November 2005
Researchers uncover new genes that control longevity
In an effort to understand the molecular mechanisms that control aging, Howard Hughes Medical Institute researchers and their colleagues have now uncovered 10 new genes that regulate longevity in yeast. The studies also suggest a new model for how aging is slowed when caloric intake is restricted.
Molecular biologists Matt Kaeberlein, Brian Kennedy, Stanley Fields, and colleagues at the University of Washington, reported in the November 18, 2005, issue of the journal Science that by decreasing the function of nutrient-responsive pathways such as TOR and Sch9, the life span of yeast is extended. Fields is a Howard Hughes Medical Institute investigator at the University of Washington.
The results of the studies are important because they begin to provide an explanation for the "life extension" effect seen in laboratory animals when food is restricted. So the studies could offer new clues about the molecular mechanisms that living organisms employ when food is scarce, said Fields.
Although it seems counterintuitive, experiments showed long ago that severely restricting food intake leads to an increase in longevity � by as much as 40 percent -- in some animals. Although the longevity phenomenon was well documented in laboratory animals, researchers remained unsure about how it happened.
Now, the experiments by Kaeberlein, Kennedy, Fields and their colleagues are uncovering some of the molecular pathways that are involved in controlling longevity in yeast, and thus probably in more complex organisms.
"Through a large-scale screening process we have identified a set of genes