The adaptable genome
A large parts of the genome has evolved to deal with the ecological interactions of an organism with its environment. Most of the traits or processes that have evolved for these interactions are complex, with many genes involved, and often the ability to respond to variation in the environmental conditions. For the analysis of such a complex genetic architecture of traits and processes, the genomic toolbox is required. These tools allows us, for the first time, to trace the impact of the ecological interactions on the evolution of the genome. We aim to elucidate the genomic variation and genetic networks underlying the evolution of complex traits in ecological interactions, using a combination of experimentation, genomic approaches and bioinformatics.
We study the evolutionary genomics of ecological interactions in Drosophila fruitflies, where we can combine our extensive understanding of their ecology with the formidable molecular toolbox and knowledge on mechanistic processes for various life history traits. In my group, we investigate the changes in the genome that occur during 1) host-parasite co-evolution, 2) competitive turf wars for food, 3) sexual conflicts, and 4) the composition of the microbiome.
1) Host-parasite co-evolution
Parasitoids are insects that lay their eggs in or on other
insects (their "hosts"), which are eventually killed while the
developing parasitoid feeds on the host. To survive the lethal
infection by parasitoids, some species
of Drosophila can launch a potent cellular
immune defense. The ability to resist parasitoid wasps varies
hugely, both among and within species of
the Drosophila genus, from completely absent in
some species and natural populations to high resistance in others.
Using a combination of phenotypic assays and genomics
approaches, we identify genomic changes associated
with gains and losses of parasitoid resistance. By studying and exploiting the large variation in immunity within and among Drosophila species, we aim to better understand the intricate genetic networks that underlie variation in immunity, and to map how the genome changes during the evolution of immunity.
- Laura Salazar Jaramillo: Comparative genomics of parasitoid resistance in Drosophila species
- Kirsten M. Jalvingh: The genetic basis of parasitoid resistance of D. melanogaster in artificially selections population
- Sylvia Gerritsma: Genomic variation in natural populations of D. melanogaster contributing to resistance against the parasitoid Asobara tabida
- Peter Hoitinga: Evolution of complex genetic networks in immunity
2) Competitive interactions
Competition among species is a major organizing force in community ecology, and species can evolve complex strategies to survive competition. Two major players for ecosystem function are filamentous fungi and insects, and the turf wars between these taxa resulted in various adaptions and counter-adaptations. Fungi can engage in chemical warfare producing various insecticidal toxins, while insects can evolve detoxification mechanisms, immunity and behavioural adaptations (“social immunity”).
- Monika Trienens: Functional genomic analysis of the co-evolutionary arms race between Drosophila and Aspergillis
3) Sexual conflict
In many animals, including humans, males release both sperm and semen inside the female’s body during sex. The effects of semen proteins can benefit both sperm and eggs, but intriguingly they can also favour the interests of males whilst generating costs in females, resulting in sexual conflict. This manipulation of one sex by the other through molecular interactions was discovered in studies using the fruitfly Drosophila melanogaster. One enigmatic semen protein of the fruitfly, ‘Sex Peptide’ (SP), generates strikingly diverse changes in the behaviour, reproductive and immune system of the female. These changes benefit males by increasing their share of paternity, but can also result in costs in females, therefore mediating sexual conflict.
- Jessy Rouhana: Evolutionary genomics of the enigmatic Sex Peptide: a male ‘master regulator’ of female reproduction
4) IPM strategies for the invasive Drosophila suzukii
The Spotted Wing Drosophila (SWD), Drosophila suzukii, is an invasive fruit fly from Asia that infests ripening fruit. It is rapidly spreading north in Europe and already causes millions of euros of damage in the fruit industry. We aim to capitalize on our extensive expertise in Drosophila chemical ecology, insect reproduction, insect evolutionary genetics, and interactions with parasitoids and pathogens, to develop innovative and locally attuned approaches for the management of this invasive pest.
- Aurore Panel: Fundamentals of D. suzukii biology in the Netherlands
- Astrid Kruitwagen: Biological control strategies of the invasive pest Drosophila suzukii: selective breeding of natural enemies
- Jeroen Alkema (WUR): Crop protection strategies of the invasive pest Drosophila suzukii: a "push-pull" approach
- Karla Escobedo Quevedo:Development and effectiveness of bait sprays as part of Integrated Pest Management (IPM) of Drosophila suzukii
The billions of microbiota that live inside the body of an organism (‘the host’) have a much larger impact on the host than was previously appreciated. The immense community of microbes that reside in the gut, the skin or anywhere else in the body is collectively known as the microbiome. Recent experimental evidence emphasizes the huge influences of the microbiome on the phenotype of the host. The composition of the microbiome of a particular host is greatly dependent on the food, on environmental factors and on genetic factors of the host itself.
- Maria Chaplinska: Microbiome of natural D. melanogaster populations
- Kiran Gurung: The role of microbial symbionts in the niche shift of Drososphila suzukii