BMP signaling is required for the generation of primordial germ cells in an insect

Abstract

Many model organisms specify germ cells using maternally supplied germ-line determinants. In contrast, mice rely on embryonic cell–cell signaling to induce cells to become germ cells. Molecular evidence for inductive germ-line specification had previously been provided only for the mouse. Here we provide functional evidence for inductive germ cell specification in an invertebrate, by showing that bone morphogenetic protein (BMP) signaling, which induces mouse germ cell specification, is required for establishment of embryonic germ cells in a cricket. BMP pathway knockdown causes reduction or loss of germ cells, and elevated levels of BMP signaling cause supernumerary and ectopic germ cells. BMP-based germ cell induction in mice and crickets suggests that this may be a shared ancestral mechanism in animals.