Axe 1 : Understanding and shedding light on evolutionary mecanisms

Our research questions focus on the mechanisms involved in the evolution of species and populations. In particular, we aim to understand how these mechanisms influence the adaptation and dynamics of biological diversity on macro- and micro-evolutionary scales. To this end, we are developing research around three fundamental questions:

Mechanisms of macro-evolutionary divergence

We are interested in the process of speciation, using domestication as a model to decipher the mechanisms and determinants of reproductive isolation. We also use the Brassica complex as a model to study genomic changes associated with allopolyploid speciation and their contribution to adaptation. We study the evolution of sexual reproduction using the Nakaseomyces yeast complex. Finally, we use the Ranunculaceae family to study the molecular mechanisms involved in the morphological diversification of petals.

Plasticity of genome structure, expression and regulation

To understand the forces involved in adaptation, we analyze the dynamics of structural variants, their molecular origins and their functional implications, using maize as a model. We are also interested in the genetic and epigenetic origins of transcriptional variability in this species, and its implication in the variability of gene expression regulatory networks during development and in response to the environment. Finally, we explore the genetic and epigenetic variability of transposable elements, and their contribution to the regulation of these networks.

Mechanisms influencing genetic diversity

We study the genetic determinants of quantitative variation in meiotic recombination and interference in the yeast Saccharomyces cerevisiae. We approach the question of genetic load from the angle of hybrid vigor and inbreeding depression, examining the role of epistasis and genetic linkage. Using divergent selection experiments, we analyze how specific regimes of strong drift and strong selection can contribute to adaptation from new mutations. Finally, we develop models that take into account the complexity of genotype-phenotype interaction to study the evolution of life-history traits through the modification of biological networks.

Methodologies

To tackle these questions, we combine experimental and theoretical approaches. These include the generation of innovative biological material, the generation of large molecular data sets at multiple scales (genome, epigenome, transcriptome, proteome) and their analysis using bioinformatics and biostatistics approaches, as well as modeling approaches in population genetics and quantitative genetics.