SAMTOR is an S -adenosylmethionine sensor for the mTORC1 pathway

SAMTOR joins the family The amino acid methionine is widely appreciated to have interesting effects on animal physiology. Diets low in methionine increase longevity and overall health, particularly glucose homeostasis. Gu et al. describe a potential molecular link between the effects of methionine restriction and the growth controller mTOR complex 1 (mTORC1), a well-validated regulator of life span and health span in many organisms. They identify a protein that they named SAMTOR as a component of the nutrient-sensing pathway upstream of mTORC1. SAMTOR directly binds S-adenosylmethionine (SAM), a metabolite made from methionine, and is necessary for regulating mTORC1 in response to methionine. Science , this issue p. 813