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Sex differences in Drosophila intestinal metabolism contribute to sexually dimorphic infection outcome and alter gut pathogen virulence

We studied the sexual dimorphism of intestinal infections of D. melanogaster. We showed that males exhibit increased a key antioxidant defence system. It allows them to withstand oxidative stress-induced defecation blockage and clear the pathogen from the intestine, resulting in survival. We also showed that the bacteria showed increased expression of several virulence factors in female gut, indicating a change in pathogen behaviour depending on the host they infect (a theory I have been developing since Duneau & Ebert PLoS Biol. 2012). Contribution: I trained the first author to perform the analyses, and I analysed the GWAS.

Seminal fluid proteins as regulation factors for optimizing reproduction: a modeling approach.

Developed a biologically informed theoretical model showing how seminal fluid proteins synchronize sperm and egg release, reducing unfertilized egg production. Identified SP exhaustion as the key synchronization signal and demonstrated that sexual conflict over SP-mediated regulation of female physiology should be limited, though conflict over optimal remating rate remains possible.

Wound-induced eyespots on butterfly wings at the intersection of immune response and pigmentation development

Showed that immune activation modulates wound-induced ectopic eyespot formation in butterfly wings, revealing crosstalk between immune function and pigmentation development.

A within-host infection model to explore tolerance and resistance

Developed a within-host infection model integrating theory and experiments to distinguish between tolerance and resistance mechanisms. Provided a practical experimental framework for explaining individual differences in susceptibility to infection, a methodological foundation applied in subsequent work.

Genetic architecture of plasticity for pigmentation components in Drosophila melanogaster.

Applied genome-wide association mapping in Drosophila melanogaster to dissect the genetic basis of temperature-dependent pigmentation plasticity. Found that different body parts rely on largely independent genetic architectures, challenging the assumption of a common genetic basis for pigmentation plasticity. Contribution: I supervised the student for the genomic analysis and for the validation of allele candidate with functional genetics.

Evolution of sperm morphology in a crustacean genus with fertilization inside an open brood pouch

Based on a recent phylogeny, we identified that Daphnia had among the smallest recorded sperm and studied the evolution of sperm length in this clade. Recommendation: https://doi.org/10.24072/pci.evolbiol.100145

Gut cancer increases the risk of Drosophila being preyed upon by hunting spiders.

Diseased individuals are more preyed upon than healthy individuals. Although this is intuitive, this conventional wisdom has been subjected more to speculation than to empirical study. To test the idea, we genetically induced colon cancer in Drosophila and found that cancerous flies are more frequently predated than healthy ones.

Pathogen within-host dynamics and disease outcome: what can we learn from insect studies?

Parasite proliferations within/on the host form the basis of the outcome of all infectious diseases. However, within-host dynamics are difficult to study in vertebrates, as it requires regularly following pathogen proliferation from the start of the …

Diet composition plastically resizes the Drosophila midgut by affecting cell gain and loss, stem cell-niche coupling and enterocyte size.

We studied the phenotypic plasticity of Drosophila gut in response to glucose level in diet.

Additive and non‐additive effects of day and night temperatures on thermally plastic traits in a model for adaptive seasonal plasticity.

We tested the effects of circadian temperature fluctuations on a series of thermal plasticity traits in a model of adaptive seasonal plasticity, the Bicyclus anynana butterfly.