Germ-line stem cells call the shots

In the nematode Caenorhabditis elegans, developmental biologists find that tissues derived from embryonic germ-line progenitor cells regulate reproductive costs. New work from the laboratory of Cynthia Kenyon demonstrates that signals that reduce adult survival are mediated by a small set of progenitor descendants, the germ-line stem cells, and by their interaction with components of the endocrine system. Caenorhabditis elegans is now providing a new way of understanding the mechanisms of tradeoffs between reproduction and ageing.