EDIOS · Evolutionary development of the insect olfactory system
Horizon 2020 — Marie Skłodowska-Curie Actions
- Duration
- 2018-06-01 → 2021-02-28
- EU contribution
- €187,420
- Participants
- 1
- Scheme
- MSCA-IF
Lines connect the coordinator with its partners.
Results in brief
Evolutionary development of the insect olfactory system
The evolution of novel cell types, developmental programs, and connective properties in the nervous system allows for behavioral innovation and unique mental capabilities across the metazoan tree of life, including those observed in humans. Nonetheless, we still know essentially nothing about the changes in the genetic code which lead to these evolutionary novelties. The insect olfactory system is an excellent model for studying these changes because of the massive diversity in cellular and super-cellular makeup, rapid evolution of these structures, and clear phenotypic relevance. In the insect olfactory system, specific populations of sensory cells (olfactory sensory neurons or OSNs) express receptors which respond to ecologically relevant odorants. New cell populations can evolve to increase the olfactory resolution towards specific chemical classes or confer novel odorant sensitivity. These cells must also form new neural connections and pathways within the brain to allow this novel sensory information to be processed. If we can understand the specific genetic changes leading to new populations and giving them their novel connective properties, we will be able to understand the evolution of behavioral novelty from the genomic through the cellular and neuroanatomical levels. In order to understand the evolutionary development of the insect olfactory system, I set out to examine gene expression in single cells throughout the course of olfactory system development, examine the co-evolution of gene expression and OSN population diversity in ants, and validate candidate genes for function in OSN development and identity using functional genetics in vinegar flies.
Data: CORDIS, © European Union
Project objective
An outstanding challenge at the crossroads of neuro, evolutionary, and developmental biology is explaining how molecular changes give rise to the alternate neural morphologies and physiologies that underlie the behavioral adaptations of animals. I propose to address this by examining the EvoDevo of the olfactory system in insects. The number and physiological properties of olfactory sensory neuron (OSN) populations determine the sensitivity and specificity of olfactory responses. Evolution of new OSN populations requires changes in cell-type diversification, receptor repertoire, receptor regulation, and axonal targeting. However, it is unknown how these factors co-evolve. I will use three complementary methods to investigate the genetic basis of OSN evolution in insects. First, I will utilize the large OSN size in the silk moth to conduct single-cell RNA-seq of OSNs during development, examining transcriptomic differences between related OSN lineages within a species. Second, I will utilize the rapid evolution of the ant olfactory system to investigate comparative gene expression and neurodevelopment in closely related species with divergent olfactory systems. By examining a range of more and less diverged species/OSN populations, I will be able to observe the gene expression changes accompanying OSN evolution. Third, I will test candidate genes by using gene modification in the genetically tractable vinegar fly. This research will show how new OSN circuits evolve, facilitating olfactory system adaptation. More generally, this research will show how genomic changes wrought by evolution can give rise to novel neural circuitries- in essence showing how brains can evolve.
Original text from CORDIS.
Participants
- UNIVERSITE DE LAUSANNE · LAUSANNECoordinatorSwitzerland
Links
Data: CORDIS, © European Union