You might recall that researchers have achieved some success in extending fly longevity via p53 - a cancer suppression gene in humans, but also related to the biochemistry of calorie restriction. Via ScienceDaily, more on that line of research: "Bauer spent a year conducting painstaking experiments. He'd take a batch of young flies, each genetically altered to reduce p53 activity in a small portion of their nervous systems, and watch the flies age. Time and again, the flies lived for about two months - the average lifespan for these insects. But when Bauer manipulated a cluster of 14 insulin-producing cells in their brains, the flies lived about 15 to 20 percent longer. ... Bauer and Helfand then wanted to know if this was caloric restriction at work. So [they] restricted the diets of the flies and ran the same experiments. The calorie-restricted flies didn't live any longer when p53 was reduced in the insulin-producing cells. This evidence supports the notion that p53 reduction is one of the direct effects of caloric restriction."