Primordial germ cells (PGCs) often migrate long distances through animal embryos to the future gonad, guided by attractive and repulsive cues from surrounding somatic cells. On ,Hanyu-Nakamura and co-workers investigate how the lipid phosphate phosphatases Wunen (Wun) and Wun2 control PGC (pole cell) survival and migration in Drosophila. Somatically expressed Wun and Wun2 are known to provide a repulsive cue for pole cell migration and to reduce their viability when overexpressed. But this new research shows that maternal Wun2 promotes pole cell survival in a cell-autonomous manner, and that this survival is dependent on the balance between the activity of Wun and Wun2 in somatic cells and Wun2 in pole cells. The researchers suggest that somatic Wun and Wun2 direct pole cell migration by depleting an extracellular substrate that is essential for pole cell survival, and speculate that similar mechanisms may act in other developmental processes.
