Maternal Huluwa dictates the embryonic body axis through β-catenin in vertebrates

Maternal factor sets axis The vertebrate body form changes from the round shape of the fertilized egg to a cylindrical shape when the body plan is established. However, it is unknown whether a maternal factor controls this body axis formation. Yan et al. identified such a maternal factor and named it Huluwa. Loss of maternal Huluwa, a transmembrane protein, in zebrafish or frog eggs resulted in embryos that lacked the body axis and were missing the head and dorsoanterior tissues. Huluwa promoted Axin degradation, likely independent of Wnt ligand–receptor signaling, to protect β-catenin from degradation and induce body axis development during embryogenesis. Science , this issue p. eaat1045