The history of life on Earth is characterized by major transitions in organismal complexity. It has been argued that cellular complexification requires a major energy influx, but this notion remains contentious. What is the relationship between complexity and energy? What are the energetic costs of cellular complexity? We envisage that new genes take away a larger fraction of cellular resources before their functions are evolutionarily optimized, and that more complex cells necessarily devote a smaller fraction of their available resources to growth and reproduction.
This project aims to investigate the short- and long-term evolutionary consequences of increases in cellular complexity. To do this, we will (1) investigate the genome-, transcriptome-, and proteome-level changes during the evolutionary optimization of a weakly functional gene (a nascent gene analog), and (2) characterize the proteome allocation strategies of phylogenetically diverse cells with varying degrees of complexity. This project will reveal the evolutionary path taken, and costs incurred, by new genes, and how long-term increases in complexity have shaped the proteome allocation programs of cells. The outcome will further clarify the evolutionary relationship between energy and cellular complexity and thus has the potential to reconcile opposing views in the field of cell evolution. Ultimately, this will lead to a better understanding of how organismal complexity has increased in evolution.
