Evolution of phenotypes: understanding diversity and the role of plasticity in adaptation to new environments

Trabajo presentado al Meeting of the Society for Molecular Biology and Evolution (SMBE), celebrado en Manchester (UK) del 21 al 25 de julio de 2019.The Baker's yeast Saccharomyces cerevisiaeis one of the most important biotechnologically microbes because of its ability to produce and tolerate high levels of ethanol. Due to these properties, much interest has been put in understanding the genetic underpinnings of alcohol tolerance to improve the quality and productions of the products. A reason study by Voordeckers et al (2015) has shown that adaptation to high ethanol tolerance involves point mutation, copy number variation, ploidy changes, and clonal interference. Nonetheless, the transcriptional re-wiring occurring during the response or adaptation to ethanol and its importance in comparison with the contribution to mutations in coding changes has not been explored. With both copy number variation and change of ploidy involved in the adaptation to ethanol, indicates that duplication plays an important role in the adaptation. We have already observed in our previous studies that ancient duplicates (small-scale and whole genome duplicates) play an important role in acute ethanol response (Mattenbergeret al. 2017). Here we use experimental evolution of S. cerevisiaeto uncover the transcriptional rewiring during ethanol adaptation and its link with gene duplication. First the populations of S. cerevisiaewere evolved for hundreds of generations for the purpose of diversification and later we evolved the populations with ethanol being the only carbon source. Little overlap was observed between enriched functional categories of up-regulated genes in response and adaptation to ethanol. In particular, we see a significantly larger proportion of duplicated genes responding to ethanol stress than singletons. Moreover, the fold change in duplicated genes was higher compared to singletons. All of which indicate that duplicated genes play a central role in the acute and chronic response to ethanol.Peer reviewe