Grant: Discovery Grants Program - Individual

Across the tree of life, genome content and organization are highly diverse. Deciphering the molecular mechanisms that drive this diversity is critical in the current context of global environmental change. Indeed, human activities affect natural ecological niches. However, understanding the impact of these disturbances on genome stability and consequently on evolution and adaptation is fundamental if we are to anticipate their consequences on biodiversity. An increased rate of alterations in the genome, known as genomic instability (GIN), leads to a higher frequency of mutations, chromosomal variations, and polyploidy. Although excessive GIN can be deleterious, moderate GIN may have several advantages. Increasing genetic variability in a population of cells could facilitate adaptation to stressful environments. However, the factors influencing the emergence of GIN and to which extent it may impact adaptation and speciation processes are still poorly understood. The classical evolutionary theory states that the mutation rate of an organism is independent of the environmental conditions. However, an increased mutation rate has been observed in bacteria when exposed to antibiotics. This suggests that environmental changes can influence not only natural selection, but also the amount and type of mutations available for selection. Despite advances in studies on the impact of environmental changes on different animal and plant species, how human activities affect genome stability and, consequently the adaptive potential of species remains underexplored. Our research program aims to use multidisciplinary approaches to investigate the impact of environmental stress caused by human activities on genome stability and its consequences on the adaptive potential using yeast as a model. First, we will determine the impact of the proximity to urban areas and industries on genetic and phenotypic diversity as well as on genome stability of natural yeast populations. We will assess whether yeast strains isolated in urban areas have a higher GIN than those from rural areas. Secondly, we will evaluate the impact of the presence of pollutants (nanoplastic, arsenic), temperature increase and their combination on genome stability and cellular physiology of yeast strains with different levels of intrinsic GIN. Finally, we will explore the effect of these pollutants, temperature increase and their combination on the adaptation rate of yeast strains with different levels of intrinsic GIN. This program meets the pressing needs to assess the impact of major transitions, such as environmental changes on biodiversity, and to address the issues of its conservation, restoration and mobilization. Overall, in addition to the training of 7 HQP, this program will help to understand the impact of human activities on eukaryotic cell diversity and help decision-makers target the necessary efforts we need to create an ecologically sustainable future in Canada and all over the world