Tor1 Sch9 affect lifespan

Researchers Find Pathways Linking Caloric Restriction To Aging Process: "UW researchers conducted a genome-wide screen of yeast cells to find which genes, and their corresponding proteins, affect lifespan. Two of the proteins, called Tor1 and Sch9, are signaling molecules that are linked to nutrient uptake in many different organisms. Their results suggest that the same proteins, or very similar ones, may be related to both nutrient response and the aging process in humans. After finding ten genes that regulate lifespan, the researchers tested two -- Tor1 and Sch9 -- to confirm their connection to caloric restriction. One test combined caloric restriction with the genetic mutation to Tor1 that reduced signaling on the TOR pathway. They saw lifespan increases in the resulting yeast cells that were about the same as a cell that had just the Tor1 mutation, indicating that the mutation was doing the same thing as caloric restriction. The TOR pathway is evolutionarily conserved, meaning it is common to many lifeforms. The other signaling protein the researchers found in the yeast study, Sch9, is the yeast version of another signaling protein called AKT, which is found in humans and other mammals. AKT is related to the regulation of the insulin and insulin-like growth factor (IGF-1) pathways, and has also been found to affect lifespan in other model organisms. "