Intracellular pH controls Wnt signaling downstream of glycolysis in the vertebrate embryo

Formation of the body of vertebrate embryos proceeds sequentially by posterior addition of tissues. While this process depends on aerobic glycolysis acting upstream of Wnt signaling in tail bud cells, the molecular details of this regulation are unknown. Here we used chicken embryos and human tail bud-like cells differentiated in vitro from iPS cells to show that glycolysis acts by increasing the intracellular pH (pHi) of tail bud cells. This promotes β-catenin acetylation leading to Wnt signaling activation and the choice of a mesodermal fate at the expense of the neural fate in tail bud precursors. Our data suggest that by increasing the pHi of tail bud cells, aerobic glycolysis creates a favorable chemical environment for non-enzymatic acetylation of β-catenin, ultimately triggering Wnt signaling.