Shortly after a mouse embryo starts to form, some of its stem cells undergo a dramatic metabolic shift to enter the next stage of development, researchers report today. In fact, these stem cells start using and producing energy like cancer cells. “These findings not only have implications for stem cell research and the study of how embryos grow and take shape, but also for cancer therapy,” said the senior author of the study, Hannele Ruohola-Baker, University of Washington professor of biochemistry. The metabolic transition they discovered occurs very early as the mouse embryo, barely more than a speck of dividing cells, implants in the mother’s uterus. The change is driven by low oxygen conditions, Ruohola-Baker explained. The researchers also saw a specific type of biochemical slowdown in the stem cells’ mitochondria -- the cells’ powerhouses. This phenomenon previously was associated with aging and disease and this was the first example of the same downshift controlling normal early embryonic development.