Unique genetic signatures of local adaptation over space and time for diapause, an ecologically relevant complex trait, inDrosophila melanogaster

bioRxiv (Cold Spring Harbor Laboratory), Journal Year: 2020, Volume and Issue: unknown

Published: May 8, 2020

Abstract Organisms living in seasonally variable environments utilize cues such as light and temperature to induce plastic responses, enabling them exploit favorable seasons avoid unfavorable ones. Local adapation can result variation seasonal but the genetic basis evolutionary history of this remains elusive. Many insects, including Drosophila melanogaster, are able undergo an arrest reproductive development (diapause) response conditions. In D. melanogaster , ability diapause is more common high latitude populations, where flies endure harsher winters, spring, reflecting differential survivorship overwintering populations. Using a novel hybrid swarm-based genome wide association study, we examined ovarian diapause. We exposed outbred females different temperatures day lengths, characterized for over 2800 flies, reconstructed their complete, phased genomes. found that diapause, scored at two developmental cutoffs, has modest heritability, identified hundreds SNPs associated with each phenotypes. Alleles one phenotypes tend be higher latitudes, these alleles do not show predictable variation. The collective signal many small-effect, clinally varying plausibly explain latitudinal seen North America. segregating relatively frequencies Zambia, suggesting relies on ancestral polymorphisms, both pro- anti-diapause have experienced selection Finally, utilized outdoor mesocosms track under natural swarms reared outdoors evolved increased propensity late fall, whereas indoor control populations no change. Our results indicate complex, quantitative trait patterns across time space. Author Summary Animals exhibit diverse strategies cope conditions temperate, environments. model fly, enter physiological state known winter-like Diapause by absence egg maturation thought conserve energy survival during stressful times. from latitudes offspring recently overwintered. Therefore, been recent adaptation temperate climates. variants affect some vary predictably little repeated seasonality diapause-associated variants, our winter when they were Combined, suggest evolve differently space time. find evidence environments; rather, quite may promote stresses other than cold. provide future targets research into underpinnings ecologically relevant trait.

Language: Английский

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Reconstructing the Invasion Route of the P-Element inDrosophila melanogasterUsing Extant Population Samples

Genome Biology and Evolution, Journal Year: 2020, Volume and Issue: 12(11), P. 2139 - 2152

Published: Sept. 8, 2020

Abstract The P-element, one of the best understood eukaryotic transposable elements, spread in natural Drosophila melanogaster populations last century. It invaded American first and later to Old World. Inferring this invasion route was made possible by a unique resource available D. melanogaster: Many strains sampled from different locations over course Here, we test hypothesis that P-element may be reconstructed extant population samples using internal deletions (IDs) as markers. These IDs arise at high rate when DNA transposons, such are active. We suggest inferring routes is as: 1) fraction increases successively populations, which also explains striking differences ID content between European 2) end up with similar sets IDs. This approach allowed us reconstruct reasonable accuracy. Our sheds light on unknown timing African populations: were after but before populations. Simulations TE invasions spatially distributed confirm allow infer routes. might applicable other transposons host species.

Language: Английский

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Genomic Responses to Climate Change: Making the Most of the Drosophila Model

Frontiers in Genetics, Journal Year: 2021, Volume and Issue: 12

Published: July 13, 2021

It is pressing to understand how animal populations evolve in response climate change. We argue that new sequencing technologies and the use of historical samples are opening unprecedented opportunities investigate genome-wide responses changing environments. However, there important challenges interpreting emerging findings. First, it essential differentiate genetic adaptation from phenotypic plasticity. Second, extremely difficult map genotype, phenotype, fitness. Third, neutral demographic processes natural selection affect variation similar ways. Drosophila melanogaster , a classical model organism with decades research, uniquely suited overcome most these challenges. In near future, long-term time series datasets D. will provide exciting study recent change lay groundwork for related research non-model systems.

Language: Английский

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Allelic polymorphism at foxo contributes to local adaptation in Drosophila melanogaster

bioRxiv (Cold Spring Harbor Laboratory), Journal Year: 2018, Volume and Issue: unknown

Published: Nov. 16, 2018

Abstract The insulin insulin-like growth factor signaling pathway has been hypothesized as a major determinant of life history profiles that vary adaptively in natural populations. In Drosophila melanogaster , multiple components this predictably with latitude; includes foxo conserved gene regulates and pleiotropic effects on variety fitness-associated traits. We allelic variation at underlies genetic variance for traits latitude reflect local adaptation. To evaluate this, we generated recombinant outbred populations which the focal allele was homozygous fixed either common high or low genomic background randomized across 20 inbred lines. After eight generations recombination, experimental were phenotyped series related to function. Our results demonstrate predictable body size starvation tolerance, but not development time. These patterns mirror those observed collected latitudinal gradient eastern U.S.: clines tolerance size, time exhibited no association latitude. Furthermore, differences between genotypes equivalent sampled from extremes, although contribution less pronounced. suggest is contributor adaptive model.

Language: Английский

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Rapid evolution of learning and reproduction in natural populations ofDrosophila melanogaster

bioRxiv (Cold Spring Harbor Laboratory), Journal Year: 2018, Volume and Issue: unknown

Published: March 25, 2018

Abstract Learning is a general mechanism of adaptive behavioural plasticity whose benefits and costs depend on the environment. Thus, seasonal oscillations in temperate environments between winter summer might produce cyclical selection pressures that would drive rapid evolution learning performance multivoltine populations. To test this hypothesis, we investigated evolutionary dynamics ability over timescale natural population Drosophila melanogaster . Associative was tested common garden-raised flies collected from nature spring fall three consecutive years. The consistently learned better than flies, revealing improved nature. Fecundity showed opposite pattern, suggesting trade-off reproduction. This also held within population: more fecund individual females less well. mediated at least part by polymorphism RNA binding protein couch potato ( cpo ), with genotype favoured during showing poorer higher fecundity winter. can performance, but may be driven trade-offs generated pleiotropic effects causative alleles selected for other reasons.

Language: Английский

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