Metabolic Plasticity drives Development during Mammalian Embryogenesis

Preimplantation mouse embryos interact minimally with their environment, and development is largely driven by metabolic processes. During the earliest cleavage stages, metabolism is rigid, with maternal deposits enforcing a redox state that facilitates zygotic genome activation. As maternal control falls, metabolic shuttles are activated, increasing glycolysis and equilibrating the TCA cycle. The resulting flexibility of nutrient utilization and metabolic plasticity facilitates unidirectional developmental progression such that later stage embryos proceed to form blastocysts without any exogenously added nutrients. We explore the mechanisms that govern this choreographed sequence that balances the deposition, degradation, synthesis and function of metabolic enzymes with redox control, bioenergetics and biosynthesis. Cancer cells follow a distinct metabolic strategy from that of the preimplantation embryo. However, important shared features emerge under reductive stress. We conclude that metabolic plasticity drives normal development while stress conditions mimic hallmark events in Cancer Metabolism.