expression are both impeded by the dosage compensation complex

“…In a third dataset, we analyzed the response to infection at 19 different timepoints from 1 to 120 h after injection of Escherichia coli -derived crude lipopolysaccharide ( Schlamp et al 2021 ). Other datasets include exposure to one of 2 different viral infections, copper, starvation, radiation, and cocaine ( Palmer et al 2018 ; Prasad and Hens 2018 ; Harsh et al 2020 ; Baker et al 2021 ; de Oliveira et al 2021 ; Green et al 2021 ). A full list of accession numbers is provided in Supplementary File 1 .…”

DrosOmics: a comparative genomics browser to explore omics data in natural populations ofD. melanogaster

“…Note that the current version of DrosOmics provides gene annotations that were transferred to each genome from the reference release 6 of D. melanogaster (Larkin et al, 2021). Functional -omics data for 26 genomes were retrieved from previous research (Everett et al, 2020;Salces-Ortiz et al, 2020;Green et al, 2021;Horváth et al, 2022; Table 2 and Table S1) or are reported here for the first time (Supplemental Material, Table S1). Genome and functional annotations can be graphically displayed along the chromosome arms for multiple genomes simultaneously (Figure 1 and Table 2).…”

“…Note that the current version of DrosOmics provides gene annotations that were transferred to each genome from the reference release 6 of D. melanogaster. Functional -omics data for 26 genomes were retrieved from previous research(Everett et al 2020;Salces-Ortiz et al 2020;Green et al 2022;Horváth et al 2022; Table2 and Table…”