Research

The goal of the lab is to understand how evolution sculpts nervous systems, giving rise to novel behaviours. Studying the evolutionary forces imposed on neural circuits can provide us with important insights on how brains work and what goes wrong in diseases. We study these questions using as a model the olfactory systems of several fly species, some of which are pests or contribute to the spread of diseases.

We have a multidisciplinary approach, combining a variety of methodologies including field-work, bioinformatics, electrophysiology, imaging, behavioural analysis, and genetic manipulations. Here you can find information on the lab projects.

Evolution of central neural circuits

PNsSensory evoked behaviours can evolve through changes in the periphery, at the level of sensory neurons, or via modification of the way sensory information is processed in the brain by central neural circuits. There is increasing understanding of how receptors and sensory neurons evolve across different species. However, we know little about how central neural circuits are re-shaped during evolution. We are investigating this question using model olfactory pathways in different Drosophila species with divergent behaviors, yet conserved periphery.

Ecology and evolution of olfactory systems under fluctuating selection

evol-fly

How selection shapes olfactory circuits is still poorly understood. An ideal place to look into this question is across populations subjected to recent and ongoing selection. We are studying this question in populations of D. erecta, a West African fly species that feeds on a host with seasonal availability that imposes fluctuating selection.

Function, mechanisms and evolution of neuron-specific read-through

senior22We previously found that some pseudogenes containing premature stop codons, and are thus supposedly non-functional, are expressed and function thanks to neuron-specific read-through of their stop codon (Prieto-Godino et al. 2016 Nature). We are interested in understanding how general this phenomenon is,  the mechanisms of this tissue-specific read-through, and its consequences for evolution and diseases.

Evolution of neuron numbers

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We and others have previously shown an expansion in the number of olfactory sensory neurons expressing receptors that detect species’ host key volatiles (Prieto-Godino et al. 2017 Neuron, Dekker et al. 2006 Curr Biol, Linz et al. 2008 Proc R Soc). In collaboration with Roman Arguello and Thomas Auer from Richard Benton‘s lab, we are mapping the genetic loci underlying this evolutionary trait.

Evolution of olfactory receptors in tsetse flies

tsetse

Tsetse flies (Glossina sp.) are the sole vector for African trypanosomasis, which causes sleeping sickness in humans and nagana in cattle – both of which constitute an important burden particularly in rural areas of Africa. Different tsetse fly species have different host preferences, and the genomes of five of these have recently been sequenced (Macharia et al. 2016 PLoS Negl Trop Dis). We are investigating how the olfactory receptors of tsetse flies detect hosts odours and how they have evolved in different species.