Nutrient Sensing and Redox Balance: GCN2 as a New Integrator in Aging

Figure 2

GCN2-dependent nutrient sensing along aging. Amino acid deprivation activates GCN2, a kinase that induces a nutrient stress response transcriptional program through ATF4 action. GCN2 also regulates other cell processes such as autophagy, cell cycle through p53 function, and redox status by transcriptionally modulating GPX1; this homeostatic balance can be altered throughout aging. ROS: reactive oxygen species; GPX1: glutathione peroxidase 1; GCN2: general control nonderepressive 2; eIF2α: eukaryotic initiation factor 2 alpha; ATF4: activating transcription factor 4.