Description
Ensuring cooperation among formerly autonomous cells has been a central challenge in the evolution of multicellular organisms. One solution is monoclonality, but this option does not eliminate genetic and epigenetic variability, leaving room for exploitative behavior. We therefore hypothesized that embryonic development must be protected by robust regulatory mechanisms that prevent aberrant clones from superseding wild-type cells. Using a genome-wide screen in murine induced pluripotent stem cells, we identified a network of genes (centered on p53, topoisomerase 1, and olfactory receptors) whose downregulation caused the cells to replace wild-type cells, both in vitro and in the mouse embryowithout perturbing normal development. These genes thus appear to fulfill an unexpected role in fostering cell cooperation.