A C-ELEGANS MUTANT THAT LIVES TWICE AS LONG AS WILD-TYPE

WE have found that mutations in the gene daf-2 can cause fertile, acti ve, adult Caenorhabditis elegans hermaphrodites to live more than twic e as long as wild type. This lifespan extension, the largest yet repor ted in any organism1, requires the activity of a second gene, daf-16. Both genes also regulate formation of the dauer larva, a developmental ly arrested larval form that is induced by crowding and starvation and is very long-lived2-4. Our findings raise the possibility that the lo ngevity of the dauer is not simply a consequence of its arrested growt h, but instead results from a regulated lifespan extension mechanism t hat can be uncoupled from other aspects of dauer formation. daf-2 and daf-16 provide entry points into understanding how lifespan can be ext ended.