Figure 2. FIGURE 2: The functional state of mitochondria and mitochondrial ROS production in chronologically "young" yeast cells define their longevity by orchestrating numerous "downstream" cellular processes.

A model for how coupled mitochondrial respiration, mitochondrial membrane potential maintenance and mitochondrial ROS production early in life of chronologically aging yeast cells, prior to entry into a non-proliferative state, define their viability after such entry - i.e., define their longevity. Activation arrows and inhibition bars denote pro-aging processes (displayed in blue color) or anti-aging processes (displayed in red color). Please see text for additional details. CR, caloric restriction; D, diauxic growth phase; DAG, diacylglycerol; EtOH, ethanol; FFA, non-esterified ("free") fatty acids; IMM, inner mitochondrial membrane; L, logarithmic growth phase; LCA, lithocholic acid; LD, lipid droplet; PD, post-diauxic growth phase; PS, phosphatidylserine; ROS, reactive oxygen species; ST, stationary growth phase; ΔΨ_m, electrochemical potential across the IMM.