Ruth Lehmann

While most other cells keep an organism alive, germ cells, which develop into eggs and sperm, have the unique job of creating the next generation. Our lab uses fruit flies to study how germ cells come to be so different from all the other cells in the body.

Early on in an embryo’s development, some cells have to be “set aside” to eventually become germ cells. One thing we’ve been studying is how germ granules, small molecule-making factories inside one region of the embryo, help determine which cells will take on this special fate. Recently, we figured out how these granules produce molecules that determine germ cell fate.

This year, we rebuilt a germ granule in a different part of the embryo. Using genetic techniques, we directed the usual granule components to this new location and discovered that one protein called Vasa (or DDX4) is absolutely essential for germ granule formation. This finding is especially exciting because Vasa is found in germ cells across many species, including humans. This suggests that our findings may help reveal how germ cells attain their unique potential in organisms beyond fruit flies.