Studies of aging in a number of model organisms have provided insights into the mysteries of longevity. In the November 29
Flies that are heterozygous for a null or hypomorphic mutation in the gene encoding the Rpd3 deacetylase live longer than wild-type controls. The increased lifespan is equivalent to that seen in flies on a low-calorie diet. But the two effects are not additive, suggesting that they are on the same pathway. Both life-expanding treatments (diet or