RT Journal Article SR Electronic T1 Genome-wide selection signatures reveal widespread synergistic effects of culture conditions and temperature stress in Drosophila melanogaster JF bioRxiv FD Cold Spring Harbor Laboratory SP 2021.11.09.467935 DO 10.1101/2021.11.09.467935 A1 Claire, Burny A1 Viola, Nolte A1 Marlies, Dolezal A1 Christian, Schlötterer YR 2021 UL http://biorxiv.org/content/early/2021/11/11/2021.11.09.467935.abstract AB Experimental evolution combined with whole-genome sequencing is a powerful approach to study the adaptive architecture of selected traits, in particular when replicated experimental populations evolving in opposite selective conditions (e.g. hot vs. cold temperature) are compared. Nevertheless, such comparisons could be affected by environmental effects shared between selective regimes (e.g. laboratory adaptation), which complicate the interpretation of selection signatures. Here, we used an experimental design, which takes advantage of the simplicity of selection signatures from founder populations with reduced variation, to study the fitness consequences of the laboratory environment (culture conditions) at two temperature regimes. After 20 generations of adaptation at 18°C and 29°C, strong genome-wide selection signatures were observed. About one third of the selection signatures can be either attributed to temperature effects, laboratory adaptation or the joint effects of both. The fitness consequences reflecting the combined effects of temperature and laboratory adaptation were more extreme in the hot environment for 83% of the affected genomic regions, fitting the pattern of larger expression differences between founders at 29°C. We propose that evolve and resequence (E&R) with reduced genetic variation allows to study genome-wide fitness consequences driven by the interaction of multiple environmental factors.Competing Interest StatementThe authors have declared no competing interest.