Gianni Liti The recipe for the evolution of Saccharomyces yeast

Revealing the genetic architecture of Saccharomyces

Interactions between different species of micro-organisms very probably have an impact on their evolutionary histories. To date, the underlying mechanisms that generate these biological phenomena are not known. What is certain is that Saccharomyces microbial communities vary according to geography and ecology, i.e. the environments in which they live, and their relationship with these environments.

The research carried out by Gianni Liti and his team has contributed to the development of Saccharomyces yeast as a model for biologists, and more specifically for the study of population genomics. The researcher recently set about analyzing 1,011 Saccharomyces cerevisiae genomes, corresponding to a large proportion of the natural genetic variation of this species on Earth. As a result, he now has one of the best understandings of diversity in a eukaryotic model organism. This work is crucial for the study of other eukaryotes, such as humans, animals and plants, all of which are characterized by the presence of a nucleus containing DNA at the heart of their cells.

Deciphering variations within genomes

By undertaking genomic studies, which look at all the genes and chromosomes in an organism, Gianni Liti has revealed the Asian origin of the Saccharomyces yeast. He also highlighted the genetic differences between domesticated and wild species. His work has, among other things, revealed the impact of human activities on the structure of Saccharomyces populations.

Using cutting-edge genetic approaches, he is now seeking to understand how Saccharomyces yeasts interact with the microbial communities that coexist with them in a given environment.

Understanding relationships between micro-organisms at all levels

Gianni Liti and his team plan to provide an overview of microbial interactions of the yeast Saccharomyces. Their idea is to measure the impact of these interactions on genes, their expression and the life cycle of individuals.

Impulscience^® will enable them to elucidate the microbial communities of Saccharomyces across hundreds of ecological niches, both wild and domestic. They will then analyze, in the laboratory, the interactions between Saccharomyces cells and other species in microbial communities. They will also assess the impact of these interactions on the transfer of certain genes between species or between yeast cells infected by bacteria. The ultimate aim of this project is therefore to reveal the molecular basis of interactions between species and to deduce the role they have played in the evolution of Saccharomyces species.