Understanding Gene Sensitivity and Evolutionary Relationships in the Stress Responses of Model Species

Abstract

Stress is prevalent in all forms of life and thus an organism’s quick and appropriate response is of critical importance to ensure survival. Organisms coordinate these responses at the genomic level with alterations in gene expression. While some previous studies have analyzed general or specific stress responses within a given species at the genomic level, little work has been done to analyze genomic stress responses across species. Here, in this meta-analysis, I characterize the stress responses of four model species: S. cerevisiae, D. melanogaster, M. Musculus, and H. Sapiens across different stress conditions (nutritional, heat shock, oxidative, and immunological). Using Gene Ontology tests, I analyze what types of genes are most commonly altered or more susceptible to changes in expression during stress as well as the types of genes that are more resistant to expression changes or buffered during stress. I also ask how evolutionarily conserved genes are regulated during times of stress. It is concluded that while some aspects of the stress response are highly conserved such as genes involved in the Unfolded Protein Response, other components are species-specific. I also find that evolutionarily conserved genes are no more or less likely to be involved in a stress response or buffered except in D. melanogaster. This study also provides examples of stress serving as a driver of adaptive evolution and may also offer useful information for gene therapy targets for conditions that impose stress on cells.