(A) and (B) cco-1 RNAi extends lifespan in wild-type (A) and fzo-1 mutants (B). (C) and (D) daf-2 RNAi extends lifespan in wild-type (C) and fzo-1 mutants (D). (E) Mitochondrial networks in wild-type and eat-2 mutant worms on day 1, 5, 8 and 15. (F) Quantification of (E): Mitochondrial content (left) and area:perimeter ratio (right). Mean ± SEM of n=8–13 muscle cells from different worms. *p<0.05, **p<0.01,***p<0.001 by t test. (G) Mitochondrial networks in day 4 worms fed ad libitum (AL, top panels) or diet-restricted (DR, bottom panels). DR for the first 4 days of adulthood induces mitochondrial network remodeling in wild-type worms, while networks remain fragmented in fzo-1 mutants. (H) and (I) Survival curves demonstrating that DR extends lifespan compared to AL controls in wild-type (H), but not in fzo-1 mutants (I). See Table S1 for lifespan statistics.