Metabolic constraints in the evolution of biochemical networks

Metabolism and evolution are closely connected: if a mutation incurs extra energetic costs for an organism, there is a baseline selective disadvantage that may or may not be compensated for by other adaptive effects. In our recent work, we prove a mathematical relationship between the added bioenergetic burden of newly emerging biochemical networks and the fitness disadvantage for the organism. The derivation is based on a general growth model and can be extended to capture the effects of other limiting factors constraining the growth. I will discuss the significance of this contribution from metabolic expenditures in the course of evolution, by considering the population dynamics. As an example, I will illustrate the trade-offs in the evolution of noise control in microRNA-regulated gene networks which play a critical role by controlling developmental processes of complex organisms and related diseases.