Animal Sciences & Health
Development and Evolution
The Institute of Biology Leiden has a long-standing tradition in evolutionary developmental biology (evo-devo). We aim not only to unravel the genetic and developmental basis of evolutionary change, but also to study the developmental system under environmental challenge. Our interest in the impact of early life stress on disease susceptibility and the development of behavioural patterns closely links our evo-devo research to other research themes under Animal Sciences & Health.
Evolution of animal forms and functions
A main goal of evo-devo research is to understand the genetic and developmental basis of evolutionary change. Expanding from the standard models for vertebrate development such as zebrafish and chicken, we compare gene expression patterns in embryos of different amphibian, reptile, bird, and mammalian species to reveal species differences in the gene regulatory changes underlying alterations in animal morphology. This work has shed new light on the evolution of limb development. Furthermore, the evolution and development of the snake venom delivery system is a major focus of current work. Molecular genetic techniques such as RNAi are used to study the evolution of gene function in a range of insect models; the fruit fly Drosophila melanogaster and the beetle Tribolium castaneum being the most prominent ones. Comparative genomics and transcriptomics complete our approach. These lines of research contribute to a fundamental understanding of the molecular basis of animal body plan evolution.
As van Valen famously argued, evolution is the control of development by ecology. Organisms develop in a changing environment, and are constantly challenged by biotic and abiotic factors. This requires a diverse scope of adaptations in different organisms. In this context we use the zebrafish model to study how animals control their energy metabolism. In snakes, we study how their venom systems evolved to develop toxicity against a range of prey species. In insects, we study the evolutionary transition from an ancestral marine to a current terrestrial life style. This transition coincided with the evolution of extraembryonic membranes. These function to protect the embryo against desiccation, and to defend it against invading microbes. This line of research strengthens the expertise of the Animal Sciences & Health research cluster in innate immunity and tightly links to the Mechanisms of Disease theme. Together with ecologists in our institute, and in biological control companies, we study ways to break the egg defences of pest insects.
Applications and collaborations
Our evo-devo research creates several major opportunities to address issues in human health. Our comparative approach has identified a plethora of natural products including peptides from snake venoms, which are a grossly under-explored resource of potential drug candidates. Amongst others, these products are screened for antimicrobial activity together with the Microbial Biotechnology & Health cluster and the Naturalis Biodiversity Center, Leiden. In one interdisciplinary line of research, zebrafish deficient in the metabolic pathways that mediate starvation responses during larval development are used to screen for tumor-repressing compounds, as the metabolic stress of these larvae resembles that of tumors. These applied lines of research connect our cluster to the Natural Products Lab, the LUMC, and LACDR, and places this research in the general Healthy Lives in a Changing World theme of the Science Faculty.