Import machinery is required for UPR ^mt -dependent lifespan extension. (a and b) Adult lifespans of glp-1(e2141ts) animals grown on bacteria expressing dsRNA from the time of hatching. Turquoise lines, the lifespan of animals grown on control bacteria containing the RNAi vector alone; purple lines, the lifespan of animals grown on bacteria expressing the dsRNA of cco-1. (a) Magenta lines, the lifespan of animals grown on bacteria expressing the dsRNA of tomm-20; green lines: the lifespan of animals grown on bacteria expressing the dsRNA of cco-1 and the dsRNA of tomm-20. (b) Lavender blue lines, the lifespan of animals grown on bacteria expressing the dsRNA of cco-1 and the dsRNA of tim-17; dark blue lines, the lifespan of animals grown on bacteria expressing the dsRNA of tim-17. a and b are presented separately for clarity. Log-rank (Mantel–Cox) method was used to determine the significant differences (*, P < 0.05; ****, P < 0.0001). (c) A schematic figure depicting the model of UPR^mt-induced upregulation of mitochondrial import.