Project description
Putting hybrid genomes under the microscope
Interspecies hybridisation has received great attention as a breeding technique to generate species with improved properties or desirable characters. However, hybrids are often infertile and hybrid genomes present with signatures of genome restructuring and instability. When and how genome instability arises in hybrids and in what way it affects the evolution of organisms that have undergone hybridization events remains elusive. The Marie Skłodowska-Curie Actions (MSCA) EARLYBRID project will use Saccharomyces yeast as a model to study the parental and environmental factors that affect genome stability in interspecies hybridisation. Researchers will also investigate the structure and complexity of hybrid genomes alongside gene expression and hybrid viability, offering a more holistic view on their dynamic interplay. Collectively, EARLYBRID-generated knowledge will be useful in biotechnology and plant breeding applications.
Objective
Hybridization has shaped the evolution of every kingdom of life. By combining highly diverged genomes, hybridization can drive genetic exchange across lineages. Hybrid genomes often present hallmarks of genome instability, but direct proof of higher rates of mutational events are lacking. What triggers genome instability in hybrids and when it arises remains a mystery. To address this question, I propose to investigate early hybrid history. I seek to conduct a comprehensive characterization of hybrid lethality, genome stability, and gene expression, employing Saccharomyces yeast as a model, due to their tractability and ability to form hybrids despite extreme sequence divergence between parental founders. These studies will focus on the early phases of interspecies hybrid clonal expansion that immediately follow zygote formation. I will first quantify how parental divergence in conjunction with environment influence the genome stability and viability of asexually expanding hybrids. Next, I will combine ultra-long read DNA-sequencing with single-cell RNA-sequencing, to assess the structure and complexity of hybrid genomes, how they evolve over time, and the genomic heterogeneity of hybrid cell populations with single-cell resolution. Finally, by conducting transcriptomic analysis of clonally expanding hybrids, I will determine gene expression dynamics at the onset of hybridization and whether the parental subgenomes converge toward similar gene expression signatures to enter the aforementioned stabilization phase. Mechanistic characterization of the interaction between hybrid viability, genome instability and gene expression phenotypes will provide an unprecedented view of how early hybrid genomes arise, are maintained and evolve.
Fields of science
Keywords
Programme(s)
- HORIZON.1.2 - Marie Skłodowska-Curie Actions (MSCA) Main Programme
Funding Scheme
MSCA-PF - MSCA-PFCoordinator
75794 Paris
France